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;
}

// Allowed database fields for each entity type
const RIDE_FIELDS = [
  'name', 'slug', 'description', 'park_id', 'ride_model_id', 
  'manufacturer_id', 'designer_id', 'category', 'status',
  'opening_date', 'closing_date', 'height_requirement', 'age_requirement',
  'capacity_per_hour', 'duration_seconds', 'max_speed_kmh', 
  'max_height_meters', 'length_meters', 'inversions',
  'ride_sub_type', 'coaster_type', 'seating_type', 'intensity_level',
  'drop_height_meters', 'max_g_force', 'image_url',
  'banner_image_url', 'banner_image_id', 'card_image_url', 'card_image_id'
];

const PARK_FIELDS = [
  'name', 'slug', 'description', 'park_type', 'status',
  'opening_date', 'closing_date', 'location_id', 'operator_id',
  'property_owner_id', 'website_url', 'phone', 'email',
  'banner_image_url', 'banner_image_id', 'card_image_url', 'card_image_id'
];

const COMPANY_FIELDS = [
  'name', 'slug', 'description', 'company_type', 'person_type',
  'founded_year', 'headquarters_location', 'website_url', 'logo_url',
  'banner_image_url', 'banner_image_id', 'card_image_url', 'card_image_id'
];

const RIDE_MODEL_FIELDS = [
  'name', 'slug', 'description', 'category', 'ride_type',
  'manufacturer_id', 'banner_image_url', 'banner_image_id',
  'card_image_url', 'card_image_id'
];

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();

    // UUID validation regex
    const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;

    // Validate itemIds
    if (!itemIds || !Array.isArray(itemIds)) {
      return new Response(
        JSON.stringify({ error: 'itemIds is required and must be an array' }),
        { status: 400, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
      );
    }

    if (itemIds.length === 0) {
      return new Response(
        JSON.stringify({ error: 'itemIds must be a non-empty array' }),
        { status: 400, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
      );
    }

    // Validate userId
    if (!userId || typeof userId !== 'string' || userId.trim() === '') {
      return new Response(
        JSON.stringify({ error: 'userId is required and must be a non-empty string' }),
        { status: 400, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
      );
    }

    if (!uuidRegex.test(userId)) {
      return new Response(
        JSON.stringify({ error: 'userId must be a valid UUID format' }),
        { status: 400, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
      );
    }

    // Validate submissionId
    if (!submissionId || typeof submissionId !== 'string' || submissionId.trim() === '') {
      return new Response(
        JSON.stringify({ error: 'submissionId is required and must be a non-empty string' }),
        { status: 400, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
      );
    }

    if (!uuidRegex.test(submissionId)) {
      return new Response(
        JSON.stringify({ error: 'submissionId must be a valid UUID format' }),
        { status: 400, headers: { ...corsHeaders, 'Content-Type': 'application/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}`);
    }

    // Get the submitter's user_id from the submission
    const { data: submission, error: submissionError } = await supabase
      .from('content_submissions')
      .select('user_id')
      .eq('id', submissionId)
      .single();

    if (submissionError || !submission) {
      throw new Error(`Failed to fetch submission: ${submissionError?.message}`);
    }

    const submitterId = submission.user_id;

    // Topologically sort items by dependencies
    const sortedItems = topologicalSort(items);
    const dependencyMap = new Map<string, string>();
    const approvalResults: Array<{
  itemId: string;
  entityId?: string | null;
  itemType: string;
  success: boolean;
  error?: string;
}> = [];

    // Process items in order
    for (const item of sortedItems) {
      try {
        console.log(`Processing item ${item.id} of type ${item.item_type}`);
        
        // Set user context for versioning trigger
        // This allows auto_create_entity_version() to capture the submitter
        const { error: setConfigError } = await supabase.rpc('set_config_value', {
          setting_name: 'app.current_user_id',
          setting_value: submitterId,
          is_local: false
        });
        
        if (setConfigError) {
          console.error('Failed to set user context:', setConfigError);
        }
        
        // Resolve dependencies in item data
        const resolvedData = resolveDependencies(item.item_data, dependencyMap);
        
        // Add submitter ID to the data for photo tracking
        resolvedData._submitter_id = submitterId;
        
        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;
          case 'photo_edit':
            await editPhoto(supabase, resolvedData);
            entityId = resolvedData.photo_id;
            break;
          case 'photo_delete':
            await deletePhoto(supabase, resolvedData);
            entityId = resolvedData.photo_id;
            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 instanceof Error ? error.message : 'Unknown error'
        });
      }
    }

