<?php
/**
 * Class for CiviRules Advanced Update Date Action Form
 *
 * @author David Hayes (Black Brick Software) <david@blackbrick.software>
 * @license AGPL-3.0
 */

use CRM_Civirules_ExtensionUtil as E;

class CRM_CivirulesActions_Generic_UpdateDateValue extends CRM_Civirules_Action {

  /**
   * Method processAction to execute the action
   *
   * @param CRM_Civirules_TriggerData_TriggerData $triggerData
   * @access public
   */
  public function processAction(CRM_Civirules_TriggerData_TriggerData $triggerData) {
    
    $contact_id = $triggerData->getContactId();
    $action_params = $this->getActionParameters();
    if (empty($action_params))
      return;

    // $entity_id = $triggerData->getEntityId(); // for what ever reason this is sometime empty
    // $trigger = $triggerData->getTrigger();
    // $ojbectName = null;
    // if ($trigger instanceof CRM_Civirules_Trigger_Post)
    //   $ojbectName = $trigger->getObjectName();  

    // parse target field parts
    try {
      list($target_entity, $target_field_id) = $this->parseRawFieldId($action_params['target_field_id']);
    } catch(Exception $e) {
      Civi::log()->debug('UpdateDateCustomValue Action: Error parsing target field name ('.$e->getMessage().')');
      return;
    }

    // get current value
    try {
      $old_value = $this->getValue($target_entity, $target_field_id, $contact_id, 'value');
    } catch(Exception $e) {
      Civi::log()->debug('UpdateDateCustomValue Action: Error retrieving target entity value ('.$e->getMessage().')');
      return;
    }
    $new_value = $old_value;

    // calculate new value
    if ($action_params['update_operation']==='set') {

      // proecess to datetime
      try {
        $new_value_datetime = new DateTime($action_params['update_operand']);
        $new_value = $new_value_datetime->format('Y-m-d H:i:s');
      } catch (Exception $e) {
        Civi::log()->debug("UpdateDateCustomValue Action: Unknown DateTime::__construct operand '{$action_params['update_operand']}'.");
        return;
      }

    } else {

      // parse target field parts
      try {
        list($source_entity, $source_field_id) = $this->parseRawFieldId($action_params['source_field_id']);
      } catch(Exception $e) {
        Civi::log()->debug('UpdateDateCustomValue Action: Error parsing source field name ('.$e->getMessage().')');
        return;
      }
      if (in_array(strtolower($source_entity), ['contact', 'individual', 'organization', 'household'])) {
        // source is a contact field
        $source_entity_id = $contact_id;
      } else {
        // source is the triggering entity
        $source_entity_data = $triggerData->getEntityData($source_entity);
        if (empty($source_entity_data)) {
          Civi::log()->debug("UpdateDateCustomValue Action: Source Entity Data or ID is empty for '{$source_entity}'");
          return;
        }
        if (empty($source_entity_data['id'])) {
          Civi::log()->debug("UpdateDateCustomValue Action: Source Entity ID is empty '{$source_entity_data['id']}'");
          return;
        }
        $source_entity_id = $source_entity_data['id'];
      }

      try {
        switch ($action_params['update_operation']) {
          case 'modify':
            $new_value = $this->getValue($source_entity, $source_field_id, $source_entity_id, 'value');
            break;
          case 'max_modify':
            $new_value = $this->getValue($source_entity, $source_field_id, $source_entity_id, 'max');
            break;
          case 'min_modify':
            $new_value = $this->getValue($source_entity, $source_field_id, $source_entity_id, 'min');
            break;
          default:
            Civi::log()->debug("UpdateDateCustomValue Action: Unknown operation '{$action_params['update_operation']}'.");
            return;
        }
      } catch (Exception $e) {
        Civi::log()->debug("$source_entity, $source_field_id, $source_entity_id, 'value'");
        Civi::log()->debug('UpdateDateCustomValue Action: Error retrieving source entity value ('.$e->getMessage().')');
        return;
      }
      
      // proecess to datetime
      if (!empty($action_params['update_operand'])) {
        try {
          $new_value_datetime = new DateTime($new_value);
          $new_value_datetime->modify($action_params['update_operand']);
          $new_value = $new_value_datetime->format('Y-m-d H:i:s');
        } catch (Exception $e) {
          Civi::log()->debug("UpdateDateCustomValue Action: Unknown DateTime::__construct or DateTime::modify format for source field '{$action_params['target_field_id']}' or operand '{$action_params['update_operand']}'.");
          return;
        }
      }

    }

    if ($old_value != $new_value) {
      try {
        $this->setValue($target_entity, $target_field_id, $contact_id, $new_value);
      } catch(Exception $e) {
        Civi::log()->debug('UpdateDateCustomValue Action: Error setting target entity value ('.$e->getMessage().')');
        return;
      }
    }
  }

  /**
   * Parse saved field id into entity type and field id (eg Contact:10 to Contact and 10)
   * 
   * @param string $raw_field_id
   * @return array [entity_type, field_id]
   * @throws Exception when field id is invalid
   */
  protected function parseRawFieldId($raw_field_id) {

    $field_parts = explode('::', $raw_field_id);
    
    if (count($field_parts)!==2)
      throw new Exception("Invalid field format '{$raw_field_id}'.");

    list($entity_type, $field_id) = $field_parts;

    $entity_search = civicrm_api3('Entity', 'get', [
      'sequential' => 1,
    ]);

