X-Git-Url: https://git.openstreetmap.org/rails.git/blobdiff_plain/a424b6282f1587eb02f2add29b85958a86fc79c1..97726826e1bcdec2369996aa0b1b0db737a58926:/app/controllers/amf_controller.rb

diff --git a/app/controllers/amf_controller.rb b/app/controllers/amf_controller.rb
index 8e23a18cc..70f8f427d 100644
--- a/app/controllers/amf_controller.rb
+++ b/app/controllers/amf_controller.rb
@@ -1,720 +1,609 @@
+# 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 talk method (which distributes 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
   require 'stringio'
 
-  # to log:
-  # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
-
-  # ====================================================================
-  # Main AMF handler
+  include Potlatch
 
-  # ---- talk	process AMF request
+  session :off
+  before_filter :check_write_availability
 
+  # Main AMF handler: processes the raw AMF string (using AMF library) and
+  # calls each action (private method) accordingly.
+  
   def talk
-    req=StringIO.new(request.raw_post)	# Get POST data as request
-    req.read(2)							# Skip version indicator and client ID
-    results={}							# Results of each body
-
-    # -------------
-    # Parse request
-
-    headers=getint(req)					# Read number of headers
-
-    headers.times do				    # Read each header
-      name=getstring(req)				#  |
-      req.getc                 			#  | skip boolean
-      value=getvalue(req)				#  |
-      header["name"]=value				#  |
-    end
-
-    bodies=getint(req)					# Read number of bodies
-    bodies.times do     				# Read each body
-      message=getstring(req)			#  | get message name
-      index=getstring(req)				#  | get index in response sequence
-      bytes=getlong(req)				#  | get total size in bytes
-      args=getvalue(req)				#  | get response (probably an array)
-
-      case message
-      when 'getpresets';	results[index]=putdata(index,getpresets)
-      when 'whichways';		results[index]=putdata(index,whichways(args))
-      when 'getway';		results[index]=putdata(index,getway(args))
-      when 'putway';		results[index]=putdata(index,putway(args))
-      when 'deleteway';		results[index]=putdata(index,deleteway(args))
-      end
-    end
-
-    # ------------------
-    # Write out response
-
-    RAILS_DEFAULT_LOGGER.info("  Response: start")
-    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|
-      RAILS_DEFAULT_LOGGER.info("  Response: encode #{k}")
-      ans+=v
-    end
-    RAILS_DEFAULT_LOGGER.info("  Response: end")
-    render :text => ans
-
+	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
+	renumberedways={}							# Shared across repeated putways
+
+	# Parse request
+
+	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 '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 'findrelations';		results[index]=AMF.putdata(index,findrelations(*args))
+		when 'deleteway';			results[index]=AMF.putdata(index,deleteway(args[0],args[1].to_i))
+		when 'putpoi';				results[index]=AMF.putdata(index,putpoi(*args))
+		when 'getpoi';				results[index]=AMF.putdata(index,getpoi(*args))
+	  end
+	end
+
+	# Write out response
+
+	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
 
   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=''
-
-    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,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
-    return [presets,presetmenus,presetnames]
+  # Return presets (default tags, localisation etc.):
+  # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.
+
+  def getpresets() #:doc:
+	return POTLATCH_PRESETS
   end
 
