"""
Filename: create_tiles.py
Author: Michele Lissoni
Date: 2026-02-10
"""

"""

The QClassiPyCreateTiles class handles the "Create tiles" tab.

"""

from qgis.PyQt.QtWidgets import QWidget, QAbstractItemView, QTableWidgetItem, QFileDialog
from qgis.PyQt.QtGui import QColor, QFont
from qgis.PyQt.QtCore import Qt, QTimer

from qgis.core import *
from qgis.gui import QgsProjectionSelectionDialog

import os
import numpy as np
import pandas as pd

import shapely
from osgeo import gdal

from ..core.positions import gridPositions
from ..core.gdal_tools import generateTiff, AffineTransformer, CoordTransformXY
from ..ui.all_uis import Ui_QClassiPyCreateTiles

from .constants import Directories, Colors

layer_dir = Directories.Layer

bounds_color = QColor(Colors.Tile_Bounds)

class QClassiPyCreateTiles(QWidget):
    
    def __init__(self, parent = None, font = QFont()):
    
        """Initialization"""
    
        super(QClassiPyCreateTiles, self).__init__(parent = parent)
        
        self.ui = Ui_QClassiPyCreateTiles()
        self.ui.setupUi(self)

        for child_widget in self.findChildren(QWidget):
            child_widget.setFont(font)
        
        self.ui.crs_wkt.textChanged.connect(lambda: self.boundConvert(True)) # Other CRS WKT 
        self.ui.crs_predef.clicked.connect(self.predefCRS) # Predefined button
        self.ui.crs_wkt.setEnabled(False)
        self.ui.crs_predef.setEnabled(False)
        self.ui.bounds_box.setEnabled(False)
        
        with open(os.path.join(layer_dir, 'browsedir.txt'), 'r') as infile:
            browse_dir = infile.read()
            self.browse_dir = browse_dir if os.path.isdir(browse_dir) else ""
        
        self.ui.raster_browse.clicked.connect(self.rasterBrowse) # Choose raster, browse button
        self.ui.raster_select.clicked.connect(self.rasterSelect) # Choose raster, select button
        
        self.tile_mask_shape = None # Mask shape
        self.tile_mask_crs = None # Mask CRS
        self.tile_mask_transform = None # Mask transform
        self.tile_mask_transformer = None # Mask AffineTransformer
        
        self.bounds_layer = None # Tile bounds frame
        self.bounds_crs = None # Tile bounds CRS
        self.tile_bounds = None # Tile bounds
        self.invalid_bounds = True
        
        # Hiding error messages
        
        self.ui.raster_err.setHidden(True) 
        self.ui.crs_err.setHidden(True)
        self.ui.mask_saveerr.setHidden(True)
        self.ui.list_saveerr.setHidden(True)
        self.ui.bounds_err.setHidden(True)
        self.ui.saved_message.setHidden(True)
        
        # Tile size
        
        self.ui.tile_width.editingFinished.connect(lambda: self.WHCheck('width')) # Width
        self.ui.tile_height.editingFinished.connect(lambda: self.WHCheck('height')) # Height
        
        self.ui.save_tiles.clicked.connect(self.saveTiles) # SAVE button
        self.ui.save_tiles.setEnabled(False) 
        self.saved_tmr = None    
        
        # Mask bands table
        
        self.ui.band_table.setRowHeight(0,20)
        self.ui.band_table.setColumnWidth(0,70)
        self.ui.band_table.setSelectionMode(QAbstractItemView.SelectionMode.MultiSelection)
        self.ui.band_table.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows)
        
        # Add/remove band buttons 
        
        self.ui.band_add.clicked.connect(self.addBand)
        self.ui.band_rm.clicked.connect(self.rmBand)
        self.ui.band_table.itemChanged.connect(self.editBand)        
        
        # Mask and tile list browse buttons
        
        self.ui.mask_savebrowse.clicked.connect(lambda: self.saveBrowse('mask'))
        self.ui.list_savebrowse.clicked.connect(lambda: self.saveBrowse('list'))        
        
    def rasterBrowse(self):
    
