module main

import rand
import time
import os
import crypto.md5

// ============================================================================
// Property 10: Backward Compatibility
// Feature: v-hono-upload-integration, Property 10: Backward Compatibility
// Validates: Requirements 11.2, 11.4
//
// *For any* existing ChunkUploadManager usage without storage configuration,
// the system should behave exactly as before, using local file storage with
// the same response format.
// ============================================================================

const test_iterations = 100
const test_temp_dir = './test_backward_compat_chunks'
const test_upload_dir = './test_backward_compat_files'
const test_db_path = './test_backward_compat.db'

// ============================================================================
// Type definitions (copied from upload module for standalone testing)
// ============================================================================

struct ChunkUploadConfig {
pub:
	chunk_size               int    = 1024 * 1024
	max_file_size            int    = 1024 * 1024 * 1024
	max_chunk_size           int    = 10 * 1024 * 1024
	temp_dir                 string = './uploads/chunks'
	upload_dir               string = './uploads/files'
	cleanup_delay            int    = 3600
	clear_chunks_on_complete bool
	db_path                  string = './uploads/files.db'
	merge_buffer_size        int    = 8192
	use_file_service         bool
}

struct FileUploadStatus {
pub:
	file_hash       string
	filename        string
	total_chunks    int
	file_size       int
	chunk_size      int
	created_at      int
pub mut:
	uploaded_chunks []int
	status          string
	updated_at      int
}

// ============================================================================
// Test infrastructure
// ============================================================================

struct PropertyTestStats {
mut:
	total_tests  int
	passed_tests int
	failed_tests int
}

fn (mut stats PropertyTestStats) run_property_test(test_name string, test_func fn () bool) {
	stats.total_tests++
	print('🔬 ${test_name}... ')

	if test_func() {
		stats.passed_tests++
		println('✅')
	} else {
		stats.failed_tests++
		println('❌')
	}
}

fn (stats PropertyTestStats) print_summary() {
	println('\n=== Backward Compatibility 属性测试总结 ===')
	println('总测试数: ${stats.total_tests}')
	println('通过: ${stats.passed_tests}')
	println('失败: ${stats.failed_tests}')

	if stats.failed_tests == 0 {
		println('🎉 所有属性测试通过！')
	} else {
		println('⚠️  有 ${stats.failed_tests} 个属性测试失败')
	}
}

fn generate_random_bytes(min_len int, max_len int) []u8 {
	len := rand.int_in_range(min_len, max_len) or { min_len }
	mut result := []u8{len: len}
	for i in 0 .. len {
		result[i] = u8(rand.int_in_range(0, 256) or { 0 })
	}
	return result
}

fn generate_random_filename() string {
	chars := 'abcdefghijklmnopqrstuvwxyz0123456789'
	len := rand.int_in_range(5, 20) or { 10 }
	mut result := ''
	for _ in 0 .. len {
		idx := rand.int_in_range(0, chars.len) or { 0 }
		result += chars[idx].ascii_str()
	}
	extensions := ['.txt', '.bin', '.dat', '.json', '.xml']
	ext_idx := rand.int_in_range(0, extensions.len) or { 0 }
	return result + extensions[ext_idx]
}

fn calculate_md5_hash(data []u8) string {
	hash := md5.sum(data)
	mut result := ''
	for b in hash {
		result += '${b:02x}'
	}
	return result
}

fn cleanup_test_dirs() {
	os.rmdir_all(test_temp_dir) or {}
	os.rmdir_all(test_upload_dir) or {}
	os.rm(test_db_path) or {}
	os.rm('${test_db_path}-shm') or {}
	os.rm('${test_db_path}-wal') or {}
}

// ============================================================================
// Property 10.1: Default Config Backward Compatibility
// When no storage configuration is provided, ChunkUploadConfig should use
// default values that match the original behavior
// ============================================================================
fn test_property_10_1_default_config_backward_compat() bool {
	for i in 0 .. test_iterations {
		// Create config with default values (no use_file_service)
		config := ChunkUploadConfig{
			temp_dir: test_temp_dir
			upload_dir: test_upload_dir
			db_path: test_db_path
		}

		// Verify default values match original behavior
		if config.chunk_size != 1024 * 1024 {
			println('  Iteration ${i}: Default chunk_size mismatch. Expected: ${1024 * 1024}, Got: ${config.chunk_size}')
			return false
		}

		if config.max_file_size != 1024 * 1024 * 1024 {
			println('  Iteration ${i}: Default max_file_size mismatch. Expected: ${1024 * 1024 * 1024}, Got: ${config.max_file_size}')
			return false
		}

		if config.max_chunk_size != 10 * 1024 * 1024 {
			println('  Iteration ${i}: Default max_chunk_size mismatch. Expected: ${10 * 1024 * 1024}, Got: ${config.max_chunk_size}')
			return false
		}

		if config.cleanup_delay != 3600 {
			println('  Iteration ${i}: Default cleanup_delay mismatch. Expected: 3600, Got: ${config.cleanup_delay}')
			return false
		}

		if config.merge_buffer_size != 8192 {
			println('  Iteration ${i}: Default merge_buffer_size mismatch. Expected: 8192, Got: ${config.merge_buffer_size}')
			return false
		}

