<?php

namespace Tell;

class I18n
{
    const DELIMITER = '.';

    protected bool $updatedData = false;

    protected array $data   = [];

    protected array $cache  = [];

    protected array $engine = [];

    protected string $currentLanguage = "";

    protected array $fileStack = [];

    protected function __construct(bool $enableCache = false) {

#        $this->persistent = new Persistent(static::class);
        if ( $enableCache ) {
#            $data = $this->persistent->load();
#            $this->data = $data['data'];
#            $this->fileStack = $data['fileStack'];
        }
    }

    public function __destruct() {
#        $this->update_data() && $this->persistent->save([
#            'fileStack' => $this->fileStack,
#            'data' => $this->data
#        ]);
    }

    public function updateData() {
        return $this->updatedData;
    }

    public static function get(?string $key = null) {
        if ( $key === null ) {
            return $this->data;
        }

        return isset( $this->cache[$key] ) ? $this->cache[$key] : $this->cache[$key] = Iterate::arrayGet($this->data, ( $this->currentLanguage ? $this->currentLanguage."." : "").$key, static::DELIMITER);
    }

    public static function set(string $key, $value) {
        $cache = explode(static::DELIMITER, $key);

        while ( !empty($cache) ) {
            $imp = implode(static::DELIMITER, $cache);
            array_pop($cache);
            unset( $this->cache[$imp] );
        }

        $this->cache[$key] = $value ;

        return Iterate::arraySet($this->data, $key, $value, static::DELIMITER);
    }

    public function addEngine($engine) {
        $this->engine[] = $engine;
    }

    public function load(string $path, bool $filenameAsKey = false) {
        if ( !in_array($path, $this->fileStack) ) {
            $this->updatedData = true;
            $this->fileStack[] = $path;

            foreach(Iterate::files($path) as $item) {
                 foreach($this->engine as $engine) {
                     if ( $engine->accept($item )) {

                         if ( $array = $engine->translate( $item ) ){
                             if ($filenameAsKey ) {
                                 $base = basename($item);

                                 $key = substr($base,0, strrpos($base, "."));
                                 $keysplit = explode(".", $key);
                                 $key = array_pop($keysplit);

                                 $this->mergeData([ $keysplit ? "{".implode(".", array_merge([ $key ], $keysplit))."}" : $key => $array ]);
                             }
                             else {
                                 $this->mergeData($array);
                             }
                         }

                         continue 2;
                     }
                 }
            }
        }
    }

    public static function currentLanguage($set = null) {
        return $set === null ? $this->currentLanguage : $this->currentLanguage = $set;
    }

    protected function mergeData($data) {
        $this->data = array_replace_recursive($this->data, Iterate::splitKeys($data));
    }
}