#!/usr/bin/env python
# -*- coding: utf-8 -*-
from yaml import safe_load
from typing import Iterable
from pathlib import Path
import logging

path_stickers_root = Path('.')
path_stickers_output_dir = path_stickers_root / 'stickers'
path_stickers_output_dir.mkdir(exist_ok=True)
path_stickers_source_dir = path_stickers_root / 'src'
path_stickers_data_dir = path_stickers_root / 'data'
logging.basicConfig(
    filename=str(path_stickers_root / 'make.log'),
    level=logging.DEBUG)
log = logging.getLogger('stickers.actions')
log.setLevel(logging.DEBUG)
log.debug('path_stickers_root = %s', path_stickers_root)
log.debug('path_stickers_data_dir = %s', path_stickers_data_dir)


class StickerTasks:
    defs: Iterable
    dst_width: int
    dst_height: int
    dst_format: str
    ffmpeg_opts: list[str]

    def __init__(self,
                 defs_src: Iterable | None = None,
                 dst_width: int = 512,
                 dst_height: int = 512,
                 dst_format: str = 'png',
                 dst_ext: str = 'png',
                 ffmpeg_opts: list[str] = list()):
        if defs_src is None:
            defs_src = path_stickers_data_dir.glob("*.yaml")
        self._log = log.getChild(self.__class__.__name__)
        self.defs = defs_src
        self.dst_height = dst_height
        self.dst_width = dst_width
        self.dst_format = dst_format
        self.dst_ext = dst_ext
        self.ffmpeg_opts = ffmpeg_opts

    def create_doit_tasks(self=None):
        log = self._log
        if self is None:
            log.debug('method called as class method, silently returning')
            return
        log.info('creating %s stickers with %s dimensions and %s opts',
                 self.dst_format, f"{self.dst_width}x{self.dst_height}",
                 self.ffmpeg_opts)
        for def_filepath in self.defs:
            log.debug("def file: %s", def_filepath)
            with open(def_filepath) as stream:
                sticker_info = safe_load(stream)
            if sticker_info.get("disabled", False):
                log.info("file %s is disabled, skipping", def_filepath)
                continue
            yield self.create_doit_sticker_task(sticker_info, def_filepath)

    def create_doit_sticker_task(self, sticker_info, def_filepath):
        # Handling logging
        sticker_log = self._log.getChild(sticker_info['name'])
        out_filename = f'{sticker_info["name"]}.{self.dst_ext}'
        target_filename = path_stickers_output_dir / out_filename
        sticker_log.debug('target filename: %s', target_filename)
        # Handling dependencies
        file_dep = [def_filepath]
        try:
            if (
                sticker_info['input']['base'].get('format', '')
                not in ('lavfi', 'image2')
            ):
                base_input = path_stickers_source_dir / \
                    sticker_info["input"]["base"]["input"]
                file_dep.append(base_input)
                sticker_log.debug("file_dep updated: %s", base_input)
        except KeyError:
            sticker_log.info("sticker does not have base file input")
            base_input = None
        # Handling ffmpeg invocation argument array
        ffmpeg_argv = ['ffmpeg']
        # ffmpeg: input format
        if sticker_info['input']['base'].get('format'):
            ffmpeg_argv += ['-f', sticker_info['input']['base']['format']]
        # ffmpeg: input frame rate
        if sticker_info['input']['base'].get('framerate'):
            ffmpeg_argv += ['-framerate',
                            sticker_info['input']['base']['framerate']]
        # ffmpeg: input file itself
        ffmpeg_argv += ['-i', base_input]
        # ffmpeg: video filter
        ffmpeg_argv.append('-vf')
        filterspec = ''
        if sticker_info['input'].get('colors', {}).get('transparent'):
            transparent = sticker_info['input']['colors']['transparent']
            filterspec += 'geq=\''
            filterspec += f'r=if(lt(alpha(X,Y),128),{transparent[0]},r(X,Y)):'
            filterspec += f'g=if(lt(alpha(X,Y),128),{transparent[1]},g(X,Y)):'
            filterspec += f'b=if(lt(alpha(X,Y),128),{transparent[2]},b(X,Y)):'
            filterspec += 'a=alpha(X,Y)\','

        filterspec += f'scale=w={self.dst_width}:h={
            self.dst_height}:force_original_aspect_ratio=decrease'
        if sticker_info.get('output', {}).get('speed'):
            filterspec += f',setpts={
                sticker_info['output']['speed']}'
        ffmpeg_argv.append(filterspec)
        ffmpeg_argv.append('-y')
        # ffmpeg: extra arguments
        ffmpeg_argv += self.ffmpeg_opts
        # ffmpeg: specify outut
        ffmpeg_argv.append(target_filename)
        sticker_log.debug('ffmpeg argv: %s', ffmpeg_argv)
        ret = {
            'actions': [ffmpeg_argv],
            'name': out_filename,
            'targets': [target_filename],
            'file_dep': file_dep
        }
        sticker_log.debug('task spec: %s', ret)
        return ret


png = StickerTasks(ffmpeg_opts=['-preset:v', 'icon', '-frames:v', '1'])
webm = StickerTasks(
    dst_format='webm',
    dst_ext='webm',
    ffmpeg_opts=['-codec:v', 'libvpx-vp9', '-map', 'v', '-pix_fmt', 'yuva420p']
)
webp = StickerTasks(
    dst_format='webp',
    dst_ext='webp',
    ffmpeg_opts=['-lossless', '1', '-frames:v', '1']
)

emoji_webp = StickerTasks(
    dst_format='webp',
    dst_ext='emoji.webp',
    ffmpeg_opts=['-lossless', '1', '-frames:v', '1'],
    dst_height=100,
    dst_width=100
)