-  # -----	whichways(left,bottom,right,top)
-  #		return array of ways in current bounding box
-  #		at present, instead of using correct (=more complex) SQL to find
-  #		corner-crossing ways, it simply enlarges the bounding box by +/- 0.01
-
-  def whichways(args)
-    xmin = args[0].to_f-0.01
-    ymin = args[1].to_f-0.01
-    xmax = args[2].to_f+0.01
-    ymax = args[3].to_f+0.01
-
-    RAILS_DEFAULT_LOGGER.info("  Message: whichways, bbox=#{xmin},#{ymin},#{xmax},#{ymax}")
-
-    waylist=WaySegment.find_by_sql("SELECT DISTINCT current_way_segments.id AS wayid"+
-       "  FROM current_way_segments,current_segments,current_nodes,current_ways "+
-       " WHERE segment_id=current_segments.id "+
-       "   AND current_segments.visible=1 "+
-       "   AND node_a=current_nodes.id "+
-	   "   AND current_ways.id=current_way_segments.id "+
-	   "   AND current_ways.visible=1 "+
-       "   AND (latitude  BETWEEN "+ymin.to_s+" AND "+ymax.to_s+") "+
-       "   AND (longitude BETWEEN "+xmin.to_s+" AND "+xmax.to_s+")")
-
-       ways = waylist.collect {|a| a.wayid.to_i } # get an array of way id's
-
-       pointlist =ActiveRecord::Base.connection.select_all("SELECT current_nodes.id,current_nodes.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 "+ymin.to_s+" AND "+ymax.to_s+") "+
-       "   AND (longitude BETWEEN "+xmin.to_s+" AND "+xmax.to_s+") "+
-       "   AND cs1.id IS NULL AND cs2.id IS NULL "+
-       "   AND current_nodes.visible=1")
-
-	    points = pointlist.collect {|a| [a['id'],tag2array(a['tags'])]	} # get a list of node ids and their tags
-
-    return [ways,points]
+  # 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. 
+
+  def whichways(xmin, ymin, xmax, ymax) #:doc:
+	xmin -= 0.01; ymin -= 0.01
+	xmax += 0.01; ymax += 0.01
+
+	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
+
+	  # 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] }
+
+	  # 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
+
+	[way_ids, points, relation_ids]
   end
 
