Use tile based query when creating a way from unwayed segments.
[rails.git] / app / controllers / amf_controller.rb
index a864d3dcf2a6d7a6a9a0e1d06ae2d05c63edbb86..8132b5311b5d412d631517b20457d5388f94a699 100644 (file)
 class AmfController < ApplicationController
   require 'stringio'
 
-# to log:
-# RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
+  session :off
+  before_filter :check_write_availability
+
+  # to log:
+  # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
 
   # ====================================================================
   # Main AMF handler
-  
+
   # ---- talk  process AMF request
 
   def talk
-       req=StringIO.new(request.raw_post)      # Get POST data as request
-       req.read(2)                                                     # Skip version indicator and client ID
-       results={}                                                      # Results of each body
-
-       # -------------
-       # Parse request
-
-       headers=getint(req)                                     # Read number of headers
-       for i in (1..headers)                           # Read each header
-               name=getstring(req)                             #  |
-               req.getc                                                #  | skip boolean
-               value=getvalue(req)                             #  |
-               header["name"]=value                    #  |
-       end
-
-       bodies=getint(req)                                      # Read number of bodies
-       for i in (1..bodies)                            # Read each body
-               message=getstring(req)                  #  | get message name
-               index=getstring(req)                    #  | get index in response sequence
-               bytes=getlong(req)                              #  | get total size in bytes
-               args=getvalue(req)                              #  | get response (probably an array)
-       
-               case message
-                       when 'getpresets';      results[index]=putdata(index,getpresets)
-                       when 'whichways';       results[index]=putdata(index,whichways(args))
-                       when 'getway';          results[index]=putdata(index,getway(args))
-                       when 'putway';          results[index]=putdata(index,putway(args))
-                       when 'deleteway';       results[index]=putdata(index,deleteway(args))
+    req=StringIO.new(request.raw_post) # Get POST data as request
+    req.read(2)                                                        # Skip version indicator and client ID
+    results={}                                                 # Results of each body
+
+    # -------------
+    # Parse request
+
+    headers=getint(req)                                        # Read number of headers
+
+    headers.times do                               # Read each header
+      name=getstring(req)                              #  |
+      req.getc                                         #  | skip boolean
+      value=getvalue(req)                              #  |
+      header["name"]=value                             #  |
+    end
+
+    bodies=getint(req)                                 # Read number of bodies
+    bodies.times do                                    # Read each body
+      message=getstring(req)                   #  | get message name
+      index=getstring(req)                             #  | get index in response sequence
+      bytes=getlong(req)                               #  | get total size in bytes
+      args=getvalue(req)                               #  | get response (probably an array)
+
+      case message
+                 when 'getpresets';    results[index]=putdata(index,getpresets)
+                 when 'whichways';             results[index]=putdata(index,whichways(args))
+                 when 'getway';                results[index]=putdata(index,getway(args))
+                 when 'putway';                results[index]=putdata(index,putway(args))
+                 when 'deleteway';             results[index]=putdata(index,deleteway(args))
+                 when 'makeway';               results[index]=putdata(index,makeway(args))
+                 when 'putpoi';                results[index]=putdata(index,putpoi(args))
+                 when 'getpoi';                results[index]=putdata(index,getpoi(args))
+      end
+    end
+
+    # ------------------
+    # Write out response
+
+    RAILS_DEFAULT_LOGGER.info("  Response: start")
+    a,b=results.length.divmod(256)
+       render :content_type => "application/x-amf", :text => proc { |response, output| 
+        output.write 0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
+               results.each do |k,v|
+                 output.write(v)
                end
-       end
-
-       # ------------------
-       # Write out response
-
-       response.headers["Content-Type"]="application/x-amf"
-       a,b=results.length.divmod(256)
-       ans=0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
-       results.each do |k,v|
-               ans+=v
-       end
-       render :text=>ans
+       }
+    RAILS_DEFAULT_LOGGER.info("  Response: end")
 
   end
 
+  private
 
-       # ====================================================================
-       # Remote calls
-
-       # ----- getpresets
-       #               return presets,presetmenus and presetnames arrays
-
-       def getpresets
-               presets={}
-               presetmenus={}; presetmenus['point']=[]; presetmenus['way']=[]
-               presetnames={}; presetnames['point']={}; presetnames['way']={}
-               presettype=''
-               presetcategory=''
-               
-               File.open("config/potlatch/presets.txt") do |file|
-                       file.each_line {|line|
-                               t=line.chomp
-                               if (t=~/(\w+)\/(\w+)/) then
-                                       presettype=$1
-                                       presetcategory=$2
-                                       presetmenus[presettype].push(presetcategory)
-                                       presetnames[presettype][presetcategory]=["(no preset)"]
-                               elsif (t=~/^(.+):\s?(.+)$/) then
-                                       pre=$1; kv=$2
-                                       presetnames[presettype][presetcategory].push(pre)
-                                       presets[pre]={}
-                                       kv.split(',').each {|a|
-                                               if (a=~/^(.+)=(.*)$/) then presets[pre][$1]=$2 end
-                                       }
-                               end
-                       }
-               end
-               [presets,presetmenus,presetnames]
-       end
+  # ====================================================================
+  # Remote calls
+
+  # ----- getpresets
+  #          return presets,presetmenus and presetnames arrays
+
+  def getpresets
+    presets={}
+    presetmenus={}; presetmenus['point']=[]; presetmenus['way']=[]; presetmenus['POI']=[]
+    presetnames={}; presetnames['point']={}; presetnames['way']={}; presetnames['POI']={}
+    presettype=''
+    presetcategory=''
+
+    RAILS_DEFAULT_LOGGER.info("  Message: getpresets")
+
+    #          File.open("config/potlatch/presets.txt") do |file|
+
+    # Temporary patch to get around filepath problem
+    # To remove this patch and make the code nice again:
+    # 1. uncomment above line
+    # 2. fix the path in the above line
+    # 3. delete this here document, and the following line (StringIO....)
+
+    txt=<<-EOF
+way/road
+motorway: highway=motorway,ref=(type road number)
+trunk road: highway=trunk,ref=(type road number),name=(type road name)
+primary road: highway=primary,ref=(type road number),name=(type road name)
+secondary road: highway=secondary,ref=(type road number),name=(type road name)
+residential road: highway=residential,name=(type road name)
+unclassified road: highway=unclassified,name=(type road name)
+
+way/footway
+footpath: highway=footway,foot=yes
+bridleway: highway=bridleway,foot=yes
+byway: highway=unsurfaced,foot=yes
+permissive path: highway=footway,foot=permissive
+
+way/cycleway
+cycle lane: highway=cycleway,cycleway=lane,ncn_ref=
+cycle track: highway=cycleway,cycleway=track,ncn_ref=
+cycle lane (NCN): highway=cycleway,cycleway=lane,name=(type name here),ncn_ref=(type route number)
+cycle track (NCN): highway=cycleway,cycleway=track,name=(type name here),ncn_ref=(type route number)
+
+way/waterway
+canal: waterway=canal,name=(type name here)
+navigable river: waterway=river,boat=yes,name=(type name here)
+navigable drain: waterway=drain,boat=yes,name=(type name here)
+derelict canal: waterway=derelict_canal,name=(type name here)
+unnavigable river: waterway=river,boat=no,name=(type name here)
+unnavigable drain: waterway=drain,boat=no,name=(type name here)
+
+way/railway
+railway: railway=rail
+tramway: railway=tram
+light railway: railway=light_rail
+preserved railway: railway=preserved
+disused railway tracks: railway=disused
+course of old railway: railway=abandoned
+
+way/natural
+lake: landuse=water
+forest: landuse=forest
+
+point/road
+mini roundabout: highway=mini_roundabout
+traffic lights: highway=traffic_signals
+
+point/footway
+bridge: highway=bridge
+gate: highway=gate
+stile: highway=stile
+cattle grid: highway=cattle_grid
+
+point/cycleway
+gate: highway=gate
+
+point/waterway
+lock gate: waterway=lock_gate
+weir: waterway=weir
+aqueduct: waterway=aqueduct
+winding hole: waterway=turning_point
+mooring: waterway=mooring
+
+point/railway
+station: railway=station
+viaduct: railway=viaduct
+level crossing: railway=crossing
+
+point/natural
+peak: point=peak
+
+POI/road
+car park: amenity=parking
+petrol station: amenity=fuel
+
+POI/cycleway
+bike park: amenity=bicycle_parking
+
+POI/place
+city: place=city,name=(type name here),is_in=(type region or county)
+town: place=town,name=(type name here),is_in=(type region or county)
+suburb: place=suburb,name=(type name here),is_in=(type region or county)
+village: place=village,name=(type name here),is_in=(type region or county)
+hamlet: place=hamlet,name=(type name here),is_in=(type region or county)
+
+POI/tourism
+attraction: tourism=attraction,amenity=,religion=,denomination=
+church: tourism=,amenity=place_of_worship,name=(type name here),religion=christian,denomination=(type denomination here)
+hotel: tourism=hotel,amenity=,religion=,denomination=
+other religious: tourism=,amenity=place_of_worship,name=(type name here),religion=(type religion),denomination=
+post box: amenity=post_box,tourism=,name=,religion=,denomination=
+post office: amenity=post_office,tourism=,name=,religion=,denomination=
+pub: tourism=,amenity=pub,name=(type name here),religion=,denomination=
+
+POI/natural
+peak: point=peak
+EOF
+
+    StringIO.open(txt) do |file|
+      file.each_line {|line|
+        t=line.chomp
+        if (t=~/(\w+)\/(\w+)/) then
+          presettype=$1
+          presetcategory=$2
+          presetmenus[presettype].push(presetcategory)
+          presetnames[presettype][presetcategory]=["(no preset)"]
+        elsif (t=~/^(.+):\s?(.+)$/) then
+          pre=$1; kv=$2
+          presetnames[presettype][presetcategory].push(pre)
+          presets[pre]={}
+          kv.split(',').each {|a|
+            if (a=~/^(.+)=(.*)$/) then presets[pre][$1]=$2 end
+          }
+        end
+      }
+    end
+    return [presets,presetmenus,presetnames]
+  end
 
