import asyncio
import json
import logging
import pathlib
import random
import shutil
from io import BytesIO
from typing import List, Union, Optional

import numpy
from PIL import Image, ImageChops, ImageColor, ImageDraw, ImageFont, ImageOps
from PIL.ImageDraw import _color_diff
from redbot.core.utils import AsyncIter

log = logging.getLogger("red.fox_v3.conquest.regioner")


MAP_FONT: Optional[ImageFont.ImageFont] = None
MASK_MODE = "1"  # "L" for 8 bit masks, "1" for 1 bit masks


async def composite_regions(im, regions, color, masks_path) -> Union[Image.Image, None]:
    im2 = Image.new("RGB", im.size, color)

    loop = asyncio.get_running_loop()

    combined_mask = None
    for region in regions:
        mask = Image.open(masks_path / f"{region}.png").convert(MASK_MODE)
        if combined_mask is None:
            combined_mask = mask
        else:
            # combined_mask = ImageChops.logical_or(combined_mask, mask)
            combined_mask = await loop.run_in_executor(
                None, ImageChops.logical_and, combined_mask, mask
            )

    if combined_mask is None:  # No regions usually
        return None

    out = await loop.run_in_executor(None, Image.composite, im, im2, combined_mask)

    return out


def get_center(points):
    """
    Taken from https://stackoverflow.com/questions/4355894/how-to-get-center-of-set-of-points-using-python
    """
    x = [p[0] for p in points]
    y = [p[1] for p in points]
    return sum(x) / len(points), sum(y) / len(points)


def recommended_combinations(mask_centers):
    pass  # TODO: Create recommendation algo and test it


def chunker(seq, size):
    """https://stackoverflow.com/a/434328"""
    return (seq[pos:pos + size] for pos in range(0, len(seq), size))


def floodfill(image, xy, value, border=None, thresh=0) -> set:
    """
    Taken and modified from PIL.ImageDraw.floodfill

    (experimental) Fills a bounded region with a given color.

    :param image: Target image.
    :param xy: Seed position (a 2-item coordinate tuple). See
        :ref:`coordinate-system`.
    :param value: Fill color.
    :param border: Optional border value.  If given, the region consists of
        pixels with a color different from the border color.  If not given,
        the region consists of pixels having the same color as the seed
        pixel.
    :param thresh: Optional threshold value which specifies a maximum
        tolerable difference of a pixel value from the 'background' in
        order for it to be replaced. Useful for filling regions of
        non-homogeneous, but similar, colors.
    """
    # based on an implementation by Eric S. Raymond
    # amended by yo1995 @20180806
    pixel = image.load()
    x, y = xy
    try:
        background = pixel[x, y]
        if _color_diff(value, background) <= thresh:
            return set()  # seed point already has fill color
        pixel[x, y] = value
    except (ValueError, IndexError):
        return set()  # seed point outside image
    edge = {(x, y)}
    # use a set to keep record of current and previous edge pixels
    # to reduce memory consumption
    filled_pixels = set()
    full_edge = set()
    while edge:
        filled_pixels.update(edge)
        new_edge = set()
        for (x, y) in edge:  # 4 adjacent method
            for (s, t) in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
                # If already processed, or if a coordinate is negative, skip
                if (s, t) in full_edge or s < 0 or t < 0:
                    continue
                try:
                    p = pixel[s, t]
                except (ValueError, IndexError):
                    pass
                else:
                    full_edge.add((s, t))
                    if border is None:
                        fill = _color_diff(p, background) <= thresh
                    else:
                        fill = p not in [value, border]
                    if fill:
                        pixel[s, t] = value
                        new_edge.add((s, t))
        full_edge = edge  # discard pixels processed
        edge = new_edge
    return filled_pixels  # Modified to returned the filled pixels


def create_number_mask(regions, filepath, filename):
    base_img_path = filepath / filename
    if not base_img_path.exists():
        return False

    base_img: Image.Image = Image.open(base_img_path)