    $entities = array_map('strtolower', $entity_search['values']);
    if (!in_array(strtolower($entity_type), $entities))
      throw new Exception("Invalid entity for field '{$raw_field_id}'.");

    return $field_parts;
  }

  /**
   * Set the value to the given field
   * 
   * @param string $entity_type entity type of primary object trigger; Only Contact is supported
   * @param int $entity_id      entity ID of primary object trigger
   * @param string $field_id    field ID or special fields like 'contact_id'
   * @param string $new_value   new value to set
   * @return void
   * @throws Exception when unable to set value
   */
  protected function setValue($entity_type, $field_id, $entity_id, $new_value) {
    if (strtolower($entity_type)==='contact') {
      if (is_numeric($field_id)) {
        civicrm_api3('Contact', 'create', [
          'id'                 => $entity_id,
          "custom_{$field_id}" => $new_value,
        ]);
      } else {
        // this shouldn't happen
        throw new Exception("Unknown field id '{$field_id}'.");
      }
    } else {
      throw new Exception("Unsupported update entity '{$entity_type}'.");
    }
  }


  /**
   * Get the value of the given field for the given contact
   *
   * @param string $entity_type entity type of primary object trigger
   * @param int $entity_id      entity ID of primary object trigger
   * @param string $field_id    field ID or special fields like 'contact_id'
   * @param string $mode        string can be 'value', 'min' or 'max'
   * @return mixed              current value
   * @throws Exception when unable to retrieve value
   */
  protected function getValue($entity_type, $field_id, $entity_id, $mode) {

    if ($mode == 'value') {
      if (is_numeric($field_id)) {
        return civicrm_api3($entity_type, 'getvalue', [
          'id' => $entity_id,
          'return' => "custom_{$field_id}",
        ]);
      } elseif (!empty($field_id)) {
        return civicrm_api3($entity_type, 'getvalue', [
          'id' => $entity_id,
          'return' => $field_id,
        ]);
      } else {
        throw new Exception("Unknown field id '{$field_id}'.");
      }
    }

    // MIN / MAX mode
    if ($mode==='min' || $mode==='max') {
      if (in_array(strtolower($entity_type), ['contact', 'individual', 'organization', 'household'])) {
        if (is_numeric($field_id)) {
          $custom_field = civicrm_api3('CustomField', 'getsingle', [
            'id'     => $field_id,
            'return' => 'custom_group_id,column_name',
          ]);
          $custom_group = civicrm_api3('CustomGroup', 'getsingle', [
            'id'     => $custom_field['custom_group_id'],
            'return' => 'table_name',
          ]);
          return CRM_Core_DAO::singleValueQuery("
            SELECT {$mode}({$custom_field['column_name']}) 
            FROM {$custom_group['table_name']}
            LEFT JOIN civicrm_contact contact
              ON contact.id = {$custom_group['table_name']}.entity_id  
            WHERE (contact.is_deleted IS NULL OR contact.is_deleted = 0);
          ");
        } else {
          // this should not happen
          throw new Exception("Unknown field id '{$field_id}'.");
        }
      } else {
        throw new Exception("Unsupported mode '{$mode}' for entity '{$entity_type}' and field '{$field_id}'.");
      }
    }

    // this should not happen
    throw new Exception("Unknown mode '{$mode}'.");
  }

  /**
   * Method to return the url for additional form processing for action
   * and return false if none is needed
   *
   * @param int $ruleActionId
   * @return bool
   * @access public
   */
  public function getExtraDataInputUrl($ruleActionId) {
    return CRM_Utils_System::url('civicrm/civirule/form/action/generic/updatedatevalue', 'rule_action_id='.$ruleActionId);
  }

  /**
   * Returns a user friendly text explaining the condition params
   * e.g. 'Older than 65'
   *
   * @return string
   * @access public
   * @throws \CiviCRM_API3_Exception
   */
  public function userFriendlyConditionParams() {
    
    $action_params = $this->getActionParameters();

    try {
      list($target_entity, $target_field_id) = $this->parseRawFieldId($action_params['target_field_id']);
      $target_field = '"' . $this->getHumanReadableFieldLabel($target_field_id) . '" (' . $target_entity . ')';
    } catch(Exception $e) {
      Civi::log()->debug('UpdateDateCustomValue Action: Error parsing target field name ('.$e->getMessage().')');
      return;
    }

    if ($action_params['update_operation']==='set') {

      return 'Set '. $target_field . ' to "'. $action_params['update_operand'] . '"';
    }

    try {
      list($source_entity, $source_field_id) = $this->parseRawFieldId($action_params['source_field_id']);
      $source_field = '"' . $this->getHumanReadableFieldLabel($source_field_id) . '" (' . $source_entity . ')';
    } catch(Exception $e) {
      Civi::log()->debug('UpdateDateCustomValue Action: Error parsing source field name ('.$e->getMessage().')');
      return;
    }
    
    $update = empty($action_params['update_operand']) ? '' : ' modifield by "' . $action_params['update_operand'] . '"';

    if ($action_params['update_operation']==='modify') {

      return 'Set '. $target_field .' to the value of ' . $source_field . $update;
    }

    if ($action_params['update_operation']==='max_modify') {
      
      return 'Set ' . $target_field . ' to the Global Maximum value of ' . $source_field . $update;
    }

    if ($action_params['update_operation']==='min_modify') {
      
      return 'Set ' . $target_field . ' to the Global Minimum value of ' . $source_field . $update;
    }

    return 'Error';
  }

  /**
   * Find the human readable label for a field
   * 
   * @param string|int $field_identifier
   * @access protected
   * @return string
   * @throws \CiviCRM_API3_Exception
   */
  protected function getHumanReadableFieldLabel($field_identifier) {

    // Custom fields
    if (is_numeric($field_identifier)) {
      $custom_field = civicrm_api3('CustomField', 'getsingle', [
        'id' => $field_identifier,
      ]);
      return $custom_field['label'];
    }

    // Built in Fields
    return ucwords(str_replace('_', ' ', $field_identifier));
  }
  
}