-       # ----- whichways(left,bottom,right,top)
-       #               return array of ways in current bounding box
-       #               at present, instead of using correct (=more complex) SQL to find
-       #               corner-crossing ways, it simply enlarges the bounding box by +/- 0.01
-       
-       def whichways(args)
-               waylist=WaySegment.find_by_sql("SELECT DISTINCT current_way_segments.id AS wayid"+
-                        "  FROM current_way_segments,current_segments,current_nodes "+
-                        " WHERE segment_id=current_segments.id "+
-                        "   AND current_segments.visible=1 "+
-                        "   AND node_a=current_nodes.id "+
-                        "   AND (latitude  BETWEEN "+(args[1].to_f-0.01).to_s+" AND "+(args[3].to_f+0.01).to_s+") "+
-                        "   AND (longitude BETWEEN "+(args[0].to_f-0.01).to_s+" AND "+(args[2].to_f+0.01).to_s+")")
-               ways=[]
-               waylist.each {|a|
-                       ways<<a.wayid.to_i
-               }
-               ways
-       end
+  # ----- whichways(left,bottom,right,top)
+  #              return array of ways in current bounding box
+  #              at present, instead of using correct (=more complex) SQL to find
+  #              corner-crossing ways, it simply enlarges the bounding box by +/- 0.01
+
+  def whichways(args)
+    xmin = args[0].to_f-0.01
+    ymin = args[1].to_f-0.01
+    xmax = args[2].to_f+0.01
+    ymax = args[3].to_f+0.01
+    baselong    = args[4]
+    basey       = args[5]
+    masterscale = args[6]
+
+    RAILS_DEFAULT_LOGGER.info("  Message: whichways, bbox=#{xmin},#{ymin},#{xmax},#{ymax}")
+
+    waylist = WaySegment.find_by_sql("SELECT DISTINCT current_way_segments.id AS wayid"+
+       "  FROM current_way_segments,current_segments,current_nodes,current_ways "+
+       " WHERE segment_id=current_segments.id "+
+       "   AND current_segments.visible=1 "+
+       "   AND node_a=current_nodes.id "+
+       "   AND current_ways.id=current_way_segments.id "+
+       "   AND current_ways.visible=1 "+
+       "   AND "+OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes."))
+
+    ways = waylist.collect {|a| a.wayid.to_i } # get an array of way id's
+
+    pointlist = ActiveRecord::Base.connection.select_all("SELECT current_nodes.id,current_nodes.latitude*0.0000001 AS lat,current_nodes.longitude*0.0000001 AS lng,current_nodes.tags "+
+       "  FROM current_nodes "+
+       "  LEFT OUTER JOIN current_segments cs1 ON cs1.node_a=current_nodes.id "+
+       "  LEFT OUTER JOIN current_segments cs2 ON cs2.node_b=current_nodes.id "+
+       " WHERE "+OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")+
+       "   AND cs1.id IS NULL AND cs2.id IS NULL "+
+       "   AND current_nodes.visible=1")
+
+    points = pointlist.collect {|a| [a['id'],long2coord(a['lng'].to_f,baselong,masterscale),lat2coord(a['lat'].to_f,basey,masterscale),tag2array(a['tags'])]   } # get a list of node ids and their tags
+
+    return [ways,points]
+  end
 
-       # ----- getway (objectname, way, baselong, basey, masterscale)
-       #               returns objectname, array of co-ordinates, attributes,
-       #                               xmin,xmax,ymin,ymax
-       
-       def getway(args)
-               objname,wayid,baselong,basey,masterscale=args
-               wayid=wayid.to_i
-               points=[]
-               lastid=-1
-               xmin=999999; xmax=-999999
-               ymin=999999; ymax=-999999
-
-               readwayquery(wayid).each {|row|
-                       xs1=long2coord(row['long1'].to_f,baselong,masterscale); ys1=lat2coord(row['lat1'].to_f,basey,masterscale)
-                       xs2=long2coord(row['long2'].to_f,baselong,masterscale); ys2=lat2coord(row['lat2'].to_f,basey,masterscale)
-                       if (row['id1'].to_i!=lastid)
-                               points<<[xs1,ys1,row['id1'].to_i,0,tag2array(row['tags1']),0]
-                       end
-                       lastid=row['id2'].to_i
-                       points<<[xs2,ys2,row['id2'].to_i,1,tag2array(row['tags2']),row['segment_id'].to_i]
-                       xmin=[xmin,row['long1'].to_f,row['long2'].to_f].min
-                       xmax=[xmax,row['long1'].to_f,row['long2'].to_f].max
-                       ymin=[ymin,row['lat1'].to_f,row['lat2'].to_f].min
-                       ymax=[ymax,row['lat1'].to_f,row['lat2'].to_f].max
-               }
-
-               attributes={}
-               attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM current_way_tags WHERE id=#{wayid}"
-               attrlist.each {|a| attributes[a['k']]=a['v'] }
-
-               [objname,points,attributes,xmin,xmax,ymin,ymax]
-       end
-       
-       # ----- putway (user token, way, array of co-ordinates, array of attributes,
-       #                               baselong, basey, masterscale)
-       #               returns current way ID, new way ID, hash of renumbered nodes,
-       #                               xmin,xmax,ymin,ymax
-
-       def putway(args)
-               usertoken,originalway,points,attributes,baselong,basey,masterscale=args
-               uid=getuserid(usertoken); if !uid then return end
-               db_uqs='uniq'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s     # temp uniquesegments table name, typically 51 chars
-               db_now='@now'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s     # 'now' variable name, typically 51 chars
-               ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
-               originalway=originalway.to_i
-               
-               # -- 3. read original way into memory
-       
-               xc={}; yc={}; tagc={}; seg={}
-               if (originalway>0)
-                       way=originalway
-                       readwayquery(way).each { |row|
-                               id1=row['id1'].to_i; xc[id1]=row['long1'].to_f; yc[id1]=row['lat1'].to_f; tagc[id1]=row['tags1']
-                               id2=row['id2'].to_i; xc[id2]=row['long2'].to_f; yc[id2]=row['lat2'].to_f; tagc[id2]=row['tags2']
-                               seg[row['segment_id'].to_i]=id1.to_s+'-'+id2.to_s
-                       }
-               else
-                       way=ActiveRecord::Base.connection.insert("INSERT INTO current_ways (user_id,timestamp,visible) VALUES (#{uid},#{db_now},1)")
-               end
+  # ----- getway (objectname, way, baselong, basey, masterscale)
+  #              returns objectname, array of co-ordinates, attributes,
+  #                              xmin,xmax,ymin,ymax
+
+  def getway(args)
+    objname,wayid,baselong,basey,masterscale=args
+    wayid = wayid.to_i
+    points = []
+    lastid = -1
+    xmin = ymin = 999999
+    xmax = ymax = -999999
+
+    RAILS_DEFAULT_LOGGER.info("  Message: getway, id=#{wayid}")
+
+    readwayquery(wayid).each {|row|
+      xs1=long2coord(row['long1'].to_f,baselong,masterscale); ys1=lat2coord(row['lat1'].to_f,basey,masterscale)
+      xs2=long2coord(row['long2'].to_f,baselong,masterscale); ys2=lat2coord(row['lat2'].to_f,basey,masterscale)
+      points << [xs1,ys1,row['id1'].to_i,0,tag2array(row['tags1']),0] if (row['id1'].to_i!=lastid)
+      lastid = row['id2'].to_i
+      points << [xs2,ys2,row['id2'].to_i,1,tag2array(row['tags2']),row['segment_id'].to_i]
+      xmin = [xmin,row['long1'].to_f,row['long2'].to_f].min
+      xmax = [xmax,row['long1'].to_f,row['long2'].to_f].max
+      ymin = [ymin,row['lat1'].to_f,row['lat2'].to_f].min
+      ymax = [ymax,row['lat1'].to_f,row['lat2'].to_f].max
+    }
+
+    attributes={}
+    attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM current_way_tags WHERE id=#{wayid}"
+    attrlist.each {|a| attributes[a['k']]=a['v'] }
+
+    [objname,points,attributes,xmin,xmax,ymin,ymax]
+  end
 
