X-Git-Url: https://git.openstreetmap.org/rails.git/blobdiff_plain/ba6b3f355a6cfcb2f3d2c9a0d912ec6249264988..ddd5b4cf19a92582fd114914be5bd5a04d3522a7:/app/controllers/amf_controller.rb

diff --git a/app/controllers/amf_controller.rb b/app/controllers/amf_controller.rb
index 8132b5311..5a8952b0f 100644
--- a/app/controllers/amf_controller.rb
+++ b/app/controllers/amf_controller.rb
@@ -4,8 +4,24 @@ class AmfController < ApplicationController
   session :off
   before_filter :check_write_availability
 
+  # AMF controller for 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).
+  #
+  # Public domain. Set your tab width to 4 to read this document. :)
+  # editions Systeme D / Richard Fairhurst 2004-2008
+  #
+  # All in/out parameters are floats unless explicitly stated.
+  # Note that in getway/getway_old, SWF object name and way id are
+  #Êidentical and one could probably be eliminated.
+  # 
+  # to trap errors (getway_old,putway,putpoi,deleteway only):
+  #   return(-1,"message")		<-- just puts up a dialogue
+  #   return(-2,"message")		<-- also asks the user to e-mail me
   # to log:
-  # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
+  #   RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
 
   # ====================================================================
   # Main AMF handler
@@ -13,9 +29,11 @@ class AmfController < ApplicationController
   # ---- 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
+    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
+    renumberednodes={}							# Shared across repeated putways
 
     # -------------
     # Parse request
@@ -37,14 +55,18 @@ class AmfController < ApplicationController
       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))
+      when 'getpresets';		results[index]=putdata(index,getpresets)
+      when 'whichways';			results[index]=putdata(index,whichways(args))
+      when 'whichways_deleted';	results[index]=putdata(index,whichways_deleted(args))
+      when 'getway';			results[index]=putdata(index,getway(args))
+      when 'getway_old';		results[index]=putdata(index,getway_old(args))
+      when 'getway_history';	results[index]=putdata(index,getway_history(args))
+      when 'putway';			r=putway(args,renumberednodes)
+        renumberednodes=r[3]
+        results[index]=putdata(index,r)
+      when 'deleteway';			results[index]=putdata(index,deleteway(args))
+      when 'putpoi';			results[index]=putdata(index,putpoi(args))
+      when 'getpoi';			results[index]=putdata(index,getpoi(args))
       end
     end
 
@@ -53,138 +75,40 @@ class AmfController < ApplicationController
 
     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
-	}
+    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
+    }
     RAILS_DEFAULT_LOGGER.info("  Response: end")
 
   end
 
   private
 
+
   # ====================================================================
   # Remote calls
 
   # ----- getpresets
-  #	      return presets,presetmenus and presetnames arrays
+  #		  in:   none
+  #		  does: reads tag preset menus, colours, and autocomplete config files
+  #	      out:  [0] presets, [1] presetmenus, [2] presetnames,
+  #				[3] colours, [4] casing, [5] areas, [6] autotags
+  #				(all hashes)
 
   def getpresets
+    RAILS_DEFAULT_LOGGER.info("  Message: getpresets")
+
+    # Read preset menus
     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|
+    #	StringIO.open(txt) do |file|
+    File.open("#{RAILS_ROOT}/config/potlatch/presets.txt") do |file|
       file.each_line {|line|
         t=line.chomp
         if (t=~/(\w+)\/(\w+)/) then
@@ -202,13 +126,51 @@ EOF
         end
       }
     end
-    return [presets,presetmenus,presetnames]
+
+    # Read colours/styling
+    colours={}; casing={}; areas={}
+    File.open("#{RAILS_ROOT}/config/potlatch/colours.txt") do |file|
+      file.each_line {|line|
+        t=line.chomp
+        if (t=~/(\w+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)/) then
+          tag=$1
+          if ($2!='-') then colours[tag]=$2.hex end
+          if ($3!='-') then casing[tag]=$3.hex end
+          if ($4!='-') then areas[tag]=$4.hex end
+        end
+      }
+    end
+
+    # Read auto-complete
+    autotags={}; autotags['point']={}; autotags['way']={}; autotags['POI']={};
+    File.open("#{RAILS_ROOT}/config/potlatch/autocomplete.txt") do |file|
+      file.each_line {|line|
+        t=line.chomp
+        if (t=~/^(\w+)\/(\w+)\s+(.+)$/) then
+          tag=$1; type=$2; values=$3
+          if values=='-' then autotags[type][tag]=[]
+          else autotags[type][tag]=values.split(',').sort.reverse end
+        end
+      }
+    end
+
+    [presets,presetmenus,presetnames,colours,casing,areas,autotags]
   end
 
