<?php
namespace {

$GLOBALS['TASKMAN_TASKS'] = array();
$GLOBALS['TASKMAN_CLOSURES'] = array();
$GLOBALS['TASKMAN_STACK'] = array();
$GLOBALS['TASKMAN_TASK_ALIASES'] = array();
$GLOBALS['TASKMAN_LOG_LEVEL'] = 1; //0 - important, 1 - normal, 2 - debug
$GLOBALS['TASKMAN_NO_DEPS'] = false;
$GLOBALS['TASKMAN_SCRIPT'] = '';
$GLOBALS['TASKMAN_CURRENT_TASK'] = null;
$GLOBALS['TASKMAN_HELP_FUNC'] = 'taskman_default_usage';
$GLOBALS['TASKMAN_LOGGER'] = '_taskman_default_logger';
$GLOBALS['TASKMAN_ERROR_HANDLER'] = null;
$GLOBALS['TASKMAN_START_TIME'] = 0;

class TaskmanException extends Exception
{}

class TaskmanTask
{
  private $func;
  private $name;
  private $file;
  private $line;
  private $props = array();
  private $is_running = false;
  private $has_run = array();
  private $args = array();

  function __construct($func, $name = null, $props = null)
  {
    if(!is_callable($func))
      throw new TaskmanException("Task '{$func}' is non-callable");

    $refl = new ReflectionFunction($func);
    $this->file = $refl->getFileName();
    $this->line = $refl->getStartLine();

    if(is_string($func) && $name === null && $props === null)
    {
      $this->name = self::extractName($func);
      $this->_parseProps($refl);
    }
    else
    {
      $this->name = $name;
      $this->props = $props;
    }

    $this->func = $func;
  }

  function validate()
  {                       
    try
    {
      foreach($this->_getBeforeDeps() as $dep_task)
        taskman_gettask($dep_task);

      foreach($this->_getDeps() as $dep_task)
        taskman_gettask($dep_task);

      foreach($this->_getAfterDeps() as $dep_task)
        taskman_gettask($dep_task);
    }
    catch(Exception $e)
    {
      throw new Exception("Task '{$this->name}' validation error: " . $e->getMessage());
    }
  }

  function getName()
  {
    return $this->name;    
  }

  function getFile()
  {
    return $this->file;
  }

  function getLine()
  {
    return $this->line;
  }

  function getFunc()
  {
    return $this->func;
  }

  function getArgs()
  {
    return $this->args;
  }

  function getAliases()
  {
    $alias = $this->getPropOr("alias", "");
    if(is_array($alias))
      return $alias;
    else if($alias && is_string($alias))
      return explode(",", $alias);
    else
      return array();
  }

  function run($args = array())
  {
    global $TASKMAN_CURRENT_TASK;
    global $TASKMAN_STACK;
    global $TASKMAN_NO_DEPS;
    global $TASKMAN_START_TIME;

    $args_str = serialize($args);

    if((isset($this->has_run[$args_str]) && $this->has_run[$args_str]) || 
       $this->is_running)
      return;

    $this->is_running = true;
    $this->args = $args;

    try
    {
      if(!$TASKMAN_NO_DEPS)
      {
        taskman_runtasks($this->_getBeforeDeps());
        taskman_runtasks($this->_getDeps());
      }

      taskman_sysmsg("************************ Running task '" . $this->getName() . "' ************************\n");

      $bench = microtime(true);

      $TASKMAN_CURRENT_TASK = $this;
      $TASKMAN_STACK[] = $this;
      call_user_func_array($this->func, array($this->args));
      array_pop($TASKMAN_STACK);

      if(!$TASKMAN_NO_DEPS)
        taskman_runtasks($this->_getAfterDeps());

      taskman_sysmsg("************************* '" . $this->getName() . "' done (" . 
                     round(microtime(true)-$bench,2) . '/' .round(microtime(true)-$TASKMAN_START_TIME,2) . " sec.)*************************\n");