-  # -----	getway (objectname, way, baselong, basey, masterscale)
-  #			returns objectname, array of co-ordinates, attributes,
-  #					xmin,xmax,ymin,ymax
-
-  def getway(args)
-    objname,wayid,baselong,basey,masterscale=args
-    wayid = wayid.to_i
-    points = []
-    lastid = -1
-    xmin = ymin = 999999
-    xmax = ymax = -999999
-
-    RAILS_DEFAULT_LOGGER.info("  Message: getway, id=#{wayid}")
-
-    readwayquery(wayid).each {|row|
-      xs1=long2coord(row['long1'].to_f,baselong,masterscale); ys1=lat2coord(row['lat1'].to_f,basey,masterscale)
-      xs2=long2coord(row['long2'].to_f,baselong,masterscale); ys2=lat2coord(row['lat2'].to_f,basey,masterscale)
-      points << [xs1,ys1,row['id1'].to_i,0,tag2array(row['tags1']),0] if (row['id1'].to_i!=lastid)
-      lastid = row['id2'].to_i
-      points << [xs2,ys2,row['id2'].to_i,1,tag2array(row['tags2']),row['segment_id'].to_i]
-      xmin = [xmin,row['long1'].to_f,row['long2'].to_f].min
-      xmax = [xmax,row['long1'].to_f,row['long2'].to_f].max
-      ymin = [ymin,row['lat1'].to_f,row['lat2'].to_f].min
-      ymax = [ymax,row['lat1'].to_f,row['lat2'].to_f].max
-    }
-
-    attributes={}
-    attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM current_way_tags WHERE id=#{wayid}"
-    attrlist.each {|a| attributes[a['k']]=a['v'] }
-
-    [objname,points,attributes,xmin,xmax,ymin,ymax]
+  # Find deleted ways in current bounding box (similar to whichways, but ways
+  # with a deleted node only - not POIs or relations).
+
+  def whichways_deleted(xmin, ymin, xmax, ymax) #:doc:
+	xmin -= 0.01; ymin -= 0.01
+	xmax += 0.01; ymax += 0.01
+
+	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
+
+	[way_ids]
   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)
-    return if !uid
-    db_uqs='uniq'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s	# temp uniquesegments table name, typically 51 chars
-    db_uqn='unin'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s	# temp uniquenodes table name, typically 51 chars
-    db_now='@now'+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s	# 'now' variable name, typically 51 chars
-    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
-    originalway=originalway.to_i
-
-    RAILS_DEFAULT_LOGGER.info("  Message: putway, id=#{way}")
-
-    # -- 3.	read original way into memory
-
-    xc={}; yc={}; tagc={}; seg={}
-    if originalway>0
-      way=originalway
-      readwayquery(way).each { |row|
-        id1=row['id1'].to_i; xc[id1]=row['long1'].to_f; yc[id1]=row['lat1'].to_f; tagc[id1]=row['tags1']
-        id2=row['id2'].to_i; xc[id2]=row['long2'].to_f; yc[id2]=row['lat2'].to_f; tagc[id2]=row['tags2']
-        seg[row['segment_id'].to_i]=id1.to_s+'-'+id2.to_s
-      }
-	  ActiveRecord::Base.connection.update("UPDATE current_ways SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id=#{way}")
-    else
-      way=ActiveRecord::Base.connection.insert("INSERT INTO current_ways (user_id,timestamp,visible) VALUES (#{uid},#{db_now},1)")
-    end
-
-    # -- 4.	get version by inserting new row into ways
-
-    version=ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},1)")
-
-    # -- 5. compare nodes and update xmin,xmax,ymin,ymax
-
-    xmin = ymin = 999999
-    xmax = ymax = -999999
-    insertsql = ''
-    renumberednodes={}
-
-    points.each_index do |i|
-      xs=coord2long(points[i][0],masterscale,baselong)
-      ys=coord2lat(points[i][1],masterscale,basey)
-      xmin=[xs,xmin].min; xmax=[xs,xmax].max
-      ymin=[ys,ymin].min; ymax=[ys,ymax].max
-      node=points[i][2].to_i
-      tagstr=array2tag(points[i][4])
-      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}")
-        end
-      else
-        # old node, created in another way and now added to this way
-      end
-
-    end
-
-
-    # -- 6.i compare segments
-
-    numberedsegments={}
-    seglist=''				# list of existing segments that we want to keep
-    for i in (0..(points.length-2))
-      if (points[i+1][3].to_i==0) then next end
-      segid=points[i+1][5].to_i
-      from =points[i  ][2].to_i
-      to   =points[i+1][2].to_i
-      if seg.has_key?(segid)
-        if 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}") }
-
-
-    # -- 6.ii insert new way segments
-
-    createuniquesegments(way,db_uqs,seglist)	# segments which appear in this way but no other
-
-    #		delete segments from uniquesegments (and not in modified way)
-
-    sql=<<-EOF
-      INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible) 
-      SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0
-        FROM current_segments AS cs, #{db_uqs} AS us
-       WHERE cs.id=us.segment_id AND cs.visible=1 
-    EOF
-    ActiveRecord::Base.connection.insert(sql)
-
-    sql=<<-EOF
-         UPDATE current_segments AS cs, #{db_uqs} AS us
-          SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid} 
-        WHERE cs.id=us.segment_id AND cs.visible=1 
-    EOF
-    ActiveRecord::Base.connection.update(sql)
-
-    #		delete nodes not in modified way or any other segments
-
-    createuniquenodes(db_uqs,db_uqn)	# nodes which appear in this way but no other
-
-    sql=<<-EOF
-		INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible)  
-		SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0 
-		  FROM current_nodes AS cn,#{db_uqn}
-		 WHERE cn.id=node_id
-    EOF
-    ActiveRecord::Base.connection.insert(sql)
-
-    sql=<<-EOF
-      UPDATE current_nodes AS cn, #{db_uqn}
-         SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
-       WHERE cn.id=node_id
-    EOF
-    ActiveRecord::Base.connection.update(sql)
-
-    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
-    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
-
-    #		insert new version of route into way_segments
-
-    insertsql =''
-    currentsql=''
-    sequence  =1
-    for i in (0..(points.length-2))
-      if (points[i+1][3].to_i==0) then next end
-      if insertsql !='' then insertsql +=',' end
-      if currentsql!='' then currentsql+=',' end
-      insertsql +="(#{way},#{points[i+1][5]},#{version})"
-      currentsql+="(#{way},#{points[i+1][5]},#{sequence})"
-      sequence  +=1
-    end
-
-    ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}");
-    ActiveRecord::Base.connection.insert("INSERT INTO         way_segments (id,segment_id,version    ) VALUES #{insertsql}");
-    ActiveRecord::Base.connection.insert("INSERT INTO current_way_segments (id,segment_id,sequence_id) VALUES #{currentsql}");
-
-    # -- 7. insert new way tags
-
-    insertsql =''
-    currentsql=''
-    attributes.each do |k,v|
-      if v=='' 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]
+  # 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
 
