import type Database from 'better-sqlite3';

export type RedditAccountStatus = 'verified' | 'login-required' | 'disabled' | 'legacy-unassigned';

export interface RedditAccountPublicRecord {
  accountId: string;
  redditUsername: string;
  matrixUserId: string | null;
  status: RedditAccountStatus;
  isActive: boolean;
  createdAt: number;
  updatedAt: number;
  lastVerifiedAt: number | null;
  lastImportedAt: number | null;
}

/** Private credential-bearing record. Never return this from a web API. */
export interface RedditAccountPrivateRecord extends RedditAccountPublicRecord {
  cookiesJson: string;
  matrixCredentialsJson: string;
}

export interface VerifiedRedditAccountInput {
  accountId: string;
  redditUsername: string;
  matrixUserId: string;
  cookiesJson: string;
  matrixCredentialsJson: string;
  now?: number;
}

type AccountRow = {
  account_id: string;
  reddit_username: string;
  matrix_user_id: string | null;
  status: RedditAccountStatus;
  is_active: number;
  cookies_json: string;
  matrix_credentials_json: string;
  created_at: number;
  updated_at: number;
  last_verified_at: number | null;
  last_imported_at: number | null;
};

export class RedditAccountsRepository {
  constructor(private readonly db: Database.Database) {}

  listPublic(): RedditAccountPublicRecord[] {
    const rows = this.db.prepare(`
      SELECT account_id, reddit_username, matrix_user_id, status, is_active,
        created_at, updated_at, last_verified_at, last_imported_at
      FROM reddit_accounts
      ORDER BY is_active DESC, reddit_username COLLATE NOCASE, account_id
    `).all() as AccountRow[];
    return rows.map(mapPublicAccount);
  }

  /** Private lookup for the runtime/session factory. Contains credentials. */
  get(accountId: string): RedditAccountPrivateRecord | null {
    const row = this.db.prepare('SELECT * FROM reddit_accounts WHERE account_id = ?')
      .get(accountId) as AccountRow | undefined;
    return row ? mapPrivateAccount(row) : null;
  }

  getActive(): RedditAccountPublicRecord[] {
    const rows = this.db.prepare(`
      SELECT account_id, reddit_username, matrix_user_id, status, is_active,
        created_at, updated_at, last_verified_at, last_imported_at
      FROM reddit_accounts
      WHERE is_active = 1 AND status != 'legacy-unassigned'
      ORDER BY reddit_username COLLATE NOCASE, account_id
    `).all() as AccountRow[];
    return rows.map(mapPublicAccount);
  }

  upsertVerified(input: VerifiedRedditAccountInput): RedditAccountPublicRecord {
    requireText(input.accountId, 'accountId');
    requireText(input.redditUsername, 'redditUsername');
    requireText(input.matrixUserId, 'matrixUserId');
    requireJson(input.cookiesJson, 'cookiesJson');
    requireJson(input.matrixCredentialsJson, 'matrixCredentialsJson');
    const now = input.now ?? Date.now();
    this.db.prepare(`
      INSERT INTO reddit_accounts (
        account_id, reddit_username, matrix_user_id, status, is_active,
        cookies_json, matrix_credentials_json, created_at, updated_at,
        last_verified_at, last_imported_at
      ) VALUES (
        @accountId, @redditUsername, @matrixUserId, 'verified', 1,
        @cookiesJson, @matrixCredentialsJson, @now, @now, @now, @now
      )
      ON CONFLICT(account_id) DO UPDATE SET
        reddit_username = excluded.reddit_username,
        matrix_user_id = excluded.matrix_user_id,
        status = 'verified',
        is_active = 1,
        cookies_json = excluded.cookies_json,
        matrix_credentials_json = excluded.matrix_credentials_json,
        updated_at = excluded.updated_at,
        last_verified_at = excluded.last_verified_at,
        last_imported_at = excluded.last_imported_at
    `).run({ ...input, now });
    return publicFromPrivate(this.getRequired(input.accountId));
  }

