transact.php

<?php

class FatalException extends Exception {}

interface DesignFolderIf {
    public function getBasePath();
    public function getFiles();

}

interface PrototypeIf extends DesignFolderIf {
    public function createFork($uniqueKey);
}

class DesignFolder {
    private $basePath = NULL;
    private $files = NULL;

    public function __construct($base_path, $files) {
        $this->basePath = $base_path;
        $this->files = $files;
    }

    public function getBasePath() {
        return $this->basePath;
    }

    public function getFiles() {
        return $this->files;
    }

    public function cloneDirTo($uniqueKey) {
        $dirPath = $this->makeDir($uniqueKey);
        $this->copyFilesTo($dirPath);
        return $dirPath;
    }

    protected function makeDir($uniqueKey) {
        $dirPath = $this->getBasePath() . '/forks/' . $uniqueKey;
        if (!mkdir($dirPath, 0x0666)) {
            throw new Exception("Directory \"" . $uniqueKey . "\" cannot be created");
        }
        return $dirPath;
    }

    protected function copyFilesTo($dirPath) {
        foreach ($this->getFiles() as $file) {
            $source = $this->getBasePath() . '/' . $file;
            if (!copy($source, $dirPath . '/' . $file)) {
                /*if (!exec('rm -rf "' . $dirPath . '"')) {
                    throw new FatalException("Cannot remove directory \"{$dirPath}\" for roll back");
                }*/
                throw new Exception("Cannot copy file \"{$source}\" to directory \"{$dirPath}\"");
            }
        }
    }
}

class DesignPrototype extends DesignFolder
    implements PrototypeIf {

    public function createFork($uniqueKey) {
        $dirPath = $this->cloneDirTo($uniqueKey);
        return new DesignTransaction($dirPath, $this->getFiles());
    }

}

class DesignTransaction extends DesignFolder {
    private $uniqueKey = NULL;

    private function storeRef($uniqueKey) {

    }

    private function removeRef() {

    }

    public function createInstance() {
        $uniqueKey = time().rand(10000,99999);
        try {
            $newDirPath = $this->getBasePath() . '-' . $uniqueKey;
            $instance = new DesignInstance($this->getBasePath(), $this->getFiles());
            $dirPath = $instance->cloneDirTo($newDirPath);
            $instance = new DesignInstance($newDirPath, $this->getFiles());
            $this->storeRef($uniqueKey, $dirPath);
        } catch (Exception $e) {
            $this->removeRef($uniqueKey);
            throw $e;
        }
        return $instance;
    }

    public function commit() {

    }

    public function rollBack() {

    }
}

class DesignInstance extends DesignPrototype {

    public function getContent($fileName) {
        return file_get_contents($this->getBasePath() . '/' . $fileName);
    }

    public function setContent($fileName, $text) {
        file_put_contents($this->getBasePath() . '/' . $fileName, $text);
        return $this;
    }

    public function replaceFile($originFN, $fileKey) {
        if (unlink($this->getBasePath() . $originFN)) {

        }
    }

    public function resizeImage($fileName, $size) {
        $source = $this->getBasePath() . '/' . $fileName;
        $fn = pathinfo($fileName, PATHINFO_FILENAME);
        $ext = pathinfo($fileName, PATHINFO_EXTENSION);
        $cmd = 'convert "' . $source . '" -resize ' . $size .
                ' "' . $this->getBasePath() . '/' . $fn . '-' . $size . $ext . '"';
        exec($cmd, $output, $ret);
        if (intval($ret)) {
            throw new Exception("Cannot resize image file \"{$source}\"; "
                    . "command \"{$cmd}\"; output \"{$output}\"");
        }
    }

}

class DesignGroup {

    public function registerInstance(DesignInstance $instance) {

    }

}


// example

if (!empty($_POST)) {
    $prototype = new DesignPrototype(realpath(__DIR__ . '/../pretty_box'),
        array(
            'close.png',
            'box.css',
            'loading.gif',
            'warning.png',
        ));
}