    number_img = Image.new("L", base_img.size, 255)
    background_img = Image.new("L", base_img.size, 255)
    number2_img = Image.new("L", base_img.size, 255)
    if MAP_FONT is None:
        fnt = ImageFont.load_default()
    else:
        fnt = MAP_FONT
    d = ImageDraw.Draw(number_img)
    d2 = ImageDraw.Draw(background_img)
    d3 = ImageDraw.Draw(number2_img)
    for region_num, region in regions.items():
        text = getattr(region, "name", str(region_num))

        w1, h1 = region.center
        w2, h2 = fnt.getsize(text)

        d2.rectangle(
            (w1 - (w2 / 2) - 1, h1 - (h2 / 2) + 5, w1 + (w2 / 2) - 1, h1 + (h2 / 2)), fill=0
        )
        d3.rectangle(
            (w1 - (w2 / 2) - 1, h1 - (h2 / 2) + 5, w1 + (w2 / 2) - 1, h1 + (h2 / 2)), fill=0
        )
        d3.text((w1 - (w2 / 2), h1 - (h2 / 2)), text, font=fnt, fill=255)
        d.text((w1 - (w2 / 2), h1 - (h2 / 2)), text, font=fnt, fill=0)
    number_img.save(filepath / "numbers.png", "PNG")
    background_img.save(filepath / "numbers_background.png", "PNG")
    number2_img.save(filepath / "numbers2.png", "PNG")
    return True


class ConquestMap:
    def __init__(self, path: pathlib.Path):
        self.path = path

        self.name = None
        self.custom = None
        self.region_max = None
        self.regions = {}

    def masks_path(self):
        return self.path / "masks"

    def data_path(self):
        return self.path / "data.json"

    def blank_path(self):
        return self.path / "blank.png"  # Everything is png now

    def numbers_path(self):
        return self.path / "numbers.png"

    def numbered_path(self):
        return self.path / "numbered.png"

    def numbers_background_path(self):
        return self.path / "numbers_background.png"

    def numbers2_path(self):
        return self.path / "numbers2.png"

    def load_data(self):
        with self.data_path().open() as dp:
            data = json.load(dp)

        self.name = data.get("name")
        self.custom = data.get("custom")
        self.region_max = data.get("region_max")
        if "regions" in data:
            self.regions = {int(key): Region(**data) for key, data in data["regions"].items()}
        else:
            self.regions = {}

    async def create_number_mask(self):
        loop = asyncio.get_running_loop()
        return await loop.run_in_executor(
            None, create_number_mask, self.regions, self.path, "blank.png"
        )

    def _img_combine_masks(self, mask_list: List[int]):
        if not mask_list or len(mask_list) < 2:
            return False, None, None

        if not self.blank_path().exists():
            return False, None, None

        if not self.masks_path().exists():
            return False, None, None

        base_img: Image.Image = Image.open(self.blank_path())
        mask = Image.new(MASK_MODE, base_img.size, 1)

        lowest_num = None
        eliminated_masks = []

        for mask_num in mask_list:
            if lowest_num is None:
                lowest_num = mask_num
            elif mask_num < lowest_num:
                eliminated_masks.append(lowest_num)
                lowest_num = mask_num
            else:
                eliminated_masks.append(mask_num)

            mask2 = Image.open(self.masks_path() / f"{mask_num}.png").convert(MASK_MODE)
            mask = ImageChops.logical_and(mask, mask2)

        return lowest_num, eliminated_masks, mask

    async def sample_region(self, region: int, include_numbered=False):
        if region not in self.regions:
            return []

        files = []

        current_map = Image.open(self.blank_path())
        current_map = await composite_regions(
            current_map, [region], ImageColor.getrgb("red"), self.masks_path()
        )

        buffer1 = BytesIO()
        current_map.save(buffer1, "png")
        buffer1.seek(0)
        files.append(buffer1)

        if include_numbered:
            current_numbered_img = await self.get_numbered(current_map)
            buffer2 = BytesIO()
            current_numbered_img.save(buffer2, "png")
            buffer2.seek(0)
            files.append(buffer2)

        return files

    async def get_sample(self, region=None):
        files = [self.blank_path()]

