<?php

namespace App\Http\Controllers\Transactions;

use App\Http\Controllers\Controller;
use Illuminate\Http\Request;
use App\Models\Precheck;
use App\Models\Transaction;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Facades\Log;

class PrechecksController extends Controller
{
    public function create(Transaction $transaction)
    {
        $acConditions = Precheck::getAcConditionOptions();
        $blowerConditions = Precheck::getBlowerConditionOptions();
        $evaporatorConditions = Precheck::getEvaporatorConditionOptions();
        $compressorConditions = Precheck::getCompressorConditionOptions();
        
        return view('transaction.prechecks.create', compact(
            'transaction', 
            'acConditions', 
            'blowerConditions', 
            'evaporatorConditions', 
            'compressorConditions'
        ));
    }

    public function store(Request $request, Transaction $transaction)
    {
        $request->validate([
            'kilometer' => 'required|numeric|min:0',
            'pressure_high' => 'required|numeric|min:0',
            'pressure_low' => 'nullable|numeric|min:0',
            'cabin_temperature' => 'nullable|numeric',
            'cabin_temperature_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'ac_condition' => 'nullable|in:' . implode(',', Precheck::getAcConditionOptions()),
            'ac_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'blower_condition' => 'nullable|in:' . implode(',', Precheck::getBlowerConditionOptions()),
            'blower_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'evaporator_condition' => 'nullable|in:' . implode(',', Precheck::getEvaporatorConditionOptions()),
            'evaporator_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'compressor_condition' => 'nullable|in:' . implode(',', Precheck::getCompressorConditionOptions()),
            'precheck_notes' => 'nullable|string',
            'front_image' => 'required|image|mimes:jpeg,png,jpg|max:20480',
        ]);

        $data = [
            'transaction_id' => $transaction->id,
            'precheck_by' => auth()->id(),
            'precheck_at' => now(),
            'police_number' => $transaction->police_number,
            'spk_number' => $transaction->spk,
            'kilometer' => $request->kilometer,
            'pressure_high' => $request->pressure_high,
            'pressure_low' => $request->pressure_low,
            'cabin_temperature' => $request->cabin_temperature,
            'ac_condition' => $request->ac_condition,
            'blower_condition' => $request->blower_condition,
            'evaporator_condition' => $request->evaporator_condition,
            'compressor_condition' => $request->compressor_condition,
            'precheck_notes' => $request->precheck_notes,
        ];

        // Handle file uploads
        $imageFields = [
            'front_image', 'cabin_temperature_image', 'ac_image', 
            'blower_image', 'evaporator_image'
        ];

        foreach ($imageFields as $field) {
            if ($request->hasFile($field) && $request->file($field)->isValid()) {
                try {
                    $file = $request->file($field);
                    
                    // Enhanced security validation
                    if (!$this->isValidImageFile($file)) {
                        return back()->withErrors(['error' => 'File tidak valid atau berbahaya: ' . $field]);
                    }
                    
                    // Generate unique filename with transaction ID
                    $filename = time() . '_' . uniqid() . '_' . $transaction->id . '_' . $field . '.' . $file->getClientOriginalExtension();
                    
                    // Create directory path: transactions/{transaction_id}/precheck/
                    $directory = 'transactions/' . $transaction->id . '/precheck';
                    
                    // Ensure base storage directory exists
                    $this->ensureStorageDirectoryExists();
                    
                    // Ensure transactions directory exists
                    if (!Storage::disk('public')->exists('transactions')) {
                        Storage::disk('public')->makeDirectory('transactions', 0755, true);
                        Log::info('Created transactions directory');
                    }
                    
                    // Ensure transaction ID directory exists
                    $transactionDir = 'transactions/' . $transaction->id;
                    if (!Storage::disk('public')->exists($transactionDir)) {
                        Storage::disk('public')->makeDirectory($transactionDir, 0755, true);
                        Log::info('Created transaction directory: ' . $transactionDir);
                    }
                    
                    // Ensure precheck directory exists
                    if (!Storage::disk('public')->exists($directory)) {
                        Storage::disk('public')->makeDirectory($directory, 0755, true);
                        Log::info('Created precheck directory: ' . $directory);
                    }
                    
                    // Store file in organized directory structure
                    $path = $file->storeAs($directory, $filename, 'public');
                    