-  # ----- whichways(left,bottom,right,top)
+  # ----- whichways
   #		  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
+
+  #		  in:   [0] xmin, [1] ymin, [2] xmax, [3] ymax (bbox in degrees)
+  #				[4] baselong (longitude of SWF map origin),
+  #				[5] basey (projected latitude of SWF map origin),
+  #				[6] masterscale (SWF map scale)
+  #		  does: finds all ways and POI nodes in bounding box
+  #		  		at present, instead of using correct (=more complex) SQL to find
+  #		  		corner-crossing ways, it simply enlarges the bounding box
+  #		  out:  [0] array of way ids,
+  #				[1] array of POIs
+  #				(where each POI is an array containing:
+  #				 [0] id, [1] projected long, [2] projected lat, [3] hash of tags)
 
   def whichways(args)
     xmin = args[0].to_f-0.01
@@ -221,89 +183,227 @@ EOF
 
     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 "+
+    waylist = ActiveRecord::Base.connection.select_all("SELECT DISTINCT current_way_nodes.id AS wayid"+
+       "  FROM current_way_nodes,current_nodes,current_ways "+
+       " WHERE current_nodes.id=current_way_nodes.node_id "+
+       "   AND current_nodes.visible=1 "+
+       "   AND current_ways.id=current_way_nodes.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
+    ways = waylist.collect {|a| a['wayid'].to_i } # get an array of way IDs
 
     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 "+
+       "  LEFT OUTER JOIN current_way_nodes cwn ON cwn.node_id=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 cwn.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]
+    [ways,points]
   end
 
-  # ----- getway (objectname, way, baselong, basey, masterscale)
-  #		  returns objectname, array of co-ordinates, attributes,
-  #				  xmin,xmax,ymin,ymax
+  # ----- whichways_deleted
+  #		  return array of deleted ways in current bounding box
+
+  #		  in:	as whichways
+  #		  does: finds all deleted ways with a deleted node in bounding box
+  #		  out:	[0] array of way ids
 