-               # -- 4. get version by inserting new row into ways
+  # -----      putway (user token, way, array of co-ordinates, array of attributes,
+  #                                    baselong, basey, masterscale)
+  #                    returns current way ID, new way ID, hash of renumbered nodes,
+  #                                    xmin,xmax,ymin,ymax
+
+  def putway(args)
+    usertoken,originalway,points,attributes,baselong,basey,masterscale=args
+    uid=getuserid(usertoken)
+    return if !uid
+    db_uqs='uniq'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s        # temp uniquesegments table name, typically 51 chars
+    db_uqn='unin'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s        # temp uniquenodes table name, typically 51 chars
+    db_now='@now'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s        # 'now' variable name, typically 51 chars
+    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
+    originalway=originalway.to_i
+
+    RAILS_DEFAULT_LOGGER.info("  Message: putway, id=#{originalway}")
+
+    # -- 3.    read original way into memory
+
+    xc={}; yc={}; tagc={}; seg={}
+    if originalway>0
+      way=originalway
+      readwayquery(way).each { |row|
+        id1=row['id1'].to_i; xc[id1]=row['long1'].to_f; yc[id1]=row['lat1'].to_f; tagc[id1]=row['tags1']
+        id2=row['id2'].to_i; xc[id2]=row['long2'].to_f; yc[id2]=row['lat2'].to_f; tagc[id2]=row['tags2']
+        seg[row['segment_id'].to_i]=id1.to_s+'-'+id2.to_s
+      }
+      ActiveRecord::Base.connection.update("UPDATE current_ways SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id=#{way}")
+    else
+      way=ActiveRecord::Base.connection.insert("INSERT INTO current_ways (user_id,timestamp,visible) VALUES (#{uid},#{db_now},1)")
+    end
+
+    # -- 4.    get version by inserting new row into ways
+
+    version=ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},1)")
+
+    # -- 5. compare nodes and update xmin,xmax,ymin,ymax
+
+    xmin = ymin = 999999
+    xmax = ymax = -999999
+    insertsql = ''
+    renumberednodes={}
+
+    points.each_index do |i|
+      xs=coord2long(points[i][0],masterscale,baselong)
+      ys=coord2lat(points[i][1],masterscale,basey)
+      xmin=[xs,xmin].min; xmax=[xs,xmax].max
+      ymin=[ys,ymin].min; ymax=[ys,ymax].max
+      node=points[i][2].to_i
+      tagstr=array2tag(points[i][4])
+      tagstr=tagstr.gsub(/[\000-\037]/,"")
+      tagsql="'"+sqlescape(tagstr)+"'"
+      lat=(ys * 10000000).round
+      long=(xs * 10000000).round
+      tile=QuadTile.tile_for_point(ys, xs)
+
+      # compare node
+      if node<0
+        # new node - create
+       if renumberednodes[node.to_s].nil?
+          newnode=ActiveRecord::Base.connection.insert("INSERT INTO current_nodes (   latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (           #{lat},#{long},#{db_now},#{uid},1,#{tagsql},#{tile})")
+                  ActiveRecord::Base.connection.insert("INSERT INTO nodes         (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{newnode},#{lat},#{long},#{db_now},#{uid},1,#{tagsql},#{tile})")
+          points[i][2]=newnode
+          renumberednodes[node.to_s]=newnode.to_s
+       else
+          points[i][2]=renumberednodes[node.to_s].to_i
+       end
+
+      elsif xc.has_key?(node)
+        # old node from original way - update
+        if (xs!=xc[node] or ys!=yc[node] or tagstr!=tagc[node])
+          ActiveRecord::Base.connection.insert("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{node},#{lat},#{long},#{db_now},#{uid},1,#{tagsql},#{tile})")
+          ActiveRecord::Base.connection.update("UPDATE current_nodes SET latitude=#{lat},longitude=#{long},timestamp=#{db_now},user_id=#{uid},tags=#{tagsql},visible=1,tile=#{tile} WHERE id=#{node}")
+        end
+      else
+        # old node, created in another way and now added to this way
+      end
+    end
+
+
+    # -- 6.i compare segments
+
+    numberedsegments={}
+    seglist=''                         # list of existing segments that we want to keep
+    for i in (0..(points.length-2))
+      if (points[i+1][3].to_i==0) then next end
+      segid=points[i+1][5].to_i
+      from =points[i  ][2].to_i
+      to   =points[i+1][2].to_i
+      if seg.has_key?(segid)
+       # if segment exists, check it still refers to the same nodes
+        if seg[segid]=="#{from}-#{to}" then 
+          if (seglist!='') then seglist+=',' end; seglist+=segid.to_s
+          next
+        end
+      elsif segid>0
+        # not in previous version of way, but supplied, so assume
+        # that it's come from makeway (i.e. unwayed segments)
+        if (seglist!='') then seglist+=',' end; seglist+=segid.to_s
+        next
+      end
+      segid=ActiveRecord::Base.connection.insert("INSERT INTO current_segments (   node_a,node_b,timestamp,user_id,visible,tags) VALUES (         #{from},#{to},#{db_now},#{uid},1,'')")
+            ActiveRecord::Base.connection.insert("INSERT INTO segments         (id,node_a,node_b,timestamp,user_id,visible,tags) VALUES (#{segid},#{from},#{to},#{db_now},#{uid},1,'')")
+      points[i+1][5]=segid
+      numberedsegments[(i+1).to_s]=segid.to_s
+    end
+
+
+    # -- 6.ii insert new way segments
+
+    createuniquesegments(way,db_uqs,seglist)   # segments which appear in this way but no other
+
+    #          delete segments from uniquesegments (and not in modified way)
+
+    sql=<<-EOF
+      INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible) 
+      SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0
+        FROM current_segments AS cs, #{db_uqs} AS us
+       WHERE cs.id=us.segment_id AND cs.visible=1 
+    EOF
+    ActiveRecord::Base.connection.insert(sql)
+
+    sql=<<-EOF
+         UPDATE current_segments AS cs, #{db_uqs} AS us
+          SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid} 
+        WHERE cs.id=us.segment_id AND cs.visible=1 
+    EOF
+    ActiveRecord::Base.connection.update(sql)
+
+    #          delete nodes not in modified way or any other segments
+
+    createuniquenodes(db_uqs,db_uqn)   # nodes which appear in this way but no other
+
+    sql=<<-EOF
+       INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tile)  
+       SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0,cn.tile
+         FROM current_nodes AS cn,#{db_uqn}
+        WHERE cn.id=node_id
+    EOF
+    ActiveRecord::Base.connection.insert(sql)
+
+    sql=<<-EOF
+      UPDATE current_nodes AS cn, #{db_uqn}
+         SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
+       WHERE cn.id=node_id
+    EOF
+    ActiveRecord::Base.connection.update(sql)
+
+    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
+    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
+
+    #          insert new version of route into way_segments
+
+    insertsql =''
+    currentsql=''
+    sequence  =1
+    for i in (0..(points.length-2))
+      if (points[i+1][3].to_i==0) then next end
+      if insertsql !='' then insertsql +=',' end
+      if currentsql!='' then currentsql+=',' end
+      insertsql +="(#{way},#{points[i+1][5]},#{version})"
+      currentsql+="(#{way},#{points[i+1][5]},#{sequence})"
+      sequence  +=1
+    end
+
+    ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}");
+    ActiveRecord::Base.connection.insert("INSERT INTO         way_segments (id,segment_id,version    ) VALUES #{insertsql}");
+    ActiveRecord::Base.connection.insert("INSERT INTO current_way_segments (id,segment_id,sequence_id) VALUES #{currentsql}");
+
+    # -- 7. insert new way tags
+
+    insertsql =''
+    currentsql=''
+    attributes.each do |k,v|
+      if v=='' or v.nil? then next end
+      if v[0,6]=='(type ' then next end
+      if insertsql !='' then insertsql +=',' end
+      if currentsql!='' then currentsql+=',' end
+         k=k.gsub(/[\000-\037]/,"")
+         v=v.gsub(/[\000-\037]/,"")
+      insertsql +="(#{way},'"+sqlescape(k)+"','"+sqlescape(v)+"',#{version})"
+      currentsql+="(#{way},'"+sqlescape(k)+"','"+sqlescape(v)+"')"
+    end
+
+    ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
+    if (insertsql !='') then ActiveRecord::Base.connection.insert("INSERT INTO way_tags (id,k,v,version) VALUES #{insertsql}" ) end
+    if (currentsql!='') then ActiveRecord::Base.connection.insert("INSERT INTO current_way_tags (id,k,v) VALUES #{currentsql}") end
+
+    [originalway,way,renumberednodes,numberedsegments,xmin,xmax,ymin,ymax]
+  end
 
