#!/usr/bin/env node

require('dotenv').config({ path: '.env.local' });
const AWS = require('aws-sdk');
const { v4: uuidv4 } = require('uuid');

// Configure AWS
AWS.config.update({
  region: process.env.AWS_REGION || 'eu-central-1'
});

const dynamodb = new AWS.DynamoDB.DocumentClient();
const TABLE_NAME = process.env.DYNAMODB_TABLE_NAME || 'filamenteka-filaments';

// Color mappings for common filament colors
const colorMappings = {
  'Black': '#000000',
  'White': '#FFFFFF',
  'Red': '#FF0000',
  'Blue': '#0000FF',
  'Green': '#00FF00',
  'Yellow': '#FFFF00',
  'Orange': '#FFA500',
  'Purple': '#800080',
  'Gray': '#808080',
  'Grey': '#808080',
  'Silver': '#C0C0C0',
  'Gold': '#FFD700',
  'Brown': '#964B00',
  'Pink': '#FFC0CB',
  'Cyan': '#00FFFF',
  'Magenta': '#FF00FF',
  'Beige': '#F5F5DC',
  'Transparent': '#FFFFFF00',
  // Specific Bambu Lab colors
  'Mistletoe Green': '#50C878',
  'Indingo Purple': '#4B0082',
  'Jade White': '#F0F8FF',
  'Hot Pink': '#FF69B4',
  'Cocoa Brown': '#D2691E',
  'Cotton Candy Cloud': '#FFB6C1',
  'Sunflower Yellow': '#FFDA03',
  'Scarlet Red': '#FF2400',
  'Mandarin Orange': '#FF8C00',
  'Marine Blue': '#0066CC',
  'Charcoal': '#36454F',
  'Ivory White': '#FFFFF0',
  'Ash Gray': '#B2BEB5',
  'Cobalt Blue': '#0047AB',
  'Turquoise': '#40E0D0',
  'Nardo Gray': '#4A4A4A',
  'Bright Green': '#66FF00',
  'Glow Green': '#90EE90',
  'Black Walnut': '#5C4033',
  'Jeans Blue': '#5670A1',
  'Forest Green': '#228B22',
  'Lavender Purple': '#B57EDC'
};

function getColorHex(colorName) {
  // Try exact match first
  if (colorMappings[colorName]) {
    return colorMappings[colorName];
  }
  
  // Try to find color in the name
  for (const [key, value] of Object.entries(colorMappings)) {
    if (colorName.toLowerCase().includes(key.toLowerCase())) {
      return value;
    }
  }
  
  return null;
}

function parseInventory(oldFilament) {
  let total = 1;
  let vacuum = 0;
  let opened = 0;
  
  // Parse kolicina (quantity)
  if (oldFilament.kolicina) {
    const qty = parseInt(oldFilament.kolicina);
    if (!isNaN(qty)) {
      total = qty;
    }
  }
  
  // Parse vakum field
  if (oldFilament.vakum) {
    const vakumLower = oldFilament.vakum.toLowerCase();
    if (vakumLower.includes('vakuum') || vakumLower.includes('vakum')) {
      // Check for multiplier
      const match = vakumLower.match(/x(\d+)/);
      vacuum = match ? parseInt(match[1]) : 1;
    }
  }
  
  // Parse otvoreno field
  if (oldFilament.otvoreno) {
    const otvorenoLower = oldFilament.otvoreno.toLowerCase();
    if (otvorenoLower.includes('otvorena') || otvorenoLower.includes('otvoreno')) {
      // Check for multiplier
      const match = otvorenoLower.match(/(\d+)x/);
      if (match) {
        opened = parseInt(match[1]);
      } else {
        const match2 = otvorenoLower.match(/x(\d+)/);
        opened = match2 ? parseInt(match2[1]) : 1;
      }
    }
  }
  
  // Calculate available
  const available = vacuum + opened;
  const inUse = Math.max(0, total - available);
  
  return {
    total: total || 1,
    available: available,
    inUse: inUse,
    locations: {
      vacuum: vacuum,
      opened: opened,
      printer: 0
    }
  };
}

function determineStorageCondition(oldFilament) {
  if (oldFilament.vakum && oldFilament.vakum.toLowerCase().includes('vakuum')) {
    return 'vacuum';
  }
  if (oldFilament.otvoreno && oldFilament.otvoreno.toLowerCase().includes('otvorena')) {
    return 'opened';
  }
  return 'sealed';
}

function parseMaterial(oldFilament) {
  const base = oldFilament.tip || 'PLA';
  let modifier = null;
  
  if (oldFilament.finish && oldFilament.finish !== 'Basic' && oldFilament.finish !== '') {
    modifier = oldFilament.finish;
  }
  
  // Handle special PLA types
  if (base === 'PLA' && modifier) {
    // These are actually base materials, not modifiers
    if (modifier === 'PETG' || modifier === 'ABS' || modifier === 'TPU') {
      return { base: modifier, modifier: null };
    }
  }
  
  return { base, modifier };
}

function generateSKU(brand, material, color) {
  const brandCode = brand.substring(0, 3).toUpperCase();
  const materialCode = material.base.substring(0, 3);
  const colorCode = color.name.substring(0, 3).toUpperCase();
  const random = Math.random().toString(36).substring(2, 5).toUpperCase();
  return `${brandCode}-${materialCode}-${colorCode}-${random}`;
}

function migrateFilament(oldFilament) {
  const material = parseMaterial(oldFilament);
  const inventory = parseInventory(oldFilament);
  const colorHex = getColorHex(oldFilament.boja);
  
  const newFilament = {
    // Keep existing fields
    id: oldFilament.id || uuidv4(),
    sku: generateSKU(oldFilament.brand, material, { name: oldFilament.boja }),
    
