from typing import Optional

import numpy as np
from scipy.interpolate import LinearNDInterpolator

from bivariatecolorrasterrendererapp.bivariatecolorrasterrenderer import BivariateColorRasterRenderer
from enmapbox.qgispluginsupport.qps.pyqtgraph.pyqtgraph import PlotWidget, ImageItem
from enmapbox.qgispluginsupport.qps.utils import SpatialExtent
from enmapbox.typeguard import typechecked
from enmapboxprocessing.rasterreader import RasterReader
from qgis.PyQt.QtGui import QColor
from qgis.PyQt.QtWidgets import QWidget, QToolButton, QCheckBox, QMainWindow, QComboBox, QMenu, QAction, QPushButton, \
    QLineEdit, QRadioButton
from qgis.PyQt.uic import loadUi
from qgis.core import QgsRasterLayer, QgsMapLayerProxyModel, QgsMapSettings
from qgis.gui import QgsMapCanvas, QgsRasterBandComboBox, QgsDoubleSpinBox, QgsMapLayerComboBox, QgsColorButton, \
    QgsSpinBox


@typechecked
class ColorPlanePlotWidget(PlotWidget):
    def __init__(self, *args):
        PlotWidget.__init__(self, parent=None, background='#f0f0f0')
        self.setDefaultPadding(padding=0.02)


@typechecked
class BivariateColorRasterRendererDialog(QMainWindow):
    mLayer: QgsMapLayerComboBox
    mBand1: QgsRasterBandComboBox
    mBand2: QgsRasterBandComboBox
    mMin1: QLineEdit
    mMin2: QLineEdit
    mMax1: QLineEdit
    mMax2: QLineEdit
    mColor1: QgsColorButton
    mColor2: QgsColorButton
    mColor3: QgsColorButton
    mColor4: QgsColorButton
    mUseColor2: QCheckBox
    mPlot: ColorPlanePlotWidget
    mMenu: QPushButton
    mMode: QComboBox
    mClasses: QgsSpinBox
    mMinMaxUser: QRadioButton
    mMinMaxPercentile: QRadioButton
    mP1: QgsDoubleSpinBox
    mP2: QgsDoubleSpinBox
    mExtent: QComboBox
    mAccuracy: QComboBox

    mLiveUpdate: QCheckBox
    mApply: QToolButton

    ContinuouseMode, EqualIntervalMode, QuantileMode = 0, 1, 2
    EstimatedAccuracy, ActualAccuracy = 0, 1
    WholeRasterExtent, CurrentCanvasExtent = 0, 1

    def __init__(self, parent=None):
        QWidget.__init__(self, parent)
        loadUi(__file__.replace('.py', '.ui'), self)

        from enmapbox.gui.enmapboxgui import EnMAPBox
        self.enmapBox = EnMAPBox.instance()
        self.colorPlane: np.ndarray

        self.mMapCanvas: Optional[QgsMapCanvas] = None
        self.mLayer.setProject(self.enmapBox.project())
        self.mLayer.setFilters(QgsMapLayerProxyModel.RasterLayer)
        self.mP1.setClearValue(self.mP1.value())
        self.mP2.setClearValue(self.mP2.value())

        self.predefinedColorPlanes = {
            'Katja Kowalski 1': ['#0198eb', '#830050', '#bebebf', '#fee413'],
            'Joshua Stevens 1': ['#64acbe', '#574249', '#e8e8e8', '#c85a5a'],
            'Joshua Stevens 2': ['#be64ac', '#3b4994', '#e8e8e8', '#5ac8c8'],
            'Joshua Stevens 3': ['#73ae80', '#2a5a5b', '#e8e8e8', '#6c83b5'],
            'Joshua Stevens 4': ['#9972af', '#804d36', '#e8e8e8', '#c8b35a'],
            'ArcMap BrBG': ['#a85e18', '#537440', '#f2f7f5', '#00856f'],
            'ArcMap BrBu_Dk': ['#c68023', '#463333', '#cccccc', '#5a84bc'],
            'ArcMap BrBu_Lt': ['#c58225', '#8d866c', '#cccccc', '#5785ba'],
            'ArcMap BuOr': ['#4a9fc2', '#364f4a', '#f3f3f3', '#f4b100'],
            'ArcMap PiGn': ['#d4188a', '#8d635a', '#f7f7f7', '#49aa25'],
            'ArcMap PuGn': ['#793293', '#405164', '#f6f6f6', '#018738'],
            'ArcMap PuOr': ['#a85e18', '#537440', '#f2f7f5', '#e85f03'],
            'ArcMap RdBu': ['#c90223', '#683769', '#f7f7f7', '#0470b2'],
            'ArcMap PiBu': ['#b94a8d', '#4e428b', '#cdc5da', '#0b94c9'],
            'ArcMap RdGy': ['#cb0022', '#993245', '#ffffff', '#656565'],
            'ArcMap RdYlBu': ['#d31820', '#85486a', '#feffbf', '#2c7ab8'],
            'ArcMap RdYlGn': ['#d81b1f', '#77572e', '#feffc1', '#199942']
        }
        menu = QMenu()
        for name in self.predefinedColorPlanes:
            menu.addAction(name, self.onColorPlaneSelected)
            # todo: make icons; see https://stackoverflow.com/questions/55394894/update-qpushbutton-icon-from-an-numpy-array-dont-work
        self.mMenu.setMenu(menu)

