<?php

/**
 * DomFramework
 * @package domframework
 * @author Dominique Fournier <dominique@fournier38.fr>
 * @license BSD
 */

namespace Domframework;

/**
 * The rate limit with file storage
 */
class Ratelimitfile extends Ratelimit
{
    /**
     * The storage directory
     */
    public $storageDir = "data/ratelimit/";
    /**
     * Debug the ratelimiting process to screen
     */
    public $debug = false;

    /**
     * The function set a rate-limit
     * @param string $name The rate-limit object to set
     * @return bool true if the rate-limit is not overloaded
     *              false if the rate-limit is overloaded
     */
    public function set($name)
    {
        $this->storageOK();
        $nameFile = substr(rawurlencode($name), 0, 128);
        $file = $this->storageDir . "/$nameFile";
        // Add the current timestamp
        $currentTimeStamp = microtime(true) . "\n";
        if ($this->debug) {
            echo "Add entry : $currentTimeStamp";
        }
        $user = posix_getpwuid(posix_getuid());
        if (file_exists($file) && ! is_writeable($file)) {
            throw new \Exception(sprintf(
                dgettext(
                    "domframework",
                    "File '%s' not writeable for user '%s'"
                ),
                $file,
                $user["name"]
            ), 500);
        }
        file_put_contents($file, $currentTimeStamp, FILE_APPEND);
        $lock = new Lockfile();
        $lock->storagelock = $this->storageDir . "/lockfile.lock";
        $lock->lockRW();
        $contents = file($file);
        // Look if there is deprecated entries in the file
        foreach ($contents as $key => $content) {
            $content = rtrim($content);
            if ($content + $this->unittime < microtime(true)) {
                if ($this->debug) {
                    echo "Remove deprecated entry : $content\n";
                }
                unset($contents[$key]);
            } else {
                if ($this->debug) {
                    echo "Active entry : $content\n";
                }
            }
        }
        file_put_contents($file, $contents);
        $lock->unlockRW();
        unset($lock);
        $this->clean();
        if (count($contents) > $this->maxEntries) {
            if ($this->debug) {
                echo "Ratelimiting for '$name'\n";
            }
            return false;
        }
        return true;
    }

    /**
     * The function delete a rate-limit
     * @param string $name The rate-limit object to del
     * @return bool
     */
    public function del($name)
    {
        $this->storageOK();
        $nameFile = substr(rawurlencode($name), 0, 128);
        $file = $this->storageDir . "/$nameFile";
        if (file_exists($file)) {
            if ($this->debug) {
                echo "Removing the rate-limiting for '$name'\n";
            }
            unlink($file);
        }
        return true;
    }

    /**
     * The function clean the storage with expired entries
     * @return bool
     */
    public function clean()
    {
        $this->storageOK();
        $files = glob($this->storageDir . "/*");
        foreach ($files as $file) {
            if (filemtime($file) + $this->unittime < time()) {
                if ($this->debug) {
                    echo "Removing the deprecated rate-limiting for '" .
                    rawurldecode(basename($file)) . "'\n";
                }
                unlink($file);
            }
        }
        return true;
    }

    /**
     * Check the storageDir state
     */
    private function storageOK()
    {
        if (file_exists($this->storageDir)) {
            if (! is_dir($this->storageDir)) {
                throw new \Exception(sprintf(
                    dgettext(
                        "domframework",
                        "storageDir '%s' is not a directory"
                    ),
                    $this->storageDir
                ), 500);
            }
            if (! is_readable($this->storageDir)) {
                throw new \Exception(sprintf(
                    dgettext(
                        "domframework",
                        "storageDir '%s' is not readable"
                    ),
                    $this->storageDir
                ), 500);
            }
            if (! is_writeable($this->storageDir)) {
                throw new \Exception(sprintf(
                    dgettext(
                        "domframework",
                        "storageDir '%s' is not writeable"
                    ),
                    $this->storageDir
                ), 500);
            }
        } else {
            if (@mkdir($this->storageDir, 0777, true) === false) {
                throw new \Exception(sprintf(
                    dgettext(
                        "domframework",
                        "Can't create '%s' storageDir"
                    ),
                    $this->storageDir
                ), 500);
            }
        }
        return true;
    }
}