-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
--
-- PostGIS - Spatial Types for PostgreSQL
-- http://postgis.net
--
-- Copyright (C) 2010-2015 Sandro Santilli <strk@kbt.io>
-- Copyright (C) 2005 Refractions Research Inc.
--
-- This is free software; you can redistribute and/or modify it under
-- the terms of the GNU General Public Licence. See the COPYING file.
--
-- Author: Sandro Santilli <strk@kbt.io>
--
--

/* #define POSTGIS_TOPOLOGY_DEBUG 1 */

--={ ----------------------------------------------------------------
--  SQL/MM block
--
--  This part contains function in the SQL/MM specification
--
---------------------------------------------------------------------

--
-- Type returned by ST_GetFaceEdges
--
CREATE TYPE topology.GetFaceEdges_ReturnType AS (
  sequence integer,
  edge integer
);

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.5
--
--  ST_GetFaceEdges(atopology, aface)
--
--
--
CREATE OR REPLACE FUNCTION topology.ST_GetFaceEdges(toponame varchar, face_id integer)
  RETURNS SETOF topology.GetFaceEdges_ReturnType AS
	'MODULE_PATHNAME', 'ST_GetFaceEdges'
  LANGUAGE 'c' STABLE;
--} ST_GetFaceEdges

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.10
--
--  ST_NewEdgeHeal(atopology, anedge, anotheredge)
--
-- Not in the specs:
-- * Refuses to heal two edges if any of the two is closed
-- * Raise an exception when trying to heal an edge with itself
-- * Raise an exception if any TopoGeometry is defined by only one
--   of the two edges
-- * Update references in the Relation table.
--
CREATE OR REPLACE FUNCTION topology.ST_NewEdgeHeal(toponame varchar, e1id integer, e2id integer)
  RETURNS int AS
  'MODULE_PATHNAME','ST_NewEdgeHeal'
  LANGUAGE 'c' VOLATILE;
--} ST_NewEdgeHeal

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.11
--
--  ST_ModEdgeHeal(atopology, anedge, anotheredge)
--
-- Not in the specs:
-- * Returns the id of the node being removed
-- * Refuses to heal two edges if any of the two is closed
-- * Raise an exception when trying to heal an edge with itself
-- * Raise an exception if any TopoGeometry is defined by only one
--   of the two edges
-- * Update references in the Relation table.
-- {
CREATE OR REPLACE FUNCTION topology.ST_ModEdgeHeal(toponame varchar, e1id integer, e2id integer)
  RETURNS int AS
  'MODULE_PATHNAME','ST_ModEdgeHeal'
  LANGUAGE 'c' VOLATILE;
--} ST_ModEdgeHeal

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.14
--
--  ST_RemEdgeNewFace(atopology, anedge)
--
-- Not in the specs:
-- * Raise an exception if any TopoGeometry is defined by only one
--   of the two faces that will dissolve.
-- * Raise an exception if any TopoGeometry is defined by
--   the edge being removed.
-- * Properly set containg_face on nodes that remains isolated by the drop
-- * Update containg_face for isolated nodes in the dissolved faces
-- * Update references in the Relation table
--
-- }{
CREATE OR REPLACE FUNCTION topology.ST_RemEdgeNewFace(toponame varchar, e1id integer)
  RETURNS int AS
	'MODULE_PATHNAME','ST_RemEdgeNewFace'
  LANGUAGE 'c' VOLATILE;
--} ST_RemEdgeNewFace

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.15
--
--  ST_RemEdgeModFace(atopology, anedge)
--
-- Not in the specs:
-- * Raise an exception if any TopoGeometry is defined by only one
--   of the two faces that will dissolve.
-- * Raise an exception if any TopoGeometry is defined by
--   the edge being removed.
-- * Properly set containg_face on nodes that remains isolated by the drop
-- * Update containg_face for isolated nodes in the dissolved faces
-- * Update references in the Relation table
-- * Return id of the face taking up the removed edge space
--
-- }{
CREATE OR REPLACE FUNCTION topology.ST_RemEdgeModFace(toponame varchar, e1id integer)
  RETURNS int AS
	'MODULE_PATHNAME','ST_RemEdgeModFace'
  LANGUAGE 'c' VOLATILE;
--} ST_RemEdgeModFace

