# -*- coding: utf-8 -*-

"""
***************************************************************************
    VectorGrid.py
    ---------------------
    Date                 : September 2014
    Copyright            : (C) 2014 by Alexander Bruy
    Email                : alexander dot bruy at gmail dot com
***************************************************************************
*                                                                         *
*   This program is free software; you can redistribute it and/or modify  *
*   it under the terms of the GNU General Public License as published by  *
*   the Free Software Foundation; either version 2 of the License, or     *
*   (at your option) any later version.                                   *
*                                                                         *
***************************************************************************
"""

__author__ = 'Alexander Bruy'
__date__ = 'September 2014'
__copyright__ = '(C) 2014, Alexander Bruy'

# This will get replaced with a git SHA1 when you do a git archive

__revision__ = '$Format:%H$'

import math

from PyQt4.QtCore import *
from qgis.core import *
from qgis.utils import iface

from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterExtent
from processing.core.parameters import ParameterNumber
from processing.core.parameters import ParameterSelection
from processing.core.outputs import OutputVector
from processing.tools import vector


class VectorGrid(GeoAlgorithm):

    EXTENT = 'EXTENT'
    STEP_X = 'STEP_X'
    STEP_Y = 'STEP_Y'
    TYPE = 'TYPE'
    OUTPUT = 'OUTPUT'

    TYPES = ['Output grid as polygons',
             'Output grid as lines'
            ]

    def defineCharacteristics(self):
        self.name = 'Vector grid'
        self.group = 'Vector creation tools'
        self.addParameter(ParameterExtent(self.EXTENT, 'Grid extent'))
        self.addParameter(ParameterNumber(self.STEP_X,
            'X spacing', 0.0, 1000000000.0, 0.0001))
        self.addParameter(ParameterNumber(self.STEP_Y,
            'Y spacing', 0.0, 1000000000.0, 0.0001))
        self.addParameter(ParameterSelection(self.TYPE,
            'Grid type', self.TYPES))

        self.addOutput(OutputVector(self.OUTPUT, 'Grid'))

    def processAlgorithm(self, progress):
        extent = self.getParameterValue(self.EXTENT).split(',')
        xSpace = self.getParameterValue(self.STEP_X)
        ySpace = self.getParameterValue(self.STEP_Y)
        polygon = self.getParameterValue(self.TYPE) == 0

        bbox = QgsRectangle(float(extent[0]), float(extent[2]),
                            float(extent[1]), float(extent[3]))

        mapCRS = iface.mapCanvas().mapSettings().destinationCrs()

        fields = QgsFields()
        fields.append(QgsField('id', QVariant.Int, '', 10, 0))

        if polygon:
            fields.append(QgsField('xmin', QVariant.Double, '', 24, 15))
            fields.append(QgsField('xmax', QVariant.Double, '', 24, 15))
            fields.append(QgsField('ymin', QVariant.Double, '', 24, 15))
            fields.append(QgsField('ymax', QVariant.Double, '', 24, 15))
            fieldCount = 5
            writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
                fields, QGis.WKBPolygon, mapCRS)
        else:
            fields.append(QgsField('coord', QVariant.Double, '', 24, 15))
            fieldCount = 2
            writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
                fields, QGis.WKBPolygon, mapCRS)

        feat = QgsFeature()
        feat.initAttributes(fieldCount)
        feat.setFields(fields)
        geom = QgsGeometry()
        idVar = 0

        if not polygon:
            count = 0
            count_max = (bbox.yMaximum() - bbox.yMinimum()) / ySpace
            count_update = count_max * 0.10
            y = bbox.yMaximum()
            while y >= bbox.yMinimum():
                pt1 = QgsPoint(bbox.xMinimum(), y)
                pt2 = QgsPoint(bbox.xMaximum(), y)
                line = [pt1, pt2]
                feat.setGeometry(geom.fromPolyline(line))
                feat.setAttribute(0, idVar)
                feat.setAttribute(1, y)
                writer.addFeature(feat)
                y = y - ySpace
                idVar += 1
                count += 1
                if int(math.fmod(count, count_update)) == 0:
                    progress.setPersentage(int(count / count_max * 50))

            progress.setPersentage( 50 )
            # counters for progressbar - update every 5%
            count = 0
            count_max = (bbox.xMaximum() - bbox.xMinimum()) / xSpace
            count_update = count_max * 0.10
            x = bbox.xMinimum()
            while x <= bbox.xMaximum():
                pt1 = QgsPoint(x, bbox.yMaximum())
                pt2 = QgsPoint(x, bbox.yMinimum())
                line = [pt1, pt2]
                feat.setGeometry(geom.fromPolyline(line))
                feat.setAttribute(0, idVar)
                feat.setAttribute(1, x)
                writer.addFeature(feat)
                x = x + xOffset
                idVar += 1
                count += 1
                if int(math.fmod(count, count_update)) == 0:
                    progress.setPercentage(50 + int(count / count_max * 50))
        else:
            # counters for progressbar - update every 5%
            count = 0
            count_max = (bbox.yMaximum() - bbox.yMinimum()) / ySpace
            count_update = count_max * 0.05
            y = bbox.yMaximum()
            while y >= bbox.yMinimum():
                x = bbox.xMinimum()
                while x <= bbox.xMaximum():
                    pt1 = QgsPoint(x, y)
                    pt2 = QgsPoint(x + xSpace, y)
                    pt3 = QgsPoint(x + xSpace, y - ySpace)
                    pt4 = QgsPoint(x, y - ySpace)
                    pt5 = QgsPoint(x, y)
                    polygon = [[pt1, pt2, pt3, pt4, pt5]]
                    feat.setGeometry(geom.fromPolygon(polygon))
                    feat.setAttribute(0, idVar)
                    feat.setAttribute(1, x)
                    feat.setAttribute(2, x + xSpace)
                    feat.setAttribute(3, y - ySpace)
                    feat.setAttribute(4, y)
                    writer.addFeature(feat)
                    idVar += 1
                    x = x + xSpace
                y = y - ySpace
                count += 1
                if int(math.fmod(count, count_update)) == 0:
                    progress.setPercentage(int(count / count_max * 100))

        del writer