        self.mLayer.layerChanged.connect(self.onLayerChanged)
        self.mBand1.bandChanged.connect(self.onLiveUpdate)
        self.mBand2.bandChanged.connect(self.onLiveUpdate)
        self.mColor1.colorChanged.connect(self.onColorChanged)
        self.mColor2.colorChanged.connect(self.onColorChanged)
        self.mColor3.colorChanged.connect(self.onColorChanged)
        self.mColor4.colorChanged.connect(self.onColorChanged)
        self.mUseColor2.stateChanged.connect(self.onColorChanged)
        self.mMode.currentIndexChanged.connect(self.onColorChanged)
        self.mClasses.valueChanged.connect(self.onColorChanged)
        self.mP1.valueChanged.connect(self.onLiveUpdate)
        self.mP2.valueChanged.connect(self.onLiveUpdate)
        self.mExtent.currentIndexChanged.connect(self.onLiveUpdate)
        self.mAccuracy.currentIndexChanged.connect(self.onLiveUpdate)

        self.mApply.clicked.connect(self.onApplyClicked)

        self.onColorChanged()

    def currentLayer(self) -> Optional[QgsRasterLayer]:
        return self.mLayer.currentLayer()

    def currentExtent(self) -> Optional[SpatialExtent]:
        layer = self.currentLayer()
        if layer is None:
            return None

        if self.mExtent.currentIndex() == self.WholeRasterExtent:
            return SpatialExtent(layer.crs(), layer.extent())
        elif self.mExtent.currentIndex() == self.CurrentCanvasExtent:
            mapSettings: QgsMapSettings = self.mMapCanvas.mapSettings()
            return SpatialExtent(mapSettings.destinationCrs(), self.mMapCanvas.extent()).toCrs(layer.crs())
        else:
            raise ValueError()

    def currentSampleSize(self) -> int:
        if self.mAccuracy.currentIndex() == self.EstimatedAccuracy:
            return int(QgsRasterLayer.SAMPLE_SIZE)
        elif self.mAccuracy.currentIndex() == self.ActualAccuracy:
            return 0  # use all pixel
        else:
            raise ValueError()

    def currentRenderer(self) -> Optional[BivariateColorRasterRenderer]:
        layer = self.currentLayer()
        if layer is None:
            return None

        band1 = self.mBand1.currentBand()
        band2 = self.mBand2.currentBand()
        if -1 in [band1, band2]:
            return None

        quantile_range = self.mP1.value(), self.mP2.value()

        extent = self.currentExtent()
        extent = extent.intersect(layer.extent())
        sampleSize = self.currentSampleSize()

        reader = RasterReader(layer)
        width, height = reader.samplingWidthAndHeight(band1, extent, sampleSize)
        array = reader.array(bandList=[band1, band2], width=width, height=height, boundingBox=extent)
        maskArray = np.all(reader.maskArray(array, [band1, band2]), axis=0)
        array1, array2 = array
        values1 = array1[maskArray]
        values2 = array2[maskArray]

        if len(values1) == 0:
            return None

        if self.mMinMaxPercentile.isChecked():
            min1, max1 = np.percentile(values1, quantile_range)
            min2, max2 = np.percentile(values2, quantile_range)
            self.mMin1.setText(str(min1))
            self.mMin2.setText(str(min2))
            self.mMax1.setText(str(max1))
            self.mMax2.setText(str(max2))

        min1 = float(self.mMin1.text())
        min2 = float(self.mMin2.text())
        max1 = float(self.mMax1.text())
        max2 = float(self.mMax2.text())

        mode = self.mMode.currentIndex()
        if mode in [self.ContinuouseMode, self.EqualIntervalMode]:
            binEdges1 = np.linspace(min1, max1, self.colorPlane.shape[0] + 1)
            binEdges2 = np.linspace(min2, max2, self.colorPlane.shape[1] + 1)
        else:
            binEdges1 = np.percentile(
                values1[(min1 <= values1) * (values1 <= max1)],
                np.linspace(0, 100, self.colorPlane.shape[0] + 1)
            )
            binEdges2 = np.percentile(
                values2[(min2 <= values2) * (values1 <= max2)],
                np.linspace(0, 100, self.colorPlane.shape[1] + 1)
            )

