<?php
/*
 +--------------------------------------------------------------------+
 | Copyright CiviCRM LLC. All rights reserved.                        |
 |                                                                    |
 | This work is published under the GNU AGPLv3 license with some      |
 | permitted exceptions and without any warranty. For full license    |
 | and copyright information, see https://civicrm.org/licensing       |
 +--------------------------------------------------------------------+
 */

/**
 * This class exists primarily for the purposes of supporting code clean up in the Merger class.
 *
 * It is expected to be fast-moving and calling it outside the refactoring work is not advised.
 *
 * @package CRM
 * @copyright CiviCRM LLC https://civicrm.org/licensing
 */
class CRM_Dedupe_MergeHandler {

  /**
   * ID of contact to be kept.
   *
   * @var int
   */
  protected $toKeepID;

  /**
   * ID of contact to be merged and deleted.
   *
   * @var int
   */
  protected $toRemoveID;

  /**
   * Migration info array.
   *
   * This is a nasty bunch of data used in mysterious ways. We want to work to make it more
   * sensible but for now we store it.
   *
   * @var array
   */
  protected $migrationInfo = [];

  /**
   * @return array
   */
  public function getMigrationInfo(): array {
    return $this->migrationInfo;
  }

  /**
   * @param array $migrationInfo
   */
  public function setMigrationInfo(array $migrationInfo) {
    $this->migrationInfo = $migrationInfo;
  }

  /**
   * @return mixed
   */
  public function getToKeepID() {
    return $this->toKeepID;
  }

  /**
   * @param mixed $toKeepID
   */
  public function setToKeepID($toKeepID) {
    $this->toKeepID = $toKeepID;
  }

  /**
   * @return mixed
   */
  public function getToRemoveID() {
    return $this->toRemoveID;
  }

  /**
   * @param mixed $toRemoveID
   */
  public function setToRemoveID($toRemoveID) {
    $this->toRemoveID = $toRemoveID;
  }

  /**
   * CRM_Dedupe_MergeHandler constructor.
   *
   * @param int $toKeepID
   *   ID of contact to be kept.
   * @param int $toRemoveID
   *   ID of contact to be removed.
   */
  public function __construct(int $toKeepID, int $toRemoveID) {
    $this->setToKeepID($toKeepID);
    $this->setToRemoveID($toRemoveID);
  }

  /**
   * Get an array of tables that relate to the contact entity and will need consideration in a merge.
   *
   * The list of potential tables is filtered by tables which have data for the relevant contacts.
   */
  public function getTablesRelatedToTheMergePair() {
    $relTables = CRM_Dedupe_Merger::relTables();
    $activeRelTables = CRM_Dedupe_Merger::getActiveRelTables($this->toRemoveID);
    $activeMainRelTables = CRM_Dedupe_Merger::getActiveRelTables($this->toKeepID);
    foreach ($relTables as $name => $null) {
      if (!in_array($name, $activeRelTables, TRUE) &&
        !(($name === 'rel_table_users') && in_array($name, $activeMainRelTables, TRUE))
      ) {
        unset($relTables[$name]);
      }
    }
    return $relTables;
  }

  /**
   * Get an array of tables that have a dynamic reference to the contact table.
   *
   * This would be the case when the table uses entity_table + entity_id rather than an FK.
   *
   * There are a number of tables that 'could' but don't have contact related data so we
   * do a cached check for this, ensuring the query is only done once per batch run.
   *
   * @return array
   */
  public function getTablesDynamicallyRelatedToContactTable() {
    if (!isset(\Civi::$statics[__CLASS__]['dynamic'])) {
      \Civi::$statics[__CLASS__]['dynamic'] = [];
      foreach (CRM_Core_DAO::getDynamicReferencesToTable('civicrm_contact') as $tableName => $fields) {
        if ($tableName === 'civicrm_financial_item') {
          // It turns out that civicrm_financial_item does not have an index on entity_table (only as the latter
          // part of a entity_id/entity_table index which probably is not adding any value over & above entity_id
          // only. This means this is a slow query. The correct fix is probably to add a whitelist to
          // values for entity_table in the schema.
          continue;
        }
        foreach ($fields as $field) {
          $sql[] = "(SELECT '$tableName' as civicrm_table, '{$field[0]}' as field_name FROM $tableName WHERE {$field[1]} = 'civicrm_contact' LIMIT 1)";
        }
      }
      $sqlString = implode(' UNION ', $sql);
      if ($sqlString) {
        $result = CRM_Core_DAO::executeQuery($sqlString);
        while ($result->fetch()) {
          \Civi::$statics[__CLASS__]['dynamic'][$result->civicrm_table] = $result->field_name;
        }
      }
    }
    return \Civi::$statics[__CLASS__]['dynamic'];
  }