      $this->has_run[$args_str] = true;
      $this->is_running = false;
    }
    catch(Exception $e)
    {
      $error_handler = $GLOBALS['TASKMAN_ERROR_HANDLER'];
      if($error_handler)
        $error_handler($e);
      else
        throw $e;
    }
  }

  private function _getBeforeDeps()
  {
    return $this->_collectRelatedTasks("before");
  }

  private function _getAfterDeps()
  {
    return $this->_collectRelatedTasks("after");
  }

  private function _collectRelatedTasks($prop_name)
  {
    $arr = array();
    foreach(taskman_gettasks() as $task_obj)
    {
      if($this->getName() == $task_obj->getName())
        continue;

      $value = $task_obj->getPropOr($prop_name, "");
      if($value == $this->getName() || in_array($value, $this->getAliases()))
        $arr[] = $task_obj;
    }
    return $arr;
  }

  private function _getDeps()
  {
    $deps = $this->getPropOr('deps', "");
    if(is_array($deps))
      return $deps;
    else if($deps && is_string($deps))
      return _taskman_parse_taskstr($deps);
    return array();
  }

  private function _parseProps(ReflectionFunction $refl)
  {
    if(preg_match_all('~@(\S+)([^\n]+)?\n~', $refl->getDocComment(), $matches))
    {
      foreach($matches[1] as $idx => $match)
        $this->props[$match] = trim($matches[2][$idx]);
    }
  }

  static function extractName($func)
  {
    if(strpos($func, "task_") === 0)
      return substr($func, strlen('task_'), strlen($func));
    else if(strpos($func, 'taskman\task_') === 0)
      return substr($func, strlen('taskman\task_'), strlen($func));
  }

  function getPropOr($name, $def)
  {
    return isset($this->props[$name]) ? $this->props[$name] : $def;
  }

  function getProp($name)
  {
    return $this->getPropOr($name, null);
  }

  function hasProp($name)
  {
    return isset($this->props[$name]);
  }

  function getProps()
  {
    return $this->props;
  }
}

function taskman_reset()
{
  $GLOBALS['TASKMAN_TASKS'] = array();
  $GLOBALS['TASKMAN_TASK_ALIASES'] = array();
  $GLOBALS['TASKMAN_CURRENT_TASK'] = null;
  $GLOBALS['TASKMAN_CONFIG'] = array();

  _taskman_collecttasks();
}

function taskman_str($str)
{
  if(strpos($str, '%') === false)
    return $str;

  $str = preg_replace_callback(
          '~%\(([^\)]+)\)%~',
          function($m) { return taskman_prop($m[1]); },
          $str
        );
  return $str;
}

function taskman_run($argv = array(), $help_func = null, $proc_argv = true)
{
  $GLOBALS['TASKMAN_START_TIME'] = microtime(true);

  if($help_func)
    $GLOBALS['TASKMAN_HELP_FUNC'] = $help_func;
  if($proc_argv)
    taskman_process_argv($argv);
  $GLOBALS['TASKMAN_SCRIPT'] = array_shift($argv);

  _taskman_collecttasks();

  $always_tasks = array();
  $default_task = null;
  foreach(taskman_gettasks() as $task_obj)
  {
    if($task_obj->hasProp('always'))
      array_unshift($always_tasks, $task_obj);
    if($task_obj->hasProp('default'))
    {
      if($default_task)
        throw new TaskmanException("Assigned default task '" . $default_task->getName() . "' conflicts with '" . $task_obj->getName() . "'");
      else
        $default_task = $task_obj;
    }
  }

  foreach($always_tasks as $always_task)
    $always_task->run(array());

  if(sizeof($argv) > 0)
  {
    $task_str = array_shift($argv);
    $tasks = _taskman_parse_taskstr($task_str);

    if(count($tasks) == 1 && !taskman_isset_task($tasks[0]))
    {
      $pattern = $tasks[0];
      if($pattern[0] == '~')
      {
        $pattern = substr($pattern, 1, strlen($pattern) - 1);
        $is_similar = true;
      }
      elseif(substr($pattern, -1, 1) == '~')
      {
        $pattern = substr($pattern, 0, strlen($pattern) - 1);
        $is_similar = true;
      }
      else
        $is_similar = false;
      $hints = taskman_get_hints($pattern);

