]> git.openstreetmap.org Git - rails.git/blobdiff - app/controllers/amf_controller.rb
Update to use libxml 1.0.0 gem.
[rails.git] / app / controllers / amf_controller.rb
index 921f213c545f347231b544523b4ef8ecf2b799e5..febc4db68cc6a1464e02c00bd504e739f4a587fd 100644 (file)
+# amf_controller is a semi-standalone API for Flash clients, particularly 
+# Potlatch. All interaction between Potlatch (as a .SWF application) and the 
+# OSM database takes place using this controller. Messages are 
+# encoded in the Actionscript Message Format (AMF).
+#
+# Helper functions are in /lib/potlatch.
+#
+# Author::     editions Systeme D / Richard Fairhurst 2004-2008
+# Licence::    public domain.
+#
+# == General structure
+#
+# Apart from the amf_read and amf_write methods (which distribute the requests
+# from the AMF message), each method generally takes arguments in the order 
+# they were sent by the Potlatch SWF. Do not assume typing has been preserved. 
+# Methods all return an array to the SWF.
+# 
+# == Debugging
+# 
+# Any method that returns a status code (0 for ok) can also send:
+#      return(-1,"message")            <-- just puts up a dialogue
+#      return(-2,"message")            <-- also asks the user to e-mail me
+# 
+# To write to the Rails log, use RAILS_DEFAULT_LOGGER.info("message").
+
 class AmfController < ApplicationController
-#=begin
   require 'stringio'
 
-  # to log:
-  # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
+  include Potlatch
 
-  # ====================================================================
-  # Main AMF handler
-  
-  # ---- talk  process AMF request
+  session :off
+  before_filter :check_write_availability
 
-  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
+  # Main AMF handlers: process the raw AMF string (using AMF library) and
+  # calls each action (private method) accordingly.
+  # ** FIXME: refactor to reduce duplication of code across read/write
+  
+  def amf_read
+       req=StringIO.new(request.raw_post+0.chr)# Get POST data as request
+                                                                                       # (cf http://www.ruby-forum.com/topic/122163)
+       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
+       headers=AMF.getint(req)                                 # Read number of headers
+
+       headers.times do                                                # Read each header
+         name=AMF.getstring(req)                               #  |
+         req.getc                                                              #  | skip boolean
+         value=AMF.getvalue(req)                               #  |
+         header["name"]=value                                  #  |
+       end
+
+       bodies=AMF.getint(req)                                  # Read number of bodies
+       bodies.times do                                                 # Read each body
+         message=AMF.getstring(req)                    #  | get message name
+         index=AMF.getstring(req)                              #  | get index in response sequence
+         bytes=AMF.getlong(req)                                #  | get total size in bytes
+         args=AMF.getvalue(req)                                #  | get response (probably an array)
+
+         case message
+               when 'getpresets';                      results[index]=AMF.putdata(index,getpresets())
+               when 'whichways';                       results[index]=AMF.putdata(index,whichways(*args))
+               when 'whichways_deleted';       results[index]=AMF.putdata(index,whichways_deleted(*args))
+               when 'getway';                          results[index]=AMF.putdata(index,getway(args[0].to_i))
+               when 'getrelation';                     results[index]=AMF.putdata(index,getrelation(args[0].to_i))
+               when 'getway_old';                      results[index]=AMF.putdata(index,getway_old(args[0].to_i,args[1].to_i))
+               when 'getway_history';          results[index]=AMF.putdata(index,getway_history(args[0].to_i))
+               when 'getnode_history';         results[index]=AMF.putdata(index,getnode_history(args[0].to_i))
+               when 'findrelations';           results[index]=AMF.putdata(index,findrelations(*args))
+               when 'getpoi';                          results[index]=AMF.putdata(index,getpoi(*args))
+         end
+       end
+    sendresponse(results)
+  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))
-               end
-       end
+  def amf_write
+       req=StringIO.new(request.raw_post+0.chr)
+       req.read(2)
+       results={}
+       renumberednodes={}                                              # Shared across repeated putways
+       renumberedways={}                                               # Shared across repeated putways
+
+       headers=AMF.getint(req)                                 # Read number of headers
+       headers.times do                                                # Read each header
+         name=AMF.getstring(req)                               #  |
+         req.getc                                                              #  | skip boolean
+         value=AMF.getvalue(req)                               #  |
+         header["name"]=value                                  #  |
+       end
+
+       bodies=AMF.getint(req)                                  # Read number of bodies
+       bodies.times do                                                 # Read each body
+         message=AMF.getstring(req)                    #  | get message name
+         index=AMF.getstring(req)                              #  | get index in response sequence
+         bytes=AMF.getlong(req)                                #  | get total size in bytes
+         args=AMF.getvalue(req)                                #  | get response (probably an array)
+
+         case message
+               when 'putway';                          r=putway(renumberednodes,*args)
+                                                                       renumberednodes=r[3]
+                                                                       if r[1] != r[2]
+                                                                         renumberedways[r[1]] = r[2]
+                                                                       end
+                                                                       results[index]=AMF.putdata(index,r)
+               when 'putrelation';                     results[index]=AMF.putdata(index,putrelation(renumberednodes, renumberedways, *args))
+               when 'deleteway';                       results[index]=AMF.putdata(index,deleteway(args[0],args[1].to_i))
+               when 'putpoi';                          results[index]=AMF.putdata(index,putpoi(*args))
+         end
+       end
+    sendresponse(results)
+  end
 