  /** Store a self-refreshed Matrix token without touching cookies or status. */
  updateMatrixCredentials(
    accountId: string,
    matrixCredentialsJson: string,
    now: number = Date.now(),
  ): boolean {
    requireText(accountId, 'accountId');
    requireJson(matrixCredentialsJson, 'matrixCredentialsJson');
    return this.db.prepare(`
      UPDATE reddit_accounts
      SET matrix_credentials_json = ?, updated_at = ?, last_verified_at = ?
      WHERE account_id = ? AND status != 'legacy-unassigned'
    `).run(matrixCredentialsJson, now, now, accountId).changes === 1;
  }

  setActive(accountId: string, active = true, now: number = Date.now()): boolean {
    const status = active ? 'verified' : 'disabled';
    return this.db.prepare(`
      UPDATE reddit_accounts
      SET is_active = ?, status = ?, updated_at = ?
      WHERE account_id = ? AND status != 'legacy-unassigned'
    `).run(active ? 1 : 0, status, now, accountId).changes === 1;
  }

  markLoginRequired(accountId: string, now: number = Date.now()): boolean {
    return this.db.prepare(`
      UPDATE reddit_accounts
      SET status = 'login-required', updated_at = ?
      WHERE account_id = ? AND status != 'legacy-unassigned'
    `).run(now, accountId).changes === 1;
  }

  private getRequired(accountId: string): RedditAccountPrivateRecord {
    const account = this.get(accountId);
    if (!account) throw new Error(`Reddit account ${accountId} was not persisted`);
    return account;
  }
}

function mapPublicAccount(row: AccountRow): RedditAccountPublicRecord {
  return {
    accountId: row.account_id,
    redditUsername: row.reddit_username,
    matrixUserId: row.matrix_user_id,
    status: row.status,
    isActive: row.is_active === 1,
    createdAt: row.created_at,
    updatedAt: row.updated_at,
    lastVerifiedAt: row.last_verified_at,
    lastImportedAt: row.last_imported_at,
  };
}

function mapPrivateAccount(row: AccountRow): RedditAccountPrivateRecord {
  return {
    ...mapPublicAccount(row),
    cookiesJson: row.cookies_json,
    matrixCredentialsJson: row.matrix_credentials_json,
  };
}

function publicFromPrivate(record: RedditAccountPrivateRecord): RedditAccountPublicRecord {
  const { cookiesJson: _cookies, matrixCredentialsJson: _matrix, ...publicRecord } = record;
  return publicRecord;
}

export interface AccountConversationRecord {
  accountId: string;
  conversationId: string;
  username: string;
  roomName: string | null;
  payloadJson: string;
  updatedAt: number;
}

export interface AccountSyncStateRecord {
  accountId: string;
  nextBatch: string | null;
  lastFullSyncAt: number | null;
  lastDeltaSyncAt: number | null;
  cooldownJson: string | null;
  updatedAt: number;
}

export interface AccountMediaRecord {
  accountId: string;
  mediaId: string;
  chatUsername: string | null;
  chatRoomId: string | null;
  sender: string;
  timestamp: number;
  originalUrl: string;
  fileName: string;
  relativePath: string;
  createdAt: number;
}

export type RedditRecipientAccountStatus = 'active' | 'suspended' | 'deleted';

export interface RedditRecipientAccountStatusRecord {
  username: string;
  status: RedditRecipientAccountStatus;
  checkedAt: number;
}

type ConversationRow = {
  account_id: string;
  conversation_id: string;
  username: string;
  room_name: string | null;
  payload_json: string;
  updated_at: number;
};

type SyncStateRow = {
  account_id: string;
  next_batch: string | null;
  last_full_sync_at: number | null;
  last_delta_sync_at: number | null;
  cooldown_json: string | null;
  updated_at: number;
};

type MediaRow = {
  account_id: string;
  media_id: string;
  chat_username: string | null;
  chat_room_id: string | null;
  sender: string;
  timestamp: number;
  original_url: string;
  file_name: string;
  relative_path: string;
  created_at: number;
};

