// Unified memory query — one surface that takes any input, normalizes
// it, and returns every memory signal the system has: playbook workers,
// KB pathway recommendations, prior lessons, staffer competence stats,
// and cross-staffer discovered patterns. This is the "seamlessly with
// whatever input" answer J framed it as.
//
// Why a unified gateway instead of separate calls: the memory surfaces
// are semantically related (playbook_memory workers reference runs the
// KB tracks; prior_lessons reference staffers the stats rank). Callers
// shouldn't have to know the topology.

import { readFile, readdir } from "node:fs/promises";
import { join } from "node:path";
import { normalizeInput, type NormalizedInput } from "./normalize.ts";
import { findNeighbors, loadRecommendation, loadStafferStats, computeSignature, type StafferStats, type PathwayRecommendation } from "./kb.ts";
import { GATEWAY, SIDECAR } from "./agent.ts";

export interface MemoryQueryResult {
  input: NormalizedInput;
  playbook_workers: Array<{
    doc_id: string;
    name: string;
    score: number;
    playbook_boost: number;
    playbook_citations: string[];
  }>;
  pathway_recommendation: PathwayRecommendation | null;
  neighbor_signatures: Array<{
    sig_hash: string;
    events_digest: string;
    similarity: number;
    weighted_score: number;
    best_staffer_id: string | null;
  }>;
  prior_lessons: Array<{
    date: string;
    client: string;
    cities: string;
    lesson: string;
  }>;
  top_staffers: StafferStats[];
  discovered_patterns: {
    sig_hash: string;
    top_workers: Array<{ name: string; endorsements: number }>;
  } | null;
  latency_ms: {
    normalize: number;
    playbook_search: number;
    kb_neighbors: number;
    staffer_stats: number;
    prior_lessons: number;
    total: number;
  };
}

// Main entry. Normalizes the input, then fans out to every memory
// source in parallel. Each source is best-effort: a down dependency
// just leaves its field empty rather than breaking the query.
export async function queryMemory(raw: unknown): Promise<MemoryQueryResult> {
  const t0 = Date.now();

  // Normalize input first — sets the tone for every downstream call.
  const tNorm = Date.now();
  const input = await normalizeInput(raw);
  const normalize_ms = Date.now() - tNorm;

  // Synthesize a minimal scenario spec from normalized input for sig
  // computation + KB lookup. Only needed if we have at least role + city.
  const pseudoSpec = (input.role && input.city && input.state) ? {
    client: input.client ?? "(unknown)",
    events: [{
      kind: input.intent === "rescue" ? "misplacement" : "baseline_fill",
      role: input.role,
      count: input.count ?? 1,
      city: input.city,
      state: input.state,
    }],
  } : null;

  // Fire everything that CAN fire in parallel.
  const tPb = Date.now();
  const playbookPromise: Promise<MemoryQueryResult["playbook_workers"]> =
    (input.role && input.city && input.state)
      ? fetch(`${GATEWAY}/vectors/hybrid`, {
          method: "POST",
          headers: { "content-type": "application/json" },
          body: JSON.stringify({
            index_name: "workers_500k_v1",
            sql_filter: `role = '${input.role.replace(/'/g, "''")}' AND city = '${input.city.replace(/'/g, "''")}' AND state = '${input.state}' AND CAST(availability AS DOUBLE) > 0.5`,
            question: `${input.role} ${input.city} ${input.state}`,
            top_k: 10,
            generate: false,
            use_playbook_memory: true,
            playbook_memory_k: 100,
          }),
        }).then(r => r.ok ? r.json() : { sources: [] })
          .then((d: any) => (d.sources ?? []).map((s: any) => ({
            doc_id: s.doc_id,
            name: s.chunk_text?.split("—")[0]?.trim() ?? "?",
            score: s.score ?? 0,
            playbook_boost: s.playbook_boost ?? 0,
            playbook_citations: s.playbook_citations ?? [],
          })))
          .catch(() => [])
      : Promise.resolve([]);

  const tKb = Date.now();
  const recPromise = pseudoSpec
    ? loadRecommendation(pseudoSpec).catch(() => null)
    : Promise.resolve(null);

  const neighborsPromise = pseudoSpec
    ? findNeighbors(pseudoSpec, 5).catch(() => [])
    : Promise.resolve([]);

  const tLess = Date.now();
  const lessonsPromise: Promise<MemoryQueryResult["prior_lessons"]> =
    (input.city && input.state)
      ? loadRelevantLessons(input.city, input.state).catch(() => [])
      : Promise.resolve([]);

  const tStaff = Date.now();
  const staffersPromise = loadStafferStats().catch(() => []);