-       # ------------------
-       # Write out response
+  private
 
-       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
+  # Return presets (default tags, localisation etc.):
+  # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.
 
+  def getpresets() #:doc:
+       return POTLATCH_PRESETS
   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|
-
-               # 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,horse=yes,bicycle=yes
-byway: highway=byway,foot=yes,horse=yes,bicycle=yes,motorcar=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
-
-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
-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
-               [presets,presetmenus,presetnames]
-       end
+  # Find all the ways, POI nodes (i.e. not part of ways), and relations
+  # in a given bounding box. Nodes are returned in full; ways and relations 
+  # are IDs only. 
 
-       # ----- 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
-               }
-
-               pointlist=ActiveRecord::Base.connection.select_all("SELECT current_nodes.id,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 (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+") "+
-                        "   AND cs1.id IS NULL AND cs2.id IS NULL "+
-                        "   AND current_nodes.visible=1")
-               points=[]
-               pointlist.each {|a|
-                       points<<[a['id'],tag2array(a['tags'])]
-               }
-               [ways,points]
-       end
+  def whichways(xmin, ymin, xmax, ymax) #:doc:
+       enlarge = [(xmax-xmin)/8,0.01].min
+       xmin -= enlarge; ymin -= enlarge
+       xmax += enlarge; ymax += enlarge
 
-       # ----- 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
+       if POTLATCH_USE_SQL then
+         way_ids = sql_find_way_ids_in_area(xmin, ymin, xmax, ymax)
+         points = sql_find_pois_in_area(xmin, ymin, xmax, ymax)
+         relation_ids = sql_find_relations_in_area_and_ways(xmin, ymin, xmax, ymax, way_ids)
+       else
+         # find the way ids in an area
+         nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => "current_nodes.visible = 1", :include => :ways)
+         way_ids = nodes_in_area.collect { |node| node.way_ids }.flatten.uniq
 
-               # -- 4. get version by inserting new row into ways
+         # find the node ids in an area that aren't part of ways
+         nodes_not_used_in_area = nodes_in_area.select { |node| node.ways.empty? }
+         points = nodes_not_used_in_area.collect { |n| [n.id, n.lon, n.lat, n.tags_as_hash] }
 
-               version=ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},1)")
+         # find the relations used by those nodes and ways
+         relations = Relation.find_for_nodes(nodes_in_area.collect { |n| n.id }, :conditions => "visible = 1") +
+                  Relation.find_for_ways(way_ids, :conditions => "visible = 1")
+         relation_ids = relations.collect { |relation| relation.id }.uniq
+       end
 
-               # -- 5. compare nodes and update xmin,xmax,ymin,ymax
+       [way_ids, points, relation_ids]
+  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
+  # Find deleted ways in current bounding box (similar to whichways, but ways
+  # with a deleted node only - not POIs or relations).
 