/** Account-scoped DB persistence for chat cache state and downloaded-media metadata. */
export class AccountContentRepository {
  constructor(private readonly db: Database.Database) {}

  upsertConversation(input: Omit<AccountConversationRecord, 'updatedAt'> & { updatedAt?: number }): void {
    requireText(input.accountId, 'accountId');
    requireText(input.conversationId, 'conversationId');
    requireText(input.username, 'username');
    requireJson(input.payloadJson, 'payloadJson');
    this.db.prepare(`
      INSERT INTO reddit_conversations (
        account_id, conversation_id, username, room_name, payload_json, updated_at
      ) VALUES (@accountId, @conversationId, @username, @roomName, @payloadJson, @updatedAt)
      ON CONFLICT(account_id, conversation_id) DO UPDATE SET
        username = excluded.username,
        room_name = excluded.room_name,
        payload_json = excluded.payload_json,
        updated_at = excluded.updated_at
    `).run({ ...input, roomName: input.roomName ?? null, updatedAt: input.updatedAt ?? Date.now() });
  }

  getConversation(accountId: string, conversationId: string): AccountConversationRecord | null {
    const row = this.db.prepare(`
      SELECT * FROM reddit_conversations WHERE account_id = ? AND conversation_id = ?
    `).get(accountId, conversationId) as ConversationRow | undefined;
    return row ? mapConversation(row) : null;
  }

  listConversations(accountId: string): AccountConversationRecord[] {
    const rows = this.db.prepare(`
      SELECT * FROM reddit_conversations WHERE account_id = ?
      ORDER BY updated_at DESC, conversation_id
    `).all(accountId) as ConversationRow[];
    return rows.map(mapConversation);
  }

  deleteConversation(accountId: string, conversationId: string): boolean {
    return this.db.prepare(`
      DELETE FROM reddit_conversations WHERE account_id = ? AND conversation_id = ?
    `).run(accountId, conversationId).changes === 1;
  }

  saveSyncState(input: Omit<AccountSyncStateRecord, 'updatedAt'> & { updatedAt?: number }): void {
    if (input.cooldownJson !== null) requireJson(input.cooldownJson, 'cooldownJson');
    this.db.prepare(`
      INSERT INTO reddit_account_sync_state (
        account_id, next_batch, last_full_sync_at, last_delta_sync_at, cooldown_json, updated_at
      ) VALUES (@accountId, @nextBatch, @lastFullSyncAt, @lastDeltaSyncAt, @cooldownJson, @updatedAt)
      ON CONFLICT(account_id) DO UPDATE SET
        next_batch = excluded.next_batch,
        last_full_sync_at = excluded.last_full_sync_at,
        last_delta_sync_at = excluded.last_delta_sync_at,
        cooldown_json = excluded.cooldown_json,
        updated_at = excluded.updated_at
    `).run({ ...input, updatedAt: input.updatedAt ?? Date.now() });
  }

  getSyncState(accountId: string): AccountSyncStateRecord | null {
    const row = this.db.prepare('SELECT * FROM reddit_account_sync_state WHERE account_id = ?')
      .get(accountId) as SyncStateRow | undefined;
    return row ? mapSyncState(row) : null;
  }

  upsertMedia(input: AccountMediaRecord): void {
    requireText(input.accountId, 'accountId');
    requireText(input.mediaId, 'mediaId');
    this.db.prepare(`
      INSERT INTO reddit_media (
        account_id, media_id, chat_username, chat_room_id, sender, timestamp,
        original_url, file_name, relative_path, created_at
      ) VALUES (
        @accountId, @mediaId, @chatUsername, @chatRoomId, @sender, @timestamp,
        @originalUrl, @fileName, @relativePath, @createdAt
      )
      ON CONFLICT(account_id, media_id) DO UPDATE SET
        chat_username = excluded.chat_username,
        chat_room_id = excluded.chat_room_id,
        sender = excluded.sender,
        timestamp = excluded.timestamp,
        original_url = excluded.original_url,
        file_name = excluded.file_name,
        relative_path = excluded.relative_path,
        created_at = excluded.created_at
    `).run(input);
  }

