<?php
/**
 * @link http://www.yiiframework.com/
 * @copyright Copyright (c) 2008 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace yii\db\mssql;

use yii\base\InvalidParamException;

/**
 * QueryBuilder is the query builder for MS SQL Server databases (version 2008 and above).
 *
 * @author Timur Ruziev <resurtm@gmail.com>
 * @since 2.0
 */
class QueryBuilder extends \yii\db\QueryBuilder
{
    /**
     * @var array mapping from abstract column types (keys) to physical column types (values).
     */
    public $typeMap = [
        Schema::TYPE_PK => 'int IDENTITY PRIMARY KEY',
        Schema::TYPE_BIGPK => 'bigint IDENTITY PRIMARY KEY',
        Schema::TYPE_STRING => 'varchar(255)',
        Schema::TYPE_TEXT => 'text',
        Schema::TYPE_SMALLINT => 'smallint',
        Schema::TYPE_INTEGER => 'int',
        Schema::TYPE_BIGINT => 'bigint',
        Schema::TYPE_FLOAT => 'float',
        Schema::TYPE_DECIMAL => 'decimal',
        Schema::TYPE_DATETIME => 'datetime',
        Schema::TYPE_TIMESTAMP => 'timestamp',
        Schema::TYPE_TIME => 'time',
        Schema::TYPE_DATE => 'date',
        Schema::TYPE_BINARY => 'binary',
        Schema::TYPE_BOOLEAN => 'bit',
        Schema::TYPE_MONEY => 'decimal(19,4)',
    ];

//	public function update($table, $columns, $condition, &$params)
//	{
//		return '';
//	}

//	public function delete($table, $condition, &$params)
//	{
//		return '';
//	}

    /**
     * @param  integer $limit
     * @param  integer $offset
     * @return string  the LIMIT and OFFSET clauses built from [[\yii\db\Query::$limit]].
     */
    public function buildLimit($limit, $offset = 0)
    {
        $hasOffset = $this->hasOffset($offset);
        $hasLimit = $this->hasLimit($limit);
        if ($hasOffset || $hasLimit) {
            // http://technet.microsoft.com/en-us/library/gg699618.aspx
            $sql = 'OFFSET ' . ($hasOffset ? $offset : '0');
            if ($hasLimit) {
                $sql .= " FETCH NEXT $limit ROWS ONLY";
            }

            return $sql;
        } else {
            return '';
        }
    }

//	public function resetSequence($table, $value = null)
//	{
//		return '';
//	}

    /**
     * Builds a SQL statement for renaming a DB table.
     * @param  string $table   the table to be renamed. The name will be properly quoted by the method.
     * @param  string $newName the new table name. The name will be properly quoted by the method.
     * @return string the SQL statement for renaming a DB table.
     */
    public function renameTable($table, $newName)
    {
        return "sp_rename '$table', '$newName'";
    }

    /**
     * Builds a SQL statement for renaming a column.
     * @param  string $table   the table whose column is to be renamed. The name will be properly quoted by the method.
     * @param  string $name    the old name of the column. The name will be properly quoted by the method.
     * @param  string $newName the new name of the column. The name will be properly quoted by the method.
     * @return string the SQL statement for renaming a DB column.
     */
    public function renameColumn($table, $name, $newName)
    {
        return "sp_rename '$table.$name', '$newName', 'COLUMN'";
    }

    /**
     * Builds a SQL statement for changing the definition of a column.
     * @param  string $table  the table whose column is to be changed. The table name will be properly quoted by the method.
     * @param  string $column the name of the column to be changed. The name will be properly quoted by the method.
     * @param  string $type   the new column type. The {@link getColumnType} method will be invoked to convert abstract column type (if any)
     *                        into the physical one. Anything that is not recognized as abstract type will be kept in the generated SQL.
     *                        For example, 'string' will be turned into 'varchar(255)', while 'string not null' will become 'varchar(255) not null'.
     * @return string the SQL statement for changing the definition of a column.
     */
    public function alterColumn($table, $column, $type)
    {
        $type = $this->getColumnType($type);
        $sql = 'ALTER TABLE ' . $this->db->quoteTableName($table) . ' ALTER COLUMN '
            . $this->db->quoteColumnName($column) . ' '
            . $this->getColumnType($type);

        return $sql;
    }

    /**
     * Builds a SQL statement for enabling or disabling integrity check.
     * @param  boolean               $check  whether to turn on or off the integrity check.
     * @param  string                $schema the schema of the tables. Defaults to empty string, meaning the current or default schema.
     * @param  string                $table  the table name. Defaults to empty string, meaning that no table will be changed.
     * @return string                the SQL statement for checking integrity
     * @throws InvalidParamException if the table does not exist or there is no sequence associated with the table.
     */
    public function checkIntegrity($check = true, $schema = '', $table = '')
    {
        if ($schema !== '') {
            $table = "{$schema}.{$table}";
        }
        $table = $this->db->quoteTableName($table);
        if ($this->db->getTableSchema($table) === null) {
            throw new InvalidParamException("Table not found: $table");
        }
        $enable = $check ? 'CHECK' : 'NOCHECK';

        return "ALTER TABLE {$table} {$enable} CONSTRAINT ALL";
    }
}
