################################################################################
### Optimizes networks from imported OSM data (optional)
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### Description:
### - This script optimizes networks from imported OSM data.
### Please, see tu_osm_import.sh for further details. 
###
### Preconditions:
###
### Postconditions:
###
### Author:
### - Thomas Uchdorf, thomas.uchdorf(at)fernuni-hagen.de
################################################################################

# Finding junctions between unidirectional streets
#             A   a   B
# StartNode_a x------>x End_Node_a
#             |       |
#           b |       | d
#             |       |
# EndNode_b   x<------x Start_Node_b
#             D   c  C
# Parallelogram law
# sum of the squares of the length of the sides = sum of the squares of the
# length of the diagonals
# a^2 + b^2 + c^2 + d^2 = diag1^2 +diag2^2
# <=> 2 a^2 + 2 b^2 - diag1^2 - diag2^2 = 0
# here we are looking for something close to a parallelogram, so we have
# 2 a^2 + 2 b^2 - diag1^2 - diag2^2 < epsilon 
query 
   (((ExtSectionsRel feed
      project [StreetId,StartNodeId,EndNodeId,Section] {a}
      NodesRel feed {n1}
      hashjoin [StartNodeId_a,NodeId_n1,99997])
     NodesRel feed {n2}
     hashjoin [EndNodeId_a,NodeId_n2,99997])
    extend [StartNode_a: .Node_n1, EndNode_a: .Node_n2]
    ExtStreetsRel feed
    filter [.OneWay = 1]
    project [GroupId,StreetId,GeoData,Name] {e1}
    hashjoin [StreetId_a,StreetId_e1,99997])
   (((ExtSectionsRel feed
      project [StreetId,StartNodeId,EndNodeId,Section] {b} 
      NodesRel feed {n3}
      hashjoin [StartNodeId_b,NodeId_n3,99997])
     nodesRel feed {n4}
     hashjoin [EndNodeId_b,NodeId_n4,99997])
    extend [StartNode_b: .Node_n3, EndNode_b: .Node_n4]
    ExtStreetsRel feed
    filter [.OneWay = 1]
    project [GroupId,StreetId,GeoData] {e2}
    hashjoin [StreetId_b,StreetId_e2,99997])
   hashjoin [GroupId_e1,GroupId_e2,99997]
   filter [.StreetId_e1 < .StreetId_e2]
   projectextend [
      StreetId_a,Name_e1,GroupId_e1,
      Section_a,Section_b,GeoData_e1,GeoData_e2;
      A: distance(.StartNode_a,.EndNode_a),
      B: distance(.StartNode_a,.EndNode_b),
      C: distance(.EndNode_b,.StartNode_b),
      D: distance(.EndNode_a,.StartNode_b),
      Diag1: distance(.StartNode_a,.StartNode_b),
      Diag2: distance(.EndNode_a,.EndNode_b)]
   sortby [GroupId_e1]
   filter [(abs(.A - .C) < (0.1 * getMaxVal(.A,.C)))
      and (abs(.B - .D) < (0.1 * getMaxVal(.B,.D)))
      and (abs(2 * ((.A * .A) + (.B * .B)) -
         (.Diag1 * .Diag1) - (.Diag2 * .Diag2)) < 0.0001)]
   consume;

#query 
#extStreetsRel feed {a}
#extend [StartNode_a: atposition(.geoData_a,0.0,TRUE),
#   EndNode_a: atposition(.geoData_a,1.0,TRUE)]
#filter [.oneWay_a = 1] 
#extStreetsRel feed {b} 
#extend [StartNode_b: atposition(.geoData_b,0.0,TRUE),
#   EndNode_b: atposition(.geoData_b,1.0,TRUE)]
#filter [.oneWay_b = 1] 
#hashjoin [groupId_a,groupId_b,99997] 
#filter [.streetId_a < .streetId_b]
#extend [a: distance(.StartNode_a,.EndNode_a),
#        aSharp: distance(.EndNode_b,.StartNode_b),
#        b: distance(.StartNode_a,.EndNode_b),
#        bSharp: distance(.EndNode_a,.StartNode_b),
#        diag1: distance(.StartNode_a,.StartNode_b),
#        diag2: distance(.EndNode_a,.EndNode_b)]
#sortby [groupId_a] 
#filter [(abs(.a - .aSharp) < (0.1 * getMaxVal(.a,.aSharp))) 
#   and (abs(.b - .bSharp) < (0.1 * getMaxVal(.b,.bSharp)))
#   and (abs(2 * ((.a * .a) + (.b * .b)) - (.diag1 * .diag1) - (.diag2 * .diag2)) < 0.0001)]
#consume;