<?php
/*
 * This file is part of Fenom.
 *
 * (c) 2013 Ivan Shalganov
 *
 * For the full copyright and license information, please view the license.md
 * file that was distributed with this source code.
 */
use Fenom\ProviderInterface;
use Fenom\Template;

/**
 * Fenom Template Engine
 *
 * @author     Ivan Shalganov <a.cobest@gmail.com>
 */
class Fenom
{
    const VERSION = '1.4';

    /* Actions */
    const INLINE_COMPILER = 1;
    const BLOCK_COMPILER = 2;
    const INLINE_FUNCTION = 3;
    const BLOCK_FUNCTION = 4;
    const MODIFIER = 5;

    /* Options */
    const DENY_ACCESSOR = 0x8;
    const DENY_METHODS = 0x10;
    const DENY_NATIVE_FUNCS = 0x20;
    const FORCE_INCLUDE = 0x40;
    const AUTO_RELOAD = 0x80;
    const FORCE_COMPILE = 0x100;
    const AUTO_ESCAPE = 0x200;
    const DISABLE_CACHE = 0x400;
    const FORCE_VERIFY = 0x800;
    const AUTO_TRIM = 0x1000; // reserved
    const DENY_STATICS = 0x2000; // reserved

    /* @deprecated */
    const DENY_INLINE_FUNCS = 0x20;

    /* Default parsers */
    const DEFAULT_CLOSE_COMPILER = 'Fenom\Compiler::stdClose';
    const DEFAULT_FUNC_PARSER = 'Fenom\Compiler::stdFuncParser';
    const DEFAULT_FUNC_OPEN = 'Fenom\Compiler::stdFuncOpen';
    const DEFAULT_FUNC_CLOSE = 'Fenom\Compiler::stdFuncClose';
    const SMART_FUNC_PARSER = 'Fenom\Compiler::smartFuncParser';

    const MAX_MACRO_RECURSIVE = 32;

    /**
     * @var int[] of possible options, as associative array
     * @see setOptions
     */
    private static $_options_list = array(
        "disable_accessor" => self::DENY_ACCESSOR,
        "disable_methods" => self::DENY_METHODS,
        "disable_native_funcs" => self::DENY_NATIVE_FUNCS,
        "disable_cache" => self::DISABLE_CACHE,
        "force_compile" => self::FORCE_COMPILE,
        "auto_reload" => self::AUTO_RELOAD,
        "force_include" => self::FORCE_INCLUDE,
        "auto_escape" => self::AUTO_ESCAPE,
        "force_verify" => self::FORCE_VERIFY,
        "auto_trim" => self::AUTO_TRIM,
        "disable_statics" => self::DENY_STATICS,
    );

    /**
     * @var callable[]
     */
    public $pre_filters = array();

    /**
     * @var callable[]
     */
    public $filters = array();

    /**
     * @var callable[]
     */
    public $post_filters = array();

    /**
     * @var Fenom\Render[] Templates storage
     */
    protected $_storage = array();

    /**
     * @var string compile directory
     */
    protected $_compile_dir = "/tmp";

    /**
     * @var int masked options
     */
    protected $_options = 0;

    /**
     * @var ProviderInterface
     */
    private $_provider;
    /**
     * @var Fenom\ProviderInterface[]
     */
    protected $_providers = array();

    /**
     * @var string[] list of modifiers [modifier_name => callable]
     */
    protected $_modifiers = array(
        "upper" => 'strtoupper',
        "up" => 'strtoupper',
        "lower" => 'strtolower',
        "low" => 'strtolower',
        "date_format" => 'Fenom\Modifier::dateFormat',
        "date" => 'Fenom\Modifier::date',
        "truncate" => 'Fenom\Modifier::truncate',
        "escape" => 'Fenom\Modifier::escape',
        "e" => 'Fenom\Modifier::escape', // alias of escape
        "unescape" => 'Fenom\Modifier::unescape',
        "strip" => 'Fenom\Modifier::strip',
        "length" => 'Fenom\Modifier::length',
        "iterable" => 'Fenom\Modifier::isIterable'
    );

    /**
     * @var array of allowed PHP functions
     */
    protected $_allowed_funcs = array(
        "count" => 1, "is_string" => 1, "is_array" => 1, "is_numeric" => 1, "is_int" => 1, 'constant' => 1,
        "is_object" => 1, "strtotime" => 1, "gettype" => 1, "is_double" => 1, "json_encode" => 1, "json_decode" => 1,
        "ip2long" => 1, "long2ip" => 1, "strip_tags" => 1, "nl2br" => 1, "explode" => 1, "implode" => 1
    );