        masks_dir = self.masks_path()
        if masks_dir.exists() and masks_dir.is_dir():
            current_map = Image.open(self.blank_path())

            if region is not None:
                if region in self.regions:
                    current_map = await composite_regions(
                        current_map, [region], ImageColor.getrgb("red"), self.masks_path()
                    )
            else:
                regions = list(self.regions.keys())

                random.shuffle(regions)  # random lets goo

                fourth = len(regions) // 4

                current_map = await composite_regions(
                    current_map, regions[:fourth], ImageColor.getrgb("red"), self.masks_path()
                )
                current_map = await composite_regions(
                    current_map,
                    regions[fourth : fourth * 2],
                    ImageColor.getrgb("green"),
                    self.masks_path(),
                )
                current_map = await composite_regions(
                    current_map,
                    regions[fourth * 2 : fourth * 3],
                    ImageColor.getrgb("blue"),
                    self.masks_path(),
                )
                current_map = await composite_regions(
                    current_map,
                    regions[fourth * 3 :],
                    ImageColor.getrgb("yellow"),
                    self.masks_path(),
                )

            current_numbered_img = await self.get_numbered(current_map)

            buffer1 = BytesIO()
            buffer2 = BytesIO()

            current_map.save(buffer1, "png")
            buffer1.seek(0)
            current_numbered_img.save(buffer2, "png")
            buffer2.seek(0)

            files.append(buffer1)
            files.append(buffer2)

        return files

    async def get_blank_numbered_file(self):
        im = await self.get_numbered(Image.open(self.blank_path()))
        buffer1 = BytesIO()

        im.save(buffer1, "png")
        buffer1.seek(0)
        return buffer1

    async def get_numbered(self, current_map):
        # return await self.get_inverted_numbered(current_map)

        return await self.get_numbered_with_background(current_map)

    async def get_inverted_numbered(self, current_map):
        loop = asyncio.get_running_loop()
        numbers = Image.open(self.numbers_path()).convert("L")
        inverted_map = ImageOps.invert(current_map)
        current_numbered_img = await loop.run_in_executor(
            None, Image.composite, current_map, inverted_map, numbers
        )
        return current_numbered_img

    async def get_numbered_with_background(self, current_map):
        loop = asyncio.get_running_loop()
        current_map = current_map.convert("RGBA")
        # numbers = Image.open(self.numbers_path()).convert("L")
        numbers_mask = Image.open(self.numbers_background_path()).convert("L")
        numbers_background = Image.open(self.numbers2_path()).convert("RGB")
        # inverted_map = ImageOps.invert(current_map)
        # current_numbered_img = await loop.run_in_executor(
        #     None, Image.composite, current_map, inverted_map, numbers
        # )

        current_numbered_img = await loop.run_in_executor(
            None, Image.composite, current_map, numbers_background, numbers_mask
        )

        return current_numbered_img


class MapMaker(ConquestMap):
    async def change_name(self, new_name: str, new_path: pathlib.Path):
        if new_path.exists() and new_path.is_dir():
            # This is an overwrite operation
            # await ctx.maybe_send_embed(f"{map_name} already exists, okay to overwrite?")
            #
            # pred = MessagePredicate.yes_or_no(ctx)
            # try:
            #     await self.bot.wait_for("message", check=pred, timeout=30)
            # except TimeoutError:
            #     await ctx.maybe_send_embed("Response timed out, cancelling save")
            #     return
            # if not pred.result:
            #     return
            return False, "Overwrite currently not supported"

        # This is a new name
        new_path.mkdir()

        shutil.copytree(self.path, new_path)

        self.custom = True  # If this wasn't a custom map, it is now

        self.name = new_name
        self.path = new_path

        await self.save_data()

        return True

    async def generate_masks(self):
        regioner = Regioner(filename="blank.png", filepath=self.path)
        loop = asyncio.get_running_loop()
        regions = await loop.run_in_executor(None, regioner.execute)

        if not regions:
            return regions

        self.regions = regions
        self.region_max = len(regions) + 1

        await self.save_data()
        return regions

    async def combine_masks(self, mask_list: List[int]):
        loop = asyncio.get_running_loop()
        lowest, eliminated, mask = await loop.run_in_executor(
            None, self._img_combine_masks, mask_list
        )

        if not lowest:
            return lowest

        try:
            elim_regions = [self.regions[n] for n in eliminated]
            lowest_region = self.regions[lowest]
        except KeyError:
            return False

        mask.save(self.masks_path() / f"{lowest}.png", "PNG")

