# -*- coding: utf-8 -*-
"""
quadkeygen.py
***************************************************************************
*                                                                         *
*   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.                                   *
*                                                                         *
***************************************************************************
"""
#  Need to be checked and tested

__author__ = "Thang Quach"
__date__ = "2024-11-20"
__copyright__ = "(L) 2024, Thang Quach"

from qgis.core import (
    QgsApplication,
    QgsProject,
    QgsCoordinateTransform,
    QgsFeatureSink,
    QgsProcessingLayerPostProcessorInterface,
    QgsProcessingParameterExtent,
    QgsProcessingParameterNumber,
    QgsProcessingException,
    QgsProcessingParameterFeatureSink,
    QgsProcessingAlgorithm,
    QgsFields,
    QgsField,
    QgsFeature,
    QgsGeometry,
    QgsWkbTypes,
    QgsCoordinateReferenceSystem,
    QgsVectorLayer,
    QgsPalLayerSettings,
    QgsVectorLayerSimpleLabeling,
)
from qgis.PyQt.QtGui import QIcon, QColor
from qgis.PyQt.QtCore import QCoreApplication, Qt
from qgis.utils import iface
from qgis.PyQt.QtCore import QVariant
import os
from ...utils.help_footer import social_links_footer
from shapely.geometry import Polygon
from vgrid.dggs import mercantile
from vgrid.utils.geometry import graticule_dggs_metrics
from ...settings import settings
from vgrid.utils.io import validate_coordinate
from ...utils.latlon import epsg4326


class QuadkeyGen(QgsProcessingAlgorithm):
    EXTENT = "EXTENT"
    RESOLUTION = "RESOLUTION"
    OUTPUT = "OUTPUT"

    LOC = QgsApplication.locale()[:2]

    def translate(self, string):
        return QCoreApplication.translate("Processing", string)

    def tr(self, *string):
        # Translate to Vietnamese: arg[0] - English (translate), arg[1] - Vietnamese
        if self.LOC == "vi":
            if len(string) == 2:
                return string[1]
            else:
                return self.translate(string[0])
        else:
            return self.translate(string[0])

    def createInstance(self):
        return QuadkeyGen()

    def name(self):
        return "quadkey_gen"

    def icon(self):
        return QIcon(
            os.path.join(
                os.path.dirname(os.path.dirname(__file__)),
                "../images/generator/grid_quad.svg",
            )
        )

    def displayName(self):
        return self.tr("Quadkey", "Quadkey")

    def group(self):
        return self.tr("Generator", "Generator")

    def groupId(self):
        return "generator"

    def tags(self):
        return self.tr("Quadkey, generator").split(",")

    txt_en = "Quadkey DGGS Generator"
    txt_vi = "Quadkey DGGS Generator"
    figure = "../images/tutorial/grid_tilecode.png"

    def shortHelpString(self):
        footer = (
            '''<div align="center">
                      <img src="'''
            + os.path.join(os.path.dirname(os.path.dirname(__file__)), self.figure)
            + """">
                    </div>
                    <div align="right">
                      <p align="right">
                      <b>"""
            + self.tr("Author: Thang Quach", "Author: Thang Quach")
            + """</b>
                      </p>"""
            + social_links_footer()
            + """
                    </div>
                    """
        )
        return self.tr(self.txt_en, self.txt_vi) + footer

    def initAlgorithm(self, config=None):
        param = QgsProcessingParameterExtent(
            self.EXTENT, self.tr("Grid extent"), optional=True
        )
        self.addParameter(param)

        min_res, max_res, _ = settings.getResolution("Quadkey")
        param = QgsProcessingParameterNumber(
            self.RESOLUTION,
            self.tr(f"Resolution/ zoom level [{min_res}..{max_res}]"),
            QgsProcessingParameterNumber.Integer,
            defaultValue=1,
            minValue=min_res,
            maxValue=max_res,
            optional=False,
        )
        self.addParameter(param)

        param = QgsProcessingParameterFeatureSink(self.OUTPUT, "Quadkey")
        self.addParameter(param)

    def prepareAlgorithm(self, parameters, context, feedback):
        self.resolution = self.parameterAsInt(parameters, self.RESOLUTION, context)
        # Get the extent parameter
        self.canvas_extent = self.parameterAsExtent(parameters, self.EXTENT, context)
        # Ensure that when RESOLUTION > 4, the extent must be set
        if self.resolution > 9 and (
            self.canvas_extent is None or self.canvas_extent.isEmpty()
        ):
            feedback.reportError(
                "For performance reason, when resolution is greater than 9, the canvas extent must be set."
            )
            return False

        return True

    def outputFields(self):
        output_fields = QgsFields()
        output_fields.append(QgsField("quadkey", QVariant.String))
        output_fields.append(QgsField("resolution", QVariant.Int))
        output_fields.append(QgsField("center_lat", QVariant.Double))
        output_fields.append(QgsField("center_lon", QVariant.Double))
        output_fields.append(QgsField("cell_width", QVariant.Double))
        output_fields.append(QgsField("cell_height", QVariant.Double))
        output_fields.append(QgsField("cell_area", QVariant.Double))
        output_fields.append(QgsField("cell_perimeter", QVariant.Double))
        return output_fields

    def processAlgorithm(self, parameters, context, feedback):
        fields = self.outputFields()

