import { prisma, withTransaction } from './prisma';
import { Item} from '../types/database';
import { v4 as uuidv4 } from 'uuid';
import { Prisma } from '../generated/prisma';

// Type for transaction client
type TransactionClient = Prisma.TransactionClient;

// Insert URL
export async function insertUrl(url: string): Promise<number> {
  console.log(`[DB] Inserting URL: ${url}`);
  
  const result = await prisma.url.upsert({
    where: { url },
    update: {},
    create: { url },
  });
  
  console.log(`[DB] URL inserted/found with ID: ${result.id}`);
  return result.id;
}

// Get or create property
async function getOrCreateProperty(tx: TransactionClient, propertyName: string): Promise<number> {
  const existing = await tx.property.findUnique({
    where: { name: propertyName }
  });
  
  if (existing) {
    return existing.id;
  }
  
  const created = await tx.property.create({
    data: { name: propertyName, globalUsageCount: 0 }
  });
  
  return created.id;
}

// Get items by URL
export async function getItemsByUrl(url: string): Promise<Item[]> {
  console.log(`[DB] Getting items for URL: ${url}`);
  
  return await withTransaction(async (tx) => {
    // Get URL record
    const urlRecord = await tx.url.findUnique({
      where: { url },
      include: {
        items: {
          orderBy: { itemOrder: 'asc' },
          include: {
            // We don't include itemProperties here since we'll fetch them by globalItemId
          }
        }
      }
    });
    
    if (!urlRecord) {
      console.log(`[DB] No URL record found for: ${url}`);
      return [];
    }
    
    console.log(`[DB] Found ${urlRecord.items.length} items for URL: ${url}`);
    
    // For each item, get properties from globalItemId
    const items: Item[] = [];
    
    for (const dbItem of urlRecord.items) {
      // Get all properties for this globalItemId
      const itemProperties = await tx.itemProperty.findMany({
        where: { globalItemId: dbItem.globalItemId },
        include: { property: true }
      });
      
      // Separate core properties from custom properties
      const customProperties: Record<string, string> = {};
      let name = '';
      let description = '';
      
      for (const prop of itemProperties) {
        const propName = prop.property.name;
        const propValue = prop.value;
        
        if (propName === 'name') {
          name = propValue;
        } else if (propName === 'description') {
          description = propValue;
        } else {
          customProperties[propName] = propValue;
        }
      }
      
      const item: Item = {
        id: dbItem.id,
        name,
        description,
        wikidataId: dbItem.wikidataId || undefined,
        customProperties
      };
      
      items.push(item);
    }
    
    console.log(`[DB] Returning ${items.length} items with properties`);
    return items;
  });
}

// Insert item by URL
export async function insertItemByUrl(url: string, item: Item): Promise<void> {
  console.log(`[DB] Starting insert for URL: ${url}, Item: ${item.id}, Name: ${item.name}`);
  
  await withTransaction(async (tx) => {
    // 1. Get or create URL
    const urlRecord = await tx.url.upsert({
      where: { url },
      update: {},
      create: { url },
    });
    
    console.log(`[DB] URL ID: ${urlRecord.id}`);
    
    // 2. Check if this specific item already exists for this URL
    const existingItem = await tx.item.findUnique({
      where: { id: item.id }
    });
    
    // 3. Find or create globalItemId based on item name
    let globalItemId: string;
    
    if (existingItem) {
      // Use existing globalItemId if item already exists
      globalItemId = existingItem.globalItemId;
      console.log(`[DB] Using existing global item ID: ${globalItemId}`);
    } else {
      // For new items, find existing globalItemId by name or create new one
      const namePropertyId = await getOrCreateProperty(tx, 'name');
      
      // Look for existing global item with the same name
      const existingGlobalItem = await tx.itemProperty.findFirst({
        where: {
          propertyId: namePropertyId,
          value: item.name.trim()
        },
        select: { globalItemId: true }
      });
      
      if (existingGlobalItem && item.name.trim()) {
        // Use existing globalItemId for items with the same name
        globalItemId = existingGlobalItem.globalItemId;
        console.log(`[DB] Found existing global item ID for name "${item.name}": ${globalItemId}`);
      } else {
        // Create new globalItemId for new names or empty names
        globalItemId = uuidv4();
        console.log(`[DB] Created new global item ID: ${globalItemId}`);
      }
    }
    
    // 4. Get max order for new items
    const maxOrder = await tx.item.findFirst({
      where: { urlId: urlRecord.id },
      orderBy: { itemOrder: 'desc' },
      select: { itemOrder: true }
    });
    
    // 5. Upsert the item record (unique by item.id)
    await tx.item.upsert({
      where: { id: item.id },
      update: {
        urlId: urlRecord.id,
        wikidataId: item.wikidataId,
        globalItemId
      },
      create: {
        id: item.id,
        urlId: urlRecord.id,
        wikidataId: item.wikidataId,
        itemOrder: (maxOrder?.itemOrder || 0) + 1,
        globalItemId
      }
    });
    
