// Custom error class for Telegram API errors
export class TelegramError extends Error {
  constructor(
    message: string,
    public readonly code?: number,
    public readonly description?: string
  ) {
    super(message);
    this.name = 'TelegramError';
  }
}

// Telegram API 메시지 전송
export async function sendMessage(
  token: string,
  chatId: number,
  text: string,
  options?: {
    parse_mode?: 'HTML' | 'Markdown' | 'MarkdownV2';
    reply_to_message_id?: number;
    disable_notification?: boolean;
  }
): Promise<void> {
  try {
    const response = await fetch(
      `https://api.telegram.org/bot${token}/sendMessage`,
      {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          chat_id: chatId,
          text,
          parse_mode: options?.parse_mode || 'HTML',
          reply_to_message_id: options?.reply_to_message_id,
          disable_notification: options?.disable_notification,
        }),
      }
    );

    if (!response.ok) {
      let description = '';
      try {
        const errorData = await response.json() as { description?: string };
        description = errorData.description || '';
      } catch {
        // JSON 파싱 실패 시 무시
      }
      throw new TelegramError(
        `Failed to send message: ${response.status}`,
        response.status,
        description
      );
    }
  } catch (error) {
    if (error instanceof TelegramError) {
      throw error;
    }
    throw new TelegramError(
      'Network error while sending message',
      undefined,
      error instanceof Error ? error.message : String(error)
    );
  }
}

// Webhook 설정 (Secret Token 포함)
export async function setWebhook(
  token: string,
  webhookUrl: string,
  secretToken: string
): Promise<{ ok: boolean; description?: string }> {
  const response = await fetch(
    `https://api.telegram.org/bot${token}/setWebhook`,
    {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        url: webhookUrl,
        secret_token: secretToken,
        allowed_updates: ['message', 'callback_query'],
        drop_pending_updates: true,
      }),
    }
  );

  return response.json();
}

// Webhook 정보 조회
export async function getWebhookInfo(
  token: string
): Promise<unknown> {
  const response = await fetch(
    `https://api.telegram.org/bot${token}/getWebhookInfo`
  );
  return response.json();
}

// Webhook 삭제
export async function deleteWebhook(
  token: string
): Promise<{ ok: boolean }> {
  const response = await fetch(
    `https://api.telegram.org/bot${token}/deleteWebhook`,
    { method: 'POST' }
  );
  return response.json();
}

// 인라인 키보드 타입
export interface InlineKeyboardButton {
  text: string;
  url?: string;
  callback_data?: string;
  web_app?: { url: string };
}

// 인라인 키보드와 함께 메시지 전송
export async function sendMessageWithKeyboard(
  token: string,
  chatId: number,
  text: string,
  keyboard: InlineKeyboardButton[][],
  options?: {
    parse_mode?: 'HTML' | 'Markdown' | 'MarkdownV2';
  }
): Promise<void> {
  try {
    const response = await fetch(
      `https://api.telegram.org/bot${token}/sendMessage`,
      {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          chat_id: chatId,
          text,
          parse_mode: options?.parse_mode || 'HTML',
          reply_markup: {
            inline_keyboard: keyboard,
          },
        }),
      }
    );

    if (!response.ok) {
      let description = '';
      try {
        const errorData = await response.json() as { description?: string };
        description = errorData.description || '';
      } catch {
        // JSON 파싱 실패 시 무시
      }
      throw new TelegramError(
        `Failed to send message with keyboard: ${response.status}`,
        response.status,
        description
      );
    }
  } catch (error) {
    if (error instanceof TelegramError) {
      throw error;
    }
    throw new TelegramError(
      'Network error while sending message with keyboard',
      undefined,
      error instanceof Error ? error.message : String(error)
    );
  }
}

// 타이핑 액션 전송
export async function sendChatAction(
  token: string,
  chatId: number,
  action: 'typing' | 'upload_photo' | 'upload_document' = 'typing'
): Promise<void> {
  try {
    const response = await fetch(
      `https://api.telegram.org/bot${token}/sendChatAction`,
      {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          chat_id: chatId,
          action,
        }),
      }
    );

    if (!response.ok) {
      let description = '';
      try {
        const errorData = await response.json() as { description?: string };
        description = errorData.description || '';
      } catch {
        // JSON 파싱 실패 시 무시
      }
      throw new TelegramError(
        `Failed to send chat action: ${response.status}`,
        response.status,
        description
      );
    }
  } catch (error) {
    if (error instanceof TelegramError) {
      throw error;
    }
    throw new TelegramError(
      'Network error while sending chat action',
      undefined,
      error instanceof Error ? error.message : String(error)
    );
  }
}

// Callback Query 응답 (버튼 클릭 알림)
export async function answerCallbackQuery(
  token: string,
  callbackQueryId: string,
  options?: {
    text?: string;
    show_alert?: boolean;
  }
): Promise<void> {
  try {
    const response = await fetch(
      `https://api.telegram.org/bot${token}/answerCallbackQuery`,
      {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          callback_query_id: callbackQueryId,
          text: options?.text,
          show_alert: options?.show_alert,
        }),
      }
    );

    if (!response.ok) {
      let description = '';
      try {
        const errorData = await response.json() as { description?: string };
        description = errorData.description || '';
      } catch {
        // JSON 파싱 실패 시 무시
      }
      throw new TelegramError(
        `Failed to answer callback query: ${response.status}`,
        response.status,
        description
      );
    }
  } catch (error) {
    if (error instanceof TelegramError) {
      throw error;
    }
    throw new TelegramError(
      'Network error while answering callback query',
      undefined,
      error instanceof Error ? error.message : String(error)
    );
  }
}

// 메시지 수정 (인라인 키보드 제거/변경용)
export async function editMessageText(
  token: string,
  chatId: number,
  messageId: number,
  text: string,
  options?: {
    parse_mode?: 'HTML' | 'Markdown' | 'MarkdownV2';
    reply_markup?: { inline_keyboard: InlineKeyboardButton[][] };
  }
): Promise<void> {
  try {
    const response = await fetch(
      `https://api.telegram.org/bot${token}/editMessageText`,
      {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          chat_id: chatId,
          message_id: messageId,
          text,
          parse_mode: options?.parse_mode || 'HTML',
          reply_markup: options?.reply_markup,
        }),
      }
    );

    if (!response.ok) {
      let description = '';
      try {
        const errorData = await response.json() as { description?: string };
        description = errorData.description || '';
      } catch {
        // JSON 파싱 실패 시 무시
      }
      throw new TelegramError(
        `Failed to edit message text: ${response.status}`,
        response.status,
        description
      );
    }
  } catch (error) {
    if (error instanceof TelegramError) {
      throw error;
    }
    throw new TelegramError(
      'Network error while editing message text',
      undefined,
      error instanceof Error ? error.message : String(error)
    );
  }
}