    // Product info
    brand: oldFilament.brand,
    type: oldFilament.tip || 'PLA',
    material: material,
    color: {
      name: oldFilament.boja || 'Unknown',
      hex: colorHex
    },
    
    // Physical properties
    weight: {
      value: 1000, // Default to 1kg
      unit: 'g'
    },
    diameter: 1.75, // Standard diameter
    
    // Inventory
    inventory: inventory,
    
    // Pricing
    pricing: {
      purchasePrice: oldFilament.cena ? parseFloat(oldFilament.cena) : null,
      currency: 'RSD',
      supplier: null,
      purchaseDate: null
    },
    
    // Condition
    condition: {
      isRefill: oldFilament.refill === 'Da',
      openedDate: oldFilament.otvoreno ? new Date().toISOString() : null,
      expiryDate: null,
      storageCondition: determineStorageCondition(oldFilament),
      humidity: null
    },
    
    // Metadata
    tags: [],
    notes: null,
    images: [],
    
    // Timestamps
    createdAt: oldFilament.createdAt || new Date().toISOString(),
    updatedAt: new Date().toISOString(),
    lastUsed: null,
    
    // Keep old structure temporarily for backwards compatibility
    _legacy: {
      tip: oldFilament.tip,
      finish: oldFilament.finish,
      boja: oldFilament.boja,
      refill: oldFilament.refill,
      vakum: oldFilament.vakum,
      otvoreno: oldFilament.otvoreno,
      kolicina: oldFilament.kolicina,
      cena: oldFilament.cena,
      status: oldFilament.status
    }
  };
  
  // Add tags based on properties
  if (material.modifier === 'Silk') newFilament.tags.push('silk');
  if (material.modifier === 'Matte') newFilament.tags.push('matte');
  if (material.modifier === 'CF') newFilament.tags.push('engineering', 'carbon-fiber');
  if (material.modifier === 'Wood') newFilament.tags.push('specialty', 'wood-fill');
  if (material.modifier === 'Glow') newFilament.tags.push('specialty', 'glow-in-dark');
  if (material.base === 'PETG') newFilament.tags.push('engineering', 'chemical-resistant');
  if (material.base === 'ABS') newFilament.tags.push('engineering', 'high-temp');
  if (material.base === 'TPU') newFilament.tags.push('flexible', 'engineering');
  if (newFilament.condition.isRefill) newFilament.tags.push('refill', 'eco-friendly');
  
  return newFilament;
}

async function migrateData() {
  console.log('Starting migration to new data structure...');
  
  try {
    // Scan all existing items
    const scanParams = {
      TableName: TABLE_NAME
    };
    
    const items = [];
    let lastEvaluatedKey = null;
    
    do {
      if (lastEvaluatedKey) {
        scanParams.ExclusiveStartKey = lastEvaluatedKey;
      }
      
      const result = await dynamodb.scan(scanParams).promise();
      items.push(...result.Items);
      lastEvaluatedKey = result.LastEvaluatedKey;
    } while (lastEvaluatedKey);
    
    console.log(`Found ${items.length} items to migrate`);
    
    // Check if already migrated
    if (items.length > 0 && items[0].material && items[0].inventory) {
      console.log('Data appears to be already migrated!');
      const confirm = process.argv.includes('--force');
      if (!confirm) {
        console.log('Use --force flag to force migration');
        return;
      }
    }
    
    // Migrate each item
    const migratedItems = items.map(item => migrateFilament(item));
    
    // Show sample
    console.log('\nSample migrated data:');
    console.log(JSON.stringify(migratedItems[0], null, 2));
    
    // Update items in batches
    const chunks = [];
    for (let i = 0; i < migratedItems.length; i += 25) {
      chunks.push(migratedItems.slice(i, i + 25));
    }
    
    console.log(`\nUpdating ${migratedItems.length} items in DynamoDB...`);
    
    for (const chunk of chunks) {
      const params = {
        RequestItems: {
          [TABLE_NAME]: chunk.map(item => ({
            PutRequest: { Item: item }
          }))
        }
      };
      
      await dynamodb.batchWrite(params).promise();
      console.log(`Updated ${chunk.length} items`);
    }
    
    console.log('\n✅ Migration completed successfully!');
    
    // Show summary
    const summary = {
      totalItems: migratedItems.length,
      brands: [...new Set(migratedItems.map(i => i.brand))],
      materials: [...new Set(migratedItems.map(i => i.material.base))],
      modifiers: [...new Set(migratedItems.map(i => i.material.modifier).filter(Boolean))],
      storageConditions: [...new Set(migratedItems.map(i => i.condition.storageCondition))],
      totalInventory: migratedItems.reduce((sum, i) => sum + i.inventory.total, 0),
      availableInventory: migratedItems.reduce((sum, i) => sum + i.inventory.available, 0)
    };
    
    console.log('\nMigration Summary:');
    console.log(JSON.stringify(summary, null, 2));
    
  } catch (error) {
    console.error('Migration failed:', error);
    process.exit(1);
  }
}

// Run migration
if (require.main === module) {
  console.log('Data Structure Migration Tool');
  console.log('============================');
  console.log('This will migrate all filaments to the new structure');
  console.log('Old data will be preserved in _legacy field\n');
  
  migrateData();
}