        """Choose raster browse button"""
    
        fname=QFileDialog.getOpenFileName(self, "Open file", self.browse_dir, "")
        if fname == "":
            return
        self.browse_dir = os.path.split(fname[0])[0]
        self.ui.raster_choose.setText(fname[0])
        self.ui.raster_err.setHidden(True)
        
    def rasterSelect(self):
    
        """Choose raster select button"""
    
        self.ui.raster_err.setHidden(True)
        
        # Open raster
        
        try:
            assert os.path.exists(self.ui.raster_choose.text())
            tile_ds = gdal.Open(self.ui.raster_choose.text())        
        except:        
            self.ui.raster_err.setHidden(False)
            return
            
        band_num = self.ui.band_table.rowCount()
        band_names = [self.ui.band_table.item(row, 0).text() for row in range(0,band_num)]
        
        transform = tile_ds.GetGeoTransform()
        crs = tile_ds.GetProjection()
        shape = (tile_ds.RasterYSize, tile_ds.RasterXSize)
        
        # Remove previous bounds frame           
    
        if self.bounds_layer is not None :

            self.bounds_layer.committedGeometriesChanges.disconnect()
            QgsProject.instance().removeMapLayer(self.bounds_layer.id())
            self.bounds_layer = None
            
        # Set mask parameters

        self.tile_mask_crs = crs
        self.tile_mask_transform = transform
        self.tile_mask_shape = (tile_ds.RasterYSize, tile_ds.RasterXSize)

        tile_ds = None

        self.tile_mask_transformer = AffineTransformer(transform)        
        
        # Enable save button and Bounds group box
        
        self.ui.save_tiles.setEnabled(True)
        self.ui.bounds_box.setEnabled(True)
        
        self.ui.crs_wkt.textChanged.disconnect()
        self.ui.crs_wkt.setText("")
        self.ui.crs_wkt.textChanged.connect(lambda: self.boundConvert(True)) 
        
        self.ui.crs_wkt.setEnabled(False)
        self.ui.crs_predef.setEnabled(False)
        self.ui.crs_err.setHidden(True)    
        
        try:
            self.ui.pixel_bounds.toggled.disconnect()
            self.ui.raster_bounds.toggled.disconnect()
            self.ui.other_bounds.toggled.disconnect()
        except:
            pass
        
        # Write bound coordinates
        
        self.ui.topleft_y.setText("0")
        self.ui.topleft_x.setText("0")
        self.ui.bottomright_y.setText(str(self.tile_mask_shape[0]))
        self.ui.bottomright_x.setText(str(self.tile_mask_shape[1]))
        self.ui.topleft_y.setCursorPosition(0)
        self.ui.topleft_x.setCursorPosition(0)
        self.ui.bottomright_x.setCursorPosition(0)
        self.ui.bottomright_y.setCursorPosition(0)
        
        # Store tile bounds
        
        self.tile_bounds = [0, 0, self.tile_mask_shape[0], self.tile_mask_shape[1]]
        self.invalid_bounds = False
        
        # Create bounds frame
        
        bounds_layer=QgsVectorLayer("Polygon", 'Tile bounds', "memory")
        bounds_layer.setCrs(QgsCoordinateReferenceSystem(self.tile_mask_crs))
        
        bounds_feat=QgsFeature()
        bounds_feat.setGeometry(QgsGeometry.fromPolygonXY([[QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[1])),
                                                            QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[3])),
                                                            QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[2], self.tile_bounds[3])),
                                                            QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[2], self.tile_bounds[1])),
                                                            QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[1]))]]))
        bounds_layer.dataProvider().addFeature(bounds_feat)
        
        bounds_symbol=QgsSymbol.defaultSymbol(bounds_layer.geometryType())
        bounds_fill = QColor(bounds_color)
        bounds_fill.setAlpha(0)
        bounds_symbol.setColor(bounds_fill)
        bounds_symbol.symbolLayer(0).setStrokeWidth(1)
        bounds_symbol.symbolLayer(0).setStrokeColor(bounds_color)
        bounds_renderer = QgsSingleSymbolRenderer(bounds_symbol)
        bounds_layer.setRenderer(bounds_renderer)
        bounds_layer.triggerRepaint()

