import { serve } from "https://deno.land/std@0.168.0/http/server.ts";
import { Novu } from "npm:@novu/node@2.0.2";
import { createClient } from "https://esm.sh/@supabase/supabase-js@2.57.4";

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

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

  try {
    const novuApiKey = Deno.env.get('NOVU_API_KEY');
    const supabaseUrl = Deno.env.get('SUPABASE_URL')!;
    const supabaseServiceKey = Deno.env.get('SUPABASE_SERVICE_ROLE_KEY')!;

    if (!novuApiKey) {
      throw new Error('NOVU_API_KEY is not configured');
    }

    const novu = new Novu(novuApiKey, {
      backendUrl: Deno.env.get('VITE_NOVU_API_URL') || 'https://api.novu.co',
    });

    const supabase = createClient(supabaseUrl, supabaseServiceKey);

    const { userId, preferences } = await req.json();

    console.log('Updating preferences for user:', userId);

    // Get Novu subscriber ID from database
    const { data: prefData, error: prefError } = await supabase
      .from('user_notification_preferences')
      .select('novu_subscriber_id')
      .eq('user_id', userId)
      .single();

    if (prefError || !prefData?.novu_subscriber_id) {
      throw new Error('Novu subscriber not found');
    }

    const subscriberId = prefData.novu_subscriber_id;

    // Update channel preferences in Novu
    // Note: Novu's updatePreference updates one channel at a time for a specific workflow
    const channelPrefs = preferences.channelPreferences;
    const workflowId = preferences.workflowId || 'default';
    
    try {
      // Update each channel preference separately
      const channelTypes = ['email', 'sms', 'in_app', 'push'] as const;
      
      for (const channelType of channelTypes) {
        if (channelPrefs[channelType] !== undefined) {
          try {
            await novu.subscribers.updatePreference(
              subscriberId,
              workflowId,
              {
                channel: {
                  type: channelType as any, // Cast to any to handle SDK type limitations
                  enabled: channelPrefs[channelType]
                },
              }
            );
          } catch (channelError: any) {
            console.warn(`Failed to update ${channelType} preference:`, channelError.message);
            // Continue with other channels even if one fails
          }
        }
      }
      console.log('Preferences updated successfully');
    } catch (novuError: any) {
      console.error('Novu API error:', novuError);
      throw new Error(`Failed to update Novu preferences: ${novuError.message || 'Unknown error'}`);
    }

    return new Response(
      JSON.stringify({
        success: true,
      }),
      {
        headers: { ...corsHeaders, 'Content-Type': 'application/json' },
        status: 200,
      }
    );
  } catch (error: any) {
    console.error('Error updating Novu preferences:', error);
    
    return new Response(
      JSON.stringify({
        success: false,
        error: error.message,
      }),
      {
        headers: { ...corsHeaders, 'Content-Type': 'application/json' },
        status: 500,
      }
    );
  }
});