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

interface ApprovalRequest {
  itemIds: string[];
  userId: string;
  submissionId: string;
}

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

  try {
    const supabase = createClient(
      Deno.env.get('SUPABASE_URL') ?? '',
      Deno.env.get('SUPABASE_SERVICE_ROLE_KEY') ?? ''
    );

    const { itemIds, userId, submissionId }: ApprovalRequest = await req.json();

    console.log('Processing selective approval:', { itemIds, userId, submissionId });

    // Fetch all items for the submission
    const { data: items, error: fetchError } = await supabase
      .from('submission_items')
      .select('*')
      .in('id', itemIds);

    if (fetchError) {
      throw new Error(`Failed to fetch items: ${fetchError.message}`);
    }

    // Topologically sort items by dependencies
    const sortedItems = topologicalSort(items);
    const dependencyMap = new Map<string, string>();
    const approvalResults = [];

    // Process items in order
    for (const item of sortedItems) {
      try {
        console.log(`Processing item ${item.id} of type ${item.item_type}`);
        
        // Resolve dependencies in item data
        const resolvedData = resolveDependencies(item.item_data, dependencyMap);
        
        let entityId: string | null = null;

        // Create entity based on type
        switch (item.item_type) {
          case 'park':
            entityId = await createPark(supabase, resolvedData);
            break;
          case 'ride':
            entityId = await createRide(supabase, resolvedData);
            break;
          case 'manufacturer':
          case 'operator':
          case 'property_owner':
          case 'designer':
            entityId = await createCompany(supabase, resolvedData, item.item_type);
            break;
          case 'ride_model':
            entityId = await createRideModel(supabase, resolvedData);
            break;
          case 'photo':
            await approvePhotos(supabase, resolvedData, item.id);
            entityId = item.id; // Use item ID as entity ID for photos
            break;
          default:
            throw new Error(`Unknown item type: ${item.item_type}`);
        }

        if (entityId) {
          dependencyMap.set(item.id, entityId);
        }

        // Update item status
        const { error: updateError } = await supabase
          .from('submission_items')
          .update({
            status: 'approved',
            approved_entity_id: entityId,
            updated_at: new Date().toISOString()
          })
          .eq('id', item.id);

        if (updateError) {
          throw new Error(`Failed to update item status: ${updateError.message}`);
        }

        approvalResults.push({
          itemId: item.id,
          entityId,
          itemType: item.item_type,
          success: true
        });

        console.log(`Successfully approved item ${item.id} -> entity ${entityId}`);
      } catch (error) {
        console.error(`Error processing item ${item.id}:`, error);
        approvalResults.push({
          itemId: item.id,
          itemType: item.item_type,
          success: false,
          error: error.message
        });
      }
    }

    // Update submission status
    const allApproved = approvalResults.every(r => r.success);
    const { error: submissionError } = await supabase
      .from('content_submissions')
      .update({
        status: allApproved ? 'approved' : 'partially_approved',
        reviewer_id: userId,
        reviewed_at: new Date().toISOString()
      })
      .eq('id', submissionId);

    if (submissionError) {
      console.error('Failed to update submission status:', submissionError);
    }

    return new Response(
      JSON.stringify({
        success: true,
        results: approvalResults,
        submissionStatus: allApproved ? 'approved' : 'partially_approved'
      }),
      { headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
    );
  } catch (error) {
    console.error('Error in process-selective-approval:', error);
    return new Response(
      JSON.stringify({ error: error.message }),
      { status: 500, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
    );
  }
});

// Helper functions
function topologicalSort(items: any[]): any[] {
  const sorted: any[] = [];
  const visited = new Set<string>();
  const visiting = new Set<string>();

  const visit = (item: any) => {
    if (visited.has(item.id)) return;
    if (visiting.has(item.id)) {
      throw new Error(`Circular dependency detected for item ${item.id}`);
    }

    visiting.add(item.id);

    if (item.depends_on) {
      const parent = items.find(i => i.id === item.depends_on);
      if (parent) {
        visit(parent);
      }
    }

    visiting.delete(item.id);
    visited.add(item.id);
    sorted.push(item);
  };

  items.forEach(item => visit(item));
  return sorted;
}

function resolveDependencies(data: any, dependencyMap: Map<string, string>): any {
  if (typeof data !== 'object' || data === null) {
    return data;
  }

  if (Array.isArray(data)) {
    return data.map(item => resolveDependencies(item, dependencyMap));
  }

  const resolved: any = {};
  for (const [key, value] of Object.entries(data)) {
    if (typeof value === 'string' && dependencyMap.has(value)) {
      resolved[key] = dependencyMap.get(value);
    } else {
      resolved[key] = resolveDependencies(value, dependencyMap);
    }
  }
  return resolved;
}

async function createPark(supabase: any, data: any): Promise<string> {
  const { data: park, error } = await supabase
    .from('parks')
    .insert(data)
    .select('id')
    .single();

  if (error) throw new Error(`Failed to create park: ${error.message}`);
  return park.id;
}

async function createRide(supabase: any, data: any): Promise<string> {
  const { data: ride, error } = await supabase
    .from('rides')
    .insert(data)
    .select('id')
    .single();

  if (error) throw new Error(`Failed to create ride: ${error.message}`);
  return ride.id;
}

async function createCompany(supabase: any, data: any, companyType: string): Promise<string> {
  const companyData = { ...data, company_type: companyType };
  const { data: company, error } = await supabase
    .from('companies')
    .insert(companyData)
    .select('id')
    .single();

  if (error) throw new Error(`Failed to create company: ${error.message}`);
  return company.id;
}

async function createRideModel(supabase: any, data: any): Promise<string> {
  const { data: model, error } = await supabase
    .from('ride_models')
    .insert(data)
    .select('id')
    .single();

  if (error) throw new Error(`Failed to create ride model: ${error.message}`);
  return model.id;
}

async function approvePhotos(supabase: any, data: any, submissionItemId: string): Promise<void> {
  const photos = data.photos || [];
  
  for (const photo of photos) {
    const photoData = {
      entity_id: data.entity_id,
      entity_type: data.context,
      cloudflare_image_id: extractImageId(photo.url),
      cloudflare_image_url: photo.url,
      title: photo.title,
      caption: photo.caption,
      date_taken: photo.date,
      order_index: photo.order,
      submission_id: submissionItemId
    };

    const { error } = await supabase.from('photos').insert(photoData);
    if (error) {
      console.error('Failed to insert photo:', error);
      throw new Error(`Failed to insert photo: ${error.message}`);
    }
  }
}

function extractImageId(url: string): string {
  const matches = url.match(/\/([^\/]+)\/public$/);
  return matches ? matches[1] : url;
}