-               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 whichways_deleted(xmin, ymin, xmax, ymax) #:doc:
+       xmin -= 0.01; ymin -= 0.01
+       xmax += 0.01; ymax += 0.01
 
-               # -- 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}") }
+       nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => "current_nodes.visible = 0 AND current_ways.visible = 0", :include => :ways_via_history)
+       way_ids = nodes_in_area.collect { |node| node.ways_via_history_ids }.flatten.uniq
 
-               if seglist!='' then
-                       ActiveRecord::Base.connection.update("UPDATE current_segments SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id IN (#{seglist})")
-               end
+       [way_ids]
+  end
 
+  # Get a way including nodes and tags.
+  # Returns 0 (success), a Potlatch-style array of points, and a hash of tags.
+
+  def getway(wayid) #:doc:
+       if POTLATCH_USE_SQL then
+         points = sql_get_nodes_in_way(wayid)
+         tags = sql_get_tags_in_way(wayid)
+       else
+         # Ideally we would do ":include => :nodes" here but if we do that
+         # then rails only seems to return the first copy of a node when a
+         # way includes a node more than once
+         way = Way.find(wayid)
+         points = way.nodes.collect do |node|
+               nodetags=node.tags_as_hash
+               nodetags.delete('created_by')
+               [node.lon, node.lat, node.id, nodetags]
+         end
+         tags = way.tags
+       end
+
+       [wayid, points, tags]
+  end
 
-               # -- 6.ii insert new way segments
+  # Get an old version of a way, and all constituent nodes.
+  #
+  # For undelete (version=0), always uses the most recent version of each node, 
+  # even if it's moved.  For revert (version=1+), uses the node in existence 
+  # at the time, generating a new id if it's still visible and has been moved/
+  # retagged.
 
-               createuniquesegments(way,db_uqs)
+  def getway_old(id, version) #:doc:
+       if version < 0
+         old_way = OldWay.find(:first, :conditions => ['visible = 1 AND id = ?', id], :order => 'version DESC')
+         points = old_way.get_nodes_undelete
+       else
+         old_way = OldWay.find(:first, :conditions => ['id = ? AND version = ?', id, version])
+         points = old_way.get_nodes_revert
+       end
 
-               # 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}")
+       old_way.tags['history'] = "Retrieved from v#{old_way.version}"
 
-               #               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)
-
-               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})
-               EOF
-               ActiveRecord::Base.connection.update(sql)
-       
-               #               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 
-                          AND (cs.timestamp!=#{db_now} OR cs.user_id!=#{uid})
-               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}")
-
-               #               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)+"')"
-               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"
-       end
+       [0, id, points, old_way.tags, old_way.version]
+  end
+  
+  # Find history of a way. Returns 'way', id, and 
+  # an array of previous versions.
 
-       def createuniquesegments(way,uqs_name)
-               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
-               ActiveRecord::Base.connection.execute(sql)
+  def getway_history(wayid) #:doc:
+       history = Way.find(wayid).old_ways.reverse.collect do |old_way|
+         user = old_way.user.data_public? ? old_way.user.display_name : 'anonymous'
+         uid  = old_way.user.data_public? ? old_way.user.id : 0
+         [old_way.version, old_way.timestamp.strftime("%d %b %Y, %H:%M"), old_way.visible ? 1 : 0, user, uid]
        end
-       
 
-       def sqlescape(a)
-               a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
-       end
+       ['way',wayid,history]
+  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
+  # Find history of a node. Returns 'node', id, and 
+  # an array of previous versions.
 
-       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
+  def getnode_history(nodeid) #:doc:
+       history = Node.find(nodeid).old_nodes.reverse.collect do |old_node|
+         user = old_node.user.data_public? ? old_node.user.display_name : 'anonymous'
+         uid  = old_node.user.data_public? ? old_node.user.id : 0
+         [old_node.timestamp.to_i, old_node.timestamp.strftime("%d %b %Y, %H:%M"), old_node.visible ? 1 : 0, user, uid]
        end
-       
 
