<?php
namespace Kant\Filesystem;

use ErrorException;
use FilesystemIterator;
use Symfony\Component\Finder\Finder;
use Kant\Http\File\Exception\FileNotFoundException;

class Filesystem
{

    /**
     * Determine if a file or directory exists.
     *
     * @param string $path            
     * @return bool
     */
    public function exists($path)
    {
        return file_exists($path);
    }

    /**
     * Get the contents of a file.
     *
     * @param string $path            
     * @param bool $lock            
     * @return string
     *
     * @throws \Kant\Http\File\Exception\FileNotFoundException
     */
    public function get($path, $lock = false)
    {
        if ($this->isFile($path)) {
            return $lock ? $this->sharedGet($path) : file_get_contents($path);
        }
        
        throw new FileNotFoundException("File does not exist at path {$path}");
    }

    /**
     * Get contents of a file with shared access.
     *
     * @param string $path            
     * @return string
     */
    public function sharedGet($path)
    {
        $contents = '';
        
        $handle = fopen($path, 'rb');
        
        if ($handle) {
            try {
                if (flock($handle, LOCK_SH)) {
                    clearstatcache(true, $path);
                    
                    $contents = fread($handle, $this->size($path) ?  : 1);
                    
                    flock($handle, LOCK_UN);
                }
            } finally {
                fclose($handle);
            }
        }
        
        return $contents;
    }

    /**
     * Get the returned value of a file.
     *
     * @param string $path            
     * @return mixed
     *
     * @throws \Kant\Http\File\Exception\FileNotFoundException
     */
    public function getRequire($path)
    {
        if ($this->isFile($path)) {
            return require $path;
        }
        
        throw new FileNotFoundException("File does not exist at path {$path}");
    }

    /**
     * Require the given file once.
     *
     * @param string $file            
     * @return mixed
     */
    public function requireOnce($file)
    {
        require_once $file;
    }

    /**
     * Write the contents of a file.
     *
     * @param string $path            
     * @param string $contents            
     * @param bool $lock            
     * @return int
     */
    public function put($path, $contents, $lock = false)
    {
        return file_put_contents($path, $contents, $lock ? LOCK_EX : 0);
    }

    /**
     * Prepend to a file.
     *
     * @param string $path            
     * @param string $data            
     * @return int
     */
    public function prepend($path, $data)
    {
        if ($this->exists($path)) {
            return $this->put($path, $data . $this->get($path));
        }
        
        return $this->put($path, $data);
    }

    /**
     * Append to a file.
     *
     * @param string $path            
     * @param string $data            
     * @return int
     */
    public function append($path, $data)
    {
        return file_put_contents($path, $data, FILE_APPEND);
    }

    /**
     * Delete the file at a given path.
     *
     * @param string|array $paths            
     * @return bool
     */
    public function delete($paths)
    {
        $paths = is_array($paths) ? $paths : func_get_args();
        
        $success = true;
        
        foreach ($paths as $path) {
            try {
                if (!@unlink($path)) {
                    $success = false;
                }
            } catch (ErrorException $e) {
                $success = false;
            }
        }
        
        return $success;
    }

    /**
     * Move a file to a new location.
     *
     * @param string $path            
     * @param string $target            
     * @return bool
     */
    public function move($path, $target)
    {
        return rename($path, $target);
    }

    /**
     * Copy a file to a new location.
     *
     * @param string $path            
     * @param string $target            
     * @return bool
     */
    public function copy($path, $target)
    {
        return copy($path, $target);
    }

    /**
     * Extract the file name from a file path.
     *
     * @param string $path            
     * @return string
     */
    public function name($path)
    {
        return pathinfo($path, PATHINFO_FILENAME);
    }

    /**
     * Extract the trailing name component from a file path.
     *
     * @param string $path            
     * @return string
     */
    public function basename($path)
    {
        return pathinfo($path, PATHINFO_BASENAME);
    }

    /**
     * Extract the parent directory from a file path.
     *
     * @param string $path            
     * @return string
     */
    public function dirname($path)
    {
        return pathinfo($path, PATHINFO_DIRNAME);
    }

    /**
     * Extract the file extension from a file path.
     *
     * @param string $path            
     * @return string
     */
    public function extension($path)
    {
        return pathinfo($path, PATHINFO_EXTENSION);
    }

    /**
     * Get the file type of a given file.
     *
     * @param string $path            
     * @return string
     */
    public function type($path)
    {
        return filetype($path);
    }

    /**
     * Get the mime-type of a given file.
     *
     * @param string $path            
     * @return string|false
     */
    public function mimeType($path)
    {
        return finfo_file(finfo_open(FILEINFO_MIME_TYPE), $path);
    }

    /**
     * Get the file size of a given file.
     *
     * @param string $path            
     * @return int
     */
    public function size($path)
    {
        return filesize($path);
    }

    /**
     * Get the file's last modification time.
     *
     * @param string $path            
     * @return int
     */
    public function lastModified($path)
    {
        return filemtime($path);
    }

    /**
     * Determine if the given path is a directory.
     *
     * @param string $directory            
     * @return bool
     */
    public function isDirectory($directory)
    {
        return is_dir($directory);
    }

    /**
     * Determine if the given path is writable.
     *
     * @param string $path            
     * @return bool
     */
    public function isWritable($path)
    {
        return is_writable($path);
    }

    /**
     * Determine if the given path is a file.
     *
     * @param string $file            
     * @return bool
     */
    public function isFile($file)
    {
        return is_file($file);
    }

    /**
     * Find path names matching a given pattern.
     *
     * @param string $pattern            
     * @param int $flags            
     * @return array
     */
    public function glob($pattern, $flags = 0)
    {
        return glob($pattern, $flags);
    }