+  def whichways_deleted(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]
+
+    sql=<<-EOF
+     SELECT DISTINCT current_ways.id 
+       FROM current_nodes,way_nodes,current_ways 
+      WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")} 
+      AND way_nodes.node_id=current_nodes.id 
+      AND way_nodes.id=current_ways.id 
+      AND current_nodes.visible=0 
+      AND current_ways.visible=0 
+  EOF
+    waylist = ActiveRecord::Base.connection.select_all(sql)
+    ways = waylist.collect {|a| a['id'].to_i }
+    [ways]
+  end
+
+  # Get a way with all of it's nodes and tags
+  # The input is an array with the following components, in order:
+  # 0. SWF object name (String?) - fuck knows
+  # 1. wayid (String?) - the ID of the way to get
+  # 2. baselong - fuck knows
+  # 3. basey - fuck knows
+  # 4. masterscale - fuck knows
+  #
+  # The output is an array which contains all the nodes (with projected latitude and longitude) and tags for a way (and all the nodes tags). It also has the way's unprojected (WGS84) bbox.
+  #
+  # FIXME: The server really shouldn't be figuring out a ways bounding box and doing projection for potlatch
+  # FIXME: the argument splitting should be done in the 'talk' method, not here
+  #
   def getway(args)
-    objname,wayid,baselong,basey,masterscale=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
+    way = Way.find_eager(wayid)
+    long_array = []
+    lat_array = []
+    points = []
+
+    way.way_nodes.each do |way_node|
+      node = way_node.node # get the node record
+      projected_longitude = node.lon_potlatch(baselong,masterscale) # do projection for potlatch
+      projected_latitude = node.lat_potlatch(basey,masterscale)
+      id = node.id # node ide
+      tags_hash = node.tags_as_hash # hash of tags
+      
+      points << [projected_longitude, projected_latitude, id, nil, tags_hash] # FIXME remove the nil in potlatch. performance matters y'know!
+      long_array << projected_longitude
+      lat_array << projected_latitude
+    end
+
+    [objname,points,way.tags,long_array.min,long_array.max,lat_array.min,lat_array.max]
+  end
+
+  # ----- getway_old
+  #		  returns old version of way
+
+  #		  in:	[0] SWF object name, [1] way id,
+  #				[2] way version to get (or -1 for "last deleted version")
+  #				[3] baselong, [4] basey, [5] masterscale
+  #		  does:	gets old version of way and all constituent nodes
+  #				for undelete, always uses the most recent version of each node
+  #				  (even if it's moved)
+  #				for revert, uses the historic version of each node, but if that node is
+  #				  still visible and has been changed since, generates a new node id
+  #		  out:	[0] 0 (code for success), [1] SWF object name,
+  #				[2] array of points (as getway _except_ [3] is node.visible?, 0 or 1),
+  #				[4] xmin, [5] xmax, [6] ymin, [7] ymax (unprojected bbox),
+  #				[8] way version
+
+  def getway_old(args)
+    RAILS_DEFAULT_LOGGER.info("  Message: getway_old (server is #{SERVER_URL})")
+    #	if SERVER_URL=="www.openstreetmap.org" then return -1,"Revert is not currently enabled on the OpenStreetMap server." end
+
+    objname,wayid,version,baselong,basey,masterscale=args
+    wayid = wayid.to_i
+    version = version.to_i
+    xmin = ymin =  999999
+    xmax = ymax = -999999
+    points=[]
+    if version<0
+      historic=false
+      version=getlastversion(wayid,version)
+    else
+      historic=true
+    end
+    readwayquery_old(wayid,version,historic).each { |row|
+      points<<[long2coord(row['longitude'].to_f,baselong,masterscale),lat2coord(row['latitude'].to_f,basey,masterscale),row['id'].to_i,row['visible'].to_i,tag2array(row['tags'].to_s)]
+      xmin=[xmin,row['longitude'].to_f].min
+      xmax=[xmax,row['longitude'].to_f].max
+      ymin=[ymin,row['latitude' ].to_f].min
+      ymax=[ymax,row['latitude' ].to_f].max
     }
 
+    # get tags from this version
     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'] }
+    attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM way_tags WHERE id=#{wayid} AND version=#{version}"
+    attrlist.each {|a| attributes[a['k'].gsub(':','|')]=a['v'] }
+    attributes['history']="Retrieved from v"+version.to_s
 
-    [objname,points,attributes,xmin,xmax,ymin,ymax]
+    [0,objname,points,attributes,xmin,xmax,ymin,ymax,version]
   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
+  # ----- getway_history
+  #		  find history of a way
 
