import { randomUUID } from 'node:crypto';
import { CamelCasePlugin, Kysely } from 'kysely';
import { PostgresJSDialect } from 'kysely-postgres-js';
import * as postgres from 'postgres';

/**
 * Isolated test database connection string. The dev DB is `docmost`; tests run
 * against a dedicated `docmost_test` that global-setup drops + recreates +
 * migrates so nothing here touches dev data. Overridable via env (global-setup
 * also sets it so the value is consistent across the run).
 */
export const TEST_DATABASE_URL =
  process.env.TEST_DATABASE_URL ??
  'postgresql://docmost:docmost_dev_pw@localhost:5432/docmost_test';

/**
 * Build a Kysely instance that MIRRORS the app's setup in database.module.ts:
 * PostgresJSDialect over postgres(), CamelCasePlugin, and the bigint type
 * parsing (to:20 / from:[20,1700] / serialize toString / parse parseInt). The
 * repos rely on camelCase columns + bigint-as-number, so the test Kysely must
 * match or queries break.
 */
export function buildTestDb(url: string = TEST_DATABASE_URL): Kysely<any> {
  return new Kysely<any>({
    dialect: new PostgresJSDialect({
      postgres: postgres(url, {
        max: 5,
        onnotice: () => {},
        types: {
          bigint: {
            to: 20,
            from: [20, 1700],
            serialize: (value: number) => value.toString(),
            parse: (value: string) => Number.parseInt(value),
          },
        },
      }),
    }),
    plugins: [new CamelCasePlugin()],
  });
}

let singleton: Kysely<any> | undefined;

/** Lazily-built shared Kysely for the test suite (one per worker; maxWorkers=1). */
export function getTestDb(): Kysely<any> {
  if (!singleton) {
    singleton = buildTestDb();
  }
  return singleton;
}

export async function destroyTestDb(): Promise<void> {
  if (singleton) {
    await singleton.destroy();
    singleton = undefined;
  }
}

// --- Seeding helpers ---------------------------------------------------------
// Insert minimal valid rows (only the columns the tests need + NOT NULL ones).
// Plain randomUUID() is fine for FK integrity in tests (the app uses uuid v7).

export async function createWorkspace(
  db: Kysely<any>,
  overrides: { settings?: unknown; name?: string } = {},
): Promise<{ id: string; settings: any }> {
  const id = randomUUID();
  const row = await db
    .insertInto('workspaces')
    .values({
      id,
      name: overrides.name ?? `ws-${id.slice(0, 8)}`,
      // hostname is uniquely constrained; keep it unique per workspace.
      hostname: `host-${id.slice(0, 8)}`,
      settings: overrides.settings === undefined ? null : (overrides.settings as any),
    })
    .returning(['id', 'settings'])
    .executeTakeFirstOrThrow();
  return { id: row.id as string, settings: row.settings };
}

export async function createUser(
  db: Kysely<any>,
  workspaceId: string,
  overrides: { email?: string; name?: string } = {},
): Promise<{ id: string }> {
  const id = randomUUID();
  const row = await db
    .insertInto('users')
    .values({
      id,
      email: overrides.email ?? `user-${id.slice(0, 8)}@example.test`,
      name: overrides.name ?? `user-${id.slice(0, 8)}`,
      workspaceId,
    })
    .returning(['id'])
    .executeTakeFirstOrThrow();
  return { id: row.id as string };
}

export async function createSpace(
  db: Kysely<any>,
  workspaceId: string,
  overrides: { slug?: string; name?: string } = {},
): Promise<{ id: string }> {
  const id = randomUUID();
  const row = await db
    .insertInto('spaces')
    .values({
      id,
      name: overrides.name ?? `space-${id.slice(0, 8)}`,
      // slug is unique per workspace + NOT NULL.
      slug: overrides.slug ?? `space-${id.slice(0, 8)}`,
      workspaceId,
    })
    .returning(['id'])
    .executeTakeFirstOrThrow();
  return { id: row.id as string };
}

export async function createPage(
  db: Kysely<any>,
  args: { workspaceId: string; spaceId: string; title?: string },
): Promise<{ id: string }> {
  const id = randomUUID();
  const row = await db
    .insertInto('pages')
    .values({
      id,
      // slug_id is NOT NULL + globally unique.
      slugId: `slug-${id.slice(0, 8)}`,
      title: args.title ?? `page-${id.slice(0, 8)}`,
      spaceId: args.spaceId,
      workspaceId: args.workspaceId,
    })
    .returning(['id'])
    .executeTakeFirstOrThrow();
  return { id: row.id as string };
}

export async function createRole(
  db: Kysely<any>,
  args: {
    workspaceId: string;
    creatorId?: string | null;
    name: string;
    emoji?: string | null;
    instructions?: string;
    enabled?: boolean;
    deletedAt?: Date | null;
  },
): Promise<{ id: string }> {
  const id = randomUUID();
  const row = await db
    .insertInto('aiAgentRoles')
    .values({
      id,
      workspaceId: args.workspaceId,
      creatorId: args.creatorId ?? null,
      name: args.name,
      emoji: args.emoji ?? null,
      instructions: args.instructions ?? 'be helpful',
      enabled: args.enabled ?? true,
      deletedAt: args.deletedAt ?? null,
    })
    .returning(['id'])
    .executeTakeFirstOrThrow();
  return { id: row.id as string };
}

export async function createChat(
  db: Kysely<any>,
  args: {
    workspaceId: string;
    creatorId: string;
    roleId?: string | null;
    title?: string;
  },
): Promise<{ id: string }> {
  const id = randomUUID();
  const row = await db
    .insertInto('aiChats')
    .values({
      id,
      workspaceId: args.workspaceId,
      creatorId: args.creatorId,
      roleId: args.roleId ?? null,
      title: args.title ?? `chat-${id.slice(0, 8)}`,
    })
    .returning(['id'])
    .executeTakeFirstOrThrow();
  return { id: row.id as string };
}