import { serve } from "https://deno.land/std@0.190.0/http/server.ts";
import { createClient } from "https://esm.sh/@supabase/supabase-js@2";

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

interface SendOTPRequest {
  user_id: string;
  email: string;
}

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

  try {
    const { user_id, email }: SendOTPRequest = await req.json();

    // Validate required fields
    if (!user_id || !email) {
      return new Response(
        JSON.stringify({ success: false, message: "Missing required fields: user_id, email" }),
        { status: 400, headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    // Initialize Supabase client with service role
    const supabaseUrl = Deno.env.get('SUPABASE_URL')!;
    const supabaseServiceKey = Deno.env.get('SUPABASE_SERVICE_ROLE_KEY')!;
    const supabase = createClient(supabaseUrl, supabaseServiceKey);

    // Fetch platform settings for brand name and URL
    const { data: platformSettings } = await supabase
      .from('platform_settings')
      .select('brand_name, platform_url')
      .single();

    const platformName = platformSettings?.brand_name || 'ACCESS HUB';
    const platformUrl = platformSettings?.platform_url || 'https://access-hub.com';

    console.log(`Generating OTP for user ${user_id}`);

    // Generate 6-digit OTP code
    const otpCode = Math.floor(100000 + Math.random() * 900000).toString();

    // Calculate expiration time (15 minutes from now)
    const expiresAt = new Date(Date.now() + 15 * 60 * 1000).toISOString();

    // Store OTP in database
    const { error: insertError } = await supabase
      .from('auth_otps')
      .insert({
        user_id: user_id,
        email: email,
        otp_code: otpCode,
        expires_at: expiresAt,
      });

    if (insertError) {
      console.error('Error storing OTP:', insertError);
      throw new Error(`Failed to store OTP: ${insertError.message}`);
    }

    console.log(`OTP generated and stored: ${otpCode}, expires at: ${expiresAt}`);

    // Send OTP email using send-notification
    const notificationUrl = `${supabaseUrl}/functions/v1/send-notification`;
    const notificationResponse = await fetch(notificationUrl, {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${supabaseServiceKey}`,
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        template_key: 'auth_email_verification',
        recipient_email: email,
        recipient_name: email.split('@')[0],
        variables: {
          nama: email.split('@')[0],
          otp_code: otpCode,
          email: email,
          user_id: user_id,
          expiry_minutes: '15',
          platform_name: platformName,
          platform_url: platformUrl
        }
      }),
    });

    if (!notificationResponse.ok) {
      const errorText = await notificationResponse.text();
      console.error('Error sending notification email:', notificationResponse.status, errorText);
      throw new Error(`Failed to send OTP email: ${notificationResponse.status} ${errorText}`);
    }

    const notificationResult = await notificationResponse.json();
    console.log('Notification sent successfully:', notificationResult);

    return new Response(
      JSON.stringify({
        success: true,
        message: "OTP sent successfully"
      }),
      { status: 200, headers: { ...corsHeaders, "Content-Type": "application/json" } }
    );

  } catch (error: any) {
    console.error("Error sending OTP:", error);
    return new Response(
      JSON.stringify({
        success: false,
        message: error.message || "Failed to send OTP"
      }),
      { status: 500, headers: { ...corsHeaders, "Content-Type": "application/json" } }
    );
  }
});