-  def putway(args)
-    usertoken,originalway,points,attributes,baselong,basey,masterscale=args
+  #		  in:	[0] way id
+  #		  does:	finds history of a way
+  #		  out:	[0] array of previous versions (where each is
+  #					[0] version, [1] db timestamp (string),
+  #					[2] visible 0 or 1,
+  #					[3] username or 'anonymous' (string))
+
+  def getway_history(args)
+    wayid=args[0]
+    history=[]
+    sql=<<-EOF
+  SELECT version,timestamp,visible,display_name,data_public
+    FROM ways,users
+   WHERE ways.id=#{wayid}
+     AND ways.user_id=users.id
+     AND ways.visible=1
+   ORDER BY version DESC
+  EOF
+    histlist=ActiveRecord::Base.connection.select_all(sql)
+    histlist.each { |row|
+      if row['data_public'].to_i==1 then user=row['display_name'] else user='anonymous' end
+      history<<[row['version'],row['timestamp'],row['visible'],user]
+    }
+    [history]
+  end
+
+  # ----- putway
+  #		  saves a way to the database
+
+  #		  in:	[0] user token (string),
+  #				[1] original way id (may be negative), 
+  #				[2] array of points (as getway/getway_old),
+  #				[3] hash of way tags,
+  #				[4] original way version (0 if not a reverted/undeleted way),
+  #				[5] baselong, [6] basey, [7] masterscale
+  #		  does: saves way to the database
+  #				all constituent nodes are created/updated as necessary
+  #				(or deleted if they were in the old version and are otherwise unused)
+  #		  out:	[0] 0 (code for success), [1] original way id (unchanged),
+  #				[2] new way id, [3] hash of renumbered nodes (old id=>new id),
+  #				[4] xmin, [5] xmax, [6] ymin, [7] ymax (unprojected bbox)
+
+  def putway(args,renumberednodes)
+    RAILS_DEFAULT_LOGGER.info("  putway started")
+    usertoken,originalway,points,attributes,oldversion,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
+    if !uid then return -1,"You are not logged in, so the way could not be saved." end
+
+    RAILS_DEFAULT_LOGGER.info("  putway authenticated happily")
+    db_uqn='unin'+(rand*100).to_i.to_s+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'+(rand*100).to_i.to_s+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
+    oldversion=oldversion.to_i
 
     RAILS_DEFAULT_LOGGER.info("  Message: putway, id=#{originalway}")
 
+    # -- Temporary check for null IDs
+
+    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
+    end
+
     # -- 3.	read original way into memory
 
-    xc={}; yc={}; tagc={}; seg={}
+    xc={}; yc={}; tagc={}; vc={}
     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
+      if oldversion==0 then r=readwayquery(way,false)
+      else r=readwayquery_old(way,oldversion,true) end
+      r.each { |row|
+        id=row['id'].to_i
+        if (id>0) then
+          xc[id]=row['longitude'].to_f
+          yc[id]=row['latitude' ].to_f
+          tagc[id]=row['tags']
+          vc[id]=row['visible'].to_i
+        end
       }
       ActiveRecord::Base.connection.update("UPDATE current_ways SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id=#{way}")
     else
@@ -316,10 +416,10 @@ EOF
 
     # -- 5. compare nodes and update xmin,xmax,ymin,ymax
 
-    xmin = ymin = 999999
-    xmax = ymax = -999999
-    insertsql = ''
-    renumberednodes={}
+    xmin=ymin= 999999
+    xmax=ymax=-999999
+    insertsql=''
+    nodelist=[]
 
     points.each_index do |i|
       xs=coord2long(points[i][0],masterscale,baselong)
@@ -328,7 +428,6 @@ EOF
       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
@@ -337,18 +436,20 @@ EOF
       # compare node
       if node<0
         # new node - create
-	if renumberednodes[node.to_s].nil?
+        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})")
+          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
+          nodelist.push(newnode)
           renumberednodes[node.to_s]=newnode.to_s
-	else
+        else
           points[i][2]=renumberednodes[node.to_s].to_i
-	end
+        end
 
       elsif xc.has_key?(node)
+        nodelist.push(node)
         # old node from original way - update
-        if (xs!=xc[node] or ys!=yc[node] or tagstr!=tagc[node])
+        if ((xs/0.0000001).round!=(xc[node]/0.0000001).round or (ys/0.0000001).round!=(yc[node]/0.0000001).round or tagstr!=tagc[node] or vc[node]==0)
           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
@@ -358,64 +459,15 @@ EOF
     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
+    # -- 6a. delete any nodes not in modified way
 
-    #		delete segments from uniquesegments (and not in modified way)
+    createuniquenodes(way,db_uqn,nodelist)	# nodes which appear in this way but no other
 
     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
+  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)
 
@@ -426,26 +478,25 @@ EOF
     EOF
     ActiveRecord::Base.connection.update(sql)
 