    /**
     * Get an array of all files in a directory.
     *
     * @param string $directory            
     * @return array
     */
    public function files($directory)
    {
        $glob = glob($directory . '/*');
        
        if ($glob === false) {
            return [];
        }
        
        // To get the appropriate files, we'll simply glob the directory and filter
        // out any "files" that are not truly files so we do not end up with any
        // directories in our list, but only true files within the directory.
        return array_filter($glob, function ($file) {
            return filetype($file) == 'file';
        });
    }

    /**
     * Get all of the files from the given directory (recursive).
     *
     * @param string $directory            
     * @param bool $hidden            
     * @return array
     */
    public function allFiles($directory, $hidden = false)
    {
        return iterator_to_array(Finder::create()->files()
            ->ignoreDotFiles(!$hidden)
            ->in($directory), false);
    }

    /**
     * Get all of the directories within a given directory.
     *
     * @param string $directory            
     * @return array
     */
    public function directories($directory)
    {
        $directories = [];
        
        foreach (Finder::create()->in($directory)
            ->directories()
            ->depth(0) as $dir) {
            $directories[] = $dir->getPathname();
        }
        
        return $directories;
    }

    /**
     * Create a directory.
     *
     * @param string $path            
     * @param int $mode            
     * @param bool $recursive            
     * @param bool $force            
     * @return bool
     */
    public function makeDirectory($path, $mode = 0755, $recursive = false, $force = false)
    {
        if ($force) {
            return @mkdir($path, $mode, $recursive);
        }
        
        return mkdir($path, $mode, $recursive);
    }

    /**
     * Move a directory.
     *
     * @param string $from            
     * @param string $to            
     * @param bool $overwrite            
     * @return bool
     */
    public function moveDirectory($from, $to, $overwrite = false)
    {
        if ($overwrite && $this->isDirectory($to)) {
            if (!$this->deleteDirectory($to)) {
                return false;
            }
        }
        
        return @rename($from, $to) === true;
    }

    /**
     * Copy a directory from one location to another.
     *
     * @param string $directory            
     * @param string $destination            
     * @param int $options            
     * @return bool
     */
    public function copyDirectory($directory, $destination, $options = null)
    {
        if (!$this->isDirectory($directory)) {
            return false;
        }
        
        $options = $options ?  : FilesystemIterator::SKIP_DOTS;
        
        // If the destination directory does not actually exist, we will go ahead and
        // create it recursively, which just gets the destination prepared to copy
        // the files over. Once we make the directory we'll proceed the copying.
        if (!$this->isDirectory($destination)) {
            $this->makeDirectory($destination, 0777, true);
        }
        
        $items = new FilesystemIterator($directory, $options);
        
        foreach ($items as $item) {
            // As we spin through items, we will check to see if the current file is actually
            // a directory or a file. When it is actually a directory we will need to call
            // back into this function recursively to keep copying these nested folders.
            $target = $destination . '/' . $item->getBasename();
            
            if ($item->isDir()) {
                $path = $item->getPathname();
                
                if (!$this->copyDirectory($path, $target, $options)) {
                    return false;
                }
            }             

            // If the current items is just a regular file, we will just copy this to the new
            // location and keep looping. If for some reason the copy fails we'll bail out
            // and return false, so the developer is aware that the copy process failed.
            else {
                if (!$this->copy($item->getPathname(), $target)) {
                    return false;
                }
            }
        }
        
        return true;
    }

    /**
     * Recursively delete a directory.
     *
     * The directory itself may be optionally preserved.
     *
     * @param string $directory            
     * @param bool $preserve            
     * @return bool
     */
    public function deleteDirectory($directory, $preserve = false)
    {
        if (!$this->isDirectory($directory)) {
            return false;
        }
        
        $items = new FilesystemIterator($directory);
        
        foreach ($items as $item) {
            // If the item is a directory, we can just recurse into the function and
            // delete that sub-directory otherwise we'll just delete the file and
            // keep iterating through each file until the directory is cleaned.
            if ($item->isDir() && ! $item->isLink()) {
                $this->deleteDirectory($item->getPathname());
            }             

            // If the item is just a file, we can go ahead and delete it since we're
            // just looping through and waxing all of the files in this directory
            // and calling directories recursively, so we delete the real path.
            else {
                $this->delete($item->getPathname());
            }
        }
        
        if (!$preserve) {
            @rmdir($directory);
        }
        
        return true;
    }

    /**
     * Empty the specified directory of all files and folders.
     *
     * @param string $directory            
     * @return bool
     */
    public function cleanDirectory($directory)
    {
        return $this->deleteDirectory($directory, true);
    }

    /**
     * Clean the specified directory by file modify time.
     *
     * The directory itself may be optionally preserved.
     *
     * @param string $directory            
     * @param bool $preserve            
     * @return bool
     */
    public function cleanDirectoryByFilemtime($directory, $expire)
    {
        if (!$this->isDirectory($directory)) {
            return false;
        }
        
        $items = new FilesystemIterator($directory);
        
        foreach ($items as $item) {
            // If the item is a directory, we can just recurse into the function and
            // delete that sub-directory otherwise we'll just delete the file and
            // keep iterating through each file until the directory is cleaned.
            if ($item->isDir() && ! $item->isLink()) {
                $this->cleanDirectoryByFilemtime($item->getPathname(), $expire);
            }             

            // If the item is just a file, we can go ahead and delete it since we're
            // just looping through and waxing all of the files in this directory
            // and calling directories recursively, so we delete the real path.
            else {
                if ($item->getMTime() < $_SERVER['REQUEST_TIME'] - $expire) {
                    $this->delete($item->getPathname());
                }
            }
        }
        
        return true;
    }
}
