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

"""
***************************************************************************
    SimplifyGeometries.py
    ---------------------
    Date                 : August 2012
    Copyright            : (C) 2012 by Victor Olaya
    Email                : volayaf 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__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'

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

__revision__ = '$Format:%H$'

import os

from qgis.PyQt.QtGui import QIcon

from qgis.core import (QgsMapToPixelSimplifier,
                       QgsMessageLog,
                       QgsProcessingUtils)

from processing.algs.qgis import QgisAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterNumber
from processing.core.parameters import ParameterSelection
from processing.core.outputs import OutputVector
from processing.tools import dataobjects

pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]


class SimplifyGeometries(QgisAlgorithm):

    INPUT = 'INPUT'
    TOLERANCE = 'TOLERANCE'
    OUTPUT = 'OUTPUT'
    METHOD = 'METHOD'

    def icon(self):
        return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'simplify.png'))

    def group(self):
        return self.tr('Vector geometry tools')

    def __init__(self):
        super().__init__()
        self.addParameter(ParameterVector(self.INPUT,
                                          self.tr('Input layer'),
                                          [dataobjects.TYPE_VECTOR_POLYGON, dataobjects.TYPE_VECTOR_LINE]))
        self.methods = [self.tr('Distance (Douglas-Peucker)'),
                        'Snap to grid',
                        'Area (Visvalingam)']
        self.addParameter(ParameterSelection(
            self.METHOD,
            self.tr('Simplification method'),
            self.methods, default=0))
        self.addParameter(ParameterNumber(self.TOLERANCE,
                                          self.tr('Tolerance'), 0.0, 10000000.0, 1.0))

        self.addOutput(OutputVector(self.OUTPUT, self.tr('Simplified')))

    def name(self):
        return 'simplifygeometries'

    def displayName(self):
        return self.tr('Simplify geometries')

    def processAlgorithm(self, parameters, context, feedback):
        layer = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.INPUT), context)
        tolerance = self.getParameterValue(self.TOLERANCE)
        method = self.getParameterValue(self.METHOD)

        pointsBefore = 0
        pointsAfter = 0

        writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(layer.fields(), layer.wkbType(),
                                                                     layer.crs(), context)

        features = QgsProcessingUtils.getFeatures(layer, context)
        total = 100.0 / QgsProcessingUtils.featureCount(layer, context)

        if method != 0:
            simplifier = QgsMapToPixelSimplifier(QgsMapToPixelSimplifier.SimplifyGeometry, tolerance, method)

        for current, input_feature in enumerate(features):
            out_feature = input_feature
            if input_feature.geometry():
                input_geometry = input_feature.geometry()
                pointsBefore += input_geometry.geometry().nCoordinates()

                if method == 0:  # distance
                    output_geometry = input_geometry.simplify(tolerance)
                else:
                    output_geometry = simplifier.simplify(input_geometry)

                pointsAfter += output_geometry.geometry().nCoordinates()
                out_feature.setGeometry(output_geometry)
            writer.addFeature(out_feature)
            feedback.setProgress(int(current * total))

        del writer

        QgsMessageLog.logMessage(self.tr('Simplify: Input geometries have been simplified from {0} to {1} points').format(pointsBefore, pointsAfter),
                                 self.tr('Processing'), QgsMessageLog.INFO)