-    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
-    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
+    deleteuniquenoderelations(db_uqn,uid,db_now)
+    ActiveRecord::Base.connection.execute("DROP TEMPORARY TABLE #{db_uqn}")
 
-    #		insert new version of route into way_segments
+    #	6b. insert new version of route into way_nodes
 
     insertsql =''
     currentsql=''
     sequence  =1
-    for i in (0..(points.length-2))
-      if (points[i+1][3].to_i==0) then next end
+    points.each do |p|
       if insertsql !='' then insertsql +=',' end
       if currentsql!='' then currentsql+=',' end
-      insertsql +="(#{way},#{points[i+1][5]},#{version})"
-      currentsql+="(#{way},#{points[i+1][5]},#{sequence})"
+      insertsql +="(#{way},#{p[2]},#{sequence},#{version})"
+      currentsql+="(#{way},#{p[2]},#{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}");
+    ActiveRecord::Base.connection.execute("DELETE FROM current_way_nodes WHERE id=#{way}");
+    ActiveRecord::Base.connection.insert( "INSERT INTO         way_nodes (id,node_id,sequence_id,version) VALUES #{insertsql}");
+    ActiveRecord::Base.connection.insert( "INSERT INTO current_way_nodes (id,node_id,sequence_id        ) VALUES #{currentsql}");
 
     # -- 7. insert new way tags
 
@@ -456,108 +507,118 @@ EOF
       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)+"')"
+      insertsql +="(#{way},'"+sqlescape(k.gsub('|',':'))+"','"+sqlescape(v)+"',#{version})"
+      currentsql+="(#{way},'"+sqlescape(k.gsub('|',':'))+"','"+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]
+    [0,originalway,way,renumberednodes,xmin,xmax,ymin,ymax]
   end
 
-  # -----	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
+  # ----- putpoi
+  #		  save POI to the database
+
+  #		  in:	[0] user token (string),
+  #				[1] original node id (may be negative),
+  #			  	[2] projected longitude, [3] projected latitude,
+  #				[4] hash of tags, [5] visible (0 to delete, 1 otherwise), 
+  #				[6] baselong, [7] basey, [8] masterscale
+  #		  does:	saves POI node to the database
+  #				refuses save if the node has since become part of a way
+  #		  out:	[0] 0 (success), [1] original node id (unchanged),
+  #				[2] new node id
 
   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
+    if !uid then return -1,"You are not logged in, so the point could not be saved." end
+
+    db_now='@now'+(rand*100).to_i.to_s+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
+    if visible==0 then
+      # if deleting, check node hasn't become part of a way 
+      inway=ActiveRecord::Base.connection.select_one("SELECT cw.id FROM current_ways cw,current_way_nodes cwn WHERE cw.id=cwn.id AND cw.visible=1 AND cwn.node_id=#{id} LIMIT 1")
+      unless inway.nil? then return -1,"The point has since become part of a way, so you cannot save it as a POI." end
+      deleteitemrelations(id,'node',uid,db_now)
+    end
+
     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
+      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})");
+      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]
+    [0,id,newid]
   end
 
-  # -----	getpoi (id,baselong,basey,masterscale)
-  #			returns id,x,y,tag array
-  
+  # ----- getpoi
+  #		  read POI from database
+  #		  (only called on revert: POIs are usually read by whichways)
+
+  #		  in:	[0] node id, [1] baselong, [2] basey, [3] masterscale
+  #		  does: reads POI
+  #		  out:	[0] id (unchanged), [1] projected long, [2] projected lat,
+  #				[3] hash of tags
+
   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'])]
+    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
 
-  # -----	deleteway (user token, way)
-  #			returns way ID only
+  # ----- deleteway
+  #		  delete way and constituent nodes from database
+
+  #		  in:	[0] user token (string), [1] way id
+  #		  does: deletes way from db and any constituent nodes not used elsewhere
+  #				also removes ways/nodes from any relations they're in
+  #		  out:	[0] 0 (success), [1] way id (unchanged)
 
   def deleteway(args)
     usertoken,way=args
 
     RAILS_DEFAULT_LOGGER.info("  Message: deleteway, id=#{way}")
+    uid=getuserid(usertoken)
+    if !uid then return -1,"You are not logged in, so the way could not be deleted." 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
+    db_uqn='unin'+(rand*100).to_i.to_s+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'+(rand*100).to_i.to_s+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,'')
 