      if($is_similar && count($hints) == 1)
        $tasks = $hints;
      else
      {
        printf("ERROR! Task %s not found\n", $tasks[0]);
        if($hints)
        {
          printf("Similar tasks:\n");
          foreach($hints as $hint)
            printf("    %s\n", $hint);
        }
        exit(1);
      }
    }

    taskman_runtasks($tasks, $argv);
  }
  else if($default_task)
    $default_task->run($argv);

  taskman_sysmsg("************************ All done (".round(microtime(true)-$GLOBALS['TASKMAN_START_TIME'],2)." sec.)************************\n");
}

function taskman_isset_task($task)
{
  global $TASKMAN_TASKS;
  global $TASKMAN_TASK_ALIASES;
  return isset($TASKMAN_TASKS[$task]) || isset($TASKMAN_TASK_ALIASES[$task]);
}

function taskman_get_hints($task)
{
  global $TASKMAN_TASKS;
  global $TASKMAN_TASK_ALIASES;
  $tasks = array_merge(array_keys($TASKMAN_TASKS), array_keys($TASKMAN_TASK_ALIASES));
  $found = array_filter($tasks, function($v) use($task) { return strpos($v, $task) === 0; });
  $found = array_merge($found, array_filter($tasks, function($v) use($task) { $pos = strpos($v, $task); return $pos !== false && $pos > 0; }));
  return $found;
}

function taskman_process_argv(&$argv)
{
  global $TASKMAN_LOG_LEVEL;
  global $TASKMAN_BATCH;
  global $TASKMAN_NO_DEPS;

  $filtered = array();
  $process_defs = false;
  for($i=0;$i<sizeof($argv);++$i)
  {
    $v = $argv[$i];

    if($v == '--')
    {
      for($j=$i+1;$j<sizeof($argv);++$j)
        $filtered[] = $argv[$j];
      break;
    }
    else if($v == '-D')
    {
      $process_defs = true;
    }
    else if($v == '-V')
    {
      $TASKMAN_LOG_LEVEL = 2;
    }
    else if($v == '-q')
    {
      $TASKMAN_LOG_LEVEL = 0;
    }
    else if($v == '-b')
    {
      $TASKMAN_LOG_LEVEL = -1;
    }
    else if($v == '-O')
    {
      $TASKMAN_NO_DEPS = true;
    }
    else if($v == '-c')
    {
      if(!isset($argv[$i+1]))
        throw new TaskmanException("Configuration file(-c option) is missing");
      require_once($argv[$i+1]);
      ++$i;
    }
    else if($process_defs)
    {
      $eq_pos = strpos($v, '=');
      if($eq_pos !== false)
      {
        $def_name = substr($v, 0, $eq_pos);
        $def_value = substr($v, $eq_pos+1);

        if(in_array(strtolower($def_value), array('yes', 'true'), true/*strict*/))
          $def_value = true;
        else if(in_array(strtolower($def_value), array('no', 'false'), true/*strict*/))
          $def_value = false;
      }
      else
      {
        $def_name = $v;
        $def_value = 1;
      }

      taskman_sysmsg("Setting prop $def_name=" . (is_bool($def_value) ? ($def_value ? 'true' : 'false') : $def_value) . "\n");
      taskman_propset($def_name, $def_value);
      
      $process_defs = false;
    }
    else
      $filtered[] = $v;
  }
  $argv = $filtered;
}

function _taskman_collecttasks()
{
  global $TASKMAN_TASKS;
  global $TASKMAN_TASK_ALIASES;

  $TASKMAN_TASKS = array();
  $TASKMAN_TASK_ALIASES = array();

  $cands = _taskman_get_task_candidates();
  foreach($cands as $name => $args)
  {
    if(isset($TASKMAN_TASKS[$name]))
      throw new TaskmanException("Task '$name' is already defined");

    $task = null;
    if(is_string($args))
    { 
      $task = new TaskmanTask($args);
    }
    else if(is_array($args))
    {
      $props = array();
      if(sizeof($args) > 2)
      {
        $props = $args[1];
        $func = $args[2];
      }
