<?php

namespace cx_newsletter;
use \get_option;
use \update_option;
use \delete_option;
use \exception;

abstract class settings
implements settings_interface {
    public function __construct() {
        $this->is_initializated();
    }

    public abstract function get_plugin_version() : int;
    protected abstract function get_options() : array;

    public function get(string $name) : string {
        if (!$this->exists($name)) {
            throw $this->not_exists($name);
        }

        return get_option($this->esc_name($name), $this->get_default($name));
    }

    public function save(string $name, string $content) : self {
        if (!$this->exists($name)) {
            throw $this->not_exists($name);
        }

        update_option($this->esc_name($name), $content);

        return $this;
    }

    public function init() : void {
        foreach ($this->get_options_names() as $name) {
            $this->save($name, $this->get_default($name));
        }

        $this->set_initialization(true);
    }

    public function clean() : void {
        foreach ($this->get_options_names() as $name) {
            $this->drop($name);
        }

        $this->set_initialization(false);
    }       

    private function drop(string $name) : void {
        delete_option($this->esc_name($name));
    }

    public function get_default(string $name) : string {
        if (!$this->exists($name)) {
            throw $this->not_exists($name);
        }

        return $this->get_options()[$name];
    }

    private function get_options_names() : array {
        return array_keys($this->get_options());
    } 

    private function exists(string $name) : bool {
        return array_key_exists($name, $this->get_options()); 
    }

    private function not_exists(string $name) : \exception {
        return new exception('Setting with name '.$name.' not exists.');
    }

    private function esc_name(string $name) : string {
        return 'cx_newsletter_option_'.$name;
    }

    public function is_initializated() : bool {
        if ($this->initialization !== null) {
            return $this->initialization;
        }

        $state = get_option($this->initialization_name(), null);
        $this->initialization = ($state === 'yes');

        return $this->is_initializated();
    }

    private function set_initialization(bool $state) : void {
        update_option($this->initialization_name(), 'yes');
        $this->initialization = true;

        if (!$state) {
            delete_option($this->initialization_name());
            $this->initialization = false;
        }
    }

    private function initialization_name() : string {
        return 'cx_newsletter_options_initialization';
    }
    
    protected array $options;
    protected ?bool $initialization = null;
}