import mathiasBynensEmojiRegex from 'emoji-regex';
import {
  fromCodepointToUnicode,
  fromHexcodeToCodepoint,
  fromUnicodeToHexcode,
} from 'emojibase';
import emojibaseEmojiRegex from 'emojibase-regex/emoji.js';
import SHORTCODE_REGEX from 'emojibase-regex/shortcode.js';
import { z } from 'zod';
import type { RenovateConfig } from '../config/types';
import dataFiles from '../data-files.generated';
import { logger } from '../logger';
import { regEx } from './regex';
import { Result } from './result';
import { Json } from './schema-utils';

let unicodeEmoji = true;

let mappingsInitialized = false;
const shortCodesByHex = new Map<string, string>();
const hexCodesByShort = new Map<string, string>();

const EmojiShortcodesSchema = Json.pipe(
  z.record(
    z.string(),
    z.union([z.string().transform((val) => [val]), z.array(z.string())]),
  ),
);
type EmojiShortcodeMapping = z.infer<typeof EmojiShortcodesSchema>;

const patchedEmojis: EmojiShortcodeMapping = {
  '26A0-FE0F': ['warning'], // Colorful warning (⚠️) instead of black and white (⚠)
};

function initMapping(mapping: EmojiShortcodeMapping): void {
  for (const [hex, shortcodes] of Object.entries(mapping)) {
    const mainShortcode = `:${shortcodes[0]}:`;

    shortCodesByHex.set(hex, mainShortcode);
    shortCodesByHex.set(stripHexCode(hex), mainShortcode);

    for (const shortcode of shortcodes) {
      hexCodesByShort.set(`:${shortcode}:`, hex);
    }
  }
}

function lazyInitMappings(): void {
  if (!mappingsInitialized) {
    const githubShortcodes = dataFiles.get(
      'node_modules/emojibase-data/en/shortcodes/github.json',
    );

    Result.parse(githubShortcodes, EmojiShortcodesSchema)
      .onValue((data) => {
        initMapping(data);
        initMapping(patchedEmojis);
        mappingsInitialized = true;
      })
      .onError(
        /* istanbul ignore next */
        (error) => {
          logger.warn({ error }, 'Unable to parse emoji shortcodes');
        },
      );
  }
}

export function setEmojiConfig(config: RenovateConfig): void {
  unicodeEmoji = !!config.unicodeEmoji;
}

const shortCodeRegex = regEx(SHORTCODE_REGEX.source, 'g');

export function emojify(text: string): string {
  if (!unicodeEmoji) {
    return text;
  }
  lazyInitMappings();
  return text.replace(shortCodeRegex, (shortCode) => {
    const hexCode = hexCodesByShort.get(shortCode);
    return hexCode
      ? fromCodepointToUnicode(fromHexcodeToCodepoint(hexCode))
      : shortCode;
  });
}

const emojiRegexSrc = [emojibaseEmojiRegex, mathiasBynensEmojiRegex()].map(
  ({ source }) => source,
);
const emojiRegex = new RegExp(`(?:${emojiRegexSrc.join('|')})`, 'g'); // TODO #12875 cannot figure it out
const excludedModifiers = new Set([
  '20E3',
  '200D',
  'FE0E',
  'FE0F',
  '1F3FB',
  '1F3FC',
  '1F3FD',
  '1F3FE',
  '1F3FF',
  '1F9B0',
  '1F9B1',
  '1F9B2',
  '1F9B3',
]);

export function stripHexCode(input: string): string {
  return input
    .split('-')
    .filter((modifier) => !excludedModifiers.has(modifier))
    .join('-');
}

export function unemojify(text: string): string {
  if (unicodeEmoji) {
    return text;
  }
  lazyInitMappings();
  return text.replace(emojiRegex, (emoji) => {
    const hexCode = stripHexCode(fromUnicodeToHexcode(emoji));
    const shortCode = shortCodesByHex.get(hexCode);
    return shortCode ?? /* istanbul ignore next */ '�';
  });
}

function stripEmoji(emoji: string): string {
  const hexCode = stripHexCode(fromUnicodeToHexcode(emoji));
  // `hexCode` could be empty if `emoji` is a modifier character that isn't
  // modifying anything
  if (hexCode) {
    const codePoint = fromHexcodeToCodepoint(hexCode);
    return fromCodepointToUnicode(codePoint);
  }
  return '';
}

export function stripEmojis(input: string): string {
  return input.replace(emojiRegex, stripEmoji);
}