                    // Store file path
                    $data[$field] = $path;
                    
                    // Store metadata
                    $data[$field . '_metadata'] = [
                        'original_name' => $file->getClientOriginalName(),
                        'size' => $file->getSize(),
                        'mime_type' => $file->getMimeType(),
                        'uploaded_at' => now()->toISOString(),
                        'transaction_id' => $transaction->id,
                        'filename' => $filename,
                    ];
                    
                    Log::info('File uploaded successfully: ' . $path);
                    
                } catch (\Exception $e) {
                    // Log error for debugging
                    Log::error('File upload failed: ' . $e->getMessage(), [
                        'field' => $field,
                        'file' => $file->getClientOriginalName(),
                        'transaction_id' => $transaction->id,
                        'error' => $e->getMessage(),
                        'trace' => $e->getTraceAsString()
                    ]);
                    
                    return back()->withErrors(['error' => 'Gagal mengupload file: ' . $field . '. Error: ' . $e->getMessage()]);
                }
            }
        }

        try {
            Precheck::create($data);
            return redirect()->route('transaction')->with('success', 'Precheck berhasil disimpan');
        } catch (\Exception $e) {
            Log::error('Precheck creation failed: ' . $e->getMessage());
            return back()->withErrors(['error' => 'Gagal menyimpan data precheck. Silakan coba lagi.']);
        }
    }

    public function edit(Transaction $transaction, Precheck $precheck)
    {
        
        $acConditions = Precheck::getAcConditionOptions();
        $blowerConditions = Precheck::getBlowerConditionOptions();
        $evaporatorConditions = Precheck::getEvaporatorConditionOptions();
        $compressorConditions = Precheck::getCompressorConditionOptions();

        return view('transaction.prechecks.edit', compact(
            'transaction', 
            'precheck', 
            'acConditions', 
            'blowerConditions', 
            'evaporatorConditions', 
            'compressorConditions'
        ));
    }

    public function update(Request $request, Transaction $transaction, Precheck $precheck)
    {
        
        $request->validate([
            'kilometer' => 'required|numeric|min:0',
            'pressure_high' => 'required|numeric|min:0',
            'pressure_low' => 'nullable|numeric|min:0',
            'cabin_temperature' => 'nullable|numeric',
            'cabin_temperature_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'ac_condition' => 'nullable|in:' . implode(',', Precheck::getAcConditionOptions()),
            'ac_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'blower_condition' => 'nullable|in:' . implode(',', Precheck::getBlowerConditionOptions()),
            'blower_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'evaporator_condition' => 'nullable|in:' . implode(',', Precheck::getEvaporatorConditionOptions()),
            'evaporator_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
            'compressor_condition' => 'nullable|in:' . implode(',', Precheck::getCompressorConditionOptions()),
            'precheck_notes' => 'nullable|string',
            'front_image' => 'nullable|image|mimes:jpeg,png,jpg|max:20480',
        ]);

        $data = [
            'kilometer' => $request->kilometer,
            'pressure_high' => $request->pressure_high,
            'pressure_low' => $request->pressure_low,
            'cabin_temperature' => $request->cabin_temperature,
            'ac_condition' => $request->ac_condition,
            'blower_condition' => $request->blower_condition,
            'evaporator_condition' => $request->evaporator_condition,
            'compressor_condition' => $request->compressor_condition,
            'precheck_notes' => $request->precheck_notes,
        ];

        // Handle file uploads with security validation
        $imageFields = [
            'front_image', 'cabin_temperature_image', 'ac_image', 
            'blower_image', 'evaporator_image'
        ];

        foreach ($imageFields as $field) {
            if ($request->hasFile($field) && $request->file($field)->isValid()) {
                try {
                    $file = $request->file($field);
                    
                    // Enhanced security validation
                    if (!$this->isValidImageFile($file)) {
                        return back()->withErrors(['error' => 'File tidak valid atau berbahaya: ' . $field]);
                    }
                    
                    // Generate unique filename with transaction ID
                    $filename = time() . '_' . uniqid() . '_' . $transaction->id . '_' . $field . '.' . $file->getClientOriginalExtension();
                    
                    // Create directory path: transactions/{transaction_id}/precheck/
                    $directory = 'transactions/' . $transaction->id . '/precheck';
                    