  /**
   * Get the location blocks designated to be moved during the merge.
   *
   * Note this is a refactoring step and future refactors should develop a more coherent array
   *
   * @return array
   *   The format is ['address' => [0 => ['is_replace' => TRUE]], 'email' => [0...],[1....]
   *   where the entity is address, the internal indexing for the addresses on both contact is 1
   *   and the intent to replace the existing address is TRUE.
   */
  public function getLocationBlocksToMerge(): array {
    $locBlocks = [];
    foreach ($this->getMigrationInfo() as $key => $value) {
      $isLocationField = (substr($key, 0, 14) === 'move_location_' and $value != NULL);
      if (!$isLocationField) {
        continue;
      }
      $locField = explode('_', $key);
      $fieldName = $locField[2];
      $fieldCount = $locField[3];

      // Set up the operation type (add/overwrite)
      // Ignore operation for websites
      // @todo Tidy this up
      $operation = 0;
      if ($fieldName !== 'website') {
        $operation = $this->getMigrationInfo()['location_blocks'][$fieldName][$fieldCount]['operation'] ?? NULL;
      }
      // default operation is overwrite.
      if (!$operation) {
        $operation = 2;
      }
      $locBlocks[$fieldName][$fieldCount]['is_replace'] = $operation === 2;
    }
    return $locBlocks;
  }

  /**
   * Copy the data to be moved to a new DAO object.
   *
   * This is intended as a refactoring step - not the long term function. Do not
   * call from any function other than the one it is taken from (Merger::mergeLocations).
   *
   * @param int $otherBlockId
   * @param string $name
   * @param int $blkCount
   *
   * @return CRM_Core_DAO_Address|CRM_Core_DAO_Email|CRM_Core_DAO_IM|CRM_Core_DAO_Phone|CRM_Core_DAO_Website
   *
   * @throws \CRM_Core_Exception
   */
  public function copyDataToNewBlockDAO($otherBlockId, $name, $blkCount) {
    // For the block which belongs to other-contact, link the location block to main-contact
    $otherBlockDAO = $this->getDAOForLocationEntity($name, $this->getSelectedLocationType($name, $blkCount), $this->getSelectedType($name, $blkCount));
    $otherBlockDAO->contact_id = $this->getToKeepID();
    // Get the ID of this block on the 'other' contact, otherwise skip
    $otherBlockDAO->id = $otherBlockId;
    return $otherBlockDAO;
  }

  /**
   * Get blocks, if any, to update for the deleted contact.
   *
   * If the deleted contact no longer has a primary address but still has
   * one or more blocks we want to ensure the remaining block is updated
   * to have is_primary = 1 in case the contact is ever undeleted.
   *
   * @param string $entity
   *
   * @return array
   * @throws \CRM_Core_Exception
   */
  public function getBlocksToUpdateForDeletedContact($entity) {
    $movedBlocks = $this->getLocationBlocksToMerge()[$entity];
    $deletedContactsBlocks = $this->getLocationBlocksForContactToRemove()[$entity];
    $unMovedBlocks = array_values(array_diff_key($deletedContactsBlocks, $movedBlocks));
    if (empty($unMovedBlocks) || empty($movedBlocks)) {
      return [];
    }
    foreach (array_keys($movedBlocks) as $index) {
      if ($deletedContactsBlocks[$index]['is_primary']) {
        // We have moved the primary - change any other block to be primary.
        $newPrimaryBlock = $this->getDAOForLocationEntity($entity);
        $newPrimaryBlock->id = $unMovedBlocks[0]['id'];
        $newPrimaryBlock->is_primary = 1;
        return [$newPrimaryBlock->id => $newPrimaryBlock];
      }
    }
    return [];
  }