    /**
     * @var array[] of compilers and functions
     */
    protected $_actions = array(
        'foreach' => array( // {foreach ...} {break} {continue} {foreachelse} {/foreach}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::foreachOpen',
            'close' => 'Fenom\Compiler::foreachClose',
            'tags' => array(
                'foreachelse' => 'Fenom\Compiler::foreachElse',
                'break' => 'Fenom\Compiler::tagBreak',
                'continue' => 'Fenom\Compiler::tagContinue',
            ),
            'float_tags' => array('break' => 1, 'continue' => 1)
        ),
        'if' => array( // {if ...} {elseif ...} {else} {/if}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::ifOpen',
            'close' => 'Fenom\Compiler::stdClose',
            'tags' => array(
                'elseif' => 'Fenom\Compiler::tagElseIf',
                'else' => 'Fenom\Compiler::tagElse'
            )
        ),
        'switch' => array( // {switch ...} {case ..., ...}  {default} {/switch}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::switchOpen',
            'close' => 'Fenom\Compiler::switchClose',
            'tags' => array(
                'case' => 'Fenom\Compiler::tagCase',
                'default' => 'Fenom\Compiler::tagDefault'
            ),
            'float_tags' => array('break' => 1)
        ),
        'for' => array( // {for ...} {break} {continue} {/for}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::forOpen',
            'close' => 'Fenom\Compiler::forClose',
            'tags' => array(
                'forelse' => 'Fenom\Compiler::forElse',
                'break' => 'Fenom\Compiler::tagBreak',
                'continue' => 'Fenom\Compiler::tagContinue',
            ),
            'float_tags' => array('break' => 1, 'continue' => 1)
        ),
        'while' => array( // {while ...} {break} {continue} {/while}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::whileOpen',
            'close' => 'Fenom\Compiler::stdClose',
            'tags' => array(
                'break' => 'Fenom\Compiler::tagBreak',
                'continue' => 'Fenom\Compiler::tagContinue',
            ),
            'float_tags' => array('break' => 1, 'continue' => 1)
        ),
        'include' => array( // {include ...}
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagInclude'
        ),
        'insert' => array( // {include ...}
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagInsert'
        ),
        'var' => array( // {var ...}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::varOpen',
            'close' => 'Fenom\Compiler::varClose'
        ),
        'block' => array( // {block ...} {parent} {/block}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::tagBlockOpen',
            'close' => 'Fenom\Compiler::tagBlockClose',
            'tags' => array(//                'parent' => 'Fenom\Compiler::tagParent' // not implemented yet
            ),
            'float_tags' => array('parent' => 1)
        ),
        'extends' => array( // {extends ...}
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagExtends'
        ),
        'use' => array( // {use}
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagUse'
        ),
        'filter' => array( // {filter} ... {/filter}
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::filterOpen',
            'close' => 'Fenom\Compiler::filterClose'
        ),
        'macro' => array(
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::macroOpen',
            'close' => 'Fenom\Compiler::macroClose'
        ),
        'import' => array(
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagImport'
        ),
        'cycle' => array(
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagCycle'
        ),
        'raw' => array(
            'type' => self::INLINE_COMPILER,
            'parser' => 'Fenom\Compiler::tagRaw'
        ),
        'autoescape' => array(
            'type' => self::BLOCK_COMPILER,
            'open' => 'Fenom\Compiler::autoescapeOpen',
            'close' => 'Fenom\Compiler::autoescapeClose'
        )
    );

    /**
     * Just factory
     *
     * @param string|Fenom\ProviderInterface $source path to templates or custom provider
     * @param string $compile_dir path to compiled files
     * @param int $options
     * @throws InvalidArgumentException
     * @return Fenom
     */
    public static function factory($source, $compile_dir = '/tmp', $options = 0)
    {
        if (is_string($source)) {
            $provider = new Fenom\Provider($source);
        } elseif ($source instanceof ProviderInterface) {
            $provider = $source;
        } else {
            throw new InvalidArgumentException("Source must be a valid path or provider object");
        }
        $fenom = new static($provider);
        /* @var Fenom $fenom */
        $fenom->setCompileDir($compile_dir);
        if ($options) {
            $fenom->setOptions($options);
        }
        return $fenom;
    }

    /**
     * @param Fenom\ProviderInterface $provider
     */
    public function __construct(Fenom\ProviderInterface $provider)
    {
        $this->_provider = $provider;
    }

    /**
     * Set compile directory
     *
     * @param string $dir directory to store compiled templates in
     * @throws LogicException
     * @return Fenom
     */
    public function setCompileDir($dir)
    {
        if(!is_writable($dir)) {
            throw new LogicException("Cache directory $dir is not writable");
        }
        $this->_compile_dir = $dir;
        return $this;
    }

