<?php

class ModelCode extends CCodeModel
{
	public $connectionId = 'db';
	public $tablePrefix;
	public $tableName;
	public $modelClass;
	public $modelPath = 'application.models';
	public $baseClass = 'CActiveRecord';
	public $buildRelations = true;
	public $commentsAsLabels = false;

	/**
	 * @var array list of candidate relation code. The array are indexed by AR class names and relation names.
	 * Each element represents the code of the one relation in one AR class.
	 */
	protected $relations;

	public function rules()
	{
		return array_merge(parent::rules(), array(
			array('tablePrefix, baseClass, tableName, modelClass, modelPath, connectionId', 'filter', 'filter' => 'trim'),
			array('connectionId, tableName, modelPath, baseClass', 'required'),
			array('tablePrefix, tableName, modelPath', 'match', 'pattern' => '/^(\w+[\w\.]*|\*?|\w+\.\*)$/', 'message' => '{attribute} should only contain word characters, dots, and an optional ending asterisk.'),
			array('connectionId', 'validateConnectionId', 'skipOnError' => true),
			array('tableName', 'validateTableName', 'skipOnError' => true),
			array('tablePrefix, modelClass', 'match', 'pattern' => '/^[a-zA-Z_]\w*$/', 'message' => '{attribute} should only contain word characters.'),
			array('baseClass', 'match', 'pattern' => '/^[a-zA-Z_\\\\][\w\\\\]*$/', 'message' => '{attribute} should only contain word characters and backslashes.'),
			array('modelPath', 'validateModelPath', 'skipOnError' => true),
			array('baseClass, modelClass', 'validateReservedWord', 'skipOnError' => true),
			array('baseClass', 'validateBaseClass', 'skipOnError' => true),
			array('connectionId, tablePrefix, modelPath, baseClass, buildRelations, commentsAsLabels', 'sticky'),
		));
	}

	public function attributeLabels()
	{
		return array_merge(parent::attributeLabels(), array(
			'tablePrefix' => 'Table Prefix',
			'tableName' => 'Table Name',
			'modelPath' => 'Model Path',
			'modelClass' => 'Model Class',
			'baseClass' => 'Base Class',
			'buildRelations' => 'Build Relations',
			'commentsAsLabels' => 'Use Column Comments as Attribute Labels',
			'connectionId' => 'Database Connection',
		));
	}

	public function requiredTemplates()
	{
		return array(
			'model.php',
		);
	}

	public function init()
	{
		if (Yii::app()->{$this->connectionId} === null)
			throw new CHttpException(500, 'A valid database connection is required to run this generator.');
		$this->tablePrefix = Yii::app()->{$this->connectionId}->tablePrefix;
		parent::init();
	}

	public function prepare()
	{
		if (($pos = strrpos($this->tableName, '.')) !== false) {
			$schema = substr($this->tableName, 0, $pos);
			$tableName = substr($this->tableName, $pos + 1);
		} else {
			$schema = '';
			$tableName = $this->tableName;
		}
		if ($tableName[strlen($tableName) - 1] === '*') {
			$tables = Yii::app()->{$this->connectionId}->schema->getTables($schema);
			if ($this->tablePrefix != '') {
				foreach ($tables as $i => $table) {
					if (strpos($table->name, $this->tablePrefix) !== 0)
						unset($tables[$i]);
				}
			}
		} else
			$tables = array($this->getTableSchema($this->tableName));

		$this->files = array();
		$templatePath = $this->templatePath;
		$this->relations = $this->generateRelations();

		foreach ($tables as $table) {
			$tableName = $this->removePrefix($table->name);
			$className = $this->generateClassName($table->name);
			$params = array(
				'tableName' => $schema === '' ? $tableName : $schema . '.' . $tableName,
				'modelClass' => $className,
				'columns' => $table->columns,
				'labels' => $this->generateLabels($table),
				'rules' => $this->generateRules($table),
				'relations' => isset($this->relations[$className]) ? $this->relations[$className] : array(),
				'connectionId' => $this->connectionId,
			);
			$this->files[] = new CCodeFile(
				Yii::getPathOfAlias($this->modelPath) . '/' . $className . '.php',
				$this->render($templatePath . '/model.php', $params)
			);
		}
	}

	public function validateTableName($attribute, $params)
	{
		if ($this->hasErrors())
			return;