  /**
   * Get the details of the blocks to be transferred over for the given entity.
   *
   * @param string $entity
   *
   * @return array
   */
  protected function getLocationBlocksToMoveForEntity($entity) {
    $movedBlocks = $this->getLocationBlocksToMerge()[$entity];
    $blockDetails = $this->getLocationBlocksForContactToRemove()[$entity];
    return array_intersect_key($blockDetails, $movedBlocks);
  }

  /**
   * Does the contact to keep have location blocks for the given entity.
   *
   * @param string $entity
   *
   * @return bool
   */
  public function contactToKeepHasLocationBlocksForEntity($entity) {
    return !empty($this->getLocationBlocksForContactToKeep()[$entity]);
  }

  /**
   * Get the location blocks for the contact to be kept.
   *
   * @return array
   */
  public function getLocationBlocksForContactToKeep() {
    return $this->getMigrationInfo()['main_details']['location_blocks'];
  }

  /**
   * Get the location blocks for the contact to be deleted.
   *
   * @return array
   */
  public function getLocationBlocksForContactToRemove() {
    return $this->getMigrationInfo()['other_details']['location_blocks'];
  }

  /**
   * Get the DAO object appropriate to the location entity.
   *
   * @param string $entity
   *
   * @param int|null $locationTypeID
   * @param int|null $typeID
   *
   * @return CRM_Core_DAO_Address|CRM_Core_DAO_Email|CRM_Core_DAO_IM|CRM_Core_DAO_Phone|CRM_Core_DAO_Website
   * @throws \CRM_Core_Exception
   */
  public function getDAOForLocationEntity($entity, $locationTypeID = NULL, $typeID = NULL) {
    switch ($entity) {
      case 'email':
        $dao = new CRM_Core_DAO_Email();
        $dao->location_type_id = $locationTypeID;
        return $dao;

      case 'address':
        $dao = new CRM_Core_DAO_Address();
        $dao->location_type_id = $locationTypeID;
        return $dao;

      case 'phone':
        $dao = new CRM_Core_DAO_Phone();
        $dao->location_type_id = $locationTypeID;
        $dao->phone_type_id = $typeID;
        return $dao;

      case 'website':
        $dao = new CRM_Core_DAO_Website();
        $dao->website_type_id = $typeID;
        return $dao;

      case 'im':
        $dao = new CRM_Core_DAO_IM();
        $dao->location_type_id = $locationTypeID;
        return $dao;

      default:
        // Mostly here, along with the switch over a more concise format, to help IDEs understand the possibilities.
        throw new CRM_Core_Exception('Unsupported entity');
    }
  }

  /**
   * Get the selected location type for the given location block.
   *
   * This will retrieve any user selection if they specified which location to move a block to.
   *
   * @param string $entity
   * @param int $blockIndex
   *
   * @return int|null
   */
  protected function getSelectedLocationType($entity, $blockIndex) {
    return $this->getMigrationInfo()['location_blocks'][$entity][$blockIndex]['locTypeId'] ?? NULL;
  }

  /**
   * Get the selected type for the given location block.
   *
   * This will retrieve any user selection if they specified which type to move a block to (e.g 'Mobile' for phone).
   *
   * @param string $entity
   * @param int $blockIndex
   *
   * @return int|null
   */
  protected function getSelectedType($entity, $blockIndex) {
    return $this->getMigrationInfo()['location_blocks'][$entity][$blockIndex]['typeTypeId'] ?? NULL;
  }

}