    /**
     *
     * @param callable $cb
     * @return self
     */
    public function addPreFilter($cb)
    {
        $this->pre_filters[] = $cb;
        return $this;
    }

    public function getPreFilters()
    {
        return $this->pre_filters;
    }

    /**
     *
     * @param callable $cb
     * @return self
     */
    public function addPostFilter($cb)
    {
        $this->post_filters[] = $cb;
        return $this;
    }


    public function getPostFilters()
    {
        return $this->post_filters;
    }

    /**
     * @param callable $cb
     * @return self
     */
    public function addFilter($cb)
    {
        $this->filters[] = $cb;
        return $this;
    }


    public function getFilters()
    {
        return $this->filters;
    }

    /**
     * Add modifier
     *
     * @param string $modifier the modifier name
     * @param string $callback the modifier callback
     * @return Fenom
     */
    public function addModifier($modifier, $callback)
    {
        $this->_modifiers[$modifier] = $callback;
        return $this;
    }

    /**
     * Add inline tag compiler
     *
     * @param string $compiler
     * @param callable $parser
     * @return Fenom
     */
    public function addCompiler($compiler, $parser)
    {
        $this->_actions[$compiler] = array(
            'type' => self::INLINE_COMPILER,
            'parser' => $parser
        );
        return $this;
    }

    /**
     * @param string $compiler
     * @param string|object $storage
     * @return $this
     */
    public function addCompilerSmart($compiler, $storage)
    {
        if (method_exists($storage, "tag" . $compiler)) {
            $this->_actions[$compiler] = array(
                'type' => self::INLINE_COMPILER,
                'parser' => array($storage, "tag" . $compiler)
            );
        }
        return $this;
    }

    /**
     * Add block compiler
     *
     * @param string $compiler
     * @param callable $open_parser
     * @param callable|string $close_parser
     * @param array $tags
     * @return Fenom
     */
    public function addBlockCompiler($compiler, $open_parser, $close_parser = self::DEFAULT_CLOSE_COMPILER, array $tags = array())
    {
        $this->_actions[$compiler] = array(
            'type' => self::BLOCK_COMPILER,
            'open' => $open_parser,
            'close' => $close_parser ? : self::DEFAULT_CLOSE_COMPILER,
            'tags' => $tags,
        );
        return $this;
    }

    /**
     * @param $compiler
     * @param $storage
     * @param array $tags
     * @param array $floats
     * @throws LogicException
     * @return Fenom
     */
    public function addBlockCompilerSmart($compiler, $storage, array $tags, array $floats = array())
    {
        $c = array(
            'type' => self::BLOCK_COMPILER,
            "tags" => array(),
            "float_tags" => array()
        );
        if (method_exists($storage, $compiler . "Open")) {
            $c["open"] = array($storage, $compiler . "Open");
        } else {
            throw new \LogicException("Open compiler {$compiler}Open not found");
        }
        if (method_exists($storage, $compiler . "Close")) {
            $c["close"] = array($storage, $compiler . "Close");
        } else {
            throw new \LogicException("Close compiler {$compiler}Close not found");
        }
        foreach ($tags as $tag) {
            if (method_exists($storage, "tag" . $tag)) {
                $c["tags"][$tag] = array($storage, "tag" . $tag);
                if ($floats && in_array($tag, $floats)) {
                    $c['float_tags'][$tag] = 1;
                }
            } else {
                throw new \LogicException("Tag compiler $tag (tag{$compiler}) not found");
            }
        }
        $this->_actions[$compiler] = $c;
        return $this;
    }

    /**
     * @param string $function
     * @param callable $callback
     * @param callable|string $parser
     * @return Fenom
     */
    public function addFunction($function, $callback, $parser = self::DEFAULT_FUNC_PARSER)
    {
        $this->_actions[$function] = array(
            'type' => self::INLINE_FUNCTION,
            'parser' => $parser,
            'function' => $callback,
        );
        return $this;
    }

    /**
     * @param string $function
     * @param callable $callback
     * @return Fenom
     */
    public function addFunctionSmart($function, $callback)
    {
        $this->_actions[$function] = array(
            'type' => self::INLINE_FUNCTION,
            'parser' => self::SMART_FUNC_PARSER,
            'function' => $callback,
        );
        return $this;
    }