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.16
--
--  ST_GetFaceGeometry(atopology, aface)
--
CREATE OR REPLACE FUNCTION topology.ST_GetFaceGeometry(toponame varchar, aface integer)
  RETURNS GEOMETRY AS
	'MODULE_PATHNAME', 'ST_GetFaceGeometry'
  LANGUAGE 'c' STABLE;
--} ST_GetFaceGeometry

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.1
--
--  ST_AddIsoNode(atopology, aface, apoint)
--
CREATE OR REPLACE FUNCTION topology.ST_AddIsoNode(atopology varchar, aface integer, apoint geometry)
  RETURNS INTEGER AS
	'MODULE_PATHNAME','ST_AddIsoNode'
  LANGUAGE 'c' VOLATILE;
--} ST_AddIsoNode

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.2
--
--  ST_MoveIsoNode(atopology, anode, apoint)
--
CREATE OR REPLACE FUNCTION topology.ST_MoveIsoNode(atopology character varying, anode integer, apoint geometry)
  RETURNS text AS
  'MODULE_PATHNAME','ST_MoveIsoNode'
  LANGUAGE 'c' VOLATILE;
--} ST_MoveIsoNode

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.3
--
--  ST_RemoveIsoNode(atopology, anode)
--
CREATE OR REPLACE FUNCTION topology.ST_RemoveIsoNode(atopology varchar, anode integer)
  RETURNS TEXT AS
	'MODULE_PATHNAME','ST_RemoveIsoNode'
  LANGUAGE 'c' VOLATILE;
--} ST_RemoveIsoNode

--{
-- According to http://trac.osgeo.org/postgis/ticket/798
-- ST_RemoveIsoNode was renamed to ST_RemIsoNode in the final ISO
-- document
--
CREATE OR REPLACE FUNCTION topology.ST_RemIsoNode(varchar, integer)
  RETURNS TEXT AS
	'MODULE_PATHNAME','ST_RemoveIsoNode'
  LANGUAGE 'c' VOLATILE;
--} ST_RemIsoNode

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.7
--
--  ST_RemoveIsoEdge(atopology, anedge)
--
CREATE OR REPLACE FUNCTION topology.ST_RemoveIsoEdge(atopology varchar, anedge integer)
  RETURNS TEXT AS
	'MODULE_PATHNAME','ST_RemIsoEdge'
	LANGUAGE 'c' VOLATILE;
--} ST_RemoveIsoEdge

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.8
--
--  ST_NewEdgesSplit(atopology, anedge, apoint)
--
-- Not in the specs:
-- * Update references in the Relation table.
--
CREATE OR REPLACE FUNCTION topology.ST_NewEdgesSplit(atopology varchar, anedge integer, apoint geometry)
  RETURNS INTEGER AS
  'MODULE_PATHNAME','ST_NewEdgesSplit'
  LANGUAGE 'c' VOLATILE;
--} ST_NewEdgesSplit

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.9
--
--  ST_ModEdgeSplit(atopology, anedge, apoint)
--
-- Not in the specs:
-- * Update references in the Relation table.
--
CREATE OR REPLACE FUNCTION topology.ST_ModEdgeSplit(atopology varchar, anedge integer, apoint geometry)
  RETURNS INTEGER AS
	'MODULE_PATHNAME','ST_ModEdgeSplit'
  LANGUAGE 'c' VOLATILE;
--} ST_ModEdgesSplit