		$invalidTables = array();
		$invalidColumns = array();

		if ($this->tableName[strlen($this->tableName) - 1] === '*') {
			if (($pos = strrpos($this->tableName, '.')) !== false)
				$schema = substr($this->tableName, 0, $pos);
			else
				$schema = '';

			$this->modelClass = '';
			$tables = Yii::app()->{$this->connectionId}->schema->getTables($schema);
			foreach ($tables as $table) {
				if ($this->tablePrefix == '' || strpos($table->name, $this->tablePrefix) === 0) {
					if (in_array(strtolower($table->name), self::$keywords))
						$invalidTables[] = $table->name;
					if (($invalidColumn = $this->checkColumns($table)) !== null)
						$invalidColumns[] = $invalidColumn;
				}
			}
		} else {
			if (($table = $this->getTableSchema($this->tableName)) === null)
				$this->addError('tableName', "Table '{$this->tableName}' does not exist.");
			if ($this->modelClass === '')
				$this->addError('modelClass', 'Model Class cannot be blank.');

			if (!$this->hasErrors($attribute) && ($invalidColumn = $this->checkColumns($table)) !== null)
				$invalidColumns[] = $invalidColumn;
		}

		if ($invalidTables != array())
			$this->addError('tableName', 'Model class cannot take a reserved PHP keyword! Table name: ' . implode(', ', $invalidTables) . ".");
		if ($invalidColumns != array())
			$this->addError('tableName', 'Column names that does not follow PHP variable naming convention: ' . implode(', ', $invalidColumns) . ".");
	}

	/*
	 * Check that all database field names conform to PHP variable naming rules
	 * For example mysql allows field name like "2011aa", but PHP does not allow variable like "$model->2011aa"
	 * @param CDbTableSchema $table the table schema object
	 * @return string the invalid table column name. Null if no error.
	 */
	public function checkColumns($table)
	{
		foreach ($table->columns as $column) {
			if (!preg_match('/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*$/', $column->name))
				return $table->name . '.' . $column->name;
		}
	}

	public function validateModelPath($attribute, $params)
	{
		if (Yii::getPathOfAlias($this->modelPath) === false)
			$this->addError('modelPath', 'Model Path must be a valid path alias.');
	}

	public function validateBaseClass($attribute, $params)
	{
		$class = @Yii::import($this->baseClass, true);
		if (!is_string($class) || !$this->classExists($class))
			$this->addError('baseClass', "Class '{$this->baseClass}' does not exist or has syntax error.");
		elseif ($class !== 'CActiveRecord' && !is_subclass_of($class, 'CActiveRecord'))
			$this->addError('baseClass', "'{$this->baseClass}' must extend from CActiveRecord.");
	}

	public function getTableSchema($tableName)
	{
		$connection = Yii::app()->{$this->connectionId};
		return $connection->getSchema()->getTable($tableName, $connection->schemaCachingDuration !== 0);
	}

	public function generateLabels($table)
	{
		$labels = array();
		foreach ($table->columns as $column) {
			if ($this->commentsAsLabels && $column->comment)
				$labels[$column->name] = $column->comment;
			else {
				$label = ucwords(trim(strtolower(str_replace(array('-', '_'), ' ', preg_replace('/(?<![A-Z])[A-Z]/', ' \0', $column->name)))));
				$label = preg_replace('/\s+/', ' ', $label);
				if (strcasecmp(substr($label, -3), ' id') === 0)
					$label = substr($label, 0, -3);
				if ($label === 'Id')
					$label = 'ID';
				$label = str_replace("'", "\\'", $label);
				$labels[$column->name] = $label;
			}
		}
		return $labels;
	}