                    // Ensure base storage directory exists
                    $this->ensureStorageDirectoryExists();
                    
                    // Ensure transactions directory exists
                    if (!Storage::disk('public')->exists('transactions')) {
                        Storage::disk('public')->makeDirectory('transactions', 0755, true);
                        Log::info('Created transactions directory');
                    }
                    
                    // Ensure transaction ID directory exists
                    $transactionDir = 'transactions/' . $transaction->id;
                    if (!Storage::disk('public')->exists($transactionDir)) {
                        Storage::disk('public')->makeDirectory($transactionDir, 0755, true);
                        Log::info('Created transaction directory: ' . $transactionDir);
                    }
                    
                    // Ensure precheck directory exists
                    if (!Storage::disk('public')->exists($directory)) {
                        Storage::disk('public')->makeDirectory($directory, 0755, true);
                        Log::info('Created precheck directory: ' . $directory);
                    }
                    
                    // Delete old file if exists
                    if ($precheck->$field && Storage::disk('public')->exists($precheck->$field)) {
                        Storage::disk('public')->delete($precheck->$field);
                    }
                    
                    // Store file in organized directory structure
                    $path = $file->storeAs($directory, $filename, 'public');
                    
                    // Store file path
                    $data[$field] = $path;
                    
                    // Store metadata
                    $data[$field . '_metadata'] = [
                        'original_name' => $file->getClientOriginalName(),
                        'size' => $file->getSize(),
                        'mime_type' => $file->getMimeType(),
                        'uploaded_at' => now()->toISOString(),
                        'transaction_id' => $transaction->id,
                        'filename' => $filename,
                    ];
                    
                    Log::info('File uploaded successfully: ' . $path);
                    
                } catch (\Exception $e) {
                    // Log error for debugging
                    Log::error('File upload failed: ' . $e->getMessage(), [
                        'field' => $field,
                        'file' => $file->getClientOriginalName(),
                        'transaction_id' => $transaction->id,
                        'error' => $e->getMessage(),
                        'trace' => $e->getTraceAsString()
                    ]);
                    
                    return back()->withErrors(['error' => 'Gagal mengupload file: ' . $field . '. Error: ' . $e->getMessage()]);
                }
            }
        }

        try {
            $precheck->update($data);
            return redirect()->route('transaction')->with('success', 'Precheck berhasil diperbarui');
        } catch (\Exception $e) {
            Log::error('Precheck update failed: ' . $e->getMessage());
            return back()->withErrors(['error' => 'Gagal memperbarui data precheck. Silakan coba lagi.']);
        }
    }

    public function print($transaction_id)
    {
        try {
            $precheck = Precheck::where('transaction_id', $transaction_id)->firstOrFail();
            return view('transaction.prechecks.print', compact('precheck'));
        } catch (\Exception $e) {
            Log::error('Error printing precheck: ' . $e->getMessage());
            return back()->with('error', 'Gagal membuka halaman print precheck.');
        }
    }

    /**
     * Ensure the base storage directory exists
     */
    private function ensureStorageDirectoryExists()
    {
        $storagePath = storage_path('app/public');
        
        if (!is_dir($storagePath)) {
            if (!mkdir($storagePath, 0755, true)) {
                Log::error('Failed to create storage directory: ' . $storagePath);
                throw new \Exception('Cannot create storage directory: ' . $storagePath . '. Please run: php fix_permissions.php or manually create the directory.');
            }
            Log::info('Created storage directory: ' . $storagePath);
        }
        
        // Check if directory is writable
        if (!is_writable($storagePath)) {
            Log::error('Storage directory is not writable: ' . $storagePath);
            throw new \Exception(
                'Storage directory is not writable: ' . $storagePath . '. ' .
                'Please run one of these commands from your project root: ' .
                '1) php fix_permissions.php ' .
                '2) chmod -R 775 storage/ ' .
                '3) mkdir -p storage/app/public/transactions/{transaction_id}/precheck'
            );
        }
        
        // Check if we can create subdirectories
        $testDir = $storagePath . '/test_' . time();
        if (!mkdir($testDir, 0755, true)) {
            Log::error('Cannot create subdirectories in storage: ' . $storagePath);
            throw new \Exception(
                'Cannot create subdirectories in storage. ' .
                'Please check permissions and run: php fix_permissions.php'
            );
        }
        