-  # -----	deleteway (user token, way)
-  #			returns way ID only
+  # 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.
+
+  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
+
+	old_way.tags['history'] = "Retrieved from v#{old_way.version}"
+
+	[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 deleteway(args)
-    usertoken,way=args
+  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
 
-    RAILS_DEFAULT_LOGGER.info("  Message: deleteway, id=#{way}")
+	['way',wayid,history]
+  end
 
-    uid=getuserid(usertoken); if !uid then return end
-	way=way.to_i
+  # Find history of a node. Returns 'node', id, and 
+  # an array of previous versions.
 
-	db_uqs='uniq'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s	# temp uniquesegments table name, typically 51 chars
-	db_uqn='unin'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s	# temp uniquenodes table name, typically 51 chars
-	db_now='@now'+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s	# 'now' variable name, typically 51 chars
-	ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
-	createuniquesegments(way,db_uqs,'')
+  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
 
-	# -	delete any otherwise unused segments
+	['node',nodeid,history]
+  end
 
-	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)
+  # 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)
 
-	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)
+	[relid, rel.tags, rel.members]
+  end
 
-	# - delete any unused nodes
+  # Find relations with specified name/id.
+  # Returns array of relations, each in same form as getrelation.
   
-    createuniquenodes(db_uqs,db_uqn)
+  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
 
-	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,#{db_uqn}
-		 WHERE cn.id=node_id
-    EOF
-	ActiveRecord::Base.connection.insert(sql)
+  # 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'
+		if mid < 0
+		  return -2, "Negative ID unresolved"
+		end
+	  end
+	  typedmembers << [m[0], mid, m[2]]
+	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
 
-	sql=<<-EOF
-      UPDATE current_nodes AS cn, #{db_uqn}
-         SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
-       WHERE cn.id=node_id
-    EOF
-	ActiveRecord::Base.connection.update(sql)
-	
-	ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
-	ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
+  # 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:
 
-	# - delete way
+	# -- Initialise and carry out checks
 	
-	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}")
+	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
+
+	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
+
+	# -- 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
+	  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
+
+	# -- Delete any unique nodes
 	
-	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 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
+	uniques.each do |n|
+	  deleteitemrelations(n, 'node')
 
-def createuniquesegments(way,uqs_name,seglist)
-  # Finds segments which appear in (previous version of) this way and no other
-  sql=<<-EOF
-      CREATE TEMPORARY TABLE #{uqs_name}
-              SELECT a.segment_id
-                FROM (SELECT DISTINCT segment_id FROM current_way_segments 
-                  WHERE id = #{way}) a
-             LEFT JOIN current_way_segments b 
-                ON b.segment_id = a.segment_id
-                 AND b.id != #{way}
-               WHERE b.segment_id IS NULL
-    EOF
-  if (seglist!='') then sql+=" AND a.segment_id NOT IN (#{seglist})" end
-  ActiveRecord::Base.connection.execute(sql)
-end
+	  node = Node.find(n)
+	  node.user_id = uid
+	  node.visible = false
+	  node.save_with_history!
+	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 OR 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
+	# -- Save revised way
 
-def sqlescape(a)
-  a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
-end
+	way.tags = attributes
+	way.nds = nodes
+	way.user_id = uid
+	way.visible = true
+	way.save_with_history!
 
-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('#%','=')
+	[0, originalway, way.id, renumberednodes]
   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('=','===')
+  # 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
+
+	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
-  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 email='#{$1}' AND pass_crypt=MD5('#{$2}')")
-  else
-    return ActiveRecord::Base.connection.select_value("SELECT id FROM users WHERE active=1 AND token='#{token}'")
+  # 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
+
+	if n
+	  return [n.id, n.lon, n.lat, n.tags_as_hash]
+	else
+	  return [nil, nil, nil, '']
+	end
   end
-end
-
 
+  # Delete way and all constituent nodes. Also removes from any relations.
+  # Returns 0 (success), unchanged way id.
 
