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 EmailRequest {
  recipient: string;
  subject: string;
  content: string;
}

// Send via Mailketing API
async function sendViaMailketing(
  request: EmailRequest,
  apiToken: string,
  fromName: string,
  fromEmail: string
): Promise<{ success: boolean; message: string }> {
  const { recipient, subject, content } = request;

  // Build form-encoded body (http_build_query format)
  const params = new URLSearchParams();
  params.append('api_token', apiToken);
  params.append('from_name', fromName);
  params.append('from_email', fromEmail);
  params.append('recipient', recipient);
  params.append('subject', subject);
  params.append('content', content);

  console.log(`Sending email via Mailketing to ${recipient}`);

  const response = await fetch('https://api.mailketing.co.id/api/v1/send', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
    },
    body: params.toString(),
  });

  if (!response.ok) {
    const errorText = await response.text();
    console.error('Mailketing API error:', response.status, errorText);
    throw new Error(`Mailketing API error: ${response.status} ${errorText}`);
  }

  const result = await response.json();
  console.log('Mailketing API response:', result);

  return {
    success: true,
    message: result.response || 'Email sent successfully via Mailketing'
  };
}

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

  try {
    // Initialize Supabase client
    const supabaseUrl = Deno.env.get("SUPABASE_URL")!;
    const supabaseServiceKey = Deno.env.get("SUPABASE_SERVICE_ROLE_KEY")!;
    const supabase = createClient(supabaseUrl, supabaseServiceKey);

    // Fetch email settings from platform_settings
    const { data: settings, error: settingsError } = await supabase
      .from('platform_settings')
      .select('*')
      .single();

    if (settingsError || !settings) {
      console.error('Error fetching platform settings:', settingsError);
      throw new Error('Failed to fetch email configuration from platform_settings');
    }

    const apiToken = settings.integration_email_api_token;
    const fromName = settings.integration_email_from_name || settings.brand_name;
    const fromEmail = settings.integration_email_from_email;

    if (!apiToken || !fromEmail) {
      return new Response(
        JSON.stringify({ success: false, message: "Email not configured. Please set API token and from email in platform settings." }),
        { status: 400, headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    const body: EmailRequest = await req.json();

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

    // Basic email validation
    const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
    if (!emailRegex.test(body.recipient) || !emailRegex.test(fromEmail)) {
      return new Response(
        JSON.stringify({ success: false, message: "Invalid email format" }),
        { status: 400, headers: { ...corsHeaders, "Content-Type": "application/json" } }
      );
    }

    console.log(`Attempting to send email to: ${body.recipient}`);
    console.log(`From: ${fromName} <${fromEmail}>`);
    console.log(`Subject: ${body.subject}`);

    const result = await sendViaMailketing(body, apiToken, fromName, fromEmail);

    return new Response(
      JSON.stringify(result),
      { status: 200, headers: { ...corsHeaders, "Content-Type": "application/json" } }
    );

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