import { NextRequest, NextResponse } from "next/server";
import { telegramApproverDb, telegramSettingsDb } from "@/lib/db";
import { isTelegramConfigured, registerTelegramWebhook } from "@/lib/telegram";
import { TelegramApprover } from "@/lib/types";

export const dynamic = "force-dynamic";

export async function GET() {
  const settings = telegramSettingsDb.get();
  return NextResponse.json({
    approvers: telegramApproverDb.getAll(),
    baseUrl: settings.baseUrl,
    greetingText: settings.greetingText,
    cardNumber: settings.cardNumber,
    cardHolderName: settings.cardHolderName,
    botConfigured: isTelegramConfigured(),
    webhookSecretConfigured: Boolean(process.env.TELEGRAM_WEBHOOK_SECRET),
  });
}

export async function PUT(request: NextRequest) {
  try {
    const body = (await request.json()) as {
      approvers?: TelegramApprover[];
      baseUrl?: string;
      botToken?: string;
      greetingText?: string;
      cardNumber?: string;
      cardHolderName?: string;
    };
    if (!Array.isArray(body.approvers)) {
      return NextResponse.json({ error: "approvers must be an array" }, { status: 400 });
    }

    const seen = new Set<string>();
    const approvers: TelegramApprover[] = [];
    for (const item of body.approvers) {
      const userId = String(item.userId || "").trim();
      if (!/^\d+$/.test(userId)) {
        return NextResponse.json({ error: `Invalid Telegram user ID: ${userId}` }, { status: 400 });
      }
      if (!seen.has(userId)) {
        seen.add(userId);
        approvers.push({ userId, label: String(item.label || "").trim().slice(0, 100) });
      }
    }

    const baseUrl = String(body.baseUrl || "https://api.telegram.org").trim().replace(/\/$/, "");
    let parsedUrl: URL;
    try {
      parsedUrl = new URL(baseUrl);
    } catch {
      return NextResponse.json({ error: "Invalid Telegram API base URL" }, { status: 400 });
    }
    if (!["http:", "https:"].includes(parsedUrl.protocol) || parsedUrl.username || parsedUrl.password) {
      return NextResponse.json({ error: "Telegram API base URL must use HTTP or HTTPS without credentials" }, { status: 400 });
    }

    const botToken = body.botToken?.trim();
    const greetingText = String(body.greetingText || "").trim().slice(0, 1000);
    const cardNumber = String(body.cardNumber || "").trim().slice(0, 100);
    const cardHolderName = String(body.cardHolderName || "").trim().slice(0, 200);
    if (!greetingText) {
      return NextResponse.json({ error: "Greeting message is required" }, { status: 400 });
    }
    telegramApproverDb.replaceAll(approvers);
    telegramSettingsDb.update({
      baseUrl,
      greetingText,
      cardNumber,
      cardHolderName,
      ...(botToken ? { botToken } : {}),
    });

    return NextResponse.json({
      approvers: telegramApproverDb.getAll(),
      baseUrl: telegramSettingsDb.get().baseUrl,
      greetingText,
      cardNumber,
      cardHolderName,
      botConfigured: isTelegramConfigured(),
      webhookSecretConfigured: Boolean(process.env.TELEGRAM_WEBHOOK_SECRET),
    });
  } catch (error) {
    console.error("Telegram settings update failed:", error);
    return NextResponse.json({ error: "Failed to update Telegram settings" }, { status: 500 });
  }
}

export async function POST() {
  try {
    await registerTelegramWebhook();
    return NextResponse.json({ message: "Telegram webhook registered successfully" });
  } catch (error) {
    const message = error instanceof Error ? error.message : "Failed to register Telegram webhook";
    console.error("Telegram webhook registration failed:", error);
    return NextResponse.json({ error: message }, { status: 502 });
  }
}