<?php
// $Id$
/**
 * @file
 * Code For D6 to D7 field update.
 * 
 * Modules can implement hook_content_migrate_field_alter()
 * and hook_content_migrate_instance_alter()
 */
define('CONTENT_DB_STORAGE_PER_FIELD', 0);
define('CONTENT_DB_STORAGE_PER_CONTENT_TYPE', 1);

/**
 * Implements hook_menu().
 */
function content_migrate_menu() { 
  // Demo page.
  $items['admin/structure/content_migrate'] = array(
    'title' => 'Migrate fields',
    'description' => 'Migrate field settings and data from the Drupal 6 version to the Drupal 7 version.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('content_migrate_select'),
    'access arguments' => array('administer content types'),
    'file' => 'content_migrate.admin.inc',
  );

  return $items;
}

/**
 * Create a D7-style field array from data stored
 * in the D6 content field tables.
 *
 * @param $field_name 
 *   Optionally request only a specific field name.
 */
function content_migrate_get_field_values($field_name = NULL) {
  $field_values = &drupal_static(__FUNCTION__);
  if (!is_array($field_values)) {
    $field_values = array();
  }
  if (empty($field_values) && db_table_exists('content_node_field')) {
    $field_values = array();
    $query = db_select('content_node_field', 'nf', array('fetch' => PDO::FETCH_ASSOC));
    $node_instance_alias = $query->join('content_node_field_instance', 'ni', 'ni.field_name=nf.field_name');
    $result = $query
      ->fields($node_instance_alias, array('widget_type'))
      ->fields('nf')
      ->execute();
    
    foreach ($result as $row) {
      $field_value = $row;
    
      // All Drupal 6 fields were attached to nodes.
      $field_value['entity_types'] = array('node');
    
      $field_value['cardinality'] = $field_value['multiple'] != 1 ? $field_value['multiple'] : FIELD_CARDINALITY_UNLIMITED;
      
      // We need column information for the old table.
      $field_value['columns'] = unserialize($field_value['db_columns']);
    
      // Field settings.
      $default_settings = field_info_field_settings($row['type']);
      $field_value['settings'] = array_merge($default_settings, unserialize($field_value['global_settings']));
    
      unset($field_value['multiple'], $field_value['global_settings'], $field_value['required'], $field_value['db_columns']);
            
      // Let modules change these values.
      drupal_alter('content_migrate_field', $field_value);
      
      // We left the widget type in the $field_value so modules
      // could adjust the field based on that information.
      // Needed so optionwidgets can change the field type
      // from text or numeric to list. 
      unset($field_value['widget_type'], $field_value['allowed_values_php']);
      
      // We retain $field_value['columns'] and $field_value['db_storage']
      // even though they are not used or different in D7 
      // so we can find the old table information.
      
      // Add field definiation to $field_values array.
      $field_values[$field_value['field_name']] = $field_value;
    }
  }
  if (!empty($field_name)) {
    return $field_values[$field_name];
  }
  return $field_values;
}

/**
 * Create a D7-style instance array from data stored
 * in the D6 content field tables.
 *
 * @param $bundle
 *   Optionally request only instances of a specific bundle.
 * @param $field_name
 *   Optionally request only instances of a specific field_name.
 */
function content_migrate_get_instance_values($bundle = NULL, $field_name = NULL) {
  $instance_values = &drupal_static(__FUNCTION__);
  
  if (empty($instance_values) && db_table_exists('content_node_field_instance')) {
    $instance_values = array();
    $query = db_select('content_node_field_instance', 'ni', array('fetch' => PDO::FETCH_ASSOC));
    $node_field_alias = $query->join('content_node_field', 'nf', 'ni.field_name=nf.field_name');
    $result = $query
      ->fields('ni')
      ->fields($node_field_alias, array('required'))
      ->orderBy('label', 'ASC')
      ->execute();
    
    foreach ($result as $row) { 
      $instance_value = $row;
      
      // The instance has the same module as the field,
      // not the widget. May have been altered
      // from the original values, so get the altered
      // field values.
      $field_value = content_migrate_get_field_values($row['field_name']);
      $instance_value['module'] = $field_value['module'];
    