-               version=ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},1)")
+  # -----      putpoi (user token, id, x,y,tag array,visible,baselong,basey,masterscale)
+  #                    returns current id, new id
+  #                    if new: add new row to current_nodes and nodes
+  #                    if old: add new row to nodes, update current_nodes
+
+  def putpoi(args)
+    usertoken,id,x,y,tags,visible,baselong,basey,masterscale=args
+    uid=getuserid(usertoken)
+    return if !uid
+    db_now='@now'+uid.to_s+id.to_i.abs.to_s+Time.new.to_i.to_s # 'now' variable name, typically 51 chars
+    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
+
+    id=id.to_i
+    visible=visible.to_i
+    x=coord2long(x.to_f,masterscale,baselong)
+    y=coord2lat(y.to_f,masterscale,basey)
+    tagsql="'"+sqlescape(array2tag(tags))+"'"
+    lat=(y * 10000000).round
+    long=(x * 10000000).round
+    tile=QuadTile.tile_for_point(y, x)
+       
+    if (id>0) then
+        ActiveRecord::Base.connection.insert("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{id},#{lat},#{long},#{db_now},#{uid},#{visible},#{tagsql},#{tile})");
+        ActiveRecord::Base.connection.update("UPDATE current_nodes SET latitude=#{lat},longitude=#{long},timestamp=#{db_now},user_id=#{uid},visible=#{visible},tags=#{tagsql},tile=#{tile} WHERE id=#{id}");
+        newid=id
+    else
+        newid=ActiveRecord::Base.connection.insert("INSERT INTO current_nodes (latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{lat},#{long},#{db_now},#{uid},#{visible},#{tagsql},#{tile})");
+              ActiveRecord::Base.connection.update("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{newid},#{lat},#{long},#{db_now},#{uid},#{visible},#{tagsql},#{tile})");
+    end
+    [id,newid]
+  end
 
-               # -- 5. compare nodes and update xmin,xmax,ymin,ymax
+  # -----      getpoi (id,baselong,basey,masterscale)
+  #                    returns id,x,y,tag array
+  
+  def getpoi(args)
+       id,baselong,basey,masterscale=args; id=id.to_i
+       poi=ActiveRecord::Base.connection.select_one("SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lng,tags "+
+               "FROM current_nodes WHERE visible=1 AND id=#{id}")
+       if poi.nil? then return [nil,nil,nil,''] end
+       [id,
+        long2coord(poi['lng'].to_f,baselong,masterscale),
+        lat2coord(poi['lat'].to_f,basey,masterscale),
+        tag2array(poi['tags'])]
+  end
 
-               xmin=999999; xmax=-999999
-               ymin=999999; ymax=-999999
-               insertsql=''
-               nodelist=''
-               renumberednodes={}
-       
-               points.each_index do |i|
-                       xs=coord2long(points[i][0],masterscale,baselong)
-                       ys=coord2lat(points[i][1],masterscale,basey)
-                       xmin=[xs,xmin].min; xmax=[xs,xmax].max
-                       ymin=[ys,ymin].min; ymax=[ys,ymax].max
-                       node=points[i][2].to_i
-                       tagstr=array2tag(points[i][4])
-                       tagsql="'"+sqlescape(tagstr)+"'"
-       
-                       # compare node
-                       if node<0
-                               # new node - create
-                               newnode=ActiveRecord::Base.connection.insert("INSERT INTO current_nodes (   latitude,longitude,timestamp,user_id,visible,tags) VALUES (           #{ys},#{xs},#{db_now},#{uid},1,#{tagsql})")
-                                               ActiveRecord::Base.connection.insert("INSERT INTO nodes         (id,latitude,longitude,timestamp,user_id,visible,tags) VALUES (#{newnode},#{ys},#{xs},#{db_now},#{uid},1,#{tagsql})")
-                               points[i][2]=newnode
-                               renumberednodes[node.to_s]=newnode.to_s
-                               
-                       elsif xc.has_key?(node)
-                               # old node from original way - update
-                               if (xs!=xc[node] or (ys/0.0000001).round!=(yc[node]/0.0000001).round or tagstr!=tagc[node])
-                                       ActiveRecord::Base.connection.insert("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags) VALUES (#{node},#{ys},#{xs},#{db_now},#{uid},1,#{tagsql})")
-                                       ActiveRecord::Base.connection.update("UPDATE current_nodes SET latitude=#{ys},longitude=#{xs},timestamp=#{db_now},user_id=#{uid},tags=#{tagsql},visible=1 WHERE id=#{node}")
-                               else
-                                       if (nodelist!='') then nodelist+=',' end; nodelist+=node.to_s
-                               end
-                       else
-                               # old node, created in another way and now added to this way
-                               if (nodelist!='') then nodelist+=',' end; nodelist+=node.to_s
-                       end
-       
-               end
+  # -----      deleteway (user token, way)
+  #                    returns way ID only
 
-               if nodelist!='' then
-                       ActiveRecord::Base.connection.update("UPDATE current_nodes SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id IN (#{nodelist})")
-               end
+  def deleteway(args)
+    usertoken,way=args
 