+       ['node',nodeid,history]
+  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
+  # Get a relation with all tags and members.
+  # Returns:
+  # 0. relation id,
+  # 1. hash of tags,
+  # 2. list of members.
+  
+  def getrelation(relid) #:doc:
+       rel = Relation.find(relid)
+
+       [relid, rel.tags, rel.members]
+  end
+
+  # Find relations with specified name/id.
+  # Returns array of relations, each in same form as getrelation.
+  
+  def findrelations(searchterm)
+       rels = []
+       if searchterm.to_i>0 then
+         rel = Relation.find(searchterm.to_i)
+         if rel and rel.visible then
+           rels.push([rel.id, rel.tags, rel.members])
+         end
+       else
+         RelationTag.find(:all, :limit => 11, :conditions => ["match(v) against (?)", searchterm] ).each do |t|
+               if t.relation.visible then
+             rels.push([t.relation.id, t.relation.tags, t.relation.members])
+           end
+         end
+       end
+       rels
+  end
+
+  # Save a relation.
+  # Returns
+  # 0. 0 (success),
+  # 1. original relation id (unchanged),
+  # 2. new relation id.
+
+  def putrelation(renumberednodes, renumberedways, usertoken, relid, tags, members, visible) #:doc:
+       uid = getuserid(usertoken)
+       if !uid then return -1,"You are not logged in, so the relation could not be saved." end
+
+       relid = relid.to_i
+       visible = visible.to_i
+
+       # create a new relation, or find the existing one
+       if relid <= 0
+         rel = Relation.new
+       else
+         rel = Relation.find(relid)
+       end
+
+       # check the members are all positive, and correctly type
+       typedmembers = []
+       members.each do |m|
+         mid = m[1].to_i
+         if mid < 0
+               mid = renumberednodes[mid] if m[0] == 'node'
+               mid = renumberedways[mid] if m[0] == 'way'
+         end
+      if mid
+           typedmembers << [m[0], mid, m[2]]
+         end
+       end
+
+       # assign new contents
+       rel.members = typedmembers
+       rel.tags = tags
+       rel.visible = visible
+       rel.user_id = uid
+
+       # check it then save it
+       # BUG: the following is commented out because it always fails on my
+       #  install. I think it's a Rails bug.
+
+       #if !rel.preconditions_ok?
+       #  return -2, "Relation preconditions failed"
+       #else
+         rel.save_with_history!
+       #end
+
+       [0, relid, rel.id]
+  end
+
+  # Save a way to the database, including all nodes. Any nodes in the previous
+  # version and no longer used are deleted.
+  # 
+  # Returns:
+  # 0. '0' (code for success),
+  # 1. original way id (unchanged),
+  # 2. new way id,
+  # 3. hash of renumbered nodes (old id=>new id)
+
+  def putway(renumberednodes, usertoken, originalway, points, attributes) #:doc:
+
+       # -- Initialise and carry out checks
        
-       def getdouble(s)
-               a=s.read(8).unpack('G')                 # G big-endian, E little-endian
-               a[0]
+       uid = getuserid(usertoken)
+       if !uid then return -1,"You are not logged in, so the way could not be saved." end
+
+       originalway = originalway.to_i
+
+       points.each do |a|
+         if a[2] == 0 or a[2].nil? then return -2,"Server error - node with id 0 found in way #{originalway}." end
+         if a[1] == 90 then return -2,"Server error - node with lat -90 found in way #{originalway}." end
        end
-       
-       def getarray(s)
-               len=getlong(s)
-               arr=[]
-               for i in (0..len-1)
-                       arr[i]=getvalue(s)
-               end
-               arr
+
+       if points.length < 2 then return -2,"Server error - way is only #{points.length} points long." end
+
+       # -- Get unique nodes
+
+       if originalway < 0
+         way = Way.new
+         uniques = []
+       else
+         way = Way.find(originalway)
+         uniques = way.unshared_node_ids
        end
-       
-       def getobject(s)
-               arr={}
-               while (key=getstring(s))
-                       if (key=='') then break end
-                       arr[key]=getvalue(s)
+
+       # -- Compare nodes and save changes to any that have changed
+
+       nodes = []
+
+       points.each do |n|
+         lon = n[0].to_f
+         lat = n[1].to_f
+         id = n[2].to_i
+         savenode = false
+
+         if renumberednodes[id]
+           id = renumberednodes[id]
+         elsif id < 0
+               # Create new node
+               node = Node.new
+               savenode = true
+         else
+               node = Node.find(id)
+               nodetags=node.tags_as_hash
+               nodetags.delete('created_by')
+               if !fpcomp(lat, node.lat) or !fpcomp(lon, node.lon) or
+                  n[4] != nodetags or !node.visible?
+                 savenode = true
                end
-               s.getc          # skip the 9 'end of object' value
-               arr
+         end
+
+         if savenode
+               node.user_id = uid
+           node.lat = lat
+        node.lon = lon
+           node.tags = Tags.join(n[4])
+           node.visible = true
+           node.save_with_history!
+
+               if id != node.id
+                 renumberednodes[id] = node.id
+                 id = node.id
+           end
+         end
+
+         uniques = uniques - [id]
+         nodes.push(id)
        end
+
+       # -- Save revised way
+
+       way.tags = attributes
+       way.nds = nodes
+       way.user_id = uid
+       way.visible = true
+       way.save_with_history!
+
+       # -- Delete any unique nodes
        