      // All Drupal 6 instances were attached to nodes.
      $instance_value['entity_type'] = 'node';
    
      // Unserialize arrays.
      foreach (array('widget_settings', 'display_settings', 'global_settings') as $key) {
        $instance_value[$key] = (!empty($instance_value[$key])) ? (array) unserialize($instance_value[$key]) : array();
      }
     
      // Build instance values.
      $instance_value['bundle'] = $instance_value['type_name'];
      $instance_value['active'] = $instance_value['widget_active'];
      $instance_value['default_value'] = $instance_value['widget_settings']['default_value'];
      
      // Core does not support this, but retain it so 
      // another module can do something with it
      // in drupal_alter.
      if (isset($instance_value['widget_settings']['default_value_php'])) {
        $instance_value['settings']['default_value_php'] = $instance_value['widget_settings']['default_value_php'];
      }

      // Build widget values.
      $instance_value['widget'] = array();
      
      // TODO Some widget types have been renamed in D7.
      $instance_value['widget']['type']     = $instance_value['widget_type'];
      $instance_value['widget']['weight']   = $instance_value['weight'];
      $instance_value['widget']['module']   = $instance_value['widget_module'];
    
      $default_settings = field_info_widget_settings($field_value['type']);
      $instance_value['widget']['settings'] = array_merge($default_settings, $instance_value['widget_settings']);
    
      // Build display values.
      $instance_value['display'] = $instance_value['display_settings'];
      $label = $instance_value['display_settings']['label'];
      foreach ($instance_value['display_settings'] as $context => $settings) {

        // @TODO Multigroup fields have some unexpected elements, we need to work out what should happen to them.
        if ($context == 'parent' || $context == 'weight') {
          continue;
        }
        $instance_value['display'][$context]['label'] = $label['format'];
        
        // The format used in D6 may not match the formatter in D7.
        // Fix it using drupal_alter().
        $instance_value['display'][$context]['type'] = $settings['format'];
        $instance_value['display'][$context]['settings'] = field_info_formatter_settings($settings['format']);

      }
      
      // Unset unneeded values.
      unset($instance_value['type_name'], $instance_value['global_settings'], $instance_value['widget_settings'], $instance_value['display_settings'], $instance_value['widget_module'], $instance_value['widget_active']);
      
      // Unset some values that don't exist on all fields.
      if (isset($instance_value['widget']['settings']['default_value'])) unset($instance_value['widget']['settings']['default_value']);
      if (isset($instance_value['widget']['settings']['default_value_php'])) unset($instance_value['widget']['settings']['default_value_php']);

      // Let modules change these values.
      drupal_alter('content_migrate_instance', $instance_value);
      
      // Get rid of this value once CCK or some other module has handled it.
      if (isset($instance_value['settings']['default_value_php'])) unset($instance_value['settings']['default_value_php']);

      // Add instance information to instance array.
      $instance_values['instances'][$instance_value['bundle']][$instance_value['field_name']] = $instance_value;
      $instance_values['fields'][$instance_value['field_name']][$instance_value['bundle']] = $instance_value;
      
    }
  }
  if (!empty($bundle)) {
    if (!empty($field_name)) {
      return $instance_values['instances'][$bundle][$field_name];
    }
    else {
      return $instance_values['instances'][$bundle];
    }
  }
  elseif (!empty($field_name)) {
    return $instance_values['fields'][$field_name];
  }
  return $instance_values;
}

/**
 * Helper function for finding the table name
 * used to store the D6 field data.
 *
 * @param $field_value
 * @param $instance_value
 */
function content_migrate_old_table($field_value, $instance_value) {
  $storage = content_migrate_storage_type($field_value);
  switch ($storage) {
    case CONTENT_DB_STORAGE_PER_CONTENT_TYPE :
      $name = $instance_value['bundle'];
      return "content_type_$name";
    case CONTENT_DB_STORAGE_PER_FIELD :
      $name = $field_value['field_name'];
      return "content_$name";
  }
}

/**
 * Helper function for finding the type of table
 * used for storing the D6 field data.
 *
 * @param $field_value
 * @param $instance_value
 */
function content_migrate_storage_type($field_value) {
  $storage = CONTENT_DB_STORAGE_PER_CONTENT_TYPE;
  if (isset($field_value['db_storage'])) {
    return $field_value['db_storage'];
  }
  elseif ($field_value['cardinality'] > 0 || $field_value['cardinality'] == FIELD_CARDINALITY_UNLIMITED) {
    $storage = CONTENT_DB_STORAGE_PER_FIELD;
  }
  else {
    $instance_values = content_migrate_get_instance_values(NULL, $field_value['field_name']);
    if (count($instance_values) > 1) {
      $storage = CONTENT_DB_STORAGE_PER_FIELD;
    }
  }
  return $storage;
}

/**
 * Helper function to find the table for a
 * D7 field array.
 *
 * @param $field
 */
function content_migrate_new_table($field) {
  if (empty($field['storage']['details'])) {
    return 'field_data_'. $field['field_name'];
  }
  $data = $field['storage']['details']['sql'][FIELD_LOAD_CURRENT];
  return key($data);
}

function content_migrate_new_revision($field) {
  if (empty($field['storage']['details'])) {
    return 'field_revision_'. $field['field_name'];
  }
  $data = $field['storage']['details']['sql'][FIELD_LOAD_REVISION];
  return key($data);
}

/**
 * Helper function for finding the column names
 * used for storing the D6 field data.
 *
 * @param $field_value
 * @param $instance_value
 */
function content_migrate_old_columns($field_value, $instance_value) {
  $columns = array();
  foreach ($field_value['columns'] as $col => $values) {
    $columns[] = $field_value['field_name'] .'_'. $col;
  }
  return $columns;
}
/**
 * Helper function for figuring out column names
 * to be used when storing D7 field data.
 *
 * @param unknown_type $field
 * @return unknown
 */
function content_migrate_new_columns($field) {
  $columns = array();
  if (empty($field['storage']['details'])) {
    foreach ($field['columns'] as $col => $values) {
      $columns[] = $field['field_name'] .'_'. $col;
    }
    return $columns;
  }
  else {
    foreach ($field['storage']['details']['sql'][FIELD_LOAD_CURRENT] as $table => $cols) {
      foreach ($cols as $col) {
        $columns[] = $col;
      }
    }
    return $columns;
  }
}

/**
 * Implements hook_content_migrate_field_alter().
 * 
 * Use this to tweak the conversion of field settings
 * from the D6 style to the D7 style for specific
 * situations not handled by basic conversion,
 * as when field types or settings are changed.
 * 
 * $field_value['widget_type'] is available to
 * see what widget type was originally used.
 */
function content_migrate_content_migrate_field_alter(&$field_value) {
  
  switch ($field_value['type']) {
    case 'text':
      
      // The max_length field can no longer be empty 
      // or it will create a SQL error.
      if (empty($field_value['settings']['max_length'])) {
        $field_value['settings']['max_length'] = 255;
      }
      
      // Text fields using optionwidgets are
      // now List fields.
      switch ($field_value['widget_type']) {
        case 'optionwidgets_buttons':
        case 'optionwidgets_select':
          $field_value['type'] = 'list_text';
          $field_value['module'] = 'list';
          break;
        case 'optionwidgets_onoff':
          $field_value['type'] = 'list_boolean';
          $field_value['module'] = 'list';
          break;  
        case 'text_textarea':
          $field_value['type'] = 'text_long';
          unset($field_value['settings']['max_length']);
          break;  
      }
      break;
   
    case 'number_integer':
    case 'number_decimal':
    case 'number_float':  
      
      // Changed name of setting from 'decimal' to 
      // 'decimal_separator'.
      if (isset($field_value['settings']['decimal'])) {
        $field_value['settings']['decimal_separator'] = $field_value['settings']['decimal'];
        unset($field_value['settings']['decimal']);
      }
      // Add a decimal_separator setting to floats.
      if ($field_value['type'] == 'number_float') {
        $field_value['settings']['decimal_separator'] = '.';
      }
      