-               # -- 6.i compare segments
-       
-               numberedsegments={}
-               seglist=''
-               for i in (0..(points.length-2))
-                       if (points[i+1][3].to_i==0) then next end
-                       segid=points[i+1][5].to_i
-                       from =points[i  ][2].to_i
-                       to   =points[i+1][2].to_i
-                       if seg.has_key?(segid)
-                               if seg[segid]=="#{from}-#{to}" then 
-                                       if (seglist!='') then seglist+=',' end; seglist+=segid.to_s
-                                       next
-                               end
-                       end
-                       segid=ActiveRecord::Base.connection.insert("INSERT INTO current_segments (   node_a,node_b,timestamp,user_id,visible,tags) VALUES (         #{from},#{to},#{db_now},#{uid},1,'')")
-                                 ActiveRecord::Base.connection.insert("INSERT INTO segments         (id,node_a,node_b,timestamp,user_id,visible,tags) VALUES (#{segid},#{from},#{to},#{db_now},#{uid},1,'')")
-                       points[i+1][5]=segid
-                       numberedsegments[(i+1).to_s]=segid.to_s
-               end
-               # numberedsegments.each{|a,b| RAILS_DEFAULT_LOGGER.error("Sending back: seg no. #{a} -> id #{b}") }
+    RAILS_DEFAULT_LOGGER.info("  Message: deleteway, id=#{way}")
 
-               if seglist!='' then
-                       ActiveRecord::Base.connection.update("UPDATE current_segments SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id IN (#{seglist})")
-               end
+    uid=getuserid(usertoken); if !uid then return end
+    way=way.to_i
 
+    db_uqs='uniq'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s        # temp uniquesegments table name, typically 51 chars
+    db_uqn='unin'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s        # temp uniquenodes table name, typically 51 chars
+    db_now='@now'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s        # 'now' variable name, typically 51 chars
+    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
+    createuniquesegments(way,db_uqs,'')
 
-               # -- 6.ii insert new way segments
+    # -        delete any otherwise unused segments
 
-               createuniquesegments(way,db_uqs)
+    sql=<<-EOF
+      INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible) 
+      SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0 
+        FROM current_segments AS cs, #{db_uqs} AS us
+       WHERE cs.id=us.segment_id
+    EOF
+    ActiveRecord::Base.connection.insert(sql)
 
-               # a=''
-               # ActiveRecord::Base.connection.select_values("SELECT segment_id FROM #{db_uqs}").each {|b| a+=b+',' }
-               # RAILS_DEFAULT_LOGGER.error("Unique segments are #{a}")
-               # a=ActiveRecord::Base.connection.select_value("SELECT #{db_now}")
-               # RAILS_DEFAULT_LOGGER.error("Timestamp of this edit is #{a}")
-               # RAILS_DEFAULT_LOGGER.error("Userid of this edit is #{uid}")
+    sql=<<-EOF
+      UPDATE current_segments AS cs, #{db_uqs} AS us
+         SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid} 
+       WHERE cs.id=us.segment_id
+    EOF
+    ActiveRecord::Base.connection.update(sql)
 
-               #               delete nodes from uniquesegments (and not in modified way)
-       
-               sql=<<-EOF
-                       INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible)  
-                       SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0 
-                         FROM current_nodes AS cn, 
-                                  current_segments AS cs,
-                                  #{db_uqs} AS us 
-                        WHERE(cn.id=cs.node_a OR cn.id=cs.node_b) 
-                          AND cs.id=us.segment_id AND cs.visible=1 
-                          AND (cn.timestamp!=#{db_now} OR cn.user_id!=#{uid})
-               EOF
-               ActiveRecord::Base.connection.insert(sql)
+    # - delete any unused nodes
+  
+    createuniquenodes(db_uqs,db_uqn)
+
+    sql=<<-EOF
+       INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tile)
+       SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0,cn.tile
+         FROM current_nodes AS cn,#{db_uqn}
+        WHERE cn.id=node_id
+    EOF
+    ActiveRecord::Base.connection.insert(sql)
+
+    sql=<<-EOF
+      UPDATE current_nodes AS cn, #{db_uqn}
+         SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
+       WHERE cn.id=node_id
+    EOF
+    ActiveRecord::Base.connection.update(sql)
+       
+    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
+    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
+
+    # - delete way
+       
+    ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},0)")
+    ActiveRecord::Base.connection.update("UPDATE current_ways SET user_id=#{uid},timestamp=#{db_now},visible=0 WHERE id=#{way}")
+    ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}")
+    ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
+       
+    way
+end
 
+# ----- makeway(x,y,baselong,basey,masterscale)
+#              returns way made from unwayed segments
+
+def makeway(args)
+       usertoken,x,y,baselong,basey,masterscale=args
+    uid=getuserid(usertoken)
+    return if !uid
+
+       points=[]
+       toreverse=[]                            # segments to reverse
+       nodesused={}                            # so we don't go over the same node twice
+
+       # - find start point near x
+       
+       xc=coord2long(x,masterscale,baselong)
+       yc=coord2lat(y,masterscale,basey)
+
+        RAILS_DEFAULT_LOGGER.info("  Message: makeway, xc=#{xc}, y=#{yc}")
+
+       xs1=xc-0.001; xs2=xc+0.001
+       ys1=yc-0.001; ys2=yc+0.001
+       
+       sql=<<-EOF
+               SELECT cn1.latitude*0.0000001 AS lat1,cn1.longitude*0.0000001 AS lon1,cn1.id AS id1,
+                      cn2.latitude*0.0000001 AS lat2,cn2.longitude*0.0000001 AS lon2,cn2.id AS id2, cs.id AS segid
+                 FROM current_nodes AS cn1,
+                      current_nodes AS cn2,
+                      current_segments AS cs 
+                      LEFT OUTER JOIN current_way_segments ON segment_id=cs.id 
+                WHERE #{OSM.sql_for_area(ys1,xs1,ys2,xs2,"cn1.")}
+                  AND segment_id IS NULL 
+                   AND cs.visible=1
+                  AND cn1.id=node_a AND cn1.visible=1 
+                  AND cn2.id=node_b AND cn2.visible=1 
+             ORDER BY SQRT(POW(cn1.longitude-#{xc},2)+
+                               POW(cn1.latitude -#{yc},2)) 
+        LIMIT 1
+       EOF
+       row=ActiveRecord::Base.connection.select_one sql
+       if row.nil? then return [0,0,0,0,0] end
+       xs1=long2coord(row['lon1'].to_f,baselong,masterscale); ys1=lat2coord(row['lat1'].to_f,basey,masterscale)
+       xs2=long2coord(row['lon2'].to_f,baselong,masterscale); ys2=lat2coord(row['lat2'].to_f,basey,masterscale)
+       xmin=[xs1,xs2].min; xmax=[xs1,xs2].max
+       ymin=[ys1,ys2].min; ymax=[ys1,ys2].max
+       nodesused[row['id1'].to_i]=true
+       nodesused[row['id2'].to_i]=true
+       points<<[xs1,ys1,row['id1'].to_i,1,{},0]
+       points<<[xs2,ys2,row['id2'].to_i,1,{},row['segid'].to_i]
+       
+       # - extend at start, then end
+       while (a,point,nodesused,toreverse=findconnect(points[0][2],nodesused,'b',toreverse,baselong,basey,masterscale))[0]
+               points[0][5]=point[5]; point[5]=0       # segment leads to next node
+               points.unshift(point)
+               xmin=[point[0],xmin].min; xmax=[point[0],xmax].max
+               ymin=[point[1],ymin].min; ymax=[point[1],ymax].max
+       end
+       while (a,point,nodesused,toreverse=findconnect(points[-1][2],nodesused,'a',toreverse,baselong,basey,masterscale))[0]
+               points.push(point)
+               xmin=[point[0],xmin].min; xmax=[point[0],xmax].max
+               ymin=[point[1],ymin].min; ymax=[point[1],ymax].max
+       end
+       points[0][3]=0  # start with a move
+
+       # reverse segments in toreverse
+       if toreverse.length>0
                sql=<<-EOF
-                       UPDATE current_nodes AS cn, 
-                                  current_segments AS cs, 
-                                  #{db_uqs} AS us 
-                          SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
-                        WHERE (cn.id=cs.node_a OR cn.id=cs.node_b) 
-                          AND cs.id=us.segment_id AND cs.visible=1 
-                          AND (cn.timestamp!=#{db_now} OR cn.user_id!=#{uid})
+                       UPDATE current_segments c1, current_segments c2 
+                          SET c1.node_a=c2.node_b,c1.node_b=c2.node_a,
+                              c1.timestamp=NOW(),c1.user_id=#{uid} 
+                        WHERE c1.id=c2.id 
+                          AND c1.id IN (#{toreverse.join(',')})
                EOF
-               ActiveRecord::Base.connection.update(sql)
-       
-               #               delete segments from uniquesegments (and not in modified way)
-       
+               ActiveRecord::Base.connection.update sql
                sql=<<-EOF
-                       INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible) 
-                       SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0
-                         FROM current_segments AS cs, #{db_uqs} AS us
-                        WHERE cs.id=us.segment_id AND cs.visible=1 
-                          AND (cs.timestamp!=#{db_now} OR cs.user_id!=#{uid})
+                       INSERT INTO segments 
+                  (SELECT * FROM current_segments 
+                    WHERE id IN (#{toreverse.join(',')}))
                EOF
-               ActiveRecord::Base.connection.insert(sql)
-               
-               sql=<<-EOF
-                          UPDATE current_segments AS cs, #{db_uqs} AS us
-                                 SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid} 
-                               WHERE cs.id=us.segment_id AND cs.visible=1 
-                                 AND (cs.timestamp!=#{db_now} OR cs.user_id!=#{uid})
-               EOF
-               ActiveRecord::Base.connection.update(sql)
-               ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
+               ActiveRecord::Base.connection.insert sql
+       end
 