  // Parallel await
  const [playbook_workers, pathway_recommendation, neighbors_raw, prior_lessons, staffers] =
    await Promise.all([playbookPromise, recPromise, neighborsPromise, lessonsPromise, staffersPromise]);

  // Derived: top-k staffers by competence, from recent activity.
  const top_staffers = staffers
    .filter(s => s.total_runs > 0)
    .sort((a, b) => b.competence_score - a.competence_score)
    .slice(0, 5);

  // Derived: discovered patterns for this sig (workers endorsed ≥ 2 staffers).
  let discovered_patterns: MemoryQueryResult["discovered_patterns"] = null;
  if (pseudoSpec) {
    const sig_hash = computeSignature(pseudoSpec);
    const workers = await collectTopEndorsedWorkers(sig_hash, input.role, input.city, input.state).catch(() => []);
    if (workers.length > 0) discovered_patterns = { sig_hash, top_workers: workers };
  }

  return {
    input,
    playbook_workers,
    pathway_recommendation,
    neighbor_signatures: neighbors_raw.map(n => ({
      sig_hash: n.sig.sig_hash,
      events_digest: n.sig.events_digest,
      similarity: n.similarity,
      weighted_score: n.weighted_score,
      best_staffer_id: n.best_staffer_id,
    })),
    prior_lessons,
    top_staffers,
    discovered_patterns,
    latency_ms: {
      normalize: normalize_ms,
      playbook_search: Date.now() - tPb,
      kb_neighbors: Date.now() - tKb,
      staffer_stats: Date.now() - tStaff,
      prior_lessons: Date.now() - tLess,
      total: Date.now() - t0,
    },
  };
}

async function loadRelevantLessons(city: string, state: string | null): Promise<MemoryQueryResult["prior_lessons"]> {
  try {
    const dir = join("data", "_playbook_lessons");
    const files = await readdir(dir).catch(() => [] as string[]);
    const out: MemoryQueryResult["prior_lessons"] = [];
    for (const f of files) {
      if (!f.endsWith(".json")) continue;
      try {
        const raw = await readFile(join(dir, f), "utf8");
        const rec = JSON.parse(raw);
        const lessonCities = (rec.cities ?? "").split(",");
        const lessonStates = (rec.states ?? "").split(",");
        if (lessonCities.includes(city) || (state && lessonStates.includes(state))) {
          out.push({
            date: rec.date,
            client: rec.client,
            cities: rec.cities,
            lesson: rec.lesson.slice(0, 500),
          });
        }
      } catch { /* skip malformed */ }
    }
    out.sort((a, b) => (b.date ?? "").localeCompare(a.date ?? ""));
    return out.slice(0, 3);
  } catch {
    return [];
  }
}

async function collectTopEndorsedWorkers(
  sig_hash: string,
  role: string | null,
  city: string | null,
  state: string | null,
): Promise<Array<{ name: string; endorsements: number }>> {
  if (!role || !city || !state) return [];
  // Pull from playbook_memory — each successful fill was endorsed;
  // count by (name, role, city, state) across past playbooks.
  try {
    const resp = await fetch(`${GATEWAY}/query/sql`, {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({
        sql: `SELECT operation, result FROM successful_playbooks_live
              WHERE operation LIKE 'fill: ${role.replace(/'/g, "''")} %'
                AND operation LIKE '%in ${city.replace(/'/g, "''")}, ${state}%'
              ORDER BY timestamp DESC LIMIT 50`,
      }),
    });
    if (!resp.ok) return [];
    const data: any = await resp.json();
    // successful_playbooks_live.result has the shape
    //   "N/N filled → Name A, Name B, Name C"
    // or historical "Name A | Name B | Name C". Handle both.
    const counts = new Map<string, number>();
    for (const row of data.rows ?? []) {
      const raw = String(row.result ?? "");
      const afterArrow = raw.includes("→") ? raw.split("→")[1] : raw;
      const names = afterArrow
        .split(/[,|]/)
        .map((n: string) => n.trim())
        .filter(n => n && !/^\d+\/\d+/.test(n) && !n.toLowerCase().startsWith("filled"));
      for (const n of names) counts.set(n, (counts.get(n) ?? 0) + 1);
    }
    return [...counts.entries()]
      .sort((a, b) => b[1] - a[1])
      .slice(0, 5)
      .map(([name, endorsements]) => ({ name, endorsements }));
  } catch {
    return [];
  }
}