-# ====================================================================
-# AMF read subroutines
+  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
 
-# -----	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
+	# 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 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
+	way.delete_with_relations_and_nodes_and_history(user)  
 
-def getdouble(s)
-  a=s.read(8).unpack('G')			# G big-endian, E little-endian
-  a[0]
-end
-
-def getarray(s)
-  len=getlong(s)
-  arr=[]
-  for i in (0..len-1)
-    arr[i]=getvalue(s)
-  end
-  arr
-end
-
-def getobject(s)
-  arr={}
-  while (key=getstring(s))
-    if (key=='') then break end
-    arr[key]=getvalue(s)
+	[0, way_id]
   end
-  s.getc		# skip the 9 'end of object' value
-  arr
-end
 
-# -----	getvalue	parse and get value
-
-def getvalue(s)
-  case s.getc
-  when 0;	return getdouble(s)			# number
-  when 1;	return s.getc				# boolean
-  when 2;	return getstring(s)			# string
-  when 3;	return getobject(s)			# object/hash
-  when 5;	return nil					# null
-  when 6;	return nil					# undefined
-  when 8;	s.read(4)					# mixedArray
-    return getobject(s)			#  |
-  when 10;return getarray(s)			# array
-  else;	return nil					# error
-  end
-end
 
-# ====================================================================
-# AMF write subroutines
+  # ====================================================================
+  # Support functions
 
-# -----	putdata		envelope data into AMF writeable form
-# -----	encodevalue	pack variables as AMF
+  # Remove a node or way from all relations
 
-def putdata(index,n)
-  d =encodestring(index+"/onResult")
-  d+=encodestring("null")
-  d+=[-1].pack("N")
-  d+=encodevalue(n)
-end
+  def deleteitemrelations(objid, type) #:doc:
+	relations = RelationMember.find(:all, 
+									:conditions => ['member_type = ? and member_id = ?', type, objid], 
+									:include => :relation).collect { |rm| rm.relation }.uniq
 
-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)
+	relations.each do |rel|
+	  rel.members.delete_if { |x| x[0] == type and x[1] == objid }
+	  rel.save_with_history!
+	end
   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
+  # Break out node tags into a hash
+  # (should become obsolete as of API 0.6)
 
-def encodestring(n)
-  a,b=n.size.divmod(256)
-  a.chr+b.chr+n
-end
+  def tagstring_to_hash(a) #:doc:
+	tags={}
+	Tags.split(a) do |k, v|
+	  tags[k]=v
+	end
+	tags
+  end
 
-def encodedouble(n)
-  [n].pack('G')
-end
+  # Authenticate token
+  # (could be removed if no-one uses the username+password form)
 
-def encodelong(n)
-  [n].pack('N')
-end
+  def getuserid(token) #:doc:
+	if (token =~ /^(.+)\+(.+)$/) then
+	  user = User.authenticate(:username => $1, :password => $2)
+	else
+	  user = User.authenticate(:token => token)
+	end
 
-# ====================================================================
-# Co-ordinate conversion
+	return user ? user.id : nil;
+  end
 
-def lat2coord(a,basey,masterscale)
-  -(lat2y(a)-basey)*masterscale+250
-end
+  # Compare two floating-point numbers to within 0.0000001
 
-def long2coord(a,baselong,masterscale)
-  (a-baselong)*masterscale+350
-end
+  def fpcomp(a,b) #:doc:
+	return ((a/0.0000001).round==(b/0.0000001).round)
+  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
+  # ====================================================================
+  # Alternative SQL queries for getway/whichways
 
-def coord2long(a,masterscale,baselong)
-  (a-350)/masterscale+baselong
-end
+  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 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 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 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 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
 
-def y2lat(a)
-  180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
 end
 
-end
+# Local Variables:
+# indent-tabs-mode: t
+# tab-width: 4
+# End: