QGIS/python/plugins/processing/algs/qgis/CheckValidity.py

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

"""
***************************************************************************
    CheckValidity.py
    ---------------------
    Date                 : May 2015
    Copyright            : (C) 2015 by Arnaud Morvan
    Email                : arnaud dot morvan at camptocamp 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__ = 'Arnaud Morvan'
__date__ = 'May 2015'
__copyright__ = '(C) 2015, Arnaud Morvan'

# This will get replaced with a git SHA1 when you do a git archive323

__revision__ = '$Format:%H$'

import os

from qgis.PyQt.QtGui import QIcon
from qgis.PyQt.QtCore import QVariant

from qgis.core import (QgsSettings,
                       QgsGeometry,
                       QgsFeature,
                       QgsField,
                       QgsFeatureRequest,
                       QgsFeatureSink,
                       QgsWkbTypes,
                       QgsProcessingUtils,
                       QgsFields,
                       QgsProcessingFeatureSource,
                       QgsProcessingParameterFeatureSource,
                       QgsProcessingParameterEnum,
                       QgsProcessingParameterFeatureSink,
                       QgsProcessingOutputVectorLayer,
                       QgsProcessingParameterDefinition,
                       QgsProcessingOutputNumber
                       )
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm

settings_method_key = "/qgis/digitizing/validate_geometries"
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]


class CheckValidity(QgisAlgorithm):

    INPUT_LAYER = 'INPUT_LAYER'
    METHOD = 'METHOD'
    VALID_OUTPUT = 'VALID_OUTPUT'
    VALID_COUNT = 'VALID_COUNT'
    INVALID_OUTPUT = 'INVALID_OUTPUT'
    INVALID_COUNT = 'INVALID_COUNT'
    ERROR_OUTPUT = 'ERROR_OUTPUT'
    ERROR_COUNT = 'ERROR_COUNT'

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

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

    def __init__(self):
        super().__init__()
        self.methods = [self.tr('The one selected in digitizing settings'),
                        'QGIS',
                        'GEOS']

        self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT_LAYER,
                                                              self.tr('Input layer')))
        self.addParameter(QgsProcessingParameterEnum(self.METHOD,
                                                     self.tr('Method'), self.methods))

        self.addParameter(QgsProcessingParameterFeatureSink(self.VALID_OUTPUT, self.tr('Valid output'), QgsProcessingParameterDefinition.TypeVectorAny, '', True))
        self.addOutput(QgsProcessingOutputVectorLayer(self.VALID_OUTPUT, self.tr('Valid output')))
        self.addOutput(QgsProcessingOutputNumber(self.VALID_COUNT, self.tr('Count of valid features')))

        self.addParameter(QgsProcessingParameterFeatureSink(self.INVALID_OUTPUT, self.tr('Invalid output'), QgsProcessingParameterDefinition.TypeVectorAny, '', True))
        self.addOutput(QgsProcessingOutputVectorLayer(self.INVALID_OUTPUT, self.tr('Invalid output')))
        self.addOutput(QgsProcessingOutputNumber(self.INVALID_COUNT, self.tr('Count of invalid features')))

        self.addParameter(QgsProcessingParameterFeatureSink(self.ERROR_OUTPUT, self.tr('Error output'), QgsProcessingParameterDefinition.TypeVectorAny, '', True))
        self.addOutput(QgsProcessingOutputVectorLayer(self.ERROR_OUTPUT, self.tr('Error output')))
        self.addOutput(QgsProcessingOutputNumber(self.ERROR_COUNT, self.tr('Count of errors')))

        self.method = None
        self.source = None
        self.valid_output_sink = None
        self.valid_output_dest_id = None
        self.valid_count = 0
        self.invalid_output_sink = None
        self.invalid_output_dest_id = None
        self.invalid_count = 0
        self.error_output_sink = None
        self.error_output_dest_id = None
        self.error_count = 0

    def name(self):
        return 'checkvalidity'

    def displayName(self):
        return self.tr('Check validity')

    def prepareAlgorithm(self, parameters, context, feedback):
        method_param = self.parameterAsEnum(parameters, self.METHOD, context)
        if method_param == 0:
            settings = QgsSettings()
            self.method = int(settings.value(settings_method_key, 0)) - 1
            if self.method < 0:
                self.method = 0
        else:
            self.method = method_param - 1

        self.source = self.parameterAsSource(parameters, self.INPUT_LAYER, context)

        (self.valid_output_sink, self.valid_output_dest_id) = self.parameterAsSink(parameters, self.VALID_OUTPUT,
                                                                                   context,
                                                                                   self.source.fields(),
                                                                                   self.source.wkbType(),
                                                                                   self.source.sourceCrs())

        invalid_fields = self.source.fields()
        invalid_fields.append(QgsField('_errors', QVariant.String, 'string', 255))
        (self.invalid_output_sink, self.invalid_output_dest_id) = self.parameterAsSink(parameters, self.INVALID_OUTPUT,
                                                                                       context,
                                                                                       invalid_fields,
                                                                                       self.source.wkbType(),
                                                                                       self.source.sourceCrs())

        error_fields = QgsFields()
        error_fields.append(QgsField('message', QVariant.String, 'string', 255))
        (self.error_output_sink, self.error_output_dest_id) = self.parameterAsSink(parameters, self.ERROR_OUTPUT, context,
                                                                                   error_fields, QgsWkbTypes.Point,
                                                                                   self.source.sourceCrs())
        return True

    def processAlgorithm(self, context, feedback):
        features = self.source.getFeatures(QgsFeatureRequest(), QgsProcessingFeatureSource.FlagSkipGeometryValidityChecks)
        total = 100.0 / self.source.featureCount() if self.source.featureCount() else 0
        for current, inFeat in enumerate(features):
            if feedback.isCanceled():
                break
            geom = inFeat.geometry()
            attrs = inFeat.attributes()

            valid = True
            if not geom.isNull() and not geom.isEmpty():
                errors = list(geom.validateGeometry(self.method))
                if errors:
                    # QGIS method return a summary at the end
                    if self.method == 1:
                        errors.pop()
                    valid = False
                    reasons = []
                    for error in errors:
                        errFeat = QgsFeature()
                        error_geom = QgsGeometry.fromPoint(error.where())
                        errFeat.setGeometry(error_geom)
                        errFeat.setAttributes([error.what()])
                        if self.error_output_sink:
                            self.error_output_sink.addFeature(errFeat, QgsFeatureSink.FastInsert)
                        self.error_count += 1

                        reasons.append(error.what())

                    reason = "\n".join(reasons)
                    if len(reason) > 255:
                        reason = reason[:252] + '...'
                    attrs.append(reason)

            outFeat = QgsFeature()
            outFeat.setGeometry(geom)
            outFeat.setAttributes(attrs)

            if valid:
                if self.valid_output_sink:
                    self.valid_output_sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                self.valid_count += 1

            else:
                if self.invalid_output_sink:
                    self.invalid_output_sink.addFeature(outFeat, QgsFeatureSink.FastInsert)
                self.invalid_count += 1

            feedback.setProgress(int(current * total))
        return True

    def postProcessAlgorithm(self, context, feedback):
        results = {
            self.VALID_COUNT: self.valid_count,
            self.INVALID_COUNT: self.invalid_count,
            self.ERROR_COUNT: self.error_count
        }
        if self.valid_output_sink:
            results[self.VALID_OUTPUT] = self.valid_output_dest_id
        if self.invalid_output_sink:
            results[self.INVALID_OUTPUT] = self.invalid_output_dest_id
        if self.error_output_sink:
            results[self.ERROR_OUTPUT] = self.error_output_dest_id
        return results