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.4
--
--  ST_AddIsoEdge(atopology, anode, anothernode, acurve)
--
-- Not in the specs:
-- * Reset containing_face for starting and ending point,
--   as they stop being isolated nodes
-- * Refuse to add a closed edge, as it would not be isolated
--   (ie: would create a ring)
--
-- }{
--
CREATE OR REPLACE FUNCTION topology.ST_AddIsoEdge(atopology varchar, anode integer, anothernode integer, acurve geometry)
  RETURNS INTEGER AS
	'MODULE_PATHNAME','ST_AddIsoEdge'
  LANGUAGE 'c' VOLATILE;
--} ST_AddIsoEdge

-- Internal function used by ST_ChangeEdgeGeom to compare
-- adjacent edges of an edge endpoint
--
-- @param anode the node to use edge end star of
-- @param anedge the directed edge to get adjacents from
--        if positive `anode' is assumed to be its start node
--        if negative `anode' is assumed to be its end node
--
-- @todo DROP, NOT NEEDED ANYMORE (might need to go in some _drop, I guess)
-- {
CREATE OR REPLACE FUNCTION topology._ST_AdjacentEdges(atopology varchar, anode integer, anedge integer)
RETURNS integer[] AS
$$
DECLARE
  ret integer[];
BEGIN
  WITH edgestar AS (
    SELECT *, count(*) over () AS cnt
    FROM topology.GetNodeEdges(atopology, anode)
  )
  SELECT ARRAY[ (
      SELECT p.edge AS prev FROM edgestar p
      WHERE p.sequence = CASE WHEN m.sequence-1 < 1 THEN cnt
                         ELSE m.sequence-1 END
    ), (
      SELECT p.edge AS prev FROM edgestar p WHERE p.sequence = ((m.sequence)%cnt)+1
    ) ]
  FROM edgestar m
  WHERE edge = anedge
  INTO ret;

  RETURN ret;
END
$$
LANGUAGE 'plpgsql' STABLE;
--}

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.6
--
--  ST_ChangeEdgeGeom(atopology, anedge, acurve)
--
-- Not in the specs:
-- * Raise an exception if given a non-existent edge
-- * Raise an exception if movement is not topologically isomorphic
--
-- }{
CREATE OR REPLACE FUNCTION topology.ST_ChangeEdgeGeom(atopology varchar, anedge integer, acurve geometry)
  RETURNS TEXT AS
	'MODULE_PATHNAME','ST_ChangeEdgeGeom'
  LANGUAGE 'c' VOLATILE;
--} ST_ChangeEdgeGeom

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.12
--
--  ST_AddEdgeNewFaces(atopology, anode, anothernode, acurve)
--
-- Not in the specs:
-- * Reset containing_face for starting and ending point,
--   as they stop being isolated nodes
-- * Update references in the Relation table.
--
CREATE OR REPLACE FUNCTION topology.ST_AddEdgeNewFaces(atopology varchar, anode integer, anothernode integer, acurve geometry)
  RETURNS INTEGER AS
	'MODULE_PATHNAME','ST_AddEdgeNewFaces'
  LANGUAGE 'c' VOLATILE;
--} ST_AddEdgeNewFaces

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.13
--
--  ST_AddEdgeModFace(atopology, anode, anothernode, acurve)
--
-- Not in the specs:
-- * Reset containing_face for starting and ending point,
--   as they stop being isolated nodes
-- * Update references in the Relation table.
--
CREATE OR REPLACE FUNCTION topology.ST_AddEdgeModFace(atopology varchar, anode integer, anothernode integer, acurve geometry)
  RETURNS INTEGER AS
	'MODULE_PATHNAME','ST_AddEdgeModFace'
  LANGUAGE 'c' VOLATILE;
--} ST_AddEdgeModFace