		// use_file_service should default to false
		if config.use_file_service != false {
			println('  Iteration ${i}: Default use_file_service should be false')
			return false
		}
	}

	return true
}

// ============================================================================
// Property 10.2: FileUploadStatus Structure Compatibility
// The FileUploadStatus structure should maintain the same fields and types
// ============================================================================
fn test_property_10_2_file_upload_status_compat() bool {
	for i in 0 .. test_iterations {
		// Generate random values
		file_hash := calculate_md5_hash(generate_random_bytes(10, 100))
		filename := generate_random_filename()
		total_chunks := rand.int_in_range(1, 100) or { 10 }
		file_size := rand.int_in_range(1000, 1000000) or { 10000 }
		chunk_size := rand.int_in_range(1024, 1024 * 1024) or { 1024 * 1024 }
		now := int(time.now().unix())

		// Create FileUploadStatus with all fields
		status := FileUploadStatus{
			file_hash: file_hash
			filename: filename
			total_chunks: total_chunks
			file_size: file_size
			chunk_size: chunk_size
			created_at: now
			updated_at: now
			uploaded_chunks: [0, 1, 2]
			status: 'uploading'
		}

		// Verify all fields are accessible and have correct values
		if status.file_hash != file_hash {
			println('  Iteration ${i}: file_hash mismatch')
			return false
		}

		if status.filename != filename {
			println('  Iteration ${i}: filename mismatch')
			return false
		}

		if status.total_chunks != total_chunks {
			println('  Iteration ${i}: total_chunks mismatch')
			return false
		}

		if status.file_size != file_size {
			println('  Iteration ${i}: file_size mismatch')
			return false
		}

		if status.chunk_size != chunk_size {
			println('  Iteration ${i}: chunk_size mismatch')
			return false
		}

		if status.created_at != now {
			println('  Iteration ${i}: created_at mismatch')
			return false
		}

		if status.uploaded_chunks.len != 3 {
			println('  Iteration ${i}: uploaded_chunks length mismatch')
			return false
		}

		if status.status != 'uploading' {
			println('  Iteration ${i}: status mismatch')
			return false
		}
	}

	return true
}

// ============================================================================
// Property 10.3: Local File Storage Path Consistency
// When use_file_service is false, files should be stored in upload_dir
// with the same path format as before
// ============================================================================
fn test_property_10_3_local_storage_path_consistency() bool {
	cleanup_test_dirs()
	defer {
		cleanup_test_dirs()
	}

	for i in 0 .. test_iterations {
		// Generate random file data
		data := generate_random_bytes(100, 1000)
		file_hash := calculate_md5_hash(data)
		filename := generate_random_filename()

		// Get file extension
		parts := filename.split('.')
		file_ext := if parts.len > 1 { '.${parts.last()}' } else { '' }

		// Expected final filename format: {file_hash}{file_ext}
		expected_final_filename := '${file_hash}${file_ext}'
		expected_final_path := os.join_path(test_upload_dir, expected_final_filename)

		// Verify the path format is consistent
		if !expected_final_path.contains(file_hash) {
			println('  Iteration ${i}: Final path should contain file hash')
			return false
		}

		if file_ext != '' && !expected_final_path.ends_with(file_ext) {
			println('  Iteration ${i}: Final path should end with file extension')
			return false
		}
	}

	return true
}

// ============================================================================
// Property 10.4: Chunk Directory Structure Consistency
// Chunks should be stored in temp_dir/{file_hash}/{chunk_size}/ format
// ============================================================================
fn test_property_10_4_chunk_directory_structure() bool {
	cleanup_test_dirs()
	defer {
		cleanup_test_dirs()
	}

	for i in 0 .. test_iterations {
		// Generate random values
		data := generate_random_bytes(100, 1000)
		file_hash := calculate_md5_hash(data)
		chunk_size := rand.int_in_range(1024, 1024 * 1024) or { 1024 * 1024 }
		chunk_index := rand.int_in_range(0, 100) or { 0 }

		// Expected chunk directory format
		expected_chunk_dir := os.join_path(test_temp_dir, file_hash, chunk_size.str())
		expected_chunk_path := os.join_path(expected_chunk_dir, 'chunk_${chunk_index}.part')

