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

"""
***************************************************************************
    ExtentFromLayer.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__ = '$Format:%H$'

from PyQt4.QtCore import *
from qgis.core import *
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterBoolean
from processing.core.outputs import OutputVector
from processing.tools import dataobjects, vector


class ExtentFromLayer(GeoAlgorithm):

    INPUT_LAYER = 'INPUT_LAYER'
    BY_FEATURE = 'BY_FEATURE'

    OUTPUT = 'OUTPUT'

    #==========================================================================
    #def getIcon(self):
    #   return QIcon(os.path.dirname(__file__) + "/icons/layer_extent.png")
    #==========================================================================

    def defineCharacteristics(self):
        self.name = 'Polygon from layer extent'
        self.group = 'Vector general tools'

        self.addParameter(ParameterVector(self.INPUT_LAYER, 'Input layer',
                          [ParameterVector.VECTOR_TYPE_ANY]))
        self.addParameter(ParameterBoolean(self.BY_FEATURE,
                          'Calculate extent for each feature separately',
                          False))

        self.addOutput(OutputVector(self.OUTPUT, 'Output layer'))

    def processAlgorithm(self, progress):
        layer = dataobjects.getObjectFromUri(
                self.getParameterValue(self.INPUT_LAYER))
        byFeature = self.getParameterValue(self.BY_FEATURE)

        fields = [
            QgsField('MINX', QVariant.Double),
            QgsField('MINY', QVariant.Double),
            QgsField('MAXX', QVariant.Double),
            QgsField('MAXY', QVariant.Double),
            QgsField('CNTX', QVariant.Double),
            QgsField('CNTY', QVariant.Double),
            QgsField('AREA', QVariant.Double),
            QgsField('PERIM', QVariant.Double),
            QgsField('HEIGHT', QVariant.Double),
            QgsField('WIDTH', QVariant.Double),
            ]

        writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fields,
                QGis.WKBPolygon, layer.crs())

        if byFeature:
            self.featureExtent(layer, writer, progress)
        else:
            self.layerExtent(layer, writer, progress)

        del writer

    def layerExtent(self, layer, writer, progress):
        rect = layer.extent()
        minx = rect.xMinimum()
        miny = rect.yMinimum()
        maxx = rect.xMaximum()
        maxy = rect.yMaximum()
        height = rect.height()
        width = rect.width()
        cntx = minx + width / 2.0
        cnty = miny + height / 2.0
        area = width * height
        perim = 2 * width + 2 * height

        rect = [QgsPoint(minx, miny), QgsPoint(minx, maxy), QgsPoint(maxx,
                maxy), QgsPoint(maxx, miny), QgsPoint(minx, miny)]
        geometry = QgsGeometry().fromPolygon([rect])
        feat = QgsFeature()
        feat.setGeometry(geometry)
        attrs = [
            minx,
            miny,
            maxx,
            maxy,
            cntx,
            cnty,
            area,
            perim,
            height,
            width,
            ]
        feat.setAttributes(attrs)
        writer.addFeature(feat)

    def featureExtent(self, layer, writer, progress):
        current = 0
        features = vector.features(layer)
        total = 100.0 / float(len(features))
        feat = QgsFeature()
        for f in features:
            rect = f.geometry().boundingBox()
            minx = rect.xMinimum()
            miny = rect.yMinimum()
            maxx = rect.xMaximum()
            maxy = rect.yMaximum()
            height = rect.height()
            width = rect.width()
            cntx = minx + width / 2.0
            cnty = miny + height / 2.0
            area = width * height
            perim = 2 * width + 2 * height
            rect = [QgsPoint(minx, miny), QgsPoint(minx, maxy), QgsPoint(maxx,
                    maxy), QgsPoint(maxx, miny), QgsPoint(minx, miny)]

            geometry = QgsGeometry().fromPolygon([rect])
            feat.setGeometry(geometry)
            attrs = [
                minx,
                miny,
                maxx,
                maxy,
                cntx,
                cnty,
                area,
                perim,
                height,
                width,
                ]
            feat.setAttributes(attrs)

            writer.addFeature(feat)
            current += 1
            progress.setPercentage(int(current * total))