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.17
--
--  ST_InitTopoGeo(atopology)
--
CREATE OR REPLACE FUNCTION topology.ST_InitTopoGeo(atopology varchar)
RETURNS text
AS
$$
DECLARE
  rec RECORD;
  topology_id numeric;
BEGIN
  IF atopology IS NULL THEN
    RAISE EXCEPTION 'SQL/MM Spatial exception - null argument';
  END IF;

  FOR rec IN SELECT * FROM pg_namespace WHERE text(nspname) = atopology
  LOOP
    RAISE EXCEPTION 'SQL/MM Spatial exception - schema already exists';
  END LOOP;

  FOR rec IN EXECUTE 'SELECT topology.CreateTopology('
    ||quote_literal(atopology)|| ') as id'
  LOOP
    topology_id := rec.id;
  END LOOP;

  RETURN 'Topology-Geometry ' || quote_literal(atopology)
    || ' (id:' || topology_id || ') created.';
END
$$
LANGUAGE 'plpgsql' VOLATILE;
--} ST_InitTopoGeo

--{
-- Topo-Geo and Topo-Net 3: Routine Details
-- X.3.18
--
--  ST_CreateTopoGeo(atopology, acollection)
--}{
CREATE OR REPLACE FUNCTION topology.ST_CreateTopoGeo(atopology varchar, acollection geometry)
RETURNS text
AS
$$
DECLARE
  typ char(4);
  rec RECORD;
  ret int;
  nodededges GEOMETRY;
  points GEOMETRY;
  snode_id int;
  enode_id int;
  tolerance FLOAT8;
  topoinfo RECORD;
BEGIN

  IF atopology IS NULL OR acollection IS NULL THEN
    RAISE EXCEPTION 'SQL/MM Spatial exception - null argument';
  END IF;

  -- Get topology information
  BEGIN
    SELECT * FROM topology.topology
      INTO STRICT topoinfo WHERE name = atopology;
  EXCEPTION
    WHEN NO_DATA_FOUND THEN
      RAISE EXCEPTION 'SQL/MM Spatial exception - invalid topology name';
  END;

  -- Check SRID compatibility
  IF ST_SRID(acollection) != topoinfo.SRID THEN
    RAISE EXCEPTION 'Geometry SRID (%) does not match topology SRID (%)',
      ST_SRID(acollection), topoinfo.SRID;
  END IF;

  -- Verify pre-conditions (valid, empty topology schema exists)
  BEGIN -- {

    -- Verify the topology views in the topology schema to be empty
    FOR rec in EXECUTE
      'SELECT count(*) FROM '
      || quote_ident(atopology) || '.edge_data '
      || ' UNION ' ||
      'SELECT count(*) FROM '
      || quote_ident(atopology) || '.node '
    LOOP
      IF rec.count > 0 THEN
    RAISE EXCEPTION 'SQL/MM Spatial exception - non-empty view';
      END IF;
    END LOOP;

    -- face check is separated as it will contain a single (world)
    -- face record
    FOR rec in EXECUTE
      'SELECT count(*) FROM '
      || quote_ident(atopology) || '.face '
    LOOP
      IF rec.count != 1 THEN
    RAISE EXCEPTION 'SQL/MM Spatial exception - non-empty face view';
      END IF;
    END LOOP;

  EXCEPTION
    WHEN INVALID_SCHEMA_NAME THEN
      RAISE EXCEPTION 'SQL/MM Spatial exception - invalid topology name';
    WHEN UNDEFINED_TABLE THEN
      RAISE EXCEPTION 'SQL/MM Spatial exception - non-existent view';

  END; -- }

#ifdef POSTGIS_TOPOLOGY_DEBUG
  RAISE DEBUG 'Noding input linework';
#endif

  --
  -- Node input linework with itself
  --
  WITH components AS ( SELECT geom FROM ST_Dump(acollection) )
  SELECT ST_UnaryUnion(ST_Collect(geom)) FROM (
    SELECT geom FROM components
      WHERE ST_Dimension(geom) = 1
    UNION ALL
    SELECT ST_Boundary(geom) FROM components
      WHERE ST_Dimension(geom) = 2
  ) as linework INTO STRICT nodededges;