        # points = [self.mm["regions"][f"{n}"]["center"] for n in mask_list]
        #
        # points = [(r.center, r.weight) for r in elim_regions]

        weighted_points = [r.center for r in elim_regions for _ in range(r.weight)] + [
            lowest_region.center for _ in range(lowest_region.weight)
        ]

        lowest_region.center = get_center(weighted_points)
        lowest_region.weight += sum(r.weight for r in elim_regions)

        for key in eliminated:
            self.regions.pop(key)
            # self.mm["regions"].pop(f"{key}")

        if self.region_max in eliminated:  # Max region has changed
            self.region_max = max(self.regions.keys())

        await self.create_number_mask()

        await self.save_data()

        return lowest

    async def delete_masks(self, mask_list):
        try:
            for key in mask_list:
                self.regions.pop(key)
                # self.mm["regions"].pop(f"{key}")
        except KeyError:
            return False

        if self.region_max in mask_list:  # Max region has changed
            self.region_max = max(self.regions.keys())

        await self.create_number_mask()

        await self.save_data()

        return mask_list

    async def save_data(self):
        to_save = {
            "name": self.name,
            "custom": self.custom,
            "region_max": self.region_max,
            "regions": {num: r.get_json() for num, r in self.regions.items()},
        }
        with self.data_path().open("w+") as dp:
            json.dump(to_save, dp, sort_keys=True, indent=4)

    async def init_directory(self, name: str, path: pathlib.Path, image: Image.Image):
        if not path.exists() or not path.is_dir():
            path.mkdir()

        self.name = name
        self.path = path

        await self.save_data()

        image.save(self.blank_path(), "PNG")

        return True

    async def recalculate_region(self, regions=None):
        # TODO: Refactor
        if regions is None:
            async for num, r in AsyncIter(self.regions.items()):

                points = await self.get_points_from_mask(num)

                r.center = get_center(points)
                r.weight = len(points)
        else:
            async for region in AsyncIter(regions):
                num = region
                r = self.regions[num]

                points = await self.get_points_from_mask(region)

                r.center = get_center(points)
                r.weight = len(points)

        await self.save_data()

    async def sort_regions(self, fast_sort=True):
        if fast_sort:  # Topmost, then leftmost
            regions = []

            async for num in AsyncIter(self.regions.keys()):
                points = await self.get_points_from_mask(num)

                points = list(points)
                points.sort(key=lambda x: x[1])
                regions.append((points[0], num))

            regions.sort(key=lambda x: x[0][1])

        else:  # Chunked approach from Regioner.execute (test that first)
            raise NotImplementedError

        # Rename all masks to mask_old
        async for num in AsyncIter(self.regions.keys()):
            old_mask = self.masks_path() / f"{num}.png"
            new_mask = self.masks_path() / f"{num}_old.png"

            old_mask.rename(new_mask)

        # Rename all _old masks to their new num, and make the new dictionary of data
        new_regions = {}
        async for new_num, old_num in AsyncIter(enumerate((r[1] for r in regions), start=1)):
            old_mask = self.masks_path() / f"{old_num}_old.png"
            new_mask = self.masks_path() / f"{new_num}.png"

            old_mask.rename(new_mask)

            new_regions[new_num] = self.regions[old_num]

