<?php
namespace ProVM\Common\Alias;

use \Model as BaseModel;
use ProVM\Common\Define\Model as ModelInterface;
use ProVM\Common\Factory\Model as ModelFactory;

abstract class Model extends BaseModel implements ModelInterface {
  const SELF_KEY = 'self_key';
  const PARENT_KEY = 'parent_key';
  const CHILD_KEY = 'child_key';
  const SIBLING_KEY = 'sibling_key';
  const SELF_CONNECT_KEY = 'self_connect_key';
  const SIBLING_CONNECT_KEY = 'sibling_connect_key';

  public function getTable(): string {
    return static::$_table;
  }

  protected $factory;
  public function setFactory(ModelFactory $factory): ModelInterface {
    $this->factory = $factory;
    return $this;
  }

  protected function checkDefinitions(array $definitions, array $required, array $default) {
    foreach ($default as $key => $value) {
      if (!isset($definitions[$key])) {
        $definitions[$key] = $value;
      }
    }
    foreach ($required as $definition) {
      if (!isset($definitions[$definition])) {
        $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 1);
        throw new \InvalidArgumentException($definition . ' is required for ' . $trace[1]['function'] . ' in ' . get_called_class());
      }
    }
    return $definitions;
  }
  public function parentOf(string $child_model_class, array $relation_definitions): ?array {
    $relation_definitions = $this->checkDefinitions($relation_definitions, [
      Model::SELF_KEY,
      Model::CHILD_KEY
    ], [
      Model::SELF_KEY => 'id'
    ]);
    return $this->factory
      ->find($child_model_class)
      ->where([
        [
          $relation_definitions[Model::CHILD_KEY],
          $this->{$relation_definitions[Model::SELF_KEY]}
        ]
      ])
      ->many();
  }
  public function childOf(string $parent_model_class, array $relation_definitions): ?ModelInterface {
    $relation_definitions = $this->checkDefinitions($relation_definitions, [
      Model::SELF_KEY,
      Model::PARENT_KEY
    ], [
      Model::PARENT_KEY => 'id'
    ]);
    $parent_table = (new $parent_model_class())->getTable();
    return $this->factory
      ->find($parent_model_class)
      ->where([
        [
          $relation_definitions[Model::PARENT_KEY],
          $this->{$relation_definitions[Model::SELF_KEY]}
        ]
      ])
      ->one();
  }
  public function siblingOf(string $sibling_model_class, string $connecting_table, array $relation_definitions): ?array {
    $relation_definitions = $this->checkDefinitions($relation_definitions, [
      Model::SELF_KEY,
      Model::SIBLING_KEY,
      Model::SELF_CONNECT_KEY,
      Model::SIBLING_CONNECT_KEY
    ], [
      Model::SELF_KEY => 'id',
      Model::SIBLING_KEY => 'id'
    ]);
    $sibling_table = (new $sibling_model_class())->getTable();
    return $this->find($sibling_model_class)
      ->select([
        [
          $sibling_table,
          '*'
        ],
        [
          $connecting_table,
          '*'
        ]
      ])
      ->join([
        [
          $connecting_table,
          implode('.', [
            $connecting_table,
            $relation_definitions[Model::SIBLING_CONNECT_KEY]
          ]),
          implode('.', [
            $sibling_table,
            $relation_definitions[Model::SIBLING_KEY]
          ])
        ]
      ])
      ->where([
        [
          implode('.', [
            $connecting_table,
            $relation_definitions[Model::SELF_CONNECT_KEY]
          ]),
          $this->{$relation_definitions[Model::SELF_KEY]}
        ]
      ])
      ->many();
  }

  public function toArray(): array {
    return $this->asArray();
  }

  protected static function parseInput($input): array {
    return array_intersect_key((array) $input, array_combine(static::$fields, static::$fields));
  }
  public static function add(ModelFactory $factory, $input): ?ModelInterface {
    $data = static::parseInput($input);
    $class = get_called_class();
    if (method_exists($class, 'find')) {
      $obj = static::find($factory, $input);
    } else {
      $where = $data;
      array_walk($where, function(&$item, $key) {
        $item = [$key, $item];
      });
      $where = array_values($where);
      $obj = $factory->find($class)->where($where)->one();
    }
    if ($obj === null) {
      $obj = $factory->create($class, $data);
    }
    return $obj;
  }
  public function edit($input): bool {
    $data = static::parseInput($input);
    foreach (static::$fields as $field) {
      if ($this->{$field} != $data[$field]) {
        $this->{$field} = $data[$field];
      }
    }
    return $this->save();
  }
}