<?php

/**
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; under version 2
 * of the License (non-upgradable).
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2015 (original work) Open Assessment Technologies SA (under the project TAO-PRODUCT);
 *
 */

namespace oat\tao\model;

use common_ext_ExtensionsManager;
use oat\oatbox\AbstractRegistry;
use oat\oatbox\service\ServiceManager;
use oat\tao\model\asset\AssetService;
use oat\tao\model\websource\WebsourceManager;

class ThemeRegistry extends AbstractRegistry
{

    const WEBSOURCE = 'websource_';

    /**
     *
     * @see \oat\oatbox\AbstractRegistry::getExtension()
     */
    protected function getExtension()
    {
        return common_ext_ExtensionsManager::singleton()->getExtensionById('tao');
    }

    /**
     *
     * @see \oat\oatbox\AbstractRegistry::getConfigId()
     */
    protected function getConfigId()
    {
        return 'themes';
    }


    public function setWebSource($websource)
    {
        $this->set(ThemeRegistry::WEBSOURCE, $websource);
    }


    /**
     *
     * @author Lionel Lecaque, lionel@taotesting.com
     * @param string $target
     * @param string $themeId
     * @throws \common_Exception
     */
    public function setDefaultTheme($target, $themeId)
    {
        $theme = $this->getTheme($target, $themeId);
        if (!is_null($theme)) {
            $array = $this->get($target);
            $array['default'] = $themeId;
            $this->set($target, $array);
        }
    }

    /**
     * Get the theme array identified by its target and id
     *
     * @param string $target
     * @param string $themeId
     * @return array
     * @throws \common_Exception
     */
    private function getTheme($target, $themeId)
    {

        $returnValue = null;
        if (!$this->isRegistered($target)) {
            throw new \common_Exception('Target ' . $target . ' does not exist');
        } else {
            $array = $this->get($target);
            $found = false;
            foreach ($array['available'] as $theme) {
                if ($theme['id'] == $themeId) {
                    $found = true;
                    $returnValue = $theme;
                    break;
                }
            }
            if (!$found) {
                throw new ThemeNotFoundException('Theme ' . $themeId . ' not found for target ' . $target);
            }
        }
        return $returnValue;
    }

    /**
     * Get the default theme array
     */
    public function getDefaultTheme($target)
    {
        $defaultTheme = null;
        if (!$this->isRegistered($target)) {
            throw new \common_Exception('Target ' . $target . ' does not exist');
        } else {
            $array = $this->get($target);
            if (isset($array['default'])) {
                $themeId = $array['default'];
                try {
                    $defaultTheme = $this->getTheme($target, $themeId);
                } catch (Exception $e) {
                    //not found
                    $defaultTheme = null;
                }
            }
        }
        return $defaultTheme;
    }

    /**
     * Adds a new target to the System
     *
     * @param string $targetId
     * @param string|array $base
     * @throws \common_Exception
     */
    public function createTarget($targetId, $base)
    {

        if (!is_string($base) && !is_array($base)) {
            throw new \common_Exception('Invalid base format');
        }

        $array = [
            'base'  => $base,
            'available' => []
        ];
        $this->set($targetId, $array);
    }


    /**
     * Adds a theme to the registry
     *
     * @author Lionel Lecaque, lionel@taotesting.com
     * @param string $id
     * @param string $name
     * @param string $path
     * @param array $targets
     * @throws \common_Exception
     */
    public function registerTheme($id, $name, $path = '', $targets = [], $templates = [])
    {
        if (preg_match('/^[a-zA-Z0-9]*$/', $id) === 0) {
            throw new \common_Exception('Invalid id "' . $id . '"');
        }
        if (!is_array($targets) || count($targets) === 0) {
            throw new \common_Exception('No targets were provided for theme ' . $id);
        }

        foreach ($targets as $target) {
            if (!$this->isRegistered($target)) {
                throw new \common_Exception('Target ' . $target . ' does not exist');
            } else {
                $array = $this->get($target);

                foreach ($array['available'] as $theme) {
                    if ($theme['id'] == $id) {
                        throw new \common_Exception('Theme ' . $id . ' already exists for target ' . $target);
                    }
                }

                $theme = [
                    'id' => $id,
                    'name' => $name
                ];

                //the path is optional
                if ($path) {
                    $theme['path'] = $path;
                }

                //register templates
                if (is_array($templates) && count($templates) > 0) {
                    $theme['templates'] = [];
                    foreach ($templates as $templateId => $tpl) {
                        $theme['templates'][$templateId] = $tpl;
                    }
                }

                $array['available'][] = $theme;
            }
            $this->set($target, $array);
        }
    }

    /**
     *
     * @author Joel Bout, joel@taotesting.com
     *
     * @param string $id
     * @throws \common_Exception
     */
    public function unregisterTheme($id)
    {
        if (preg_match('/^[a-zA-Z0-9]*$/', $id) === 0) {
            throw new \common_Exception('Invalid id "' . $id . '"');
        }

        $isDeleted = false;