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

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

    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 instanceof Error ? error.message : 'Unknown error' }),
      { 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;
}

function sanitizeDateFields(data: any): any {
  const dateFields = ['opening_date', 'closing_date', 'date_changed', 'date_taken', 'visit_date'];
  const sanitized = { ...data };
  
  for (const field of dateFields) {
    if (field in sanitized && sanitized[field] === '') {
      sanitized[field] = null;
    }
  }
  
  return sanitized;
}

function filterDatabaseFields(data: any, allowedFields: string[]): any {
  const filtered: any = {};
  for (const field of allowedFields) {
    if (field in data && data[field] !== undefined) {
      filtered[field] = data[field];
    }
  }
  return filtered;
}

function normalizeStatusValue(data: any): any {
  if (data.status) {
    // Map display values to database values
    const statusMap: Record<string, string> = {
      'Operating': 'operating',
      'Seasonal': 'operating',
      'Closed Temporarily': 'maintenance',
      'Closed Permanently': 'closed',
      'Under Construction': 'under_construction',
      'Planned': 'under_construction',
      'SBNO': 'sbno',
      // Also handle already-lowercase values
      'operating': 'operating',
      'closed': 'closed',
      'under_construction': 'under_construction',
      'maintenance': 'maintenance',
      'sbno': 'sbno'
    };
    
    data.status = statusMap[data.status] || 'operating';
  }
  return data;
}

async function createPark(supabase: any, data: any): Promise<string> {
  const submitterId = data._submitter_id;
  let uploadedPhotos: any[] = [];
  
  // Transform images object if present
  if (data.images) {
    const { uploaded, banner_assignment, card_assignment } = data.images;
    
    if (uploaded && Array.isArray(uploaded)) {
      // Store uploaded photos for later insertion into photos table
      uploadedPhotos = uploaded;
      
      // Assign banner image
      if (banner_assignment !== undefined && uploaded[banner_assignment]) {
        data.banner_image_id = uploaded[banner_assignment].cloudflare_id;
        data.banner_image_url = uploaded[banner_assignment].url;
      }
      
      // Assign card image
      if (card_assignment !== undefined && uploaded[card_assignment]) {
        data.card_image_id = uploaded[card_assignment].cloudflare_id;
        data.card_image_url = uploaded[card_assignment].url;
      }
    }
    
    // Remove images object
    delete data.images;
  }

  // Remove internal fields
  delete data._submitter_id;

  let parkId: string;

  // Check if this is an edit (has park_id) or a new creation
  if (data.park_id) {
    console.log(`Updating existing park ${data.park_id}`);
    parkId = data.park_id;
    delete data.park_id; // Remove ID from update data
    
    const normalizedData = normalizeStatusValue(data);
    const sanitizedData = sanitizeDateFields(normalizedData);
    const filteredData = filterDatabaseFields(sanitizedData, PARK_FIELDS);
    const { error } = await supabase
      .from('parks')
      .update(filteredData)
      .eq('id', parkId);

    if (error) throw new Error(`Failed to update park: ${error.message}`);
  } else {
    console.log('Creating new park');
    const normalizedData = normalizeStatusValue(data);
    const sanitizedData = sanitizeDateFields(normalizedData);
    const filteredData = filterDatabaseFields(sanitizedData, PARK_FIELDS);
    const { data: park, error } = await supabase
      .from('parks')
      .insert(filteredData)
      .select('id')
      .single();

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

  // Insert photos into photos table
  if (uploadedPhotos.length > 0 && submitterId) {
    console.log(`Inserting ${uploadedPhotos.length} photos for park ${parkId}`);
    for (let i = 0; i < uploadedPhotos.length; i++) {
      const photo = uploadedPhotos[i];
      if (photo.cloudflare_id && photo.url) {
        const { error: photoError } = await supabase.from('photos').insert({
          entity_id: parkId,
          entity_type: 'park',
          cloudflare_image_id: photo.cloudflare_id,
          cloudflare_image_url: photo.url,
          caption: photo.caption || null,
          title: null,
          submitted_by: submitterId,
          approved_at: new Date().toISOString(),
          order_index: i,
        });

        if (photoError) {
          console.error(`Failed to insert photo ${i}:`, photoError);
        }
      }
    }
  }

  return parkId;
}

async function createRide(supabase: any, data: any): Promise<string> {
  const submitterId = data._submitter_id;
  let uploadedPhotos: any[] = [];
  
  // Transform images object if present
  if (data.images) {
    const { uploaded, banner_assignment, card_assignment } = data.images;
    
    if (uploaded && Array.isArray(uploaded)) {
      // Store uploaded photos for later insertion into photos table
      uploadedPhotos = uploaded;
      
      // Assign banner image
      if (banner_assignment !== undefined && uploaded[banner_assignment]) {
        data.banner_image_id = uploaded[banner_assignment].cloudflare_id;
        data.banner_image_url = uploaded[banner_assignment].url;
      }
      
      // Assign card image
      if (card_assignment !== undefined && uploaded[card_assignment]) {
        data.card_image_id = uploaded[card_assignment].cloudflare_id;
        data.card_image_url = uploaded[card_assignment].url;
      }
    }
    
    // Remove images object
    delete data.images;
  }

  // Remove internal fields and store park_id before filtering
  delete data._submitter_id;
  const parkId = data.park_id;

  let rideId: string;

