import { searchCalendar } from './adapters/calendar.mjs';
import { searchChat } from './adapters/chat.mjs';
import { searchMeinput } from './adapters/meinput.mjs';
import { buildContextPlan } from './context-planner.mjs';
import { dedupeTimelineItems } from './dedupe.mjs';
import { rankTimelineItems } from './rank.mjs';

const SOURCE_HANDLERS = {
  calendar: searchCalendar,
  meinput: searchMeinput,
  chat: searchChat,
};

/**
 * @param {import('mysql2/promise').Pool | null} pool
 * @param {{ plan: object, userId: string, sessionId?: string, limit?: number }} opts
 */
export async function executeTemporalRecall(pool, opts) {
  const started = Date.now();
  const plan = opts.plan;
  const userId = opts.userId;
  const limit = Math.min(200, Math.max(1, Number(opts.limit ?? plan.output?.max_items ?? 50)));
  const skipBelow = 0.3;

  const sourcesQueried = [];
  const tasks = (plan.retrievals ?? [])
    .filter((r) => (r.weight ?? 0) >= (r.skip_below ?? skipBelow))
    .map(async (retrieval) => {
      const handler = SOURCE_HANDLERS[retrieval.source];
      if (!handler) return [];
      sourcesQueried.push(retrieval.source);
      const ctx = {
        userId,
        pool,
        retrieval,
        time: plan.time,
        temporalMode: plan.temporal_mode,
        sessionId: opts.sessionId,
      };
      if (retrieval.source === 'chat') return searchChat(pool, ctx);
      return handler(ctx);
    });

  const batches = await Promise.all(tasks);
  const raw = batches.flat();
  const ranked = rankTimelineItems(raw, plan);
  const deduped = plan.output?.dedupe !== false ? dedupeTimelineItems(ranked) : ranked;
  const returned = deduped.slice(0, limit);

  let groups = null;
  if (plan.temporal_mode === 'AMBIGUOUS' && plan.output?.timeline) {
    const mentionStart = new Date(plan.time.mention_range.start).getTime();
    const mentionEnd = new Date(plan.time.mention_range.end).getTime();
    const occurred = [];
    const mentioned = [];
    for (const item of returned) {
      const obs = new Date(item.observed_time).getTime();
      if (item.event_time) {
        const ev = new Date(item.event_time).getTime();
        if (ev >= mentionStart && ev < mentionEnd) occurred.push(item);
        else mentioned.push(item);
      } else if (obs >= mentionStart && obs < mentionEnd) {
        mentioned.push(item);
      } else {
        occurred.push(item);
      }
    }
    groups = [
      { label: 'occurred_in_range', items: occurred },
      { label: 'mentioned_or_planned', items: mentioned },
    ];
  }

  return {
    query_type: plan.query_type,
    temporal_mode: plan.temporal_mode,
    time_range: plan.time.mention_range,
    groups,
    items: groups ? [] : returned,
    stats: {
      sources_queried: sourcesQueried,
      raw_count: raw.length,
      deduped_count: deduped.length,
      returned_count: returned.length,
      elapsed_ms: Date.now() - started,
    },
    plan,
  };
}

/**
 * @param {import('mysql2/promise').Pool | null} pool
 * @param {{ query?: string, plan?: object, user_id: string, now?: Date, session_id?: string, limit?: number }} input
 */
export async function queryTemporalRecall(pool, input) {
  const userId = input.user_id;
  const plan =
    input.plan ??
    buildContextPlan({
      query: input.query ?? '',
      user_id: userId,
      now: input.now,
    });

  if (plan.context_needs?.temporal_recall === 'SKIP') {
    return {
      query_type: plan.query_type,
      temporal_mode: plan.temporal_mode,
      time_range: plan.time?.mention_range ?? null,
      groups: null,
      items: [],
      stats: { sources_queried: [], raw_count: 0, deduped_count: 0, returned_count: 0, elapsed_ms: 0 },
      plan,
    };
  }

  return executeTemporalRecall(pool, {
    plan,
    userId,
    sessionId: input.session_id,
    limit: input.limit,
  });
}

export { buildContextPlan };