  getMedia(accountId: string, mediaId: string): AccountMediaRecord | null {
    const row = this.db.prepare(`
      SELECT * FROM reddit_media WHERE account_id = ? AND media_id = ?
    `).get(accountId, mediaId) as MediaRow | undefined;
    return row ? mapMedia(row) : null;
  }

  getMediaByOriginalUrl(accountId: string, originalUrl: string): AccountMediaRecord | null {
    const row = this.db.prepare(`
      SELECT * FROM reddit_media
      WHERE account_id = ? AND original_url = ?
      ORDER BY timestamp, media_id
      LIMIT 1
    `).get(accountId, originalUrl) as MediaRow | undefined;
    return row ? mapMedia(row) : null;
  }

  listMedia(accountId: string): AccountMediaRecord[] {
    const rows = this.db.prepare(`
      SELECT * FROM reddit_media WHERE account_id = ?
      ORDER BY timestamp DESC, media_id
    `).all(accountId) as MediaRow[];
    return rows.map(mapMedia);
  }

  deleteMedia(accountId: string, mediaId: string): boolean {
    return this.db.prepare(`
      DELETE FROM reddit_media WHERE account_id = ? AND media_id = ?
    `).run(accountId, mediaId).changes === 1;
  }
}

type RecipientAccountStatusRow = {
  username: string;
  status: RedditRecipientAccountStatus;
  checked_at: number;
};

/** Process-global Reddit profile availability, shared by conversations across owning accounts. */
export class RedditRecipientAccountStatusRepository {
  constructor(private readonly db: Database.Database) {}

  get(username: string): RedditRecipientAccountStatusRecord | null {
    const row = this.db.prepare(`
      SELECT username, status, checked_at
      FROM reddit_recipient_account_status
      WHERE username = ? COLLATE NOCASE
    `).get(username) as RecipientAccountStatusRow | undefined;
    return row ? { username: row.username, status: row.status, checkedAt: row.checked_at } : null;
  }

  upsert(username: string, status: RedditRecipientAccountStatus, checkedAt = Date.now()): void {
    requireText(username, 'username');
    this.db.prepare(`
      INSERT INTO reddit_recipient_account_status (username, status, checked_at)
      VALUES (?, ?, ?)
      ON CONFLICT(username) DO UPDATE SET
        status = excluded.status,
        checked_at = excluded.checked_at
    `).run(username, status, checkedAt);
  }
}

function mapConversation(row: ConversationRow): AccountConversationRecord {
  return {
    accountId: row.account_id,
    conversationId: row.conversation_id,
    username: row.username,
    roomName: row.room_name,
    payloadJson: row.payload_json,
    updatedAt: row.updated_at,
  };
}

function mapSyncState(row: SyncStateRow): AccountSyncStateRecord {
  return {
    accountId: row.account_id,
    nextBatch: row.next_batch,
    lastFullSyncAt: row.last_full_sync_at,
    lastDeltaSyncAt: row.last_delta_sync_at,
    cooldownJson: row.cooldown_json,
    updatedAt: row.updated_at,
  };
}

function mapMedia(row: MediaRow): AccountMediaRecord {
  return {
    accountId: row.account_id,
    mediaId: row.media_id,
    chatUsername: row.chat_username,
    chatRoomId: row.chat_room_id,
    sender: row.sender,
    timestamp: row.timestamp,
    originalUrl: row.original_url,
    fileName: row.file_name,
    relativePath: row.relative_path,
    createdAt: row.created_at,
  };
}

function requireText(value: string, name: string): void {
  if (!value.trim()) throw new Error(`${name} must not be empty`);
}

function requireJson(value: string, name: string): void {
  try {
    JSON.parse(value);
  } catch {
    throw new Error(`${name} must be valid JSON`);
  }
}