        QgsProject.instance().addMapLayer(bounds_layer)
        self.bounds_layer = bounds_layer        
        self.bounds_layer.committedGeometriesChanges.connect(self.boundPolyEdit)
        
        # Hide error messages
        
        self.ui.crs_err.setHidden(True)
        self.ui.mask_saveerr.setHidden(True)
        self.ui.list_saveerr.setHidden(True)
        self.ui.bounds_err.setHidden(True)
        
        # Connect responses to CRS changes
        
        self.ui.pixel_bounds.setChecked(True)
        
        self.ui.pixel_bounds.toggled.connect(self.boundConvert)
        self.ui.raster_bounds.toggled.connect(self.boundConvert)
        self.ui.other_bounds.toggled.connect(self.boundConvert)
        
        # Connect responses to bound coordinate changes
        
        self.ui.topleft_y.editingFinished.connect(self.boundCheck)
        self.ui.topleft_x.editingFinished.connect(self.boundCheck)
        self.ui.bottomright_x.editingFinished.connect(self.boundCheck)
        self.ui.bottomright_y.editingFinished.connect(self.boundCheck)
        
    def boundConvert(self, checked):
    
        """CRS changes"""
    
        if not checked :
            return
            
        # Pixel coordinates
            
        if self.ui.pixel_bounds.isChecked() :
        
            topleft_y, topleft_x, bottomright_y, bottomright_x = self.tile_bounds
            
            self.bounds_crs = None
            
            self.ui.crs_wkt.setEnabled(False)
            self.ui.crs_predef.setEnabled(False)
            self.ui.crs_err.setHidden(True)
            
        # Raster CRS
            
        elif self.ui.raster_bounds.isChecked() :
        
            # Convert bounds to raster CRS
            topleft_x, topleft_y = self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[1])
            bottomright_x, bottomright_y = self.tile_mask_transformer.xy(self.tile_bounds[2], self.tile_bounds[3])
            
            self.bounds_crs = self.tile_mask_crs  
            
            self.ui.crs_wkt.setEnabled(True)
            
            self.ui.crs_wkt.textChanged.disconnect()
            self.ui.crs_wkt.setText(self.tile_mask_crs)
            self.ui.crs_wkt.textChanged.connect(lambda: self.boundConvert(True)) 
            self.ui.crs_wkt.setReadOnly(True)       
            self.ui.crs_predef.setEnabled(False)
            self.ui.crs_err.setHidden(True)
            
        # Other CRS
            
        elif self.ui.other_bounds.isChecked() :
        
            # Convert bounds to raster CRS
            topleft_x, topleft_y = self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[1])
            bottomright_x, bottomright_y = self.tile_mask_transformer.xy(self.tile_bounds[2], self.tile_bounds[3])
        
            self.ui.crs_wkt.setEnabled(True)
            self.ui.crs_wkt.setReadOnly(False)
            self.ui.crs_predef.setEnabled(True)
            
            new_crs = self.ui.crs_wkt.toPlainText()
            
            if new_crs=="" :
            
                # If "Other CRS WKT" is empty, use raster CRS
            
                self.bounds_crs = self.tile_mask_crs
                self.ui.crs_wkt.textChanged.disconnect()
                self.ui.crs_wkt.setText(self.tile_mask_crs)
                self.ui.crs_wkt.textChanged.connect(lambda: self.boundConvert(True)) 
                
            else:
            