        # Save the new dictionary to regions
        self.regions = new_regions
        await self.save_data()

    async def get_points_from_mask(self, region):
        mask: Image.Image = Image.open(self.masks_path() / f"{region}.png").convert(MASK_MODE)
        arr = numpy.array(mask)
        found = numpy.where(arr == 0)
        points = set(list(zip(found[1], found[0])))  # x then y I think?
        return points

    async def convert_masks(self, regions):
        if regions:
            async for region in regions:
                mask_path = self.masks_path() / f"{region}.png"
                img: Image.Image = Image.open(mask_path).convert(MASK_MODE)
                img.save(mask_path)
        else:
            async for mask_path in AsyncIter(self.masks_path().iterdir()):
                # Don't both checking if masks are in self.regions
                img: Image.Image = Image.open(mask_path).convert(MASK_MODE)
                img.save(mask_path, "PNG")
        return True

    async def prune_masks(self):
        """Two step process:

        1. Delete all mask images that aren't in self.regions
        2. Iterate through regions numerically, renaming all mask images to that number
            All so 1 3 4 doesn't cause 4->3 to overwrite 3->2"""

        pruned = []
        # Step 1
        async for mask in AsyncIter(self.masks_path().iterdir(), steps=5):
            if int(mask.stem) not in self.regions:
                mask.unlink()
                pruned.append(mask.stem)

        # Step 2
        new_regions = {}
        async for newnum, (num, data) in AsyncIter(
            enumerate(self.regions.items(), start=1), steps=5
        ):
            new_regions[newnum] = data

            if newnum == num:
                continue

            old_mask = self.masks_path() / f"{num}.png"
            new_mask = self.masks_path() / f"{newnum}.png"

            old_mask.rename(new_mask)

        self.regions = new_regions
        self.region_max = max(self.regions.keys())  # I could use len() here, but max to be safe

        await self.save_data()

        return pruned


class Region:
    def __init__(self, center, weight, **kwargs):
        self.center = center
        self.weight = weight
        self.data = kwargs

    def get_json(self):
        return {"center": self.center, "weight": self.weight, **self.data}


class Regioner:
    def __init__(
        self, filepath: pathlib.Path, filename: str, region_color=None, wall_color="black"
    ):
        self.filepath = filepath
        self.filename = filename
        self.wall_color = ImageColor.getcolor(wall_color, "L")
        if region_color is None:
            self.region_color = None
        else:
            self.region_color = ImageColor.getcolor(region_color, "L")

    def execute(self):
        """
        Create the regions of the map

        TODO: Using proper multithreading best practices.
        TODO: This is iterating over a 2d array with some overlap, you went to school for this Bozo

        TODO: Fails on some maps where borders aren't just black (i.e. water borders vs region borders)
        """

        base_img_path = self.filepath / self.filename
        if not base_img_path.exists():
            return False

        masks_path = self.filepath / "masks"

        if not masks_path.exists():
            masks_path.mkdir()

        black = ImageColor.getcolor("black", "L")
        white = ImageColor.getcolor("white", "L")

        base_img: Image.Image = Image.open(base_img_path).convert("L")
        already_processed = set()

        mask_count = 0
        regions = {}

        for y_chunk in chunker(range(base_img.height), base_img.height // 10):
            for y1 in y_chunk:
                for x_chunk in chunker(range(base_img.width), base_img.width // 10):
                    for x1 in x_chunk:
                        if (x1, y1) in already_processed:
                            continue
                        if (
                            self.region_color is None and base_img.getpixel((x1, y1)) != self.wall_color
                        ) or base_img.getpixel((x1, y1)) == self.region_color:
                            filled = floodfill(base_img, (x1, y1), self.wall_color, self.wall_color)
                            if filled:  # Pixels were updated, make them into a mask
                                mask = Image.new(MASK_MODE, base_img.size, 255)
                                for x2, y2 in filled:
                                    mask.putpixel((x2, y2), 0)  # TODO: Switch to ImageDraw

                                mask_count += 1
                                # mask = mask.convert(MASK_MODE)  # I don't think this does anything
                                mask.save(masks_path / f"{mask_count}.png", "PNG")

                                regions[mask_count] = Region(center=get_center(filled), weight=len(filled))

                                already_processed.update(filled)

        create_number_mask(regions, self.filepath, self.filename)
        return regions