        (sink, dest_id) = self.parameterAsSink(
            parameters,
            self.OUTPUT,
            context,
            fields,
            QgsWkbTypes.Polygon,
            QgsCoordinateReferenceSystem("EPSG:4326"),
        )

        if sink is None:
            raise QgsProcessingException("Failed to create output sink")

        canvas_crs = QgsProject.instance().crs()
        if self.canvas_extent is None or self.canvas_extent.isEmpty():
            # min_lon, min_lat, max_lon, max_lat =  -180.0, -85.05112878, 180.0, 85.05112878
            min_lon, min_lat, max_lon, max_lat = -180, -90, 180, 90
        else:
            try:
                min_lon, min_lat, max_lon, max_lat = (
                    self.canvas_extent.xMinimum(),
                    self.canvas_extent.yMinimum(),
                    self.canvas_extent.xMaximum(),
                    self.canvas_extent.yMaximum(),
                )
                # Transform extent to EPSG:4326 if needed
                if epsg4326 != canvas_crs:
                    trans_to_4326 = QgsCoordinateTransform(
                        canvas_crs, epsg4326, QgsProject.instance()
                    )
                    self.canvas_extent = trans_to_4326.transform(self.canvas_extent)
                    min_lon, min_lat, max_lon, max_lat = (
                        self.canvas_extent.xMinimum(),
                        self.canvas_extent.yMinimum(),
                        self.canvas_extent.xMaximum(),
                        self.canvas_extent.yMaximum(),
                    )
            except Exception:
                # min_lon, min_lat, max_lon, max_lat = -180.0, -85.05112878, 180.0, 85.05112878
                min_lon, min_lat, max_lon, max_lat = -180, -90, 180, 90

        min_lon, min_lat, max_lon, max_lat = validate_coordinate(
            min_lon, min_lat, max_lon, max_lat
        )

        tiles = list(
            mercantile.tiles(min_lon, min_lat, max_lon, max_lat, self.resolution)
        )

        total_cells = len(tiles)
        feedback.pushInfo(f"Total cells to be generated: {total_cells}.")

        # Iterate over each tile to create features
        for idx, tile in enumerate(tiles):
            if feedback.isCanceled():
                break
            progress = int((idx / total_cells) * 100)
            feedback.setProgress(progress)
            # Get the tile's bounding box in geographic coordinates
            bounds = mercantile.bounds(tile)
            # Create a Shapely polygon
            cell_polygon = Polygon(
                [
                    (bounds.west, bounds.south),
                    (bounds.east, bounds.south),
                    (bounds.east, bounds.north),
                    (bounds.west, bounds.north),
                    (bounds.west, bounds.south),  # Closing the polygon
                ]
            )
            cell_geometry = QgsGeometry.fromWkt(cell_polygon.wkt)
            quadkey_feature = QgsFeature()
            quadkey_feature.setGeometry(cell_geometry)

            quadkey_id = mercantile.quadkey(tile)
            (
                center_lat,
                center_lon,
                cell_width,
                cell_height,
                cell_area,
                cell_perimeter,
            ) = graticule_dggs_metrics(cell_polygon)
            quadkey_feature.setAttributes(
                [
                    quadkey_id,
                    self.resolution,
                    center_lat,
                    center_lon,
                    cell_width,
                    cell_height,
                    cell_area,
                    cell_perimeter,
                ]
            )
            sink.addFeature(quadkey_feature, QgsFeatureSink.FastInsert)

        feedback.pushInfo("Quadkey DGGS generation completed.")
        if context.willLoadLayerOnCompletion(dest_id):
            lineColor = settings.quadkeyColor
            fontColor = QColor("#000000")
            context.layerToLoadOnCompletionDetails(dest_id).setPostProcessor(
                StylePostProcessor.create(lineColor, fontColor)
            )

        return {self.OUTPUT: dest_id}


class StylePostProcessor(QgsProcessingLayerPostProcessorInterface):
    instance = None
    line_color = None
    font_color = None

    def __init__(self, line_color, font_color):
        self.line_color = line_color
        self.font_color = font_color
        super().__init__()

    def postProcessLayer(self, layer, context, feedback):
        if not isinstance(layer, QgsVectorLayer):
            return
        sym = layer.renderer().symbol().symbolLayer(0)
        sym.setBrushStyle(Qt.BrushStyle.NoBrush)
        sym.setStrokeColor(self.line_color)
        if settings.gridLabel:
            label = QgsPalLayerSettings()
            label.fieldName = "quadkey"
            format = label.format()
            format.setColor(self.font_color)
            format.setSize(8)
            label.setFormat(format)
            labeling = QgsVectorLayerSimpleLabeling(label)
            layer.setLabeling(labeling)
            layer.setLabelsEnabled(True)

        iface.layerTreeView().refreshLayerSymbology(layer.id())
        root = QgsProject.instance().layerTreeRoot()
        layer_node = root.findLayer(layer.id())
        if layer_node:
            layer_node.setCustomProperty("showFeatureCount", True)

        # iface.mapCanvas().setExtent(layer.extent())
        iface.mapCanvas().refresh()

    # Hack to work around sip bug!
    @staticmethod
    def create(line_color, font_color) -> "StylePostProcessor":
        """
        Returns a new instance of the post processor, keeping a reference to the sip
        wrapper so that sip doesn't get confused with the Python subclass and call
        the base wrapper implementation instead... ahhh sip, you wonderful piece of sip
        """
        StylePostProcessor.instance = StylePostProcessor(line_color, font_color)
        return StylePostProcessor.instance