                # If "Other CRS WKT" is not empty, try to convert coordinates to other CRS, else display error
            
                try:
                
                    mask_to_other = CoordTransformXY(self.tile_mask_crs, new_crs)
                    topleft_x, topleft_y = mask_to_other.transform(topleft_x, topleft_y)
                    bottomright_x, bottomright_y = mask_to_other.transform(bottomright_x, bottomright_y)
                    
                except:
                    self.ui.topleft_y.setEnabled(False)
                    self.ui.topleft_x.setEnabled(False)
                    self.ui.bottomright_x.setEnabled(False)
                    self.ui.bottomright_y.setEnabled(False)
                    self.ui.crs_err.setHidden(False)
                    return
                    
                self.bounds_crs = new_crs
                self.ui.crs_err.setHidden(True)
                
        # Write bound coordinates 
                
        self.ui.topleft_y.setEnabled(True)
        self.ui.topleft_x.setEnabled(True)
        self.ui.bottomright_x.setEnabled(True)
        self.ui.bottomright_y.setEnabled(True)
                    
        self.ui.topleft_y.setText(str(topleft_y))
        self.ui.topleft_x.setText(str(topleft_x))
        self.ui.bottomright_x.setText(str(bottomright_x))
        self.ui.bottomright_y.setText(str(bottomright_y))
        
        self.ui.topleft_y.setCursorPosition(0)
        self.ui.topleft_x.setCursorPosition(0)
        self.ui.bottomright_x.setCursorPosition(0)
        self.ui.bottomright_y.setCursorPosition(0)      
            
    def boundCheck(self):
    
        """Bounds edited"""

        # Retrieve bounds in pixel coordinates
        try:
            topleft_y = float(self.ui.topleft_y.text())
            topleft_x = float(self.ui.topleft_x.text())
            bottomright_y = float(self.ui.bottomright_y.text())
            bottomright_x = float(self.ui.bottomright_x.text())
        except:
            self.boundConvert(True)
            return

        if self.bounds_crs is not None :
        
            other_to_mask = CoordTransformXY(self.bounds_crs, self.tile_mask_crs)
            
            topleft_x, topleft_y = other_to_mask.transform(topleft_x, topleft_y) 
            topleft_y, topleft_x = self.tile_mask_transformer.rowcol(topleft_x, topleft_y)
            
            bottomright_x, bottomright_y = other_to_mask.transform(bottomright_x, bottomright_y)  
            bottomright_y, bottomright_x = self.tile_mask_transformer.rowcol(bottomright_x, bottomright_y)
            
        topleft_y = max(0, int(topleft_y))
        topleft_x = max(0, int(topleft_x))
        bottomright_y = min(self.tile_mask_shape[0], int(bottomright_y))
        bottomright_x = min(self.tile_mask_shape[1], int(bottomright_x))

        if topleft_y >= bottomright_y or topleft_x >= bottomright_x :
            self.boundConvert(True)
            return
            
        self.tile_bounds = [topleft_y, topleft_x, bottomright_y, bottomright_x]
        self.invalid_bounds = False
        self.ui.bounds_err.setHidden(True)
        
        # Modify bounds frame
        
        bounds_geometry = QgsGeometry.fromPolygonXY([[QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[1])),
                                                      QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[3])),
                                                      QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[2], self.tile_bounds[3])),
                                                      QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[2], self.tile_bounds[1])),
                                                      QgsPointXY(*self.tile_mask_transformer.xy(self.tile_bounds[0], self.tile_bounds[1]))]])
        
        
        self.bounds_layer.committedGeometriesChanges.disconnect()
        self.bounds_layer.startEditing()                                   
        self.bounds_layer.changeGeometry(1, bounds_geometry)
        self.bounds_layer.commitChanges()
        self.bounds_layer.committedGeometriesChanges.connect(self.boundPolyEdit)

    def boundPolyEdit(self):
    