        # update plot
        ax = self.mPlot.getAxis('bottom')
        ay = self.mPlot.getAxis('left')
        if mode == self.ContinuouseMode:
            ax.setTicks([[(0, smartRound(binEdges1[0])), (len(binEdges1), smartRound(binEdges1[-1]))]])
            ay.setTicks([[(0, smartRound(binEdges2[0])), (len(binEdges2), smartRound(binEdges2[-1]))]])
        else:
            ax.setTicks([[(i, smartRound(value)) for i, value in enumerate(binEdges1)]])
            ay.setTicks([[(i, smartRound(value)) for i, value in enumerate(binEdges2)]])
        self.mPlot.setLabel(axis='bottom', text=reader.bandName(band1))
        self.mPlot.setLabel(axis='left', text=reader.bandName(band2))

        # make renderer
        renderer = BivariateColorRasterRenderer()
        renderer.setRange(min1, min2, max1, max2)
        renderer.setBands(band1, band2)
        renderer.setColorPlane(self.colorPlane)
        renderer.setBinEdges(binEdges1, binEdges2)

        return renderer

    def onLayerChanged(self):

        # get map canvas
        self.mMapCanvas = None
        layer = self.currentLayer()
        for mapDock in self.enmapBox.dockManager().mapDocks():
            if layer in mapDock.mapCanvas().layers():
                self.mMapCanvas = mapDock.mapCanvas()
                break

        # update gui
        self.mBand1.setLayer(layer)
        self.mBand2.setLayer(layer)
        self.mBand1.setBand(-1)
        self.mBand2.setBand(-1)

        if layer is None:
            return

        renderer = layer.renderer()
        if isinstance(renderer, BivariateColorRasterRenderer):
            self.mBand1.setBand(renderer.band1)
            self.mBand2.setBand(renderer.band2)
        else:
            self.mBand1.setBand(1)
            self.mBand2.setBand(min(2, layer.bandCount()))

    def onColorChanged(self):
        mode = self.mMode.currentIndex()

        colors = [mColor.color() for mColor in [self.mColor1, self.mColor2, self.mColor3, self.mColor4]]

        if not self.mUseColor2.isChecked():
            color2 = QColor(
                int((colors[0].red() + colors[3].red()) / 2),
                int((colors[0].green() + colors[3].green()) / 2),
                int((colors[0].blue() + colors[3].blue()) / 2),
            )
            colors[1] = color2

        colorsEdges = np.reshape([np.array([color.red(), color.green(), color.blue()]) for color in colors], (2, 2, 3))

        if mode == self.ContinuouseMode:
            self.mClasses.setEnabled(False)
            classes = 256
        else:
            self.mClasses.setEnabled(True)
            classes = self.mClasses.value()

        x, y = np.meshgrid([1, classes], [1, classes])
        Xnew, Ynew = np.meshgrid(np.linspace(1, classes, classes), np.linspace(1, classes, classes))
        points = list(zip(x.flat, y.flat))
        fRed = LinearNDInterpolator(points, list(colorsEdges[:, :, 0].flat))
        redPlane = fRed(Xnew, Ynew)
        fGreen = LinearNDInterpolator(points, list(colorsEdges[:, :, 1].flat))
        greenPlane = fGreen(Xnew, Ynew)
        fBlue = LinearNDInterpolator(points, list(colorsEdges[:, :, 2].flat))
        bluePlane = fBlue(Xnew, Ynew)
        self.colorPlane = np.transpose((redPlane, greenPlane, bluePlane), (1, 2, 0))

        self.mPlot.clear()

        imageItem = ImageItem()
        imageItem.setImage(
            self.colorPlane[::-1], autoHistogramRange=True, autoLevels=True, autoDownsample=True,
            axisOrder='row-major'
        )

        self.mPlot.addItem(imageItem)
        self.onApplyClicked()

    def onColorPlaneSelected(self):
        action: QAction = self.sender()
        name = action.text()
        hexcolors = self.predefinedColorPlanes[name]
        for hexcolor, mColor in zip(hexcolors, [self.mColor1, self.mColor2, self.mColor3, self.mColor4]):
            mColor.setColor(QColor(hexcolor))
        self.onColorChanged()

    def onApplyClicked(self):
        layer = self.currentLayer()
        if layer is None:
            return
        renderer = self.currentRenderer()
        if renderer is None:
            return
        layer.setRenderer(renderer)
        layer.triggerRepaint()

    def onLiveUpdate(self):
        if self.mLiveUpdate.isChecked():
            self.onApplyClicked()


@typechecked
def smartRound(value: float) -> str:
    if abs(value) < 0.1:
        return str(round(value, 4))
    elif abs(value) < 1:
        return str(round(value, 3))
    elif abs(value) < 10:
        return str(round(value, 2))
    elif abs(value) < 100:
        return str(round(value, 1))
    else:
        return str(int(round(value, 0)))