-       # ----- 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
+       uniques.each do |n|
+         deleteitemrelations(n, 'node')
+
+         node = Node.find(n)
+         node.user_id = uid
+         node.visible = false
+         node.save_with_history!
        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)
+       [0, originalway, way.id, renumberednodes]
+  end
+
+  # Save POI to the database.
+  # Refuses save if the node has since become part of a way.
+  # Returns:
+  # 0. 0 (success),
+  # 1. original node id (unchanged),
+  # 2. new node id.
+
+  def putpoi(usertoken, id, lon, lat, tags, visible) #:doc:
+       uid = getuserid(usertoken)
+       if !uid then return -1,"You are not logged in, so the point could not be saved." end
+
+       id = id.to_i
+       visible = (visible.to_i == 1)
+
+       if id > 0 then
+         node = Node.find(id)
+
+         if !visible then
+           unless node.ways.empty? then return -1,"The point has since become part of a way, so you cannot save it as a POI." end
+           deleteitemrelations(id, 'node')
+         end
+       else
+         node = Node.new
        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
+
+       node.user_id = uid
+       node.lat = lat
+       node.lon = lon
+       node.tags = Tags.join(tags)
+       node.visible = visible
+       node.save_with_history!
+
+       [0, id, node.id]
+  end
+
+  # Read POI from database
+  # (only called on revert: POIs are usually read by whichways).
+  #
+  # Returns array of id, long, lat, hash of tags.
+
+  def getpoi(id,timestamp) #:doc:
+       if timestamp>0 then
+         n = OldNode.find(id, :conditions=>['UNIX_TIMESTAMP(timestamp)=?',timestamp])
+       else
+         n = Node.find(id)
        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
+
+       if n
+         return [n.id, n.lon, n.lat, n.tags_as_hash]
+       else
+         return [nil, nil, nil, '']
        end
-       
-       def encodedouble(n)
-               [n].pack('G')
+  end
+
+  # Delete way and all constituent nodes. Also removes from any relations.
+  # Returns 0 (success), unchanged way id.
+
+  def deleteway(usertoken, way_id) #:doc:
+       uid = getuserid(usertoken)
+       if !uid then return -1,"You are not logged in, so the way could not be deleted." end
+
+       # FIXME: would be good not to make two history entries when removing
+       #                two nodes from the same relation
+       user = User.find(uid)
+       way = Way.find(way_id)
+       way.unshared_node_ids.each do |n|
+         deleteitemrelations(n, 'node')
        end
-       
-       def encodelong(n)
-               [n].pack('N')
+       deleteitemrelations(way_id, 'way')
+
+       way.delete_with_relations_and_nodes_and_history(user)  
+
+       [0, way_id]
+  end
+
+
+  # ====================================================================
+  # Support functions
+
+  # Remove a node or way from all relations
+
+  def deleteitemrelations(objid, type) #:doc:
+       relations = RelationMember.find(:all, 
+                                                                       :conditions => ['member_type = ? and member_id = ?', type, objid], 
+                                                                       :include => :relation).collect { |rm| rm.relation }.uniq
+
+       relations.each do |rel|
+         rel.members.delete_if { |x| x[0] == type and x[1] == objid }
+         rel.save_with_history!
        end
-       
-       # ====================================================================
-       # Co-ordinate conversion
-       
-       def lat2coord(a,basey,masterscale)
-               -(lat2y(a)-basey)*masterscale+250
+  end
+
+  # Break out node tags into a hash
+  # (should become obsolete as of API 0.6)
+
+  def tagstring_to_hash(a) #:doc:
+       tags={}
+       Tags.split(a) do |k, v|
+         tags[k]=v
        end
-       
-       def long2coord(a,baselong,masterscale)
-               (a-baselong)*masterscale+350
+       tags
+  end
+
+  # Authenticate token
+  # (could be removed if no-one uses the username+password form)
+
+  def getuserid(token) #:doc:
+       if (token =~ /^(.+)\+(.+)$/) then
+         user = User.authenticate(:username => $1, :password => $2)
+       else
+         user = User.authenticate(:token => token)
        end
+
+       return user ? user.id : nil;
+  end
+
+  # Compare two floating-point numbers to within 0.0000001
+
+  def fpcomp(a,b) #:doc:
+       return ((a/0.0000001).round==(b/0.0000001).round)
+  end
+
+  # Send AMF response
+  
+  def sendresponse(results)
+       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
+
+
+  # ====================================================================
+  # Alternative SQL queries for getway/whichways
+
+  def sql_find_way_ids_in_area(xmin,ymin,xmax,ymax)
+       sql=<<-EOF
+  SELECT DISTINCT current_way_nodes.id AS wayid
+               FROM current_way_nodes
+  INNER JOIN current_nodes ON current_nodes.id=current_way_nodes.node_id
+  INNER JOIN current_ways  ON current_ways.id =current_way_nodes.id
+          WHERE current_nodes.visible=1 
+                AND current_ways.visible=1 
+                AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
+       EOF
+       return ActiveRecord::Base.connection.select_all(sql).collect { |a| a['wayid'].to_i }
+  end
        
