<?php
// $Id$

/**
 * @file
 * Tests for the Database Schema API.
 */

/**
 * Unit tests for the Schema API.
 */
class SchemaTestCase extends DrupalWebTestCase {
  public static function getInfo() {
    return array(
      'name' => t('Schema API'),
      'description' => t('Tests table creation and modification via the schema API.'),
      'group' => t('Database'),
    );
  }

  /**
   *
   */
  function testSchema() {
    // Try creating a table.
    $table_specification = array(
      'description' => 'Schema table description.',
      'fields' => array(
        'id'  => array(
          'type' => 'int',
          'default' => NULL,
        ),
        'test_field'  => array(
          'type' => 'int',
          'not null' => TRUE,
          'description' => 'Schema column description.',
        ),
      ),
    );
    $ret = array();
    db_create_table($ret, 'test_table', $table_specification);

    // Assert that the table exists.
    $this->assertTrue(db_table_exists('test_table'), t('The table exists.'));

    // Assert that the table comment has been set.
    $this->checkSchemaComment($table_specification['description'], 'test_table');

    // Assert that the column comment has been set.
    $this->checkSchemaComment($table_specification['fields']['test_field']['description'], 'test_table', 'test_field');

    // An insert without a value for the column 'test_table' should fail.
    $this->assertFalse($this->tryInsert(), t('Insert without a default failed.'));

    // Add a default value to the column.
    db_field_set_default($ret, 'test_table', 'test_field', 0);
    // The insert should now succeed.
    $this->assertTrue($this->tryInsert(), t('Insert with a default succeeded.'));

    // Remove the default.
    db_field_set_no_default($ret, 'test_table', 'test_field');
    // The insert should fail again.
    $this->assertFalse($this->tryInsert(), t('Insert without a default failed.'));

    // Rename the table.
    db_rename_table($ret, 'test_table', 'test_table2');
    // We need the default so that we can insert after the rename.
    db_field_set_default($ret, 'test_table2', 'test_field', 0);
    $this->assertFalse($this->tryInsert(), t('Insert into the old table failed.'));
    $this->assertTrue($this->tryInsert('test_table2'), t('Insert into the new table succeeded.'));

    // We should have successfully inserted exactly two rows.
    $count = db_query('SELECT COUNT(*) FROM {test_table2}')->fetchField();
    $this->assertEqual($count, 2, t('Two fields were successfully inserted.'));

    // Try to drop the table.
    db_drop_table($ret, 'test_table2');
    $this->assertFalse(db_table_exists('test_table2'), t('The dropped table does not exist.'));

    // Recreate the table.
    db_create_table($ret, 'test_table', $table_specification);
    db_field_set_default($ret, 'test_table', 'test_field', 0);
    db_add_field($ret, 'test_table', 'test_serial', array('type' => 'int', 'not null' => TRUE, 'default' => 0, 'description' => 'Added column description.'));

    // Assert that the column comment has been set.
    $this->checkSchemaComment('Added column description.', 'test_table', 'test_serial');

    // Change the new field to a serial column.
    db_change_field($ret, 'test_table', 'test_serial', 'test_serial', array('type' => 'serial', 'not null' => TRUE, 'description' => 'Changed column description.'), array('primary key' => array('test_serial')));

    // Assert that the column comment has been set.
    $this->checkSchemaComment('Changed column description.', 'test_table', 'test_serial');

    $this->assertTrue($this->tryInsert(), t('Insert with a serial succeeded.'));
    $max1 = db_query('SELECT MAX(test_serial) FROM {test_table}')->fetchField();
    $this->assertTrue($this->tryInsert(), t('Insert with a serial succeeded.'));
    $max2 = db_query('SELECT MAX(test_serial) FROM {test_table}')->fetchField();
    $this->assertTrue($max2 > $max1, t('The serial is monotone.'));

    $count = db_query('SELECT COUNT(*) FROM {test_table}')->fetchField();
    $this->assertEqual($count, 2, t('There were two rows.'));
  }

  function tryInsert($table = 'test_table') {
    try {
      db_query("INSERT INTO {" . $table . "} (id) VALUES (:id)", array(':id' => mt_rand(10,20)));
      return TRUE;
    }
    catch (Exception $e) {
      return FALSE;
    }
  }

  /**
   * Checks that a table or column comment matches a given description.
   *
   * @param $description
   *   The asserted description.
   * @param $table
   *   The table to test.
   * @param $column
   *   Optional column to test.
   */
  function checkSchemaComment($description, $table, $column = NULL) {
    if (method_exists(Database::getConnection()->schema(), 'getComment')) {
      $comment = Database::getConnection()->schema()->getComment($table, $column);
      $this->assertEqual($comment, $description, t('The comment matches the schema description.'));
    }
  }
}