-    # -	delete any otherwise unused segments
+    # - delete any otherwise unused nodes
 
-    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)
+    createuniquenodes(way,db_uqn,[])
 
-    # - delete any unused nodes
-  
-    createuniquenodes(db_uqs,db_uqn)
+    #	unless (preserve.empty?) then
+    #		ActiveRecord::Base.connection.execute("DELETE FROM #{db_uqn} WHERE node_id IN ("+preserve.join(',')+")")
+    #	end
 
     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
+  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)
 
@@ -567,416 +628,352 @@ EOF
        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}")
+
+    deleteuniquenoderelations(db_uqn,uid,db_now)
+    ActiveRecord::Base.connection.execute("DROP TEMPORARY 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_nodes WHERE id=#{way}")
     ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
-	
-    way
-end
+    deleteitemrelations(way,'way',uid,db_now)
+    [0,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_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
-		sql=<<-EOF
-			INSERT INTO segments 
-		   (SELECT * FROM current_segments 
-		     WHERE id IN (#{toreverse.join(',')}))
-		EOF
-		ActiveRecord::Base.connection.insert sql
-	end
-
-	[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
-	}
-	
-	# 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
+  # ====================================================================
+  # Support functions for remote calls
 
+  def readwayquery(id,insistonvisible)
+    sql=<<-EOF
+    SELECT latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,current_nodes.id,tags,visible 
+      FROM current_way_nodes,current_nodes 
+     WHERE current_way_nodes.id=#{id} 
+       AND current_way_nodes.node_id=current_nodes.id 
+  EOF
+    if insistonvisible then sql+=" AND current_nodes.visible=1 " end
+    sql+=" ORDER BY sequence_id"
+    ActiveRecord::Base.connection.select_all(sql)
+  end
 
-# ====================================================================
-# Support functions for remote calls
+  def getlastversion(id,version)
+    row=ActiveRecord::Base.connection.select_one("SELECT version FROM ways WHERE id=#{id} AND visible=1 ORDER BY version DESC LIMIT 1")
+    row['version']
+  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 readwayquery_old(id,version,historic)
+    # Node handling on undelete (historic=false):
+    # - always use the node specified, even if it's moved
 
-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
+    # Node handling on revert (historic=true):
+    # - if it's a visible node, use a new node id (i.e. not mucking up the old one)
+    #   which means the SWF needs to allocate new ids
+    # - if it's an invisible node, we can reuse the old node id
+
+    # get node list from specified version of way,
+    # and the _current_ lat/long/tags of each node
+
+    row=ActiveRecord::Base.connection.select_one("SELECT timestamp FROM ways WHERE version=#{version} AND id=#{id}")
+    waytime=row['timestamp']
+
+    sql=<<-EOF
+  SELECT cn.id,visible,latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,tags 
+    FROM way_nodes wn,current_nodes cn 
+   WHERE wn.version=#{version} 
+     AND wn.id=#{id} 
+     AND wn.node_id=cn.id 
+   ORDER BY sequence_id
+  EOF
+    rows=ActiveRecord::Base.connection.select_all(sql)
+
+    # if historic (full revert), get the old version of each node
+    # - if it's in another way now, generate a new id
+    # - if it's not in another way, use the old ID
+    if historic then
+      rows.each_index do |i|
+        sql=<<-EOF
+    SELECT latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,tags,cwn.id AS currentway 
+      FROM nodes n
+   LEFT JOIN current_way_nodes cwn
+      ON cwn.node_id=n.id
+     WHERE n.id=#{rows[i]['id']} 
+       AND n.timestamp<="#{waytime}" 
+     AND cwn.id!=#{id} 
+     ORDER BY n.timestamp DESC 
+     LIMIT 1
     EOF
-  if (seglist!='') then sql+=" AND a.segment_id NOT IN (#{seglist})" end
-  ActiveRecord::Base.connection.execute(sql)
-end
+        row=ActiveRecord::Base.connection.select_one(sql)
+        unless row.nil? then
+          nx=row['longitude'].to_f
+          ny=row['latitude'].to_f
+          if (row['currentway'] && (nx!=rows[i]['longitude'].to_f or ny!=rows[i]['latitude'].to_f or row['tags']!=rows[i]['tags'])) then rows[i]['id']=-1 end
+          rows[i]['longitude']=nx
+          rows[i]['latitude' ]=ny
+          rows[i]['tags'     ]=row['tags']
+        end
+      end
+    end
+    rows
+  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
+  def createuniquenodes(way,uqn_name,nodelist)
+    # Find nodes which appear in this way but no others
+    sql=<<-EOF
+  CREATE TEMPORARY TABLE #{uqn_name}
+          SELECT a.node_id
+            FROM (SELECT DISTINCT node_id FROM current_way_nodes
+              WHERE id=#{way}) a
+         LEFT JOIN current_way_nodes b
+            ON b.node_id=a.node_id
+             AND b.id!=#{way}
+           WHERE b.node_id IS NULL
+  EOF
+    unless nodelist.empty? then
+      sql+="AND a.node_id NOT IN ("+nodelist.join(',')+")"
+    end
+    ActiveRecord::Base.connection.execute(sql)
+  end
 
