<?php

final class HeraldPreCommitContentAdapter extends HeraldAdapter {

  private $log;
  private $hookEngine;
  private $changesets;
  private $commitRef;

  public function setPushLog(PhabricatorRepositoryPushLog $log) {
    $this->log = $log;
    return $this;
  }

  public function setHookEngine(DiffusionCommitHookEngine $engine) {
    $this->hookEngine = $engine;
    return $this;
  }

  public function getAdapterApplicationClass() {
    return 'PhabricatorApplicationDiffusion';
  }

  public function getObject() {
    return $this->log;
  }

  public function getAdapterContentName() {
    return pht('Commit Hook: Commit Content');
  }

  public function getFieldNameMap() {
    return array(
    ) + parent::getFieldNameMap();
  }

  public function getFields() {
    return array_merge(
      array(
        self::FIELD_BODY,
        self::FIELD_DIFF_FILE,
        self::FIELD_DIFF_CONTENT,
        self::FIELD_DIFF_ADDED_CONTENT,
        self::FIELD_DIFF_REMOVED_CONTENT,
        self::FIELD_REPOSITORY,
        self::FIELD_PUSHER,
        self::FIELD_PUSHER_PROJECTS,
        self::FIELD_RULE,
      ),
      parent::getFields());
  }

  public function getConditionsForField($field) {
    switch ($field) {
    }
    return parent::getConditionsForField($field);
  }

  public function getActions($rule_type) {
    switch ($rule_type) {
      case HeraldRuleTypeConfig::RULE_TYPE_GLOBAL:
        return array(
          self::ACTION_BLOCK,
          self::ACTION_NOTHING
        );
      case HeraldRuleTypeConfig::RULE_TYPE_PERSONAL:
        return array(
          self::ACTION_NOTHING,
        );
    }
  }

  public function getValueTypeForFieldAndCondition($field, $condition) {
    return parent::getValueTypeForFieldAndCondition($field, $condition);
  }

  public function getPHID() {
    return $this->getObject()->getPHID();
  }

  public function getHeraldName() {
    return pht('Push Log');
  }

  public function getHeraldField($field) {
    $log = $this->getObject();
    switch ($field) {
      case self::FIELD_BODY:
        return $this->getCommitRef()->getMessage();
      case self::FIELD_DIFF_FILE:
        return $this->getDiffContent('name');
      case self::FIELD_DIFF_CONTENT:
        return $this->getDiffContent('*');
      case self::FIELD_DIFF_ADDED_CONTENT:
        return $this->getDiffContent('+');
      case self::FIELD_DIFF_REMOVED_CONTENT:
        return $this->getDiffContent('-');
      case self::FIELD_REPOSITORY:
        return $this->hookEngine->getRepository()->getPHID();
      case self::FIELD_PUSHER:
        return $this->hookEngine->getViewer()->getPHID();
      case self::FIELD_PUSHER_PROJECTS:
        return $this->hookEngine->loadViewerProjectPHIDsForHerald();
    }

    return parent::getHeraldField($field);
  }

  public function applyHeraldEffects(array $effects) {
    assert_instances_of($effects, 'HeraldEffect');

    $result = array();
    foreach ($effects as $effect) {
      $action = $effect->getAction();
      switch ($action) {
        case self::ACTION_NOTHING:
          $result[] = new HeraldApplyTranscript(
            $effect,
            true,
            pht('Did nothing.'));
          break;
        case self::ACTION_BLOCK:
          $result[] = new HeraldApplyTranscript(
            $effect,
            true,
            pht('Blocked push.'));
          break;
        default:
          throw new Exception(pht('No rules to handle action "%s"!', $action));
      }
    }

    return $result;
  }

  private function getDiffContent($type) {
    if ($this->changesets === null) {
      try {
        $this->changesets = $this->hookEngine->loadChangesetsForCommit(
          $this->log->getRefNew());
      } catch (Exception $ex) {
        $this->changesets = $ex;
      }
    }

    if ($this->changesets instanceof Exception) {
      $ex_class = get_class($this->changesets);
      $ex_message = $this->changesets->getmessage();
      if ($type === 'name') {
        return array("<{$ex_class}: {$ex_message}>");
      } else {
        return array("<{$ex_class}>" => $ex_message);
      }
    }

    $result = array();
    if ($type === 'name') {
      foreach ($this->changesets as $change) {
        $result[] = $change->getFilename();
      }
    } else {
      foreach ($this->changesets as $change) {
        $lines = array();
        foreach ($change->getHunks() as $hunk) {
          switch ($type) {
            case '-':
              $lines[] = $hunk->makeOldFile();
              break;
            case '+':
              $lines[] = $hunk->makeNewFile();
              break;
            case '*':
            default:
              $lines[] = $hunk->makeChanges();
              break;
          }
        }
        $result[$change->getFilename()] = implode('', $lines);
      }
    }

    return $result;
  }

  private function getCommitRef() {
    if ($this->commitRef === null) {
      $this->commitRef = $this->hookEngine->loadCommitRefForCommit(
        $this->log->getRefNew());
    }
    return $this->commitRef;
  }

}