    /**
     * @param string $function
     * @param callable $callback
     * @param callable|string $parser_open
     * @param callable|string $parser_close
     * @return Fenom
     */
    public function addBlockFunction($function, $callback, $parser_open = self::DEFAULT_FUNC_OPEN, $parser_close = self::DEFAULT_FUNC_CLOSE)
    {
        $this->_actions[$function] = array(
            'type' => self::BLOCK_FUNCTION,
            'open' => $parser_open,
            'close' => $parser_close,
            'function' => $callback,
        );
        return $this;
    }

    /**
     * @param array $funcs
     * @return Fenom
     */
    public function addAllowedFunctions(array $funcs)
    {
        $this->_allowed_funcs = $this->_allowed_funcs + array_flip($funcs);
        return $this;
    }

    /**
     * Return modifier function
     *
     * @param string $modifier
     * @param Fenom\Template $template
     * @return mixed
     */
    public function getModifier($modifier, Template $template = null)
    {
        if (isset($this->_modifiers[$modifier])) {
            return $this->_modifiers[$modifier];
        } elseif ($this->isAllowedFunction($modifier)) {
            return $modifier;
        } else {
            return $this->_loadModifier($modifier, $template);
        }
    }

    /**
     * @param string $modifier
     * @param Fenom\Template $template
     * @return bool
     */
    protected function _loadModifier($modifier, $template)
    {
        return false;
    }

    /**
     * Returns tag info
     *
     * @param string $tag
     * @param Fenom\Template $template
     * @return string|bool
     */
    public function getTag($tag, Template $template = null)
    {
        if (isset($this->_actions[$tag])) {
            return $this->_actions[$tag];
        } else {
            return $this->_loadTag($tag, $template);
        }
    }

    /**
     * @param $tag
     * @param Fenom\Template $template
     * @return bool
     */
    protected function _loadTag($tag, $template)
    {
        return false;
    }

    /**
     * @param string $function
     * @return bool
     */
    public function isAllowedFunction($function)
    {
        if ($this->_options & self::DENY_NATIVE_FUNCS) {
            return isset($this->_allowed_funcs[$function]);
        } else {
            return is_callable($function);
        }
    }

    /**
     * @param string $tag
     * @return array
     */
    public function getTagOwners($tag)
    {
        $tags = array();
        foreach ($this->_actions as $owner => $params) {
            if (isset($params["tags"][$tag])) {
                $tags[] = $owner;
            }
        }
        return $tags;
    }

    /**
     * Add source template provider by scheme
     *
     * @param string $scm scheme name
     * @param Fenom\ProviderInterface $provider provider object
     * @return $this
     */
    public function addProvider($scm, \Fenom\ProviderInterface $provider)
    {
        $this->_providers[$scm] = $provider;
        return $this;
    }

    /**
     * Set options
     * @param int|array $options
     * @return $this
     */
    public function setOptions($options)
    {
        if (is_array($options)) {
            $options = self::_makeMask($options, self::$_options_list, $this->_options);
        }
        $this->_storage = array();
        $this->_options = $options;
        return $this;
    }

    /**
     * Get options as bits
     * @return int
     */
    public function getOptions()
    {
        return $this->_options;
    }

    /**
     * @param bool|string $scm
     * @return Fenom\ProviderInterface
     * @throws InvalidArgumentException
     */
    public function getProvider($scm = false)
    {
        if ($scm) {
            if (isset($this->_providers[$scm])) {
                return $this->_providers[$scm];
            } else {
                throw new InvalidArgumentException("Provider for '$scm' not found");
            }
        } else {
            return $this->_provider;
        }
    }

    /**
     * Return empty template
     *
     * @return Fenom\Template
     */
    public function getRawTemplate()
    {
        return new Template($this, $this->_options);
    }

    /**
     * Execute template and write result into stdout
     *
     * @param string $template name of template
     * @param array $vars array of data for template
     * @return Fenom\Render
     */
    public function display($template, array $vars = array())
    {
        return $this->getTemplate($template)->display($vars);
    }

    /**
     *
     * @param string $template name of template
     * @param array $vars array of data for template
     * @return mixed
     */
    public function fetch($template, array $vars = array())
    {
        return $this->getTemplate($template)->fetch($vars);
    }

    /**
     *
     *
     * @param string $template name of template
     * @param array $vars
     * @param callable $callback
     * @param float $chunk
     * @return array
     */
    public function pipe($template, $callback, array $vars = array(), $chunk = 1e6)
    {
        ob_start($callback, $chunk, true);
        $data = $this->getTemplate($template)->display($vars);
        ob_end_flush();
        return $data;
    }

