Getting Started

Minimal Setup

Installation Add the package via Composer:
```
composer require meenie/javascript-packer
```
Require the autoloader in your project (Laravel handles this automatically if using composer.json).

First Use Case Pack a single JavaScript file:

use Meenie\JavaScriptPacker\Packer;

$packer = new Packer();
$packedCode = $packer->pack('path/to/your/script.js');
file_put_contents('path/to/packed/script.min.js', $packedCode);

Laravel Integration For Laravel, publish the config (if available) and bind the packer to the container in AppServiceProvider:
```
$this->app->singleton(Packer::class, function ($app) {
    return new Packer($app['config']['javascript-packer']);
});
```

Implementation Patterns

Workflows

Asset Optimization Pipeline Use the packer in a Laravel Asset pipeline (e.g., app/Providers/AppServiceProvider):

public function boot()
{
    $this->app->afterResolving('view', function () {
        $packer = app(Packer::class);
        $packed = $packer->pack(public_path('js/app.js'));
        file_put_contents(public_path('js/app.min.js'), $packed);
    });
}

Dynamic Packing in Controllers Pack and serve JS on-demand (e.g., for user-specific scripts):

public function getCustomScript()
{
    $packer = app(Packer::class);
    $packed = $packer->pack(storage_path('scripts/custom.js'));
    return response($packed, 200)->header('Content-Type', 'application/javascript');
}

Combining Multiple Files Pack an array of files into one:

$packer = new Packer();
$packed = $packer->packMultiple([
    'file1.js',
    'file2.js',
    'vendor/script.js'
]);

Integration Tips

Cache Busting: Append a hash to packed filenames to leverage browser caching:

$filename = 'js/app.min.js?v=' . md5($packed);
file_put_contents(public_path($filename), $packed);

Laravel Mix: Use the packer as a custom webpack loader or post-processor for JS files.
Queue Jobs: Offload packing to a queue (e.g., pack:js job) for large projects:
```
PackScriptJob::dispatch('path/to/script.js')->onQueue('packing');
```

Gotchas and Tips

Pitfalls

Encoding Issues Ensure input files are UTF-8 encoded. The packer may corrupt non-UTF-8 files (e.g., legacy scripts with ISO-8859-1). Fix: Normalize files before packing:
```
$content = file_get_contents($file);
$content = mb_convert_encoding($content, 'UTF-8', 'auto');
```
Line Breaks in Output The packer strips whitespace by default. To preserve formatting (e.g., for source maps), use:
```
$packer = new Packer(['preserve_formatting' => true]);
```
Variable Name Collisions The packer shortens variable names (e.g., var x = 1; → var a=1;). This can break:
- Closures relying on specific variable scopes.
- Libraries expecting exact variable names (e.g., window.jQuery). Fix: Exclude files/libraries from packing or use the exclude_vars option:
```
$packer = new Packer(['exclude_vars' => ['jQuery', 'window']]);
```
Memory Limits Packing large files (>10MB) may hit PHP’s memory_limit. Increase it temporarily:
```
ini_set('memory_limit', '256M');
$packer->pack('large-file.js');
```

Debugging

Verbose Output: Enable debug mode to log packing steps:
```
$packer = new Packer(['debug' => true]);
```

Check for Syntax Errors: Packed JS may fail silently. Validate output with:

node -e "require('vm').createScript(require('fs').readFileSync('packed.js'));"

Extension Points

Custom Packer Classes Extend the Packer class to add pre/post-processing:

class CustomPacker extends Packer {
    protected function beforePack($code) {
        return str_replace('// DEBUG', '', $code); // Remove debug comments
    }
}

Hooks for External Tools Integrate with tools like UglifyJS or Terser by wrapping the packer:

$packer = new Packer();
$packed = $packer->pack($file);
$minified = shell_exec("uglifyjs -c -m {$packed}");

Configuration Overrides Override default settings per environment (e.g., config/javascript-packer.php):
```
'production' => [
    'compression_level' => 9,
    'exclude_vars' => ['React', 'Vue'],
],
```

Javascript Packer Laravel Package