#  Particles are distributed at the nodes of a grid formed by equilateral
#  triangles. The distance between the particles, ie the length of the sides of
#  the triangles,is determined by the requirement that the area one particle
#  represents times the number of particles should equal the area of the polygon
#  determined by the outlet vertices. The "area" of one particle corresponds to
#  twice the area of one equilateral triangle, which equals
#  sqrt(3)/4*ParticleDistance**2.

#  A grid of equilateral triangles forms regular hexagons. The algorithm to
#  distribute particles is to determine one starting point, then move around
#  this following the sides of increasingly larger regular hexagons. The first
#  hexagon around the starting point has 6 vertices, the next has 12, the next
#  has 18, and so on.

#  The number of nodes are
#  1+6*1+6*2+6*3+...+6*n = 1+6*(1+2+3...+n) = 1+6*(n/2*(n+1))
#  where n is the number of hexagons (n is also the number of ParticleDistances
#  from  the center to a node on the outermost hexagon)
import math
import json
import random
import time
from output import Output
from output import Particletrack
from output import Cloudtrack
from shapely import geometry
from shapely.geometry import LineString
from shapely.strtree import STRtree
from shapely.geometry import MultiLineString



class Model(object):
  def __init__(self):
    return
  def __call__(self):  
    return self

  def centerPoints(self, newLatLng, centroid, points):
    centered = []
    center = [centroid.x,centroid.y]
    for point in points: 
      latlng = [point.x, point.y]
      centered.append(self.centerPoint(newLatLng, center, latlng))    
    return centered
    
  def centerPoint(self, newCenter, oldCenter, latlng):
    if (latlng[0] > oldCenter[0]):
      lat = abs(latlng[0] - oldCenter[0]) + newCenter[0]
    else: 
      lat = newCenter[0] - abs(latlng[0] - oldCenter[0])
    
    if (latlng[1] > oldCenter[1]):
      lng = abs(latlng[1] - oldCenter[1]) + newCenter[1]
    else: 
      lng = newCenter[1] - abs(latlng[1] - oldCenter[1])
    
    return [lat, lng]        

  def createHexagon(self, size, center, lvl):
    sizeLvl = size * lvl
    coords = []
    nodes = []
    for i in range(6):
      angle = 2 * math.pi / 6 * (i + 0.5)
      lat_i = center.x + sizeLvl * math.cos(angle)
      lng_i = center.y + sizeLvl * math.sin(angle) * 1.5
      coords.append(geometry.Point(lat_i, lng_i))

    for i, coord in enumerate(coords):
      nodes.append(coord)
      if lvl > 1:
        index = 0
        if (i + 1) < len(coords):
          index = i + 1
      
        latDiff = (coords[index].x - coord.x) / lvl
        lngDiff = (coords[index].y - coord.y) / lvl
        j = 1
        while (j < lvl):
          nodes.append(geometry.Point(coord.x + (latDiff * j), coord.y + (lngDiff * j)))
          j += 1
    if (lvl == 1):
      nodes.append(center)
    return {
        'center': center,
        'coordinates': coords,
        'nodes': nodes
    }
    


  def createOutlet(self,geom):
    nrOfParticles = 300
    center = geom.centroid
    points = []
    depth = []
    properties = {}
    properties['depth'] = depth
    if (geom.geom_type == 'Point'):
      geom = geom.buffer(0.001)
    if (geom.geom_type == 'LineString'):
      geom = geom.buffer(0.01, 20)
    pArea = (geom.area)/3
    pDist = math.sqrt((4*pArea)/(nrOfParticles*math.sqrt(3)))
    counter = 0
    lvl = 1
    while (counter < nrOfParticles):
      hexagon = self.createHexagon(pDist, center, lvl)
      nodes = hexagon['nodes']
      j = 0
      while (j < len(nodes)):
        point = nodes[j]
        if geom.contains(point):
          points.append(point)
          depth.append(0.0)
          counter += 1
        if (counter == nrOfParticles):
          break
        j += 1
      lvl += 1
      if (lvl > 100):
        break

    print("Outlet particles count: "+str(counter))

    return geometry.MultiPoint(points),pDist

  def createFeatureCollection(self):
    featurecollection = {}
    featurecollection["type"] = "FeatureCollection"
    featurecollection["features"] = []
    return featurecollection
    
  def createFeature(self, geom, properties = {}):
    featurecollection = {}
    featurecollection["type"] = "Feature"
    featurecollection["properties"] = properties
    featurecollection["geometry"] = geometry.mapping(geom)
    return featurecollection


  def onlandPoints(self, beforepoints, nowpoints, matches):
    active = []
    deactive = []
    for i in range(len(beforepoints)):
      queryline = LineString([[beforepoints[i].y,beforepoints[i].x],[nowpoints[i][1],nowpoints[i][0]]])
      intersection = None
      if (len(matches) > 0):
        for match in matches:
          if match.intersects(queryline):
            intersection = match.intersection(queryline)
      if (intersection is not None):
        deactive.append([intersection.coords[0][0],intersection.coords[0][1]])
      else:
        active.append(nowpoints[i])

    intersectionend = time.time()

    return active, deactive

  def onlandPoints2(self, beforepoints, nowpoints, matches):
    active = []
    deactive = []
    multilines = []

    intersectionstart = time.time()

    for i in range(len(beforepoints)):
      multilines.append(LineString([[beforepoints[i].y,beforepoints[i].x],[nowpoints[i][1],nowpoints[i][0]]]))

    intercepts = [match.intersection(MultiLineString(multilines)) for match in matches]