-               #               insert new version of route into way_segments
-       
-               insertsql =''
-               currentsql=''
-               sequence  =1
-               for i in (0..(points.length-2))
-                       if (points[i+1][3].to_i==0) then next end
-                       if insertsql !='' then insertsql +=',' end
-                       if currentsql!='' then currentsql+=',' end
-                       insertsql +="(#{way},#{points[i+1][5]},#{version})"
-                       currentsql+="(#{way},#{points[i+1][5]},#{sequence})"
-                       sequence  +=1
-               end
-               
-               ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}");
-               ActiveRecord::Base.connection.insert("INSERT INTO         way_segments (id,segment_id,version    ) VALUES #{insertsql}");
-               ActiveRecord::Base.connection.insert("INSERT INTO current_way_segments (id,segment_id,sequence_id) VALUES #{currentsql}");
-       
-               # -- 7. insert new way tags
-       
-               insertsql =''
-               currentsql=''
-               attributes.each do |k,v|
-                       if v=='' then next end
-                       if v[0,6]=='(type ' then next end
-                       if insertsql !='' then insertsql +=',' end
-                       if currentsql!='' then currentsql+=',' end
-                       insertsql +="(#{way},'"+sqlescape(k)+"','"+sqlescape(v)+"',version)"
-                       currentsql+="(#{way},'"+sqlescape(k)+"','"+sqlescape(v)+"')"
+       [points,xmin,xmax,ymin,ymax]
+end
+
+def findconnect(id,nodesused,lookfor,toreverse,baselong,basey,masterscale)
+       # get all segments with 'id' as a point
+       # (to look for both node_a and node_b, UNION is faster than node_a=id OR node_b=id)!
+       sql=<<-EOF
+               SELECT cn1.latitude*0.0000001 AS lat1,cn1.longitude*0.0000001 AS lon1,cn1.id AS id1,
+                      cn2.latitude*0.0000001 AS lat2,cn2.longitude*0.0000001 AS lon2,cn2.id AS id2, cs.id AS segid
+                 FROM current_nodes AS cn1,
+                      current_nodes AS cn2,
+                      current_segments AS cs 
+                      LEFT OUTER JOIN current_way_segments ON segment_id=cs.id 
+                WHERE segment_id IS NULL 
+                   AND cs.visible=1
+                  AND cn1.id=node_a AND cn1.visible=1 
+                  AND cn2.id=node_b AND cn2.visible=1 
+                  AND node_a=#{id}
+       UNION
+               SELECT cn1.latitude*0.0000001 AS lat1,cn1.longitude*0.0000001 AS lon1,cn1.id AS id1,
+                      cn2.latitude*0.0000001 AS lat2,cn2.longitude*0.0000001 AS lon2,cn2.id AS id2, cs.id AS segid
+                 FROM current_nodes AS cn1,
+                      current_nodes AS cn2,
+                      current_segments AS cs 
+                      LEFT OUTER JOIN current_way_segments ON segment_id=cs.id 
+                WHERE segment_id IS NULL 
+                   AND cs.visible=1
+                  AND cn1.id=node_a AND cn1.visible=1 
+                  AND cn2.id=node_b AND cn2.visible=1 
+                  AND node_b=#{id}
+       EOF
+       connectlist=ActiveRecord::Base.connection.select_all sql
+       
+       if lookfor=='b' then tocol='id1'; tolat='lat1'; tolon='lon1'; fromcol='id2'; fromlat='lat2'; fromlon='lon2'
+                                       else tocol='id2'; tolat='lat2'; tolon='lon2'; fromcol='id1'; fromlat='lat1'; fromlon='lon1'
+       end
+       
+       # eliminate those already in the hash
+       connex=0
+       point=nil
+       connectlist.each { |row|
+               tonode=row[tocol].to_i
+               fromnode=row[fromcol].to_i
+               if id==tonode and !nodesused.has_key?(fromnode)
+                       # wrong way round; add, then add to 'segments to reverse' list
+                       connex+=1
+                       nodesused[fromnode]=true
+                       point=[long2coord(row[fromlon].to_f,baselong,masterscale),lat2coord(row[fromlat].to_f,basey,masterscale),fromnode,1,{},row['segid'].to_i]
+                       toreverse.push(row['segid'].to_i)
+               elsif id==fromnode and !nodesused.has_key?(tonode)
+                       # right way round; just add
+                       connex+=1
+                       point=[long2coord(row[tolon].to_f,baselong,masterscale),lat2coord(row[tolat].to_f,basey,masterscale),tonode,1,{},row['segid'].to_i]
+                       nodesused[tonode]=true
                end
-               
-               ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
-               if (insertsql !='') then ActiveRecord::Base.connection.insert("INSERT INTO way_tags (id,k,v,version) VALUES #{insertsql}" ) end
-               if (currentsql!='') then ActiveRecord::Base.connection.insert("INSERT INTO current_way_tags (id,k,v) VALUES #{currentsql}") end
-       
-               [originalway,way,renumberednodes,numberedsegments,xmin,xmax,ymin,ymax]
-       end
-       
-       # ----- deleteway (user token, way)
-       #               returns way ID only
-       
-       def deleteway(args)
-               usertoken,way=args
-               uid=getuserid(usertoken); if !uid then return end
-               way=way.to_i
-
-               db_uqs='uniq'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s     # temp uniquesegments table name, typically 51 chars
-               db_now='@now'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s     # 'now' variable name, typically 51 chars
-               ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
-               createuniquesegments(way,db_uqs)
-       
-               sql=<<-EOF
-                       INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible) 
-                       SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0 
-                         FROM current_nodes AS cn, 
-                                  current_segments AS cs, 
-                                  #{db_uqs} AS us
-                        WHERE (cn.id=cs.node_a OR cn.id=cs.node_b) 
-                          AND cs.id=us.segment_id
-               EOF
-               ActiveRecord::Base.connection.insert(sql)
-       
-               sql=<<-EOF
-                       UPDATE current_nodes AS cn, 
-                                  current_segments AS cs, 
-                                  #{db_uqs} AS us
-                          SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
-                        WHERE (cn.id=cs.node_a OR cn.id=cs.node_b) 
-                          AND cs.id=us.segment_id
-               EOF
-               ActiveRecord::Base.connection.update(sql)
-       
-               # -     delete any otherwise unused segments
-                               
-               sql=<<-EOF
-                       INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible) 
-                       SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0 
-                         FROM current_segments AS cs, #{db_uqs} AS us
-                        WHERE cs.id=us.segment_id
-               EOF
-               ActiveRecord::Base.connection.insert(sql)
-                               
-               sql=<<-EOF
-                       UPDATE current_segments AS cs, #{db_uqs} AS us
-                          SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid} 
-                        WHERE cs.id=us.segment_id
-               EOF
-               ActiveRecord::Base.connection.update(sql)
-               ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
-       
-               # - delete way
-               
-               ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},0)")
-               ActiveRecord::Base.connection.update("UPDATE current_ways SET user_id=#{uid},timestamp=#{db_now},visible=0 WHERE id=#{way}")
-               ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}")
-               ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
-       
-               way
-       end
+       }
        