-       def lat2y(a)
-               180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
-       end
+  def sql_find_pois_in_area(xmin,ymin,xmax,ymax)
+       sql=<<-EOF
+                 SELECT current_nodes.id,current_nodes.latitude*0.0000001 AS lat,current_nodes.longitude*0.0000001 AS lon,current_nodes.tags 
+                       FROM current_nodes 
+ LEFT OUTER JOIN current_way_nodes cwn ON cwn.node_id=current_nodes.id 
+                  WHERE current_nodes.visible=1
+                        AND cwn.id IS NULL
+                        AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
+       EOF
+       return ActiveRecord::Base.connection.select_all(sql).collect { |n| [n['id'].to_i,n['lon'].to_f,n['lat'].to_f,tagstring_to_hash(n['tags'])] }
+  end
        
-       def coord2lat(a,masterscale,basey)
-               y2lat((a-250)/-masterscale+basey)
-       end
+  def sql_find_relations_in_area_and_ways(xmin,ymin,xmax,ymax,way_ids)
+       # ** It would be more Potlatchy to get relations for nodes within ways
+       #    during 'getway', not here
+       sql=<<-EOF
+         SELECT DISTINCT cr.id AS relid 
+               FROM current_relations cr
+  INNER JOIN current_relation_members crm ON crm.id=cr.id 
+  INNER JOIN current_nodes cn ON crm.member_id=cn.id AND crm.member_type='node' 
+          WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "cn.")}
+       EOF
+       unless way_ids.empty?
+         sql+=<<-EOF
+          UNION
+         SELECT DISTINCT cr.id AS relid
+               FROM current_relations cr
+  INNER JOIN current_relation_members crm ON crm.id=cr.id
+          WHERE crm.member_type='way' 
+                AND crm.member_id IN (#{way_ids.join(',')})
+         EOF
+       end
+       return ActiveRecord::Base.connection.select_all(sql).collect { |a| a['relid'].to_i }.uniq
+  end
        
-       def coord2long(a,masterscale,baselong)
-               (a-350)/masterscale+baselong
-       end
+  def sql_get_nodes_in_way(wayid)
+       points=[]
+       sql=<<-EOF
+               SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,current_nodes.id,tags 
+                 FROM current_way_nodes,current_nodes 
+                WHERE current_way_nodes.id=#{wayid.to_i} 
+                  AND current_way_nodes.node_id=current_nodes.id 
+                  AND current_nodes.visible=1
+         ORDER BY sequence_id
+         EOF
+       ActiveRecord::Base.connection.select_all(sql).each do |row|
+         nodetags=tagstring_to_hash(row['tags'])
+         nodetags.delete('created_by')
+         points << [row['lon'].to_f,row['lat'].to_f,row['id'].to_i,nodetags]
+       end
+       points
+  end
        
-       def y2lat(a)
-               180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
+  def sql_get_tags_in_way(wayid)
+       tags={}
+       ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_way_tags WHERE id=#{wayid.to_i}").each do |row|
+         tags[row['k']]=row['v']
        end
+       tags
+  end
 
-#=end
 end
+
+# Local Variables:
+# indent-tabs-mode: t
+# tab-width: 4
+# End: