<?php

/**
 * Implementation of hook_schema().
 */
function image_attach_schema() {
  $schema['image_attach'] = array(
    'description' => 'Stores the image/node relationship.',
    'fields' => array(
      'nid' => array(
        'description' => 'The {node}.nid of the node.',
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 0,
      ),
      'iid' => array(
        'description' => 'The {image}.nid of the image file.',
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 0,
      ),
      'weight' => array(
        'description' => 'The display order of attached images.',
        'type' => 'int',
        'not null' => TRUE,
        'default' => 0,
      ),
    ),
    'primary key' => array('nid', 'iid'),
    'indexes' => array(
      'iid' => array('iid'),
    ),
  );
  return $schema;
}

/**
 * Implementation of hook_install().
 */
function image_attach_install() {
  drupal_install_schema('image_attach');
}

/**
 * Implementation of hook_uninstall().
 */
function image_attach_uninstall() {
  drupal_uninstall_schema('image_attach');
  variable_del('image_attach_existing');
  variable_del('image_attach_block_0_size');
}

/**
 * Add an index to the image id field.
 */
function image_attach_update_1() {
  $ret = array();
  switch ($GLOBALS['db_type']) {
    case 'mysql':
    case 'mysqli':
      $ret[] = update_sql("ALTER TABLE {image_attach} ADD KEY (iid)");
      break;

    case 'pgsql':
      $ret[] = update_sql("CREATE INDEX {image_attach}_iid_idx ON {image_attach}(iid)");
      break;
  }
  return $ret;
}

/**
 * Remove attach records that point to a missing image.
 */
function image_attach_update_2() {
  $ret = array();
  switch ($GLOBALS['db_type']) {
    case 'mysqli':
    case 'mysql':
      $ret[] = update_sql("DELETE FROM {image_attach} USING {image_attach} LEFT JOIN {node} n ON {image_attach}.iid = n.nid WHERE n.nid IS NULL OR n.type <> 'image'");
      break;

    case 'pgsql':
      $ret[] = update_sql("DELETE FROM {image_attach} USING {node} n WHERE {image_attach}.iid = n.nid AND (n.nid IS NULL OR n.type <> 'image')");
      break;
  }
  return $ret;
}

/**
 * Add primary key and index on 'iid' to {image_attach} table.
 */
function image_attach_update_6100() {
  $ret = array();
  db_change_field($ret, 'image_attach', 'nid', 'nid', array(
    'type' => 'int',
    'unsigned' => TRUE,
    'not null' => TRUE,
    'default' => 0,
  ));
  db_change_field($ret, 'image_attach', 'iid', 'iid', array(
    'type' => 'int',
    'unsigned' => TRUE,
    'not null' => TRUE,
    'default' => 0,
  ));

  /**
   * We remove and re-add primary keys and indexes because the column types
   * are changed.
   * Sometimes however these don't exist in the first place (@see
   * <http://drupal.org/node/562810>; the @ takes care of suppressing the
   * error message this causes.
   */
  @db_drop_primary_key($ret, 'image_attach');
  db_add_primary_key($ret, 'image_attach', array('nid'));
  @db_drop_index($ret, 'image_attach', 'iid');
  db_add_index($ret, 'image_attach', 'iid', array('iid'));

  // Notify the user that they may get harmless fail messages here.
  $ret[] = array('success' => TRUE, 'query' => t('If you see a message of the form "Failed: ALTER TABLE {image_attach} DROP PRIMARY KEY" or "DROP INDEX iid" here it is harmless.'));
  return $ret;
}

/**
 * Delete bad entry in {blocks} table due to old bug.
 * Next visit to blocks admin page will rehash and show the block.
 * @see <http://drupal.org/node/426724>
 */
function image_attach_update_6101() {
  $ret = array();
  $ret[] = update_sql("DELETE FROM {blocks} WHERE module = 'image_attach' AND delta = '0'");

  return $ret;
}

/**
 * Adjust primary key on {image_attach} to allow multiple attachments.
 */
function image_attach_update_6102() {
  $ret = array();
  db_drop_primary_key($ret, 'image_attach');
  db_add_primary_key($ret, 'image_attach', array('nid', 'iid'));
  db_add_field($ret, 'image_attach', 'weight', array(
    'type' => 'int',
    'not null' => TRUE,
    'default' => 0,
  ));
  return $ret;
}

/**
 * Remove erroneous data inside image_attach table, where iid = 0.
 */
function image_attach_update_6103() {
  $ret = array();
  $ret[] = update_sql("DELETE FROM {image_attach} WHERE iid = 0");
  return $ret;
}