<?php

namespace Icinga\Module\Director\CustomVariable;

use Icinga\Exception\ProgrammingError;

abstract class CustomVariable
{
    protected $key;

    protected $value;

    protected $storedValue;

    protected $type;

    protected $modified = false;

    protected function __construct($key, $value = null)
    {
        $this->key = $key;
        $this->setValue($value);
    }

    public function is($type)
    {
        return $this->getType() === $type;
    }

    public function getType()
    {
        if ($this->type === null) {
            $parts = explode('\\', get_class($this));
            $class = end($parts);
            // strlen('CustomVariable') === 9
            $this->type = substr(end($parts), 9);
        }

        return $this->type;
    }

    public function getKey()
    {
        return $this->key;
    }

    public function getValue()
    {
        return $this->value;
    }

    public function setValue($value)
    {
        if ($value instanceof CustomVariable) {
            if (! $this->equals($value)) {
                $this->reallySetValue($value);
            }
        } elseif ($value !== $this->value) {
            $this->reallySetValue($value);
        }

        return $this;
    }

    protected function reallySetValue($value)
    {
        $this->modified = true;
        $this->value = $value;
    }

    public function hasBeenModified()
    {
        return $this->modified;
    }

    public function setUnmodified()
    {
        $this->modified = false;
        $this->storedValue = clone($this->value);
        return $this;
    }

    abstract public function equals(CustomVariable $var);

    abstract public function toConfigString();

    public function differsFrom(CustomVariable $var)
    {
        return ! $this->equals($var);
    }

    public static function create($key, $value)
    {
        if (is_string($value)) {

            return new CustomVariableString($key, $value);

        } elseif (is_array($value)) {

            foreach (array_keys($value) as $key) {
                if (! is_int($key) || ctype_digit($key)) {
                    return new CustomVariableDictionary($key, $value);
                }
            }

            return new CustomVariableArray($key, array_values($value));

        } elseif (is_object($value)) {
            // TODO: check for specific class/stdClass/interface?
            return new CustomVariableDictionary($key, $value);

        } else {
            throw new ProgrammingError();
        }
    }

    public function __toString()
    {
        try {
            return $this->toConfigString();
        } catch (Exception $e) {
            trigger_error($e);
            $previousHandler = set_exception_handler(function () {});
            restore_error_handler();
            call_user_func($previousHandler, $e);
            die();
        }
    }
}