#!/usr/bin/env python3
from enum import IntEnum
from copy import deepcopy
from PIL import Image
import os

class DotTile(IntEnum):
    NDT = 0 # no dot
    SPD = 1 # small pac-dot
    BPD = 2 # big pac-dot
    FRT = 3 # fruit

class PhysTile(IntEnum):
    GRD = 0 # ground
    WAL = 1 # wall
    GSD = 2 # ghost door
    GWL = 3 # ghost cell wall
    GCF = 4 # ghost cell floor
    TPT = 5 # teleporter tile
    FIT = 6 # fully inaccessible tile
    # ghost-cell ground as FIT ? verify no pac-dot here

class Map:
    """
    Pacman maps size is 28×31
    """

    width = 28 * 2 + 1
    height = 31 * 2 + 1
    # tile_size = 16 # tile subdivision for dynamic movement

    def __init__(self, phys_map = [], dots_map = [], maze_img_file=""):
        """
        physic_map is the array containing elements:
        0: ground tile
        1: wall
        2: ghost door
        3: teleporter (no need to precise which to go because we assume it will
           be at the opposite map tile)
        4: fully inaccessible tile (basically tiles that represent the "in-wall"
           space)

        dots_map is a layer on top of the physic_map of the same dimension which contains
        0: no dot
        1: small pac-dot
        2: big pac-dot
        """
        if maze_img_file and os.path.isfile(maze_img_file):
            print('coucou')
            try:
                self.phys_map = decode_map(maze_img_file)
            except Exception as e:
                raise e
        else:
            self.phys_map = phys_map # in the first part we assume phys_map is correct and no need to verify
            self.dots_map = dots_map
        self.intersect_map = [] # TODO - the layer which contains intersections pre-calculated


    def verify(self, phys_map, dots_map) -> bool:
        """
        This method will verify if a given map is valid or not
        Return True if correct else False

        we will assume
        there are only:
        - 1 ghost door
        - 4 big pac-dots
        - 240 pac-dots

        Each ground tile must have at least 2 ground tile neighboors because
        there is no dead-end tile in pac-man
        Each dot must be on a ground tile (not even a teleporter one)
        """

        if not (len(phys_map) == len(dots_map) == 31):
            return False
        
        for i in range(len(phys_map)):
            if not (len(phys_map[i]) == len(dots_map[i]) == 28):
                return False

        # 1 ghost door verification
        if sum(sub_arr.count(PhysTile.GSD) for sub_arr in phys_map) != 1:
            return False

        # # 4 big pac dots
        if sum(sub_arr.count(DotTile.BPD) for sub_arr in dots_map) != 4:
            return False

        # # 240 small pac-dots
        if sum(sub_arr.count(DotTile.SPD) for sub_arr in dots_map) != 240:
            return False

        # dots are only in ground tile
        for row in range(len(phys_map)):
            for col in range(len(phys_map[0])):
                if dots_map[row][col] and phys_map[row][col]: # no dot = 0; ground = 0
                    return False

        # odd number of teleporter tiles
        teleporter_count = sum(sub_arr.count(PhysTile.TPT) for sub_arr in phys_map)
        if teleporter_count % 2:
            return False

        edges = phys_map[0][1:] + phys_map[-1][1:] + [sub[0] for sub in phys_map] \
                + [sub[-1] for sub in phys_map][1:-1]
        
        # no ground tile on edges
        if PhysTile.GRD in edges:
            return False

        # teleporters are in front of the other
        for col in range(1, len(phys_map[0])-1):
            if phys_map[0][col] == PhysTile.TPT or phys_map[-1][col] == PhysTile.TPT:
                if phys_map[0][col] == phys_map[-1][col]:
                    teleporter_count -= 2
                else:
                    return False
        for row in range(1, len(phys_map)-1):
            if phys_map[row][0] == PhysTile.TPT or phys_map[row][-1] == PhysTile.TPT:
                if phys_map[row][0] == phys_map[row][-1]:
                    teleporter_count -= 2
                else:
                    return False

        if teleporter_count: # not all teleporters are on edges
            return False

        # no teleporter on corners
        if any(PhysTile.TPT in (phys_map[0][0], phys_map[0][-1],
               phys_map[self.height-1][0], phys_map[-1][-1])):
            return False

        # now we have to verify there is no dead-end ground tile
        for col in range(1, self.width-1):
            for row in range(1, self.height-1):
                cpt = 0
                for x, y in ((0, 1), (1, 0), (-1, 0), (0, -1)):
                    if phys_map[row+y][col+x] in (PhysTile.GRD, PhysTile.TPT):
                        cpt += 1
                        if cpt == 2:
                            break
                if cpt < 2:
                    return False
        # we have to verify if there is only 1 connexity component of (PhysTile.GRD, PhysTile.TPT, PhysTile.BPD, PhysTile.SPD)
        if not connex(phys_map):
            return False

        return True

    def get_tile(self, x, y):
        return self.phys_map[y][x]

def explore(matrix, x=-1, y=-1):
    """explore the given matrix and change it (GRD and TPT become FIT)"""
    if x < 0 and y < 0:
        # searching the beginning
        for row in range(len(matrix)):
            for col in range(len(matrix[0])):
                if matrix[row][col]:
                    explore(matrix, col, row)
    elif matrix[y][x] in (PhysTile.TPT, PhysTile.GRD):
        matrix[y][x] = PhysTile.FIT
        for col, row in ((0, 1), (1, 0), (0, -1), (-1, 0)):
            explore(matrix, (x+col)%len(matrix[0]), (y+row)%len(matrix))


def connex(matrix, x=-1, y=-1):
    """return True if the matrix is connex - has only one connexity part"""
    temp = deepcopy(matrix)
    explore(temp)
    if any(tile in (PhysTile.GRD, PhysTile.TPT) for row in temp for tile in row):
        return False
    return True    

def decode_map(img_file):
    img = Image.open(img_file)
    dictionnary = {
        (0  ,   0,   0): PhysTile.GRD,
        (255,   0, 255): PhysTile.GCF,
        (0  ,   0, 255): PhysTile.WAL,
        (0  , 255,   0): PhysTile.GSD,
        (0  , 255, 255): PhysTile.GWL,
        (255,   0,   0): PhysTile.TPT,
        (255, 255,   0): PhysTile.FIT,
    }
    data = list(img.getdata())
    matrix = []
    for row in range(img.height):
        matrix.append([])
        for col in range(img.width):
            try:
                tile = dictionnary[data[col + row*img.width][:3]] # avoid alpha component
            except:
                raise ValueError("Pixel " + str(col) + "," + str(row) + " is invalid")
            matrix[-1].append(tile)
    return matrix