#ifdef POSTGIS_TOPOLOGY_DEBUG
  RAISE DEBUG 'Computed % noded edges', ST_NumGeometries(nodededges);
#endif

  --
  -- Linemerge the resulting edges, to reduce the working set
  -- NOTE: this is more of a workaround for GEOS splitting overlapping
  --       lines to each of the segments.
  --
  SELECT ST_LineMerge(nodededges) INTO STRICT nodededges;

#ifdef POSTGIS_TOPOLOGY_DEBUG
  RAISE DEBUG 'Merged edges: %', ST_NumGeometries(nodededges);
#endif

  --
  -- Collect input points and input lines endpoints
  --
  WITH components AS ( SELECT geom FROM ST_Dump(acollection) )
  SELECT ST_Union(geom) FROM (
    SELECT geom FROM components
      WHERE ST_Dimension(geom) = 0
    UNION ALL
    SELECT ST_Boundary(geom) FROM components
      WHERE ST_Dimension(geom) = 1
  ) as nodes INTO STRICT points;

#ifdef POSTGIS_TOPOLOGY_DEBUG
  RAISE DEBUG 'Collected % input points', ST_NumGeometries(points);
#endif

  --
  -- Further split edges by points
  -- TODO: optimize this adding ST_Split support for multiline/multipoint
  --
  FOR rec IN SELECT geom FROM ST_Dump(points)
  LOOP
    -- Use the node to split edges
    SELECT ST_Collect(geom)
    FROM ST_Dump(ST_Split(nodededges, rec.geom))
    INTO STRICT nodededges;
  END LOOP;
  SELECT ST_UnaryUnion(nodededges) INTO STRICT nodededges;

#ifdef POSTGIS_TOPOLOGY_DEBUG
  RAISE DEBUG 'Noded edges became % after point-split',
    ST_NumGeometries(nodededges);
#endif

  --
  -- Collect all nodes (from points and noded linework endpoints)
  --

  WITH edges AS ( SELECT geom FROM ST_Dump(nodededges) )
  SELECT ST_Union( -- TODO: ST_UnaryUnion ?
          COALESCE(ST_UnaryUnion(ST_Collect(geom)),
            ST_SetSRID('POINT EMPTY'::geometry, topoinfo.SRID)),
          COALESCE(points,
            ST_SetSRID('POINT EMPTY'::geometry, topoinfo.SRID))
         )
  FROM (
    SELECT ST_StartPoint(geom) as geom FROM edges
      UNION ALL
    SELECT ST_EndPoint(geom) FROM edges
  ) as endpoints INTO points;

#ifdef POSTGIS_TOPOLOGY_DEBUG
  RAISE DEBUG 'Total nodes count: %', ST_NumGeometries(points);
#endif

  --
  -- Add all nodes as isolated so that
  -- later calls to AddEdgeModFace will tweak their being
  -- isolated or not...
  --
  FOR rec IN SELECT geom FROM ST_Dump(points)
  LOOP
    PERFORM topology.ST_AddIsoNode(atopology, 0, rec.geom);
  END LOOP;

  FOR rec IN SELECT geom FROM ST_Dump(nodededges)
  LOOP
    SELECT topology.GetNodeByPoint(atopology, st_startpoint(rec.geom), 0)
      INTO STRICT snode_id;
    SELECT topology.GetNodeByPoint(atopology, st_endpoint(rec.geom), 0)
      INTO STRICT enode_id;
    PERFORM topology.ST_AddEdgeModFace(atopology, snode_id, enode_id, rec.geom);
  END LOOP;

  RETURN 'Topology ' || atopology || ' populated';

END
$$
LANGUAGE 'plpgsql' VOLATILE;
--} ST_CreateTopoGeo

--=}  SQL/MM block