        // Clean up test directory
        rmdir($testDir);
        Log::info('Storage directory is properly configured: ' . $storagePath);
    }

    /**
     * Enhanced security validation for image files to prevent RCE attacks
     *
     * @param \Illuminate\Http\UploadedFile $file
     * @return bool
     */
    private function isValidImageFile($file)
    {
        try {
            // 1. Check file extension (whitelist approach)
            $allowedExtensions = ['jpg', 'jpeg', 'png'];
            $extension = strtolower($file->getClientOriginalExtension());
            
            if (!in_array($extension, $allowedExtensions)) {
                Log::warning('Invalid file extension: ' . $extension, [
                    'filename' => $file->getClientOriginalName(),
                    'user_id' => auth()->id()
                ]);
                return false;
            }

            // 2. Check MIME type
            $allowedMimeTypes = [
                'image/jpeg',
                'image/jpg', 
                'image/png'
            ];
            
            $mimeType = $file->getMimeType();
            if (!in_array($mimeType, $allowedMimeTypes)) {
                Log::warning('Invalid MIME type: ' . $mimeType, [
                    'filename' => $file->getClientOriginalName(),
                    'user_id' => auth()->id()
                ]);
                return false;
            }

            // 3. Verify file is actually an image using getimagesize
            $imageInfo = @getimagesize($file->getPathname());
            if ($imageInfo === false) {
                Log::warning('File is not a valid image: ' . $file->getClientOriginalName(), [
                    'user_id' => auth()->id()
                ]);
                return false;
            }

            // 4. Check image dimensions (prevent extremely large images)
            $maxWidth = 5000;
            $maxHeight = 5000;
            if ($imageInfo[0] > $maxWidth || $imageInfo[1] > $maxHeight) {
                Log::warning('Image dimensions too large: ' . $imageInfo[0] . 'x' . $imageInfo[1], [
                    'filename' => $file->getClientOriginalName(),
                    'user_id' => auth()->id()
                ]);
                return false;
            }

            // 5. Check file size (max 20MB)
            $maxSize = 20 * 1024 * 1024; // 20MB
            if ($file->getSize() > $maxSize) {
                Log::warning('File size too large: ' . $file->getSize(), [
                    'filename' => $file->getClientOriginalName(),
                    'user_id' => auth()->id()
                ]);
                return false;
            }

            // 6. Check for suspicious content in filename
            $filename = $file->getClientOriginalName();
            $suspiciousPatterns = [
                '<?php', '<?=', '<script', 'javascript:', 'data:', 'vbscript:',
                '..', '~', '$', '`', '|', '&', ';', '(', ')', '{', '}',
                'exec', 'system', 'shell_exec', 'passthru', 'eval'
            ];
            
            foreach ($suspiciousPatterns as $pattern) {
                if (stripos($filename, $pattern) !== false) {
                    Log::warning('Suspicious filename pattern detected: ' . $pattern, [
                        'filename' => $filename,
                        'user_id' => auth()->id()
                    ]);
                    return false;
                }
            }

            // 7. Additional security: Check file header (magic bytes)
            $handle = fopen($file->getPathname(), 'rb');
            if ($handle) {
                $header = fread($handle, 8);
                fclose($handle);
                
                // Check for valid image headers
                $validHeaders = [
                    "\xFF\xD8\xFF", // JPEG
                    "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A", // PNG
                ];
                
                $isValidHeader = false;
                foreach ($validHeaders as $validHeader) {
                    if (substr($header, 0, strlen($validHeader)) === $validHeader) {
                        $isValidHeader = true;
                        break;
                    }
                }
                
                if (!$isValidHeader) {
                    Log::warning('Invalid file header detected', [
                        'filename' => $filename,
                        'user_id' => auth()->id(),
                        'header' => bin2hex($header)
                    ]);
                    return false;
                }
            }

            Log::info('File validation passed', [
                'filename' => $filename,
                'size' => $file->getSize(),
                'mime_type' => $mimeType,
                'user_id' => auth()->id()
            ]);

            return true;

        } catch (\Exception $e) {
            Log::error('File validation error: ' . $e->getMessage(), [
                'filename' => $file->getClientOriginalName(),
                'user_id' => auth()->id(),
                'error' => $e->getMessage()
            ]);
            return false;
        }
    }
}