/**
 * VFS Import Verification Test
 *
 * This test verifies that brain.import() creates VFS entities correctly.
 * Created to investigate a consumer's report of empty VFS after import.
 *
 * Expected behavior:
 * 1. Import with vfsPath creates directory entities
 * 2. VFS entities have vfsType metadata
 * 3. Directory hierarchy is created with Contains relationships
 * 4. getDirectChildren() returns imported files
 */

import { describe, it, expect, beforeEach } from 'vitest'
import { Brainy } from '../../src/brainy.js'
import * as XLSX from 'xlsx'

describe('VFS Import Verification (VFS import bug investigation)', () => {
  let brain: Brainy

  beforeEach(async () => {
    brain = new Brainy({ requireSubtype: false,
      storage: { type: 'memory' as const }
    })
    await brain.init()
  })

  it('should create VFS entities during import with vfsPath', async () => {
    // Create test Excel file (matching the reported scenario)
    const testData = [
      {
        'Term': 'Alice',
        'Definition': 'A character from Wonderland',
        'Type': 'Person',
        'Related Terms': 'Wonderland'
      },
      {
        'Term': 'Wonderland',
        'Definition': 'A magical place',
        'Type': 'Place',
        'Related Terms': 'Alice'
      }
    ]

    const worksheet = XLSX.utils.json_to_sheet(testData)
    const workbook = XLSX.utils.book_new()
    XLSX.utils.book_append_sheet(workbook, worksheet, 'Glossary')
    const buffer = XLSX.write(workbook, { type: 'buffer', bookType: 'xlsx' })

    console.log('📥 Step 1: Import with VFS options...')
    const result = await brain.import(buffer, {
      format: 'excel',
      vfsPath: '/imports/test-glossary',
      groupBy: 'type',
      preserveSource: true,
      enableNeuralExtraction: true,
      enableRelationshipInference: true
    })

    console.log('✅ Step 1 Complete:')
    console.log(`   - Format: ${result.format}`)
    console.log(`   - Entities extracted: ${result.stats.entitiesExtracted}`)
    console.log(`   - VFS files created: ${result.stats.vfsFilesCreated}`)
    console.log(`   - VFS root: ${result.vfs.rootPath}`)
    console.log(`   - VFS directories: ${result.vfs.directories.length}`)
    console.log(`   - VFS files: ${result.vfs.files.length}`)

    // Verify import result
    expect(result.format).toBe('excel')
    expect(result.stats.entitiesExtracted).toBeGreaterThanOrEqual(2)
    expect(result.stats.vfsFilesCreated).toBeGreaterThan(0)
    expect(result.vfs.rootPath).toBe('/imports/test-glossary')
    expect(result.vfs.directories.length).toBeGreaterThan(0)
    expect(result.vfs.files.length).toBeGreaterThan(0)

    console.log('\n🔍 Step 2: Check VFS entities in storage...')

    // Check if VFS entities exist in storage
    const allEntities = await brain.find({ limit: 1000 })
    console.log(`   - Total entities in brain: ${allEntities.length}`)

    const vfsEntities = allEntities.filter(e =>
      e.metadata?.vfsType && e.metadata?.path
    )
    console.log(`   - Entities with vfsType: ${vfsEntities.length}`)

    if (vfsEntities.length > 0) {
      console.log('   ✅ VFS entities found!')
      console.log('   Sample VFS entities:')
      vfsEntities.slice(0, 5).forEach(e => {
        console.log(`     - ${e.metadata.path} (${e.metadata.vfsType})`)
      })
    } else {
      console.log('   ❌ NO VFS entities found! This is the bug!')
    }

    // CRITICAL CHECK: VFS entities MUST exist
    expect(vfsEntities.length).toBeGreaterThan(0)

    console.log('\n📂 Step 3: Initialize VFS and query...')

    // Get VFS instance
    const vfs = brain.vfs
    console.log('   - Got VFS instance')

    // Initialize VFS
    await vfs.init()
    console.log('   - VFS initialized')

    // Query root directory
    const rootItems = await vfs.getDirectChildren('/')
    console.log(`   - Root items: ${rootItems.length}`)

    if (rootItems.length > 0) {
      console.log('   ✅ Root directory has items!')
      rootItems.forEach(item => {
        console.log(`     - ${item.metadata.name} (${item.metadata.vfsType})`)
      })
    } else {
      console.log('   ❌ Root directory is empty!')
    }

    // CRITICAL CHECK: Root MUST have items (at least /imports)
    expect(rootItems.length).toBeGreaterThan(0)

    // Check /imports directory
    console.log('\n📂 Step 4: Check /imports directory...')
    const importsItems = await vfs.getDirectChildren('/imports')
    console.log(`   - Items in /imports: ${importsItems.length}`)

    if (importsItems.length > 0) {
      console.log('   ✅ /imports has items!')
      importsItems.forEach(item => {
        console.log(`     - ${item.metadata.name} (${item.metadata.vfsType})`)
      })
    } else {
      console.log('   ❌ /imports is empty!')
    }

    // CRITICAL CHECK: /imports MUST have items (at least test-glossary)
    expect(importsItems.length).toBeGreaterThan(0)