	public function generateRules($table)
	{
		$rules = array();
		$required = array();
		$integers = array();
		$numerical = array();
		$length = array();
		$safe = array();
		foreach ($table->columns as $column) {
			if ($column->autoIncrement)
				continue;
			$r = !$column->allowNull && $column->defaultValue === null;
			if ($r)
				$required[] = $column->name;
			if ($column->type === 'integer')
				$integers[] = $column->name;
			elseif ($column->type === 'double')
				$numerical[] = $column->name;
			elseif ($column->type === 'string' && $column->size > 0)
				$length[$column->size][] = $column->name;
			elseif (!$column->isPrimaryKey && !$r)
				$safe[] = $column->name;
		}
		if ($required !== array())
			$rules[] = "array('" . implode(', ', $required) . "', 'required')";
		if ($integers !== array())
			$rules[] = "array('" . implode(', ', $integers) . "', 'numerical', 'integerOnly'=>true)";
		if ($numerical !== array())
			$rules[] = "array('" . implode(', ', $numerical) . "', 'numerical')";
		if ($length !== array()) {
			foreach ($length as $len => $cols)
				$rules[] = "array('" . implode(', ', $cols) . "', 'length', 'max'=>$len)";
		}
		if ($safe !== array())
			$rules[] = "array('" . implode(', ', $safe) . "', 'safe')";

		return $rules;
	}

	public function getRelations($className)
	{
		return isset($this->relations[$className]) ? $this->relations[$className] : array();
	}

	protected function removePrefix($tableName, $addBrackets = true)
	{
		if ($addBrackets && Yii::app()->{$this->connectionId}->tablePrefix == '')
			return $tableName;
		$prefix = $this->tablePrefix != '' ? $this->tablePrefix : Yii::app()->{$this->connectionId}->tablePrefix;
		if ($prefix != '') {
			if ($addBrackets && Yii::app()->{$this->connectionId}->tablePrefix != '') {
				$prefix = Yii::app()->{$this->connectionId}->tablePrefix;
				$lb = '{{';
				$rb = '}}';
			} else
				$lb = $rb = '';
			if (($pos = strrpos($tableName, '.')) !== false) {
				$schema = substr($tableName, 0, $pos);
				$name = substr($tableName, $pos + 1);
				if (strpos($name, $prefix) === 0)
					return $schema . '.' . $lb . substr($name, strlen($prefix)) . $rb;
			} elseif (strpos($tableName, $prefix) === 0)
				return $lb . substr($tableName, strlen($prefix)) . $rb;
		}
		return $tableName;
	}

	protected function generateRelations()
	{
		if (!$this->buildRelations)
			return array();

		$schemaName = '';
		if (($pos = strpos($this->tableName, '.')) !== false)
			$schemaName = substr($this->tableName, 0, $pos);

		$relations = array();
		foreach (Yii::app()->{$this->connectionId}->schema->getTables($schemaName) as $table) {
			if ($this->tablePrefix != '' && strpos($table->name, $this->tablePrefix) !== 0)
				continue;
			$tableName = $table->name;

			if ($this->isRelationTable($table)) {
				$pks = $table->primaryKey;
				$fks = $table->foreignKeys;

				$table0 = $fks[$pks[0]][0];
				$table1 = $fks[$pks[1]][0];
				$className0 = $this->generateClassName($table0);
				$className1 = $this->generateClassName($table1);

				$unprefixedTableName = $this->removePrefix($tableName);

				$relationName = $this->generateRelationName($table0, $table1, true);
				$relations[$className0][$relationName] = "array(self::MANY_MANY, '$className1', '$unprefixedTableName($pks[0], $pks[1])')";

				$relationName = $this->generateRelationName($table1, $table0, true);

				$i = 1;
				$rawName = $relationName;
				while (isset($relations[$className1][$relationName]))
					$relationName = $rawName . $i++;

