import { useMemo } from 'react';
import { useClientConfig } from '../../hooks/useClientConfig';
import type { BotConfig, ClientConfig } from '../../hooks/useClientConfig';

export type BotPreset = {
  /** Stable URL slug — `/bots/<id>`. Never reuse across bots. */
  id: string;
  /** Bot user mxid. The DM with this user IS the bot's control room. */
  mxid: string;
  name: string;
};

const BOT_ID_RE = /^[A-Za-z0-9_-]+$/;
const MXID_RE = /^@[^:\s]+:[^\s]+$/;

const isValidBotPreset = (preset: BotConfig | undefined): preset is BotPreset =>
  typeof preset?.id === 'string' &&
  BOT_ID_RE.test(preset.id) &&
  typeof preset.mxid === 'string' &&
  MXID_RE.test(preset.mxid) &&
  typeof preset.name === 'string' &&
  preset.name.trim().length > 0;

export const getBotPresets = (clientConfig: ClientConfig): BotPreset[] => {
  const seenIds = new Set<string>();
  const seenMxids = new Set<string>();
  const bots: BotPreset[] = [];
  const configuredBots = Array.isArray(clientConfig.bots) ? clientConfig.bots : [];

  configuredBots.forEach((preset) => {
    if (!isValidBotPreset(preset)) return;
    if (seenIds.has(preset.id) || seenMxids.has(preset.mxid)) return;
    seenIds.add(preset.id);
    seenMxids.add(preset.mxid);
    bots.push({
      id: preset.id,
      mxid: preset.mxid,
      name: preset.name.trim(),
    });
  });

  return bots;
};

export const useBotPresets = (): BotPreset[] => {
  const clientConfig = useClientConfig();
  return useMemo(() => getBotPresets(clientConfig), [clientConfig]);
};

export const findBotPresetById = (
  presets: readonly BotPreset[],
  id: string
): BotPreset | undefined => presets.find((preset) => preset.id === id);