-def sqlescape(a)
-  a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
-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('=','===')
+  # ====================================================================
+  # Relations handling
+  # deleteuniquenoderelations(uqn_name,uid,db_now)
+  # deleteitemrelations(way|node,'way'|'node',uid,db_now)
+
+  def deleteuniquenoderelations(uqn_name,uid,db_now)
+    sql=<<-EOF
+  SELECT node_id,cr.id FROM #{uqn_name},current_relation_members crm,current_relations cr 
+   WHERE crm.member_id=node_id 
+     AND crm.member_type='node' 
+     AND crm.id=cr.id 
+     AND cr.visible=1
+  EOF
+
+    relnodes=ActiveRecord::Base.connection.select_all(sql)
+    relnodes.each do |a|
+      removefromrelation(a['node_id'],'node',a['id'],uid,db_now)
+    end
   end
-  str
-end
 
-def getuserid(token)
-  if (token =~ /^(.+)\+(.+)$/) then
-    user = User.authenticate(:username => $1, :password => $2)
-  else
-    user = User.authenticate(:token => token)
+  def deleteitemrelations(objid,type,uid,db_now)
+    sql=<<-EOF
+  SELECT cr.id FROM current_relation_members crm,current_relations cr 
+   WHERE crm.member_id=#{objid} 
+     AND crm.member_type='#{type}' 
+     AND crm.id=cr.id 
+     AND cr.visible=1
+  EOF
+
+    relways=ActiveRecord::Base.connection.select_all(sql)
+    relways.each do |a|
+      removefromrelation(objid,type,a['id'],uid,db_now)
+    end
   end
 
-  return user ? user.id : nil;
-end
+  def removefromrelation(objid,type,relation,uid,db_now)
+    rver=ActiveRecord::Base.connection.insert("INSERT INTO relations (id,user_id,timestamp,visible) VALUES (#{relation},#{uid},#{db_now},1)")
+
+    tagsql=<<-EOF
+  INSERT INTO relation_tags (id,k,v,version) 
+  SELECT id,k,v,#{rver} FROM current_relation_tags 
+   WHERE id=#{relation} 
+  EOF
+    ActiveRecord::Base.connection.insert(tagsql)
+
+    membersql=<<-EOF
+  INSERT INTO relation_members (id,member_type,member_id,member_role,version) 
+  SELECT id,member_type,member_id,member_role,#{rver} FROM current_relation_members 
+   WHERE id=#{relation} 
+     AND (member_id!=#{objid} OR member_type!='#{type}')
+  EOF
+    ActiveRecord::Base.connection.insert(membersql)
+
+    ActiveRecord::Base.connection.update("UPDATE current_relations SET user_id=#{uid},timestamp=#{db_now} WHERE id=#{relation}")
+    ActiveRecord::Base.connection.execute("DELETE FROM current_relation_members WHERE id=#{relation} AND member_type='#{type}' AND member_id=#{objid}")
+  end
 