        $map = $this->getMap();
        unset($map[ThemeRegistry::WEBSOURCE]);//still ugly but looks better than 'continue'
        foreach ($map as $target => $themes) {
            foreach ($themes['available'] as $key => $theme) {
                if ($theme['id'] == $id) {
                    unset($themes['available'][$key]);
                    $isDeleted = true;
                }
            }
            $this->set($target, $themes);
        }

        if (!$isDeleted) {
            throw new ThemeNotFoundException('Theme ' . $id . ' not found for any target');
        }
    }

    /**
     * @param $theme
     * @return mixed
     */
    private function updatePath($theme)
    {

        if (isset($theme['path'])) {
            if (strpos($theme['path'], ThemeRegistry::WEBSOURCE) === 0) {
                $websource = WebsourceManager::singleton()->getWebsource($this->get(ThemeRegistry::WEBSOURCE));
                $webUrl = $websource->getAccessUrl(substr($theme['path'], strlen(ThemeRegistry::WEBSOURCE)));
                $theme['path'] = $webUrl;
            } else {
                $assetService = $this->getServiceManager()->get(AssetService::SERVICE_ID);
                $theme['path'] = $assetService->getAsset($theme['path']);
            }
        }

        return $theme;
    }

    /**
     * Get the resolved absolute URL for a stylesheet
     *
     * @param string $path
     * @return string
     */
    private function resolveStylesheetUrl($path)
    {
        $websource = WebsourceManager::singleton()->getWebsource($this->get(ThemeRegistry::WEBSOURCE));
        if (strpos($path, ThemeRegistry::WEBSOURCE) === 0) {
                return $websource->getAccessUrl(substr($path, strlen(ThemeRegistry::WEBSOURCE)));
        } else {
            $assetService = $this->getServiceManager()->get(AssetService::SERVICE_ID);
            return $assetService->getAsset($path);
        }
    }

    /**
     * Resolve the template absolute path
     *
     * @todo make it support templates as data
     * @param string $tpl
     * @return string
     */
    private function resolveTemplatePath($tpl)
    {
        return ROOT_PATH . $tpl;
    }

    /**
     * Resolve the path and url defined in target "base"
     *
     * @param string $target
     * @return mixed
     * @throws common_Exception
     */
    private function getResolvedBase($target)
    {

        $base = null;
        $array = $this->get($target);

        if (is_string($array['base'])) {
            $assetService = $this->getServiceManager()->get(AssetService::SERVICE_ID);
            $base = $assetService->getAsset($array['base']);
        } elseif (is_array($array['base'])) {
            $base = [
                'css' => $this->resolveStylesheetUrl($array['base']['css']),
                'templates' => []
            ];

            foreach ($array['base']['templates'] as $id => $path) {
                $base['templates'][$id] = $this->resolveTemplatePath($path);
            }
        } else {
            throw new common_Exception('invalid type for theme base');
        }

        return $base;
    }

    /**
     * Get list of available theme
     * The available themes have their URL and paths resolved
     *
     * @author Lionel Lecaque, lionel@taotesting.com
     */
    public function getAvailableThemes()
    {

        $returnValue = [];
        foreach ($this->getMap() as $target => $value) {
            //ugly
            if ($target == ThemeRegistry::WEBSOURCE) {
                continue;
            }
            //retrieve all other value
            $returnValue[$target] = $value;

            // adapt path for all theme
            $returnValue[$target]['available'] = [];
            foreach ($value['available'] as $theme) {
                $returnValue[$target]['available'][] = $this->updatePath($theme);
            }

            $returnValue[$target]['base'] = $this->getResolvedBase($target);
        }
        return $returnValue;
    }

    /**
     * Get the absolute path to a theme template
     *
     * @deprecated use theme\ThemeService instead
     * @param string $target
     * @param string $themeId
     * @param string $templateId
     * @return string
     */
    public function getTemplate($target, $themeId, $templateId)
    {
        $theme = $this->getTheme($target, $themeId);
        if (isset($theme['templates']) && isset($theme['templates'][$templateId])) {
            return $this->resolveTemplatePath($theme['templates'][$templateId]);
        }
        return null;
    }

    /**
     * Get the abosolute url to a stylesheet
     *
     * @deprecated use theme\ThemeService instead
     * @param string $target
     * @param string $themeId
     * @return string
     */
    public function getStylesheet($target, $themeId)
    {
        $theme = $this->getTheme($target, $themeId);
        if (isset($theme['path'])) {
            return $this->resolveStylesheetUrl($theme['path']);
        }
        return null;//not found
    }

    /**
     * Get the asbolute path to the base template
     *
     * @deprecated use theme\ThemeService instead
     * @param string $target
     * @param string $templateId
     * @return string
     */
    public function getBaseTemplate($target, $templateId)
    {
        $base = $this->getResolvedBase($target);
        if (is_array($base) && isset($base['templates']) && isset($base['templates'][$templateId])) {
            return $base['templates'][$templateId];
        }
        return null;
    }

    /**
     * Get the absolute url to the base css
     *
     * @deprecated use theme\ThemeService instead
     * @param string $target
     * @return string
     */
    public function getBaseStylesheet($target)
    {
        $base = $this->getResolvedBase($target);
        if (is_string($base)) {
            return $base;
        } elseif (is_array($base) && isset($base['css'])) {
            return $base['css'];
        }
        return null;
    }

    public function getServiceManager()
    {
        return ServiceManager::getServiceManager();
    }
}