      // Number fields using optionwidgets are
      // now List fields.
      switch ($field_value['widget_type']) {
        case 'optionwidgets_buttons':
        case 'optionwidgets_select':
          $field_value['type'] = 'list_number';
          $field_value['module'] = 'list';
          break;
        case 'optionwidgets_onoff':
          $field_value['type'] = 'list_boolean';
          $field_value['module'] = 'list';
          break;  
      }
      break;  
  }
}

/**
 * Implements hook_content_migrate_instance_alter().
 * 
 * Use this to tweak the conversion of instance or widget settings
 * from the D6 style to the D7 style for specific
 * situations not handled by basic conversion, as when
 * formatter or widget names or settings are changed.
 */
function content_migrate_content_migrate_instance_alter(&$instance_value) {
  //$field = content_migrate_get_field_values($instance_value['field_name']);
  
  switch ($instance_value['widget']['module']) {
    // Optionswidgets module became Options module
    // and widget type names changed.
    case ('optionwidgets'):
      $replace = array(
        'optionwidgets_select' => 'options_select',
        'optionwidgets_buttons' => 'options_buttons',
        'optionwidgets_onoff' => 'options_onoff',
      );
      $instance_value['widget']['module'] = 'options';
      $instance_value['widget']['type'] = strtr($instance_value['widget']['type'], $replace);
      break;
  }
  
  switch ($instance_value['module']) {
    case 'text':
      // The formatter names changed, all are prefixed
      // with 'text_'.
      foreach ($instance_value['display'] as $context => $settings) {
        $instance_value['display'][$context]['type'] = 'text_'. $settings['type'];
      }     
      break;
      
    case 'number':    
      // The number formatters and formatter settings
      // have changed.
      $new_type = array(
        'unformatted' => 'number_unformatted',
        'default' => 'number_decimal',
        'us_0' => 'number_integer',
        'us_1' => 'number_decimal',
        'us_2' => 'number_decimal',
        'be_0' => 'number_integer',
        'be_1' => 'number_decimal',
        'be_2' => 'number_decimal',        
        'fr_0' => 'number_integer',
        'fr_1' => 'number_decimal',
        'fr_2' => 'number_decimal',      
      );
      $new_settings = array(
        'default' => array(
          'thousand_separator' => '',
          'decimal_separator' => '.',
          'scale' => 0,
          'prefix_suffix' => TRUE,
        ),
        'us_0' => array(
          'thousand_separator' => ',',
          'decimal_separator' => '.',
          'scale' => 0,
          'prefix_suffix' => TRUE,
        ),        
        'us_1' => array(
          'thousand_separator' => ',',
          'decimal_separator' => '.',
          'scale' => 1,
          'prefix_suffix' => TRUE,
        ),
        'us_2' => array(
          'thousand_separator' => ',',
          'decimal_separator' => '.',
          'scale' => 2,
          'prefix_suffix' => TRUE,
        ),  
        'be_0' => array(
          'thousand_separator' => '',
          'decimal_separator' => ',',
          'scale' => 0,
          'prefix_suffix' => TRUE,
        ),        
        'be_1' => array(
          'thousand_separator' => '.',
          'decimal_separator' => ',',
          'scale' => 1,
          'prefix_suffix' => TRUE,
        ),
        'be_2' => array(
          'thousand_separator' => '.',
          'decimal_separator' => ',',
          'scale' => 2,
          'prefix_suffix' => TRUE,
        ),         
        'fr_0' => array(
          'thousand_separator' => '',
          'decimal_separator' => ', ',
          'scale' => 0,
          'prefix_suffix' => TRUE,
        ),        
        'fr_1' => array(
          'thousand_separator' => ' ',
          'decimal_separator' => ', ',
          'scale' => 1,
          'prefix_suffix' => TRUE,
        ),
        'fr_2' => array(
          'thousand_separator' => ' ',
          'decimal_separator' => ', ',
          'scale' => 2,
          'prefix_suffix' => TRUE,
        ),                          
      );
      foreach ($instance_value['display'] as $context => $settings) {
        $instance_value['display'][$context]['type'] = $new_type[$settings['type']];
        $instance_value['display'][$context]['settings'] = $new_settings[$settings['type']];
      }
      break;
  }
}