<?php

final class AphrontUnhandledExceptionResponse
  extends AphrontStandaloneHTMLResponse {

  private $exception;
  private $showStackTraces;

  public function setShowStackTraces($show_stack_traces) {
    $this->showStackTraces = $show_stack_traces;
    return $this;
  }

  public function getShowStackTraces() {
    return $this->showStackTraces;
  }

  public function setException($exception) {
    // NOTE: We accept an Exception or a Throwable.

    // Log the exception unless it's specifically a silent malformed request
    // exception.

    $should_log = true;
    if ($exception instanceof AphrontMalformedRequestException) {
      if ($exception->getIsUnlogged()) {
        $should_log = false;
      }
    }

    if ($should_log) {
      phlog($exception);
    }

    $this->exception = $exception;
    return $this;
  }

  public function getHTTPResponseCode() {
    return 500;
  }

  protected function getResources() {
    return array(
      'css/application/config/config-template.css',
      'css/application/config/unhandled-exception.css',
    );
  }

  protected function getResponseTitle() {
    $ex = $this->exception;

    if ($ex instanceof AphrontMalformedRequestException) {
      return $ex->getTitle();
    } else {
      return pht('Unhandled Exception');
    }
  }

  protected function getResponseBodyClass() {
    return 'unhandled-exception';
  }

  private function getExceptionList() {
    return $this->expandException($this->exception);
  }

  private function expandException($root) {
    if ($root instanceof PhutilAggregateException) {
      $list = array();

      $list[] = $root;

      foreach ($root->getExceptions() as $ex) {
        foreach ($this->expandException($ex) as $child) {
          $list[] = $child;
        }
      }

      return $list;
    }

    return array($root);
  }

  protected function getResponseBody() {
    $body = array();

    foreach ($this->getExceptionList() as $ex) {
      $body[] = $this->newHTMLMessage($ex);
    }

    return $body;
  }

  private function newHTMLMessage($ex) {
    if ($ex instanceof AphrontMalformedRequestException) {
      $title = $ex->getTitle();
    } else {
      $title = get_class($ex);
    }

    $body = $ex->getMessage();
    $body = phutil_escape_html_newlines($body);

    $classes = array();
    $classes[] = 'unhandled-exception-detail';

    $stack = null;
    if ($this->getShowStackTraces()) {
      try {
        $stack = id(new AphrontStackTraceView())
          ->setTrace($ex->getTrace());

        $stack = hsprintf('%s', $stack);

        $stack = phutil_tag(
          'div',
          array(
            'class' => 'unhandled-exception-stack',
          ),
          $stack);

        $classes[] = 'unhandled-exception-with-stack';
      } catch (Exception $trace_exception) {
        $stack = null;
      } catch (Throwable $trace_exception) {
        $stack = null;
      }
    }

    return phutil_tag(
      'div',
      array(
        'class' => implode(' ', $classes),
      ),
      array(
        phutil_tag(
          'h1',
          array(
            'class' => 'unhandled-exception-title',
          ),
          $title),
        phutil_tag(
          'div',
          array(
            'class' => 'unhandled-exception-body',
          ),
          $body),
        $stack,
      ));
  }

  protected function buildPlainTextResponseString() {
    $messages = array();

    foreach ($this->getExceptionList() as $exception) {
      $messages[] = $this->newPlainTextMessage($exception);
    }

    return implode("\n\n", $messages);
  }

  private function newPlainTextMessage($exception) {
    return pht(
      '%s: %s',
      get_class($exception),
      $exception->getMessage());
  }

}