    // Check import directory
    console.log('\n📂 Step 5: Check /imports/test-glossary directory...')
    const glossaryItems = await vfs.getDirectChildren('/imports/test-glossary')
    console.log(`   - Items in /imports/test-glossary: ${glossaryItems.length}`)

    if (glossaryItems.length > 0) {
      console.log('   ✅ Import directory has items!')
      glossaryItems.forEach(item => {
        console.log(`     - ${item.metadata.name} (${item.metadata.vfsType})`)
      })
    } else {
      console.log('   ❌ Import directory is empty!')
    }

    // CRITICAL CHECK: Import directory MUST have items
    // Should have: Characters/, Places/, _source.xlsx, _metadata.json, _relationships.json
    expect(glossaryItems.length).toBeGreaterThanOrEqual(3)

    console.log('\n✅ ALL CHECKS PASSED! VFS import is working correctly.')
  }, 60000) // 60s timeout

  it('should work without manual vfs.init() after import (after refactor)', async () => {
    // Create test data
    const testData = [
      { 'Name': 'Test Entity', 'Type': 'Thing' }
    ]

    const worksheet = XLSX.utils.json_to_sheet(testData)
    const workbook = XLSX.utils.book_new()
    XLSX.utils.book_append_sheet(workbook, worksheet, 'Data')
    const buffer = XLSX.write(workbook, { type: 'buffer', bookType: 'xlsx' })

    console.log('📥 Import with VFS...')
    await brain.import(buffer, {
      format: 'excel',
      vfsPath: '/imports/test',
      groupBy: 'type'
    })

    console.log('📂 Get VFS (should be initialized by import)...')
    const vfs = brain.vfs

    // AFTER REFACTOR: This should work without calling vfs.init()
    // Because VFSStructureGenerator uses brain.vfs which caches the instance
    console.log('🔍 Query root (without manual init)...')

    try {
      const items = await vfs.getDirectChildren('/')
      console.log(`   ✅ SUCCESS: Got ${items.length} items without manual init!`)
      expect(items.length).toBeGreaterThan(0)
    } catch (error: any) {
      if (error.message.includes('not initialized')) {
        console.log('   ❌ VFS not initialized - refactor not yet implemented')
        console.log('   This test will pass after VFSStructureGenerator refactor')
        // For now, manually init and verify it works
        await vfs.init()
        const items = await vfs.getDirectChildren('/')
        expect(items.length).toBeGreaterThan(0)
      } else {
        throw error
      }
    }
  }, 60000)

  it('should match the reported scenario exactly', async () => {
    // Replicate a consumer's exact scenario
    const testData = [
      { 'Term': 'Westland', 'Definition': 'Ancient kingdom', 'Type': 'Place' },
      { 'Term': 'Capital City', 'Definition': 'Main city', 'Type': 'Place' },
      { 'Term': 'Royal Dynasty', 'Definition': 'Noble family', 'Type': 'Organization' }
    ]

    const worksheet = XLSX.utils.json_to_sheet(testData)
    const workbook = XLSX.utils.book_new()
    XLSX.utils.book_append_sheet(workbook, worksheet, 'Glossary')
    const buffer = XLSX.write(workbook, { type: 'buffer', bookType: 'xlsx' })

    console.log('📥 Importing (the reported scenario)...')
    const filename = 'Tales from Talifar Glossary.xlsx'
    const timestamp = Date.now()

    const result = await brain.import(buffer, {
      vfsPath: `/imports/${filename}-${timestamp}`,
      preserveSource: true,
      groupBy: 'type',
      enableNeuralExtraction: true,
      enableRelationshipInference: true,
      enableConceptExtraction: true
    })

    console.log('✅ Import result:')
    console.log(`   - Entities: ${result.stats.entitiesExtracted}`)
    console.log(`   - Graph nodes: ${result.stats.graphNodesCreated}`)
    console.log(`   - Graph edges: ${result.stats.graphEdgesCreated}`)
    console.log(`   - VFS files: ${result.stats.vfsFilesCreated}`)

    // Consumer's check: Initialize VFS
    console.log('\n📂 Initializing VFS (post-fix)...')
    const vfs = brain.vfs
    await vfs.init()

    // a consumer's check: Query root
    console.log('🔍 Querying root directory...')
    const rootItems = await vfs.getDirectChildren('/')
    console.log(`   - Items in root: ${rootItems.length}`)

    if (rootItems.length === 0) {
      console.log('   ❌ BUG REPRODUCED: Empty root after import + init!')

      // Debug: Check storage for VFS entities
      const allEntities = await brain.find({ limit: 1000 })
      const vfsEntities = allEntities.filter(e => e.metadata?.vfsType)
      console.log(`   Debug: ${vfsEntities.length} VFS entities in storage`)

      if (vfsEntities.length === 0) {
        console.log('   Root cause: Import did NOT create VFS entities!')
      } else {
        console.log('   Root cause: VFS entities exist but query returns empty!')
      }
    } else {
      console.log('   ✅ Root has items (bug not reproduced)')
    }

    // This test will fail if the bug exists
    expect(rootItems.length).toBeGreaterThan(0)
  }, 60000)
})