    // 6. Handle all properties (core + custom)
    const allProperties = [
      ['name', item.name],
      ['description', item.description],
      ...Object.entries(item.customProperties)
    ];
    
    for (const [propName, propValue] of allProperties) {
      const propertyId = await getOrCreateProperty(tx, propName);
      
      // Update properties for the globalItemId (this affects all items with same name)
      await tx.itemProperty.upsert({
        where: {
          globalItemId_propertyId: {
            globalItemId,
            propertyId
          }
        },
        update: { value: propValue },
        create: {
          globalItemId,
          propertyId,
          value: propValue
        }
      });
    }
    
    console.log(`[DB] Item ${item.id} with global ID ${globalItemId} inserted/updated successfully`);
  });
}

// Delete item by URL
export async function deleteItemByUrl(url: string, itemId: string): Promise<void> {
  console.log(`[DB] Deleting item ${itemId} from URL: ${url}`);
  
  await withTransaction(async (tx) => {
    // Get URL ID
    const urlRecord = await tx.url.findUnique({
      where: { url }
    });
    
    if (!urlRecord) {
      throw new Error(`URL not found: ${url}`);
    }
    
    // Get the item to find its global_item_id
    const item = await tx.item.findFirst({
      where: { id: itemId, urlId: urlRecord.id }
    });
    
    if (!item) {
      throw new Error(`Item not found: ${itemId}`);
    }
    
    // Delete the item (this will cascade to item_properties via foreign key)
    await tx.item.delete({
      where: { id: itemId }
    });
    
    // Clean up item properties for this global item
    await tx.itemProperty.deleteMany({
      where: { globalItemId: item.globalItemId }
    });
    
    console.log(`[DB] Item ${itemId} deleted successfully`);
  });
}

// Delete property by URL
export async function deletePropertyByUrl(url: string, propertyName: string): Promise<void> {
  console.log(`[DB] Starting soft delete of property ${propertyName} for URL: ${url}`);
  
  await withTransaction(async (tx) => {
    // Get URL ID
    const urlRecord = await tx.url.findUnique({
      where: { url }
    });
    
    if (!urlRecord) {
      console.error(`[DB] URL not found: ${url}`);
      throw new Error(`URL not found: ${url}`);
    }
    
    console.log(`[DB] Found URL record with ID: ${urlRecord.id}`);
    
    // Get property ID
    const property = await tx.property.findUnique({
      where: { name: propertyName }
    });
    
    if (!property) {
      console.error(`[DB] Property not found: ${propertyName}`);
      throw new Error(`Property not found: ${propertyName}`);
    }
    
    console.log(`[DB] Found property record with ID: ${property.id}`);
    
    // Remove from selected properties first
    const deletedSelectedProperties = await tx.selectedProperty.deleteMany({
      where: {
        urlId: urlRecord.id,
        propertyId: property.id
      }
    });
    
    console.log(`[DB] Removed ${deletedSelectedProperties.count} selected property records`);
    
    // Get all global item IDs for this URL
    const items = await tx.item.findMany({
      where: { urlId: urlRecord.id },
      select: { globalItemId: true }
    });
    
    console.log(`[DB] Found ${items.length} items for URL`);
    
    // Insert into deleted_properties for each global item
    let deletedPropertiesCount = 0;
    for (const item of items) {
      await tx.deletedProperty.upsert({
        where: {
          urlId_globalItemId_propertyId: {
            urlId: urlRecord.id,
            globalItemId: item.globalItemId,
            propertyId: property.id
          }
        },
        update: {},
        create: {
          urlId: urlRecord.id,
          globalItemId: item.globalItemId,
          propertyId: property.id
        }
      });
      deletedPropertiesCount++;
    }
    
    console.log(`[DB] Created/updated ${deletedPropertiesCount} deleted property records`);
    console.log(`[DB] Successfully soft deleted property ${propertyName} for URL: ${url}`);
  });
}

// Add selected property
export async function addSelectedProperty(url: string, propertyName: string): Promise<void> {
  console.log(`[DB] Adding selected property ${propertyName} for URL: ${url}`);
  
  await withTransaction(async (tx) => {
    // Get or create URL
    const urlRecord = await tx.url.upsert({
      where: { url },
      update: {},
      create: { url }
    });
    
    // Get or create property
    const propertyId = await getOrCreateProperty(tx, propertyName);
    
    // Add to selected properties
    await tx.selectedProperty.upsert({
      where: {
        urlId_propertyId: {
          urlId: urlRecord.id,
          propertyId
        }
      },
      update: {},
      create: {
        urlId: urlRecord.id,
        propertyId
      }
    });
    
    console.log(`[DB] Selected property ${propertyName} added for URL: ${url}`);
  });
}

// Get selected properties
export async function getSelectedProperties(url: string): Promise<string[]> {
  console.log(`[DB] Getting selected properties for URL: ${url}`);
  
  const result = await prisma.selectedProperty.findMany({
    where: {
      url: { url }
    },
    include: {
      property: true
    }
  });
  
  const properties = result.map(sp => sp.property.name);
  console.log(`[DB] Found ${properties.length} selected properties`);
  return properties;
}