    /**
     * Get template by name
     *
     * @param string $template template name with schema
     * @param int $options additional options and flags
     * @return Fenom\Template
     */
    public function getTemplate($template, $options = 0)
    {
        $options |= $this->_options;
        $key = dechex($options) . "@" . $template;
        if (isset($this->_storage[$key])) {
            /** @var Fenom\Template $tpl */
            $tpl = $this->_storage[$key];
            if (($this->_options & self::AUTO_RELOAD) && !$tpl->isValid()) {
                return $this->_storage[$key] = $this->compile($template, true, $options);
            } else {
                return $tpl;
            }
        } elseif ($this->_options & self::FORCE_COMPILE) {
            return $this->compile($template, $this->_options & self::DISABLE_CACHE & ~self::FORCE_COMPILE, $options);
        } else {
            return $this->_storage[$key] = $this->_load($template, $options);
        }
    }

    /**
     * Check if template exists
     * @param string $template
     * @return bool
     */
    public function templateExists($template)
    {
        if ($provider = strstr($template, ":", true)) {
            if (isset($this->_providers[$provider])) {
                return $this->_providers[$provider]->templateExists(substr($template, strlen($provider) + 1));
            }
        } else {
            return $this->_provider->templateExists($template);
        }
        return false;
    }

    /**
     * Load template from cache or create cache if it doesn't exists.
     *
     * @param string $tpl
     * @param int $opts
     * @return Fenom\Render
     */
    protected function _load($tpl, $opts)
    {
        $file_name = $this->_getCacheName($tpl, $opts);
        if (is_file($this->_compile_dir . "/" . $file_name)) {
            $fenom = $this; // used in template
            $_tpl = include($this->_compile_dir . "/" . $file_name);
            /* @var Fenom\Render $_tpl */
            if (!($this->_options & self::AUTO_RELOAD) || ($this->_options & self::AUTO_RELOAD) && $_tpl->isValid()) {
                return $_tpl;
            }
        }
        return $this->compile($tpl, true, $opts);
    }

    /**
     * Generate unique name of compiled template
     *
     * @param string $tpl
     * @param int $options
     * @return string
     */
    private function _getCacheName($tpl, $options)
    {
        $hash = $tpl . ":" . $options;
        return sprintf("%s.%x.%x.php", str_replace(":", "_", basename($tpl)), crc32($hash), strlen($hash));
    }

    /**
     * Compile and save template
     *
     * @param string $tpl
     * @param bool $store store template on disk
     * @param int $options
     * @throws RuntimeException
     * @return \Fenom\Template
     */
    public function compile($tpl, $store = true, $options = 0)
    {
        $options = $this->_options | $options;
        $template = $this->getRawTemplate()->load($tpl);
        if ($store) {
            $cache = $this->_getCacheName($tpl, $options);
            $tpl_tmp = tempnam($this->_compile_dir, $cache);
            $tpl_fp = fopen($tpl_tmp, "w");
            if (!$tpl_fp) {
                throw new \RuntimeException("Can't to open temporary file $tpl_tmp. Directory " . $this->_compile_dir . " is writable?");
            }
            fwrite($tpl_fp, $template->getTemplateCode());
            fclose($tpl_fp);
            $file_name = $this->_compile_dir . "/" . $cache;
            if (!rename($tpl_tmp, $file_name)) {
                throw new \RuntimeException("Can't to move $tpl_tmp to $file_name");
            }
        }
        return $template;
    }

    /**
     * Flush internal memory template cache
     */
    public function flush()
    {
        $this->_storage = array();
    }

    /**
     * Remove all compiled templates
     */
    public function clearAllCompiles()
    {
        \Fenom\Provider::clean($this->_compile_dir);
    }

    /**
     * Compile code to template
     *
     * @param string $code
     * @param string $name
     * @return Fenom\Template
     */
    public function compileCode($code, $name = 'Runtime compile')
    {
        return $this->getRawTemplate()->source($name, $code);
    }


    /**
     * Create bit-mask from associative array use fully associative array possible keys with bit values
     * @static
     * @param array $values custom assoc array, ["a" => true, "b" => false]
     * @param array $options possible values, ["a" => 0b001, "b" => 0b010, "c" => 0b100]
     * @param int $mask the initial value of the mask
     * @return int result, ( $mask | a ) & ~b
     * @throws \RuntimeException if key from custom assoc doesn't exists into possible values
     */
    private static function _makeMask(array $values, array $options, $mask = 0)
    {
        foreach ($values as $key => $value) {
            if (isset($options[$key])) {
                if ($value) {
                    $mask |= $options[$key];
                } else {
                    $mask &= ~$options[$key];
                }
            } else {
                throw new \RuntimeException("Undefined parameter $value");
            }
        }
        return $mask;
    }
}