    # if (len(matches) == 3):
    #   print(len(matches[2].coords))       
    #   print(matches[2].intersection(query))

    # intercepts = [match.intersection(query) for match in matches]
    # if (len(intercepts)):
    #   print(intercepts)
    # for i in range(len(multilines)):
    #   intercepts = [multilines[i] for match in matches if match.intersects(multilines[i])]
    # if (len(intercepts)):
    #   print(intercepts)
    active = list(nowpoints)
    # if (len(matches) > 0):
    #   print(len(matches))
    # for i in range(len(multilines)):
    #   intersection = None
    #   for match in matches:
    #     intersection = match.intersection(multilines[i])
    #     if (not intersection.is_empty):
    #       break
    #     # if match.intersects(multilines[i]):
    #   print(intersection)
    #   if (intersection.is_empty):
    #     active.append(nowpoints[i])
    #   else:
    #     deactive.append([intersection.y,intersection.x])
    intersectionend = time.time()
    print('intersection: '+str(intersectionend-intersectionstart))

    return active, deactive

  def calculateRadius(self, pDist, points):
    radius = [pDist] * len(points)

    for i in range(len(points)):
      radius[i] *= random.uniform(0.05, 3)

    return radius



  def displacePoints(self, pDist, points):
      
    p = 0
    xdisp = [0] * len(points)
    ydisp = [0] * len(points)
    minoverlap = [float('Inf')] * len(points)
    radius = self.calculateRadius(pDist, points)
    while (p < len(points)):
      pn = 0
      while (pn < len(points)):
        dx = points[p][0] - points[pn][0]
        dy = points[p][1] - points[pn][1]
        centerdist = math.sqrt(dx*dx + dy*dy)
        overlap = radius[p] + radius[pn] - centerdist
        if overlap > 0:
          minoverlap[p]  = min(minoverlap[p], overlap)
          minoverlap[pn] = min(minoverlap[pn], overlap)
          if centerdist > 0:
            cosalfa = (points[pn][0] - points[p][0]) / centerdist
            sinalfa = (points[pn][1] - points[p][1]) / centerdist
          else:
            rand = random.uniform(0, 1)
            cosalfa = math.cos(rand * math.pi*math.pi)
            sinalfa = math.sin(rand * math.pi*math.pi)
          xdisp[p] = xdisp[p] - 0.5 * cosalfa * overlap
          ydisp[p] = ydisp[p] - 0.5 * sinalfa * overlap
          xdisp[pn] = xdisp[pn] + 0.5 * cosalfa * overlap
          ydisp[pn] = ydisp[pn] + 0.5 * sinalfa * overlap
        pn += 1

      disp = math.sqrt(xdisp[p]*xdisp[p]+ydisp[p]*ydisp[p])

      maxdisp = min(radius[p], 0.5 * minoverlap[p])
      if (disp > maxdisp):
        xdisp[p] = xdisp[p] * maxdisp / disp
        ydisp[p] = ydisp[p] * maxdisp / disp
      p += 1
    


    result = list(points)
    for i, dx in enumerate(xdisp):
      result[i][0] += dx 
    for i, dy in enumerate(ydisp):
      result[i][1] += dy 

    return result


  def createProperties(self, step, time, centroid, level, category):
    properties = {};
    properties['nStep'] = step
    properties['time'] = time
    properties['meanLat'] = centroid.y
    properties['meanLon'] = centroid.x
    properties['category'] = category
    properties['level'] = level
    return properties    


  def createOutput(self, starttime, pDist, multipoint, exercisefeature, strtree):

    featurecollection = self.createFeatureCollection()
    features = featurecollection['features']
    timearray = exercisefeature['properties']['time']
    properties = self.createProperties(1, starttime, multipoint.centroid, [0] * len(multipoint.geoms), [2] * len(multipoint.geoms))
    features.append(self.createFeature(multipoint, properties))
    mp = multipoint
    activepoints = []
    deactivepoints = []
    linestring = geometry.shape(exercisefeature['geometry'])
    latlngpoints = [[latlng[1], latlng[0]] for latlng in linestring.coords]
    # print('before matches')
    # matches = strtree.query(LineString(latlngpoints))    
    # print('matches: '+str(matches))
    for i, coord in enumerate(linestring.coords):
      # start = time.time()
      # if (len(mp.geoms) > 0):
      points = self.centerPoints(coord, mp.centroid, mp.geoms)
      displacedpoints = self.displacePoints(pDist, points)
        # activepoints, onlandpoints = self.onlandPoints(mp.geoms, displacedpoints, matches)
        # deactivepoints += onlandpoints
      # print('active: '+str(len(activepoints)))
      # print('onland: '+str(len(onlandpoints)))
      # end = time.time()
      # print('onland: '+str(end-start))
      # mp = geometry.MultiPoint(activepoints+deactivepoints)
      mp = geometry.MultiPoint(displacedpoints)
      level = [0] * len(mp.geoms)
      category = [2] * len(mp.geoms)
      properties = self.createProperties((i+2), timearray[i], mp.centroid, level, category)
      features.append(self.createFeature(mp, properties))
      if (i % 10 == 0):
        Cloudtrack.write(featurecollection)
        Particletrack.write(featurecollection)
      # mp = geometry.MultiPoint(activepoints)

    print('deactivepoints: '+str(len(deactivepoints)))

    return featurecollection