-       # ====================================================================
-       # Support functions for remote calls
-
-       def readwayquery(id)
-               ActiveRecord::Base.connection.select_all "SELECT n1.latitude AS lat1,n1.longitude AS long1,n1.id AS id1,n1.tags as tags1, "+
-                       "                 n2.latitude AS lat2,n2.longitude AS long2,n2.id AS id2,n2.tags as tags2,segment_id "+
-                       "    FROM current_way_segments,current_segments,current_nodes AS n1,current_nodes AS n2 "+
-                       "   WHERE current_way_segments.id=#{id} "+
-                       "     AND segment_id=current_segments.id "+
-                       "     AND n1.id=node_a and n2.id=node_b "+
-                       "   ORDER BY sequence_id"
+       # if only one left, then add it; otherwise return false
+       if connex!=1 or point.nil? then
+               return [false,[],nodesused,toreverse]
+       else
+               return [true,point,nodesused,toreverse]
        end
+end
 
-       def createuniquesegments(way,uqs_name)
-               sql=<<-EOF
-                       CREATE TEMPORARY TABLE #{uqs_name}
-                                                       SELECT a.segment_id,COUNT(a.segment_id) AS ct
-                                                         FROM current_way_segments AS a, current_way_segments AS b
-                                                        WHERE a.segment_id=b.segment_id 
-                                                          AND a.id=#{way} 
-                                                 GROUP BY a.segment_id
-                                                       HAVING ct=1
-               EOF
-               ActiveRecord::Base.connection.execute(sql)
-       end
-       
 
-       def sqlescape(a)
-               a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
-       end
+# ====================================================================
+# Support functions for remote calls
 
-       def tag2array(a)
-               tags={}
-               a.gsub(';;;','#%').split(';').each do |b|
-                       b.gsub!('#%',';;;')
-                       b.gsub!('===','#%')
-                       k,v=b.split('=')
-                       tags[k.gsub('#%','=')]=v.gsub('#%','=')
-               end
-               tags
-       end
+def readwayquery(id)
+  ActiveRecord::Base.connection.select_all "SELECT n1.latitude*0.0000001 AS lat1,n1.longitude*0.0000001 AS long1,n1.id AS id1,n1.tags as tags1, "+
+      "                  n2.latitude*0.0000001 AS lat2,n2.longitude*0.0000001 AS long2,n2.id AS id2,n2.tags as tags2,segment_id "+
+      "    FROM current_way_segments,current_segments,current_nodes AS n1,current_nodes AS n2 "+
+      "   WHERE current_way_segments.id=#{id} "+
+      "     AND segment_id=current_segments.id "+
+      "     AND current_segments.visible=1 "+
+      "     AND n1.id=node_a AND n2.id=node_b "+
+      "     AND n1.visible=1 AND n2.visible=1 "+
+      "   ORDER BY sequence_id"
+end
 
-       def array2tag(a)
-               str=''
-               a.each do |k,v|
-                       if v=='' then next end
-                       if v[0,6]=='(type ' then next end
-                       if str!='' then str+=';' end
-                       str+=k.gsub(';',';;;').gsub('=','===')+'='+v.gsub(';',';;;').gsub('=','===')
-               end
-               str
-       end
-       
-       def getuserid(token)
-               token=sqlescape(token)
-               if (token=~/^(.+)\+(.+)$/) then
-                       return ActiveRecord::Base.connection.select_value("SELECT id FROM users WHERE active=1 AND timeout>NOW() AND email='#{$1}' AND pass_crypt=MD5('#{$2}')")
-               else
-                       return ActiveRecord::Base.connection.select_value("SELECT id FROM users WHERE active=1 AND timeout>NOW() AND token='#{token}'")
-               end
-       end
-       
+def createuniquesegments(way,uqs_name,seglist)
+  # Finds segments which appear in (previous version of) this way and no other
+  sql=<<-EOF
+      CREATE TEMPORARY TABLE #{uqs_name}
+              SELECT a.segment_id
+                FROM (SELECT DISTINCT segment_id FROM current_way_segments 
+                  WHERE id = #{way}) a
+             LEFT JOIN current_way_segments b 
+                ON b.segment_id = a.segment_id
+                 AND b.id != #{way}
+               WHERE b.segment_id IS NULL
+    EOF
+  if (seglist!='') then sql+=" AND a.segment_id NOT IN (#{seglist})" end
+  ActiveRecord::Base.connection.execute(sql)
+end
 
+def createuniquenodes(uqs_name,uqn_name)
+       # Finds nodes which appear in uniquesegments but no other segments
+       sql=<<-EOF
+       CREATE TEMPORARY TABLE #{uqn_name}
+          SELECT DISTINCT node_id
+          FROM (SELECT cn.id AS node_id
+                FROM current_nodes AS cn,
+                     current_segments AS cs,
+                     #{uqs_name} AS us
+                WHERE cs.id=us.segment_id
+                  AND cn.id=cs.node_a) AS n
+          LEFT JOIN current_segments AS cs2 ON node_id=cs2.node_a AND cs2.visible=1
+          LEFT JOIN current_segments AS cs3 ON node_id=cs3.node_b AND cs3.visible=1
+          WHERE cs2.node_a IS NULL
+            AND cs3.node_b IS NULL
+       EOF
+       ActiveRecord::Base.connection.execute(sql)
+       sql=<<-EOF
+       INSERT INTO #{uqn_name}
+          SELECT DISTINCT node_id
+          FROM (SELECT cn.id AS node_id
+                FROM current_nodes AS cn,
+                     current_segments AS cs,
+                     #{uqs_name} AS us
+                WHERE cs.id=us.segment_id
+                  AND cn.id=cs.node_b) AS n
+          LEFT JOIN current_segments AS cs2 ON node_id=cs2.node_a AND cs2.visible=1
+          LEFT JOIN current_segments AS cs3 ON node_id=cs3.node_b AND cs3.visible=1
+          WHERE cs2.node_a IS NULL
+            AND cs3.node_b IS NULL
+       EOF
+       ActiveRecord::Base.connection.execute(sql)
+end
 