+  def sqlescape(a)
+    a.gsub(/[\000-\037]/,"").gsub("'","''").gsub(92.chr) {92.chr+92.chr}
+  end
 
+  def tag2array(a)
+    tags={}
+    Tags.split(a) do |k, v|
+      tags[k.gsub(':','|')]=v
+    end
+    tags
+  end
 
-# ====================================================================
-# AMF read subroutines
+  def array2tag(a)
+    tags = []
+    a.each do |k,v|
+      if v=='' then next end
+      if v[0,6]=='(type ' then next end
+      tags << [k.gsub('|',':'), v]
+    end
+    return Tags.join(tags)
+  end
 
-# -----	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 getuserid(token)
+    if (token =~ /^(.+)\+(.+)$/) then
+      user = User.authenticate(:username => $1, :password => $2)
+    else
+      user = User.authenticate(:token => token)
+    end
 
-def getint(s)
-  s.getc*256+s.getc
-end
+    return user ? user.id : nil;
+  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
+  # ====================================================================
+  # 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 getarray(s)
-  len=getlong(s)
-  arr=[]
-  for i in (0..len-1)
-    arr[i]=getvalue(s)
+  def getint(s)
+    s.getc*256+s.getc
   end
-  arr
-end
 
-def getobject(s)
-  arr={}
-  while (key=getstring(s))
-    if (key=='') then break end
-    arr[key]=getvalue(s)
+  def getlong(s)
+    ((s.getc*256+s.getc)*256+s.getc)*256+s.getc
   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
+  def getstring(s)
+    len=s.getc*256+s.getc
+    s.read(len)
   end
-end
 
-# ====================================================================
-# AMF write subroutines
+  def getdouble(s)
+    a=s.read(8).unpack('G')			# G big-endian, E little-endian
+    a[0]
+  end
 
-# -----	putdata		envelope data into AMF writeable form
-# -----	encodevalue	pack variables as AMF
+  def getarray(s)
+    len=getlong(s)
+    arr=[]
+    for i in (0..len-1)
+      arr[i]=getvalue(s)
+    end
+    arr
+  end
 
-def putdata(index,n)
-  d =encodestring(index+"/onResult")
-  d+=encodestring("null")
-  d+=[-1].pack("N")
-  d+=encodevalue(n)
-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
 
-def encodevalue(n)
-  case n.class.to_s
-  when 'Array'
-    a=10.chr+encodelong(n.length)
-    n.each do |b|
-      a+=encodevalue(b)
+  # -----	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
-    a
-  when 'Hash'
-    a=3.chr
-    n.each do |k,v|
-      a+=encodestring(k)+encodevalue(v)
+  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
-    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
+  # -----	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 encodestring(n)
+    a,b=n.size.divmod(256)
+    a.chr+b.chr+n
+  end
 
-def encodedouble(n)
-  [n].pack('G')
-end
+  def encodedouble(n)
+    [n].pack('G')
+  end
 
-def encodelong(n)
-  [n].pack('N')
-end
+  def encodelong(n)
+    [n].pack('N')
+  end
 
-# ====================================================================
-# Co-ordinate conversion
+  # ====================================================================
+  # Co-ordinate conversion
 
-def lat2coord(a,basey,masterscale)
-  -(lat2y(a)-basey)*masterscale+250
-end
+  def lat2coord(a,basey,masterscale)
+    -(lat2y(a)-basey)*masterscale+250
+  end
 
-def long2coord(a,baselong,masterscale)
-  (a-baselong)*masterscale+350
-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 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 coord2lat(a,masterscale,basey)
+    y2lat((a-250)/-masterscale+basey)
+  end
 
-def coord2long(a,masterscale,baselong)
-  (a-350)/masterscale+baselong
-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 y2lat(a)
+    180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
+  end
 
 end