        """Bounds changed by modifying frame"""
    
        bounds_geometry = shapely.from_wkt(self.bounds_layer.getGeometry(1).asWkt()).exterior.coords.xy
        
        bounds_row, bounds_col = self.tile_mask_transformer.rowcol(np.array(bounds_geometry[0]), np.array(bounds_geometry[1]))
        
        tile_bounds = [int(np.ceil(np.amin(bounds_row))), int(np.ceil(np.amin(bounds_col))), int(np.ceil(np.amax(bounds_row))), int(np.ceil(np.amax(bounds_col)))]
        
        self.tile_bounds = tile_bounds
        
        self.boundConvert(True)
        
    def predefCRS(self):
    
        """Predefined button clicked, writing CRS WKT"""
    
        dialog = QgsProjectionSelectionDialog()
        dialog.exec()

        crs = dialog.crs()
        wkt = crs.toWkt()
        
        self.ui.crs_wkt.setText(wkt)
        
    def addBand(self):
    
        """Add band to Mask bands table"""
    
        self.ui.band_table.itemChanged.disconnect()
    
        band_num=self.ui.band_table.rowCount()
        band_names = [self.ui.band_table.item(row, 0).text() for row in range(0,band_num)]
        
        self.ui.band_table.insertRow(band_num)
        self.ui.band_table.setRowHeight(band_num,20) 
        
        band_index = 2
        while('mask'+str(band_index) in band_names):
            band_index += 1
            
        new_band_name = 'mask'+str(band_index)
        
        new_band_item=QTableWidgetItem(new_band_name)
        new_band_item.setFlags(new_band_item.flags() | Qt.ItemFlag.ItemIsEditable)
            
        self.ui.band_table.setItem(band_num, 0, new_band_item)
        band_names.append(new_band_name)
        
        self.ui.band_table.itemChanged.connect(self.editBand)
            
    def rmBand(self):
    
        """Remove band from Mask bands table"""
    
        if self.ui.band_table.rowCount()==1 :
            return
    
        self.ui.band_table.itemChanged.disconnect()
    
        selected_indexes=self.ui.band_table.selectedIndexes()
        selected_rows=np.unique(np.array([index.row() for index in selected_indexes],dtype=int))
        
        if len(selected_rows)==self.ui.band_table.rowCount() :
            selected_rows = selected_rows[1:]
    
        for row in selected_rows:
            self.ui.band_table.removeRow(row)
            
        self.ui.band_table.itemChanged.connect(self.editBand)
        
    def editBand(self):
    
        """Edit band names in Mask bands table"""

        band_num=self.ui.band_table.rowCount()
        band_names = [self.ui.band_table.item(row, 0).text() for row in range(0,band_num)]
        
    def saveBrowse(self, path_type):
    
        """Browse for the mask and tile list paths"""
    
        if path_type=='mask' :
            fname=QFileDialog.getSaveFileName(self, "Save file", os.path.join(self.browse_dir, 'mask.tif'), "TIF (*.tif *.tiff)")
            self.ui.mask_save.setText(fname[0])
            self.ui.mask_saveerr.setHidden(True)  
            
        elif path_type=='list' :
            fname=QFileDialog.getSaveFileName(self, "Save file", os.path.join(self.browse_dir, 'tiles.csv'), "CSV (*.csv)")
            self.ui.list_save.setText(fname[0])
            self.ui.list_saveerr.setHidden(True)   
        
        self.browse_dir = os.path.split(fname[0])[0]  
        
    def WHCheck(self, dim):
    
        """Check that the width and height inputs are numbers"""
    
        if dim=='width' :
            try:
                width = int(self.ui.tile_width.text())
            except:
                self.ui.tile_width.setText("224")
        elif dim=='height' :
            try:
                height = int(self.ui.tile_height.text())
            except:
                self.ui.tile_height.setText("224")
        
    def saveTiles(self):
    
        """Save tile list and mask"""
    
        if self.invalid_bounds :
            self.ui.bounds_err.setHidden(False)
            return
            