-       # ====================================================================
-       # AMF read subroutines
-       
-       # ----- getint          return two-byte integer
-       # ----- getlong         return four-byte long
-       # ----- getstring       return string with two-byte length
-       # ----- getdouble       return eight-byte double-precision float
-       # ----- getobject       return object/hash
-       # ----- getarray        return numeric array
-       
-       def getint(s)
-               s.getc*256+s.getc
-       end
-       
-       def getlong(s)
-               ((s.getc*256+s.getc)*256+s.getc)*256+s.getc
-       end
-       
-       def getstring(s)
-               len=s.getc*256+s.getc
-               s.read(len)
-       end
-       
-       def getdouble(s)
-               a=s.read(8).unpack('G')                 # G big-endian, E little-endian
-               a[0]
-       end
-       
-       def getarray(s)
-               len=getlong(s)
-               arr=[]
-               for i in (0..len-1)
-                       arr[i]=getvalue(s)
-               end
-               arr
-       end
-       
-       def getobject(s)
-               arr={}
-               while (key=getstring(s))
-                       if (key=='') then break end
-                       arr[key]=getvalue(s)
-               end
-               s.getc          # skip the 9 'end of object' value
-               arr
-       end
-       
-       # ----- getvalue        parse and get value
-       
-       def getvalue(s)
-               case s.getc
-                       when 0; return getdouble(s)                     # number
-                       when 1; return s.getc                           # boolean
-                       when 2; return getstring(s)                     # string
-                       when 3; return getobject(s)                     # object/hash
-                       when 5; return nil                                      # null
-                       when 6; return nil                                      # undefined
-                       when 8; s.read(4)                                       # mixedArray
-                                       return getobject(s)                     #  |
-                       when 10;return getarray(s)                      # array
-                       else;   return nil                                      # error
-               end
-       end
+def sqlescape(a)
+  a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
+end
 
-       # ====================================================================
-       # AMF write subroutines
-       
-       # ----- putdata         envelope data into AMF writeable form
-       # ----- encodevalue     pack variables as AMF
-       
-       def putdata(index,n)
-               d =encodestring(index+"/onResult")
-               d+=encodestring("null")
-               d+=[-1].pack("N")
-               d+=encodevalue(n)
-       end
-       
-       def encodevalue(n)
-               case n.class.to_s
-                       when 'Array'
-                               a=10.chr+encodelong(n.length)
-                               n.each do |b|
-                                       a+=encodevalue(b)
-                               end
-                               a
-                       when 'Hash'
-                               a=3.chr
-                               n.each do |k,v|
-                                       a+=encodestring(k)+encodevalue(v)
-                               end
-                               a+0.chr+0.chr+9.chr
-                       when 'String'
-                               2.chr+encodestring(n)
-                       when 'Bignum','Fixnum','Float'
-                               0.chr+encodedouble(n)
-                       when 'NilClass'
-                               5.chr
-                       else
-                               RAILS_DEFAULT_LOGGER.error("Unexpected Ruby type for AMF conversion: "+n.class.to_s)
-               end
-       end
-       
-       # ----- encodestring    encode string with two-byte length
-       # ----- encodedouble    encode number as eight-byte double precision float
-       # ----- encodelong              encode number as four-byte long
-       
-       def encodestring(n)
-               a,b=n.size.divmod(256)
-               a.chr+b.chr+n
-       end
-       
-       def encodedouble(n)
-               [n].pack('G')
-       end
-       
-       def encodelong(n)
-               [n].pack('N')
-       end
-       
-       # ====================================================================
-       # Co-ordinate conversion
-       
-       def lat2coord(a,basey,masterscale)
-               -(lat2y(a)-basey)*masterscale+250
-       end
-       
-       def long2coord(a,baselong,masterscale)
-               (a-baselong)*masterscale+350
-       end
-       
-       def lat2y(a)
-               180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
-       end
-       
-       def coord2lat(a,masterscale,basey)
-               y2lat((a-250)/-masterscale+basey)
-       end
-       
-       def coord2long(a,masterscale,baselong)
-               (a-350)/masterscale+baselong
-       end
-       
-       def y2lat(a)
-               180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
-       end
+def tag2array(a)
+  tags={}
+  a.gsub(';;;','#%').split(';').each do |b|
+    b.gsub!('#%',';;;')
+    b.gsub!('===','#%')
+    k,v=b.split('=')
+    if k.nil? then k='' end
+    if v.nil? then v='' end
+    tags[k.gsub('#%','=')]=v.gsub('#%','=')
+  end
+  tags
+end
+
+def array2tag(a)
+  str=''
+  a.each do |k,v|
+    if v=='' then next end
+    if v[0,6]=='(type ' then next end
+    if str!='' then str+=';' end
+    str+=k.gsub(';',';;;').gsub('=','===')+'='+v.gsub(';',';;;').gsub('=','===')
+  end
+  str
+end
+
+def getuserid(token)
+  if (token =~ /^(.+)\+(.+)$/) then
+    user = User.authenticate(:username => $1, :password => $2)
+  else
+    user = User.authenticate(:token => token)
+  end
+
+  return user ? user.id : nil;
+end
 
 
+
+# ====================================================================
+# AMF read subroutines
+
+# -----        getint          return two-byte integer
+# -----        getlong         return four-byte long
+# -----        getstring       return string with two-byte length
+# ----- getdouble      return eight-byte double-precision float
+# ----- getobject      return object/hash
+# ----- getarray       return numeric array
+
+def getint(s)
+  s.getc*256+s.getc
+end
+
+def getlong(s)
+  ((s.getc*256+s.getc)*256+s.getc)*256+s.getc
+end
+
+def getstring(s)
+  len=s.getc*256+s.getc
+  s.read(len)
+end
+
+def getdouble(s)
+  a=s.read(8).unpack('G')                      # G big-endian, E little-endian
+  a[0]
+end
+
+def getarray(s)
+  len=getlong(s)
+  arr=[]
+  for i in (0..len-1)
+    arr[i]=getvalue(s)
+  end
+  arr
+end
+
+def getobject(s)
+  arr={}
+  while (key=getstring(s))
+    if (key=='') then break end
+    arr[key]=getvalue(s)
+  end
+  s.getc               # skip the 9 'end of object' value
+  arr
+end
+
+# -----        getvalue        parse and get value
+
+def getvalue(s)
+  case s.getc
+  when 0;      return getdouble(s)                     # number
+  when 1;      return s.getc                           # boolean
+  when 2;      return getstring(s)                     # string
+  when 3;      return getobject(s)                     # object/hash
+  when 5;      return nil                                      # null
+  when 6;      return nil                                      # undefined
+  when 8;      s.read(4)                                       # mixedArray
+                   return getobject(s)                 #  |
+  when 10;     return getarray(s)                      # array
+  else;                return nil                                      # error
+  end
+end
+
+# ====================================================================
+# AMF write subroutines
+
+# -----        putdata         envelope data into AMF writeable form
+# -----        encodevalue     pack variables as AMF
+
+def putdata(index,n)
+  d =encodestring(index+"/onResult")
+  d+=encodestring("null")
+  d+=[-1].pack("N")
+  d+=encodevalue(n)
+end
+
+def encodevalue(n)
+  case n.class.to_s
+  when 'Array'
+    a=10.chr+encodelong(n.length)
+    n.each do |b|
+      a+=encodevalue(b)
+    end
+    a
+  when 'Hash'
+    a=3.chr
+    n.each do |k,v|
+      a+=encodestring(k)+encodevalue(v)
+    end
+    a+0.chr+0.chr+9.chr
+  when 'String'
+    2.chr+encodestring(n)
+  when 'Bignum','Fixnum','Float'
+    0.chr+encodedouble(n)
+  when 'NilClass'
+    5.chr
+  else
+    RAILS_DEFAULT_LOGGER.error("Unexpected Ruby type for AMF conversion: "+n.class.to_s)
+  end
+end
+
+# -----        encodestring    encode string with two-byte length
+# -----        encodedouble    encode number as eight-byte double precision float
+# -----        encodelong              encode number as four-byte long
+
+def encodestring(n)
+  a,b=n.size.divmod(256)
+  a.chr+b.chr+n
+end
+
+def encodedouble(n)
+  [n].pack('G')
+end
+
+def encodelong(n)
+  [n].pack('N')
+end
+
+# ====================================================================
+# Co-ordinate conversion
+
+def lat2coord(a,basey,masterscale)
+  -(lat2y(a)-basey)*masterscale+250
+end
+
+def long2coord(a,baselong,masterscale)
+  (a-baselong)*masterscale+350
+end
+
+def lat2y(a)
+  180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
+end
+
+def coord2lat(a,masterscale,basey)
+  y2lat((a-250)/-masterscale+basey)
+end
+
+def coord2long(a,masterscale,baselong)
+  (a-350)/masterscale+baselong
+end
+
+def y2lat(a)
+  180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
+end
+
 end