WordPress Pluginでテンプレートを操作

wp-content_plugins_sample_sample.php

<?php
add_action('template_redirect', 'sample_action');

function sample_action() {
  global $wp;
  echo '<pre>';
  var_dump($wp->query_vars);
  echo '</pre>';
  
  $template = _parse_request_uri($wp->query_vars);
  if ($template && file_exists($template)) {
    include $template;
    exit;
  }
}

function _parse_request_uri($qv) {
  $result = false;
  
  if (count($qv) <= 0)
   return false;
   
  if ($qv['category_name'] === 'sample') {
    if (count($qv) === 1) {
      $result = 'index';
    }
    elseif ($qv['name'] === 'search' && isset($_GET['q']) && mb_strlen($_GET['q']) > 0) {
      // serching function
      $result = 'search';
    }
    elseif (preg_match("/^[0-9]+$/", $qv['name'])) {
      // find function
      $result = 'single';
    }
    else {
      return false;
    }
  } else {
    return false;
  }
  
  if ($result) {
    return TEMPLATEPATH . '/sample/' . $result . '.php';
  } else {
    return false;
  }
}