<?php

class ClientScriptManager extends TClientScriptManager {

    private $_page;
    public function __construct(TPage $page) {
        $this->_page = $page;
        parent::__construct($page);
    }

    private function _getBasePath() {
        $assetManager = $this->Application->AssetManager;
        return preg_replace(
            '#' . preg_quote($assetManager->BaseUrl) . '$#',
            '',
            $assetManager->BasePath
        );
    }

    private function _getBasePaths($urls) {
        $basePath = $this->_getBasePath();
        return array_map(
            function($path) use($basePath) {
                return $basePath . DIRECTORY_SEPARATOR . $path;
            },
            $urls
        );
    }

    private function _getCachePath($subdir = 'assets') {
        $cachePath = $this->Application->RuntimePath
            . DIRECTORY_SEPARATOR
            . $subdir;
        if (!is_dir($cachePath)) {
            if (file_exists($cachePath)) {
                throw new TIOException(
                    'Client script manager cache path "'
                    . $cachePath
                    . ' "exists and is not a directory'
                );
            } else {
                mkdir($cachePath);
            }
        }
        return $cachePath;
    }

    private function _getCacheFilePath($path, $type) {
        return $this->_getCachePath($type)
            . DIRECTORY_SEPARATOR
            . $path;
    }

    private function _getFileCollectionCacheKey($files) {
        sort($files);
        return md5(implode(PHP_EOL, $files));
    }

    private function _getFileCollectionMTime($files) {
        return max(array_map('filemtime', $files));
    }

    private $_renderedScriptsInitialized = FALSE;

    private function _getRenderedScripts() {
        if ($this->_page->IsCallBack || $this->_renderedScriptsInitialized) {
            return $this->Session->itemAt('RenderedScripts') ?: [];
        } else {
            $this->Session->remove('RenderedScripts');
            $this->_renderedScriptsInitialized = TRUE;
            return [];
        }
    }

    private function _appendRenderedScripts(array $newScripts, $compiledFileKey) {
        $scripts = $this->_getRenderedScripts();
        if (!isset($scripts[$compiledFileKey])) {
            $scripts[$compiledFileKey] = [];
        }
        $scripts[$compiledFileKey] = array_unique(
            array_merge(
                $scripts[$compiledFileKey],
                $newScripts
            )
        );
        $this->Session->add('RenderedScripts', $scripts);
    }

    private function _compileFiles($files) {
        foreach ($files as $file) {
            $this->markScriptFileAsRendered($file);
        }
        $paths = $this->_getBasePaths($files);
        $cacheKey = $this->_getFileCollectionCacheKey($paths);
        $cacheFile = $this->_getCacheFilePath($cacheKey . '.js', 'scripts');
        $this->_appendRenderedScripts($files, $cacheFile);
        if (!file_exists($cacheFile)
            || (filemtime($cacheFile)
                < $this->_getFileCollectionMTime($paths))) {
            $scriptContent = implode(
                PHP_EOL,
                array_map('file_get_contents', $paths)
            );
            file_put_contents($cacheFile, $scriptContent);
        }
        return $this->Application->AssetManager->publishFilePath($cacheFile);
    }

    private function _determineLocalScriptFiles($files) {
        $basePath = $this->_getBasePath();
        return array_filter(
            $files,
            function($file) use($basePath) {
                return file_exists($basePath . DIRECTORY_SEPARATOR . $file);
            }
        );
    }

    private function _renderLocalScriptFiles($writer, $localFiles) {
        if ($localFiles) {
            $assetPath = $this->_compileFiles($localFiles);
            $writer->write(TJavascript::renderScriptFile($assetPath));
        }
    }

    private function _renderExternalScriptFiles($writer, $externalFiles) {
        if ($externalFiles) {
            foreach ($externalFiles as $file) {
                $this->markScriptFileAsRendered($file);
                $this->_appendRenderedScripts([$file], $file);
            }
            parent::renderScriptFiles($writer, $externalFiles);
        }
    }

    public function renderScriptFiles($writer, Array $files) {
        if ($this->getApplication()->getMode() !== TApplicationMode::Debug) {
            if ($files) {
                $localFiles = $this->_determineLocalScriptFiles($files);
                $this->_renderLocalScriptFiles($writer, $localFiles);
                $externalFiles = array_diff($files, $localFiles);
                $this->_renderExternalScriptFiles($writer, $externalFiles);
            }
        } else {
            parent::renderScriptFiles($writer, $files);
        }
    }

    private function _getRenderedScriptUrl($registeredScript) {
        $renderedScripts = $this->_getRenderedScripts();
        foreach ($renderedScripts as $compiledFile => $scripts) {
            if (in_array($registeredScript, $scripts)) {
                if (file_exists($compiledFile)) {
                    return $this->Application->AssetManager->getPublishedUrl(
                        $compiledFile
                    );
                } else {
                    return $registeredScript;
                }
            }
        }
        return FALSE;
    }

    public function getScriptUrls() {
        if ($this->getApplication()->getMode() !== TApplicationMode::Debug) {
            $registeredScripts = array_unique(
                array_merge(
                    $this->_scripts, $this->_headScripts
                )
            );
            $scriptUrls = [];
            $newScripts = [];
            foreach ($registeredScripts as $registeredScript) {
                $renderedScriptUrl = $this->_getRenderedScriptUrl(
                    $registeredScript
                );
                if ($renderedScriptUrl) {
                    $scriptUrls[] = $renderedScriptUrl;
                } else {
                    $newScripts[] = $registeredScript;
                }
            }
            $newLocalScripts = $this->_determineLocalScriptFiles($newScripts);
            $newRemoteScripts = array_diff($newScripts, $newLocalScripts);
            if ($newLocalScripts) {
                $scriptUrls[] = $this->_compileFiles($newLocalScripts);
            }
            $scriptUrls = array_values(
                array_unique(array_merge($scriptUrls, $newRemoteScripts))
            );
            return $scriptUrls;
        } else {
            return parent::getScriptUrls();
        }
    }

    private $_scripts = [];
    private $_headScripts = [];

    public function registerScriptFile($key, $file) {
        $this->_scripts[$key] = $file;
        return parent::registerScriptFile($key, $file);
    }

    public function registerHeadScriptFile($key, $file) {
        $this->_headScripts[$key] = $file;
        return parent::registerHeadScriptFile($key, $file);
    }

}

?>