/**
 * ArtifactStore.ts — Dexie/IndexedDB persistence for workspace artifacts (FASE 7)
 *
 * Artifacts are first-class workspace objects: code files, HTML pages,
 * Markdown docs, CSV tables, JSON data, SVG images generated by the agent.
 *
 * Uses the same Dexie instance pattern as the rest of the app.
 * Zero external dependencies beyond Dexie (already in package).
 */

import Dexie, { type Table } from "dexie";

export type ArtifactKind =
  | "code"      // runnable code (python, typescript, javascript, rust, …)
  | "html"      // full HTML page → sandboxed iframe
  | "markdown"  // rendered markdown document
  | "csv"       // tabular data → rendered table
  | "json"      // structured data
  | "svg"       // vector image
  | "text";     // plain text / unknown

export interface Artifact {
  id:          string;            // nanoid / uuid
  kind:        ArtifactKind;
  language?:   string;            // for "code" kind: python, typescript, …
  title:       string;            // short descriptive name
  content:     string;            // raw text content
  sessionId?:  string;            // conversation session it belongs to
  messageId?:  string;            // message that generated it
  createdAt:   number;            // unix ms
  updatedAt:   number;            // unix ms
  version:     number;            // monotonic — bump on edit
  pinned:      boolean;           // user pinned to sidebar
  tags:        string[];
}

class ArtifactDatabase extends Dexie {
  artifacts!: Table<Artifact, string>;

  constructor() {
    super("agente_artifacts_v1");
    this.version(1).stores({
      artifacts: "id, kind, sessionId, createdAt, updatedAt, pinned",
    });
  }
}

let _db: ArtifactDatabase | null = null;

function db(): ArtifactDatabase {
  if (!_db) _db = new ArtifactDatabase();
  return _db;
}

// ── CRUD ─────────────────────────────────────────────────────────────────────

export async function saveArtifact(artifact: Artifact): Promise<void> {
  await db().artifacts.put(artifact);
}

export async function getArtifact(id: string): Promise<Artifact | undefined> {
  return db().artifacts.get(id);
}

export async function updateArtifact(id: string, patch: Partial<Omit<Artifact, "id" | "createdAt">>): Promise<void> {
  const existing = await db().artifacts.get(id);
  if (!existing) return;
  await db().artifacts.put({
    ...existing,
    ...patch,
    id,
    updatedAt: Date.now(),
    version: existing.version + 1,
  });
}

export async function deleteArtifact(id: string): Promise<void> {
  await db().artifacts.delete(id);
}

export async function listArtifacts(opts: {
  sessionId?:  string;
  kind?:       ArtifactKind;
  pinned?:     boolean;
  limit?:      number;
} = {}): Promise<Artifact[]> {
  let query = db().artifacts.orderBy("updatedAt").reverse();
  const { sessionId, kind, pinned, limit } = opts;

  const results = await query.filter(a => {
    if (sessionId && a.sessionId !== sessionId) return false;
    if (kind      && a.kind      !== kind)      return false;
    if (pinned    !== undefined  && a.pinned    !== pinned) return false;
    return true;
  }).toArray();

  return limit ? results.slice(0, limit) : results;
}

export async function searchArtifacts(query: string): Promise<Artifact[]> {
  const q = query.toLowerCase();
  return db().artifacts
    .filter(a => a.title.toLowerCase().includes(q) || a.content.toLowerCase().includes(q))
    .toArray();
}

export async function clearSessionArtifacts(sessionId: string): Promise<number> {
  return db().artifacts.where("sessionId").equals(sessionId).delete();
}