import { serve } from "https://deno.land/std@0.190.0/http/server.ts";

const corsHeaders = {
  "Access-Control-Allow-Origin": "*",
  "Access-Control-Allow-Headers": "authorization, x-client-info, apikey, content-type",
};

interface CreatePaymentRequest {
  order_id: string;
  amount: number;
  description: string;
  method?: 'qris' | 'paypal';
}

serve(async (req: Request) => {
  // Handle CORS preflight
  if (req.method === "OPTIONS") {
    return new Response(null, { headers: corsHeaders });
  }

  if (req.method !== "POST") {
    return new Response("Method not allowed", { status: 405, headers: corsHeaders });
  }

  try {
    const body: CreatePaymentRequest = await req.json();
    const { order_id, amount, description, method = 'qris' } = body;

    if (!order_id || !amount) {
      return new Response(
        JSON.stringify({ success: false, error: "order_id and amount are required" }),
        { status: 400, headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    const PAYMENT_PROJECT_SLUG = Deno.env.get("PAKASIR_PROJECT_SLUG") || "";
    const PAYMENT_API_KEY = Deno.env.get("PAKASIR_API_KEY") || "";
    const PAYMENT_CALLBACK_URL = `${Deno.env.get("SUPABASE_URL")}/functions/v1/pakasir-webhook`;

    if (!PAYMENT_PROJECT_SLUG || !PAYMENT_API_KEY) {
      console.error("[PAYMENT] Missing credentials");
      return new Response(
        JSON.stringify({ success: false, error: "Payment provider credentials not configured" }),
        { status: 500, headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    console.log("[PAYMENT] Creating payment transaction:", { order_id, amount, method });

    if (method === 'paypal') {
      // Return PayPal payment URL
      const paypalUrl = `https://app.pakasir.com/paypal/${PAYMENT_PROJECT_SLUG}/${amount}?order_id=${order_id}`;

      return new Response(
        JSON.stringify({
          success: true,
          data: {
            payment_url: paypalUrl,
            method: 'paypal',
            order_id: order_id,
          }
        }),
        { headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    // Default: QRIS - Call provider API
    const paymentResponse = await fetch(`https://app.pakasir.com/api/transactioncreate/qris`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        project: PAYMENT_PROJECT_SLUG,
        order_id: order_id,
        amount: amount,
        api_key: PAYMENT_API_KEY,
        description: description || `Order ${order_id}`,
        callback_url: PAYMENT_CALLBACK_URL,
      }),
    });

    if (!paymentResponse.ok) {
      const errorText = await paymentResponse.text();
      console.error("[PAYMENT] Provider API error:", paymentResponse.status, errorText);

      // Fallback: return direct payment URL
      const fallbackUrl = `https://app.pakasir.com/pay/${PAYMENT_PROJECT_SLUG}/${amount}?order_id=${order_id}`;

      return new Response(
        JSON.stringify({
          success: true,
          data: {
            payment_url: fallbackUrl,
            method: 'qris',
            fallback: true,
            order_id: order_id,
          }
        }),
        { headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    const result = await paymentResponse.json();
    console.log("[PAYMENT] Payment created:", result);

    // Return QRIS data for display in app
    return new Response(
      JSON.stringify({
        success: true,
        data: {
          method: 'qris',
          qr_string: result.qr_string || result.qr || null,
          expired_at: result.expired_at || null,
          // Fallback URL if QR code is not available
          payment_url: `https://app.pakasir.com/pay/${PAYMENT_PROJECT_SLUG}/${amount}?order_id=${order_id}`,
          order_id: order_id,
        }
      }),
      { headers: { ...corsHeaders, "Content-Type": "application/json" } }
    );

  } catch (error: any) {
    console.error("[PAYMENT] Unexpected error:", error);
    return new Response(
      JSON.stringify({
        success: false,
        error: error.message || "Internal server error"
      }),
      { status: 500, headers: { ...corsHeaders, "Content-Type": "application/json" } }
    );
  }
});