				$relations[$className1][$relationName] = "array(self::MANY_MANY, '$className0', '$unprefixedTableName($pks[1], $pks[0])')";
			} else {
				$className = $this->generateClassName($tableName);
				foreach ($table->foreignKeys as $fkName => $fkEntry) {
					// Put table and key name in variables for easier reading
					$refTable = $fkEntry[0]; // Table name that current fk references to
					$refKey = $fkEntry[1];   // Key in that table being referenced
					$refClassName = $this->generateClassName($refTable);

					// Add relation for this table
					$relationName = $this->generateRelationName($tableName, $fkName, false);
					$relations[$className][$relationName] = "array(self::BELONGS_TO, '$refClassName', '$fkName')";

					// Add relation for the referenced table
					$relationType = $table->primaryKey === $fkName ? 'HAS_ONE' : 'HAS_MANY';
					$relationName = $this->generateRelationName($refTable, $this->removePrefix($tableName, false), $relationType === 'HAS_MANY');
					$i = 1;
					$rawName = $relationName;
					while (isset($relations[$refClassName][$relationName]))
						$relationName = $rawName . ($i++);
					$relations[$refClassName][$relationName] = "array(self::$relationType, '$className', '$fkName')";
				}
			}
		}
		return $relations;
	}

	/**
	 * Checks if the given table is a "many to many" pivot table.
	 * Their PK has 2 fields, and both of those fields are also FK to other separate tables.
	 * @param CDbTableSchema table to inspect
	 * @return boolean true if table matches description of helper table.
	 */
	protected function isRelationTable($table)
	{
		$pk = $table->primaryKey;
		$count = is_array($pk) ? count($pk) : 1;
		return ($count === 2 // we want 2 columns
			&& isset($table->foreignKeys[$pk[0]]) // pk column 1 is also a foreign key
			&& isset($table->foreignKeys[$pk[1]]) // pk column 2 is also a foriegn key
			&& $table->foreignKeys[$pk[0]][0] !== $table->foreignKeys[$pk[1]][0]); // and the foreign keys point different tables
	}

	protected function generateClassName($tableName)
	{
		if ($this->tableName === $tableName || ($pos = strrpos($this->tableName, '.')) !== false && substr($this->tableName, $pos + 1) === $tableName)
			return $this->modelClass;

		$tableName = $this->removePrefix($tableName, false);
		if (($pos = strpos($tableName, '.')) !== false) // remove schema part (e.g. remove 'public2.' from 'public2.post')
			$tableName = substr($tableName, $pos + 1);
		$className = '';
		foreach (explode('_', $tableName) as $name) {
			if ($name !== '')
				$className .= ucfirst($name);
		}
		return $className;
	}

	/**
	 * Generate a name for use as a relation name (inside relations() function in a model).
	 * @param string the name of the table to hold the relation
	 * @param string the foreign key name
	 * @param boolean whether the relation would contain multiple objects
	 * @return string the relation name
	 */
	protected function generateRelationName($tableName, $fkName, $multiple)
	{
		if (strcasecmp(substr($fkName, -2), 'id') === 0 && strcasecmp($fkName, 'id'))
			$relationName = rtrim(substr($fkName, 0, -2), '_');
		else
			$relationName = $fkName;
		// $rName = $relationName;
		// $relationName = [];
		$relationName = strtolower($relationName);

		if ($multiple)
			$relationName = $this->pluralize($relationName);

		$names = preg_split('/_+/', $relationName, -1, PREG_SPLIT_NO_EMPTY);
		if (empty($names)) return $relationName;  // unlikely
		for ($name = $names[0], $i = 1; $i < count($names); ++$i)
			$name .= ucfirst($names[$i]);

		$rawName = $name;
		$table = Yii::app()->{$this->connectionId}->schema->getTable($tableName);
		$i = 0;
		while (isset($table->columns[$name]))
			$name = $rawName . ($i++);

		return $name;
	}

	public function validateConnectionId($attribute, $params)
	{
		if (Yii::app()->hasComponent($this->connectionId) === false || !(Yii::app()->getComponent($this->connectionId) instanceof CDbConnection))
			$this->addError('connectionId', 'A valid database connection is required to run this generator.');
	}
}