  // Check if this is an edit (has ride_id) or a new creation
  if (data.ride_id) {
    console.log(`Updating existing ride ${data.ride_id}`);
    rideId = data.ride_id;
    delete data.ride_id; // Remove ID from update data
    
    const normalizedData = normalizeStatusValue(data);
    const sanitizedData = sanitizeDateFields(normalizedData);
    const filteredData = filterDatabaseFields(sanitizedData, RIDE_FIELDS);
    const { error } = await supabase
      .from('rides')
      .update(filteredData)
      .eq('id', rideId);

    if (error) throw new Error(`Failed to update ride: ${error.message}`);
    
    // Update park ride counts after successful ride update
    if (parkId) {
      console.log(`Updating ride counts for park ${parkId}`);
      const { error: countError } = await supabase.rpc('update_park_ride_counts', {
        target_park_id: parkId
      });
      
      if (countError) {
        console.error('Failed to update park counts:', countError);
      }
    }
  } else {
    console.log('Creating new ride');
    const normalizedData = normalizeStatusValue(data);
    const sanitizedData = sanitizeDateFields(normalizedData);
    const filteredData = filterDatabaseFields(sanitizedData, RIDE_FIELDS);
    const { data: ride, error } = await supabase
      .from('rides')
      .insert(filteredData)
      .select('id')
      .single();

    if (error) throw new Error(`Failed to create ride: ${error.message}`);
    rideId = ride.id;
    
    // Update park ride counts after successful ride creation
    if (parkId) {
      console.log(`Updating ride counts for park ${parkId}`);
      const { error: countError } = await supabase.rpc('update_park_ride_counts', {
        target_park_id: parkId
      });
      
      if (countError) {
        console.error('Failed to update park counts:', countError);
      }
    }
  }

  // Insert photos into photos table
  if (uploadedPhotos.length > 0 && submitterId) {
    console.log(`Inserting ${uploadedPhotos.length} photos for ride ${rideId}`);
    for (let i = 0; i < uploadedPhotos.length; i++) {
      const photo = uploadedPhotos[i];
      if (photo.cloudflare_id && photo.url) {
        const { error: photoError } = await supabase.from('photos').insert({
          entity_id: rideId,
          entity_type: 'ride',
          cloudflare_image_id: photo.cloudflare_id,
          cloudflare_image_url: photo.url,
          caption: photo.caption || null,
          title: null,
          submitted_by: submitterId,
          approved_at: new Date().toISOString(),
          order_index: i,
        });

        if (photoError) {
          console.error(`Failed to insert photo ${i}:`, photoError);
        }
      }
    }
  }

  return rideId;
}

async function createCompany(supabase: any, data: any, companyType: string): Promise<string> {
  // Transform images object if present
  if (data.images) {
    const { uploaded, banner_assignment, card_assignment } = data.images;
    
    if (uploaded && Array.isArray(uploaded)) {
      // Assign banner image
      if (banner_assignment !== undefined && uploaded[banner_assignment]) {
        data.banner_image_id = uploaded[banner_assignment].cloudflare_id;
        data.banner_image_url = uploaded[banner_assignment].url;
      }
      
      // Assign card image
      if (card_assignment !== undefined && uploaded[card_assignment]) {
        data.card_image_id = uploaded[card_assignment].cloudflare_id;
        data.card_image_url = uploaded[card_assignment].url;
      }
    }
    
    // Remove images object
    delete data.images;
  }

  // Check if this is an edit (has company_id or id) or a new creation
  const companyId = data.company_id || data.id;
  
  if (companyId) {
    console.log(`Updating existing company ${companyId}`);
    const updateData = sanitizeDateFields({ ...data, company_type: companyType });
    delete updateData.company_id;
    delete updateData.id; // Remove ID from update data
    const filteredData = filterDatabaseFields(updateData, COMPANY_FIELDS);
    
    const { error } = await supabase
      .from('companies')
      .update(filteredData)
      .eq('id', companyId);

    if (error) throw new Error(`Failed to update company: ${error.message}`);
    return companyId;
  } else {
    console.log('Creating new company');
    const companyData = sanitizeDateFields({ ...data, company_type: companyType });
    const filteredData = filterDatabaseFields(companyData, COMPANY_FIELDS);
    const { data: company, error } = await supabase
      .from('companies')
      .insert(filteredData)
      .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 sanitizedData = sanitizeDateFields(data);
  const filteredData = filterDatabaseFields(sanitizedData, RIDE_MODEL_FIELDS);
  const { data: model, error } = await supabase
    .from('ride_models')
    .insert(filteredData)
    .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;
}

async function editPhoto(supabase: any, data: any): Promise<void> {
  console.log(`Editing photo ${data.photo_id}`);
  const { error } = await supabase
    .from('photos')
    .update({
      caption: data.new_caption,
    })
    .eq('id', data.photo_id);

  if (error) throw new Error(`Failed to edit photo: ${error.message}`);
}

async function deletePhoto(supabase: any, data: any): Promise<void> {
  console.log(`Deleting photo ${data.photo_id}`);
  const { error } = await supabase
    .from('photos')
    .delete()
    .eq('id', data.photo_id);

  if (error) throw new Error(`Failed to delete photo: ${error.message}`);
}