        # Check mask path
            
        if self.ui.mask_path_box.isChecked() :
    
            mask_path = self.ui.mask_save.text()
            mask_dir, mask_filename = os.path.split(mask_path)
                
            if not os.path.isdir(mask_dir) or mask_filename == "" or os.path.splitext(mask_filename)[1] not in ['.tif', '.tiff'] :
                self.ui.mask_saveerr.setHidden(False)
                return
                
        else:
            mask_path = self.ui.raster_choose.text()
            
        saved_list = False
        saved_mask = False
            
        # Save list
            
        if self.ui.list_path_box.isChecked() :
        
            list_path = self.ui.list_save.text()
            list_dir, list_filename = os.path.split(list_path)
                    
            if not os.path.isdir(list_dir) or list_filename == "" or os.path.splitext(list_filename)[1] != '.csv' :
                self.ui.list_saveerr.setHidden(False)
                return
                
            tile_height = int(self.ui.tile_height.text())
            tile_width = int(self.ui.tile_width.text())
            height_spacing = int((1-self.ui.height_overlap.value()/100)*tile_height)
            width_spacing = int((1-self.ui.width_overlap.value()/100)*tile_width)
            
            # Generate tile positions

            pos_y, pos_x = gridPositions(np.array([self.tile_bounds[0], self.tile_bounds[2]], dtype=int),
                                         np.array([self.tile_bounds[1], self.tile_bounds[3]], dtype=int),
                                         np.array([tile_height, tile_width], dtype=int),
                                         start = None,
                                         spacing = np.array([height_spacing, width_spacing], dtype=int)
                                         )
                                         
            pos_center_y = pos_y + tile_height/2
            pos_center_x = pos_x + tile_width/2
                                     
            # Retain only tile positions inside the bounds frame    
            
            bounds_geometry = shapely.from_wkt(self.bounds_layer.getGeometry(1).asWkt()).exterior.coords.xy
            bounds_y, bounds_x = self.tile_mask_transformer.rowcol(np.array(bounds_geometry[0]), np.array(bounds_geometry[1]))

            contained = shapely.contains_xy(shapely.Polygon(np.hstack([np.array(bounds_x)[:,np.newaxis], np.array(bounds_y)[:,np.newaxis]])), pos_center_x, pos_center_y)
                                         
            positions = pd.DataFrame({'y': pos_y[contained],
                                      'x': pos_x[contained]})
                                      
            positions['height'] = tile_height
            positions['width'] = tile_width
            positions['filename'] = mask_path
            positions['priority'] = 1
            
            positions.to_csv(list_path, index=False)
            
            saved_list = True
        
        # Save mask
        
        if self.ui.mask_path_box.isChecked() :

            band_num=self.ui.band_table.rowCount()        
            band_names = [self.ui.band_table.item(row, 0).text() for row in range(0,band_num)]
            
            band_dict = dict()
            band_values_dict = dict()
            
            # Default symbology
            
            for band_name in band_names:
            
                band_values_dict[band_name] = {0: ['NULL', '#ffffff', True],
                                               1: ['', '#ffffff', False]}
                                               
                band_dict[band_name] = np.zeros(self.tile_mask_shape, dtype=np.uint8)
                                               
            metadata = dict()
            metadata['qclassipy_values'] = str(band_values_dict)   
            
            # Generate mask GeoTIFF  

            generateTiff(mask_path, 
                         band_dict, 
                         self.tile_mask_transform, 
                         self.tile_mask_shape, 
                         self.tile_mask_crs, 
                         metadata = metadata)
            
            saved_mask = True
        
        # "Saved" message
        
        if saved_list or saved_mask :
            
            self.ui.saved_message.setHidden(False)
            
            self.saved_tmr = QTimer()
            self.saved_tmr.setSingleShot(True)
            self.saved_tmr.timeout.connect(lambda: self.ui.saved_message.setHidden(True))
            self.saved_tmr.start(1000)
                
    def closeEvent(self, event):
    
        """Close tab"""

        if self.bounds_layer is not None :
        
            self.bounds_layer.rollBack()
            self.bounds_layer.committedGeometriesChanges.disconnect()
            QgsProject.instance().removeMapLayer(self.bounds_layer.id())
            self.bounds_layer = None
        
        event.accept()