		// Verify the path format is consistent
		if !expected_chunk_dir.contains(file_hash) {
			println('  Iteration ${i}: Chunk dir should contain file hash')
			return false
		}

		if !expected_chunk_dir.contains(chunk_size.str()) {
			println('  Iteration ${i}: Chunk dir should contain chunk size')
			return false
		}

		if !expected_chunk_path.ends_with('.part') {
			println('  Iteration ${i}: Chunk file should end with .part')
			return false
		}
	}

	return true
}

// ============================================================================
// Property 10.5: Config with use_file_service=false Behaves Like Original
// When use_file_service is explicitly set to false, behavior should be
// identical to the original implementation
// ============================================================================
fn test_property_10_5_explicit_no_file_service() bool {
	for i in 0 .. test_iterations {
		// Create config with explicit use_file_service = false
		config := ChunkUploadConfig{
			temp_dir: test_temp_dir
			upload_dir: test_upload_dir
			db_path: test_db_path
			use_file_service: false
		}

		// Verify use_file_service is false
		if config.use_file_service != false {
			println('  Iteration ${i}: use_file_service should be false')
			return false
		}

		// Verify upload_dir is used (not empty)
		if config.upload_dir == '' {
			println('  Iteration ${i}: upload_dir should not be empty when use_file_service is false')
			return false
		}

		// Verify temp_dir is used (not empty)
		if config.temp_dir == '' {
			println('  Iteration ${i}: temp_dir should not be empty')
			return false
		}
	}

	return true
}

// ============================================================================
// Property 10.6: Response Format Consistency
// The response format for chunk upload should remain compatible
// ============================================================================
fn test_property_10_6_response_format_consistency() bool {
	// Test that expected response fields are present in the format
	// Original format: {"success": true, "chunk_index": N, "all_chunk_uploaded": false, "message": "..."}
	// Or: {"success": true, "all_chunk_uploaded": true, "file_path": "...", "file_uuid": "...", "message": "..."}

	for i in 0 .. test_iterations {
		chunk_index := rand.int_in_range(0, 100) or { 0 }
		file_hash := calculate_md5_hash(generate_random_bytes(10, 100))
		file_ext := '.txt'
		file_uuid := 'test-uuid-${i}'

		// Test partial upload response format
		partial_response := '{"success": true, "chunk_index": ${chunk_index}, "all_chunk_uploaded": false, "message": "Chunk uploaded successfully"}'

		if !partial_response.contains('"success": true') {
			println('  Iteration ${i}: Partial response should contain success field')
			return false
		}

		if !partial_response.contains('"chunk_index":') {
			println('  Iteration ${i}: Partial response should contain chunk_index field')
			return false
		}

		if !partial_response.contains('"all_chunk_uploaded": false') {
			println('  Iteration ${i}: Partial response should contain all_chunk_uploaded field')
			return false
		}

		// Test complete upload response format (local storage)
		file_path := os.join_path(test_upload_dir, '${file_hash}${file_ext}')
		complete_response := '{"success": true, "all_chunk_uploaded": true, "file_path": "${file_path}", "file_uuid": "${file_uuid}", "message": "File merged successfully"}'

		if !complete_response.contains('"success": true') {
			println('  Iteration ${i}: Complete response should contain success field')
			return false
		}

		if !complete_response.contains('"all_chunk_uploaded": true') {
			println('  Iteration ${i}: Complete response should contain all_chunk_uploaded field')
			return false
		}

		if !complete_response.contains('"file_path":') {
			println('  Iteration ${i}: Complete response should contain file_path field')
			return false
		}

		if !complete_response.contains('"file_uuid":') {
			println('  Iteration ${i}: Complete response should contain file_uuid field')
			return false
		}
	}

	return true
}

// ============================================================================
// Main test runner
// ============================================================================
fn main() {
	println('=== Property 10: Backward Compatibility 属性测试 ===')
	println('Feature: v-hono-upload-integration')
	println('Validates: Requirements 11.2, 11.4')
	println('')

	rand.seed([u32(time.now().unix()), u32(time.now().unix() >> 32)])

	mut stats := PropertyTestStats{}

	stats.run_property_test('Property 10.1: Default Config Backward Compatibility', test_property_10_1_default_config_backward_compat)
	stats.run_property_test('Property 10.2: FileUploadStatus Structure Compatibility', test_property_10_2_file_upload_status_compat)
	stats.run_property_test('Property 10.3: Local Storage Path Consistency', test_property_10_3_local_storage_path_consistency)
	stats.run_property_test('Property 10.4: Chunk Directory Structure Consistency', test_property_10_4_chunk_directory_structure)
	stats.run_property_test('Property 10.5: Explicit No FileService Behavior', test_property_10_5_explicit_no_file_service)
	stats.run_property_test('Property 10.6: Response Format Consistency', test_property_10_6_response_format_consistency)

	stats.print_summary()

	// Exit with error code if any tests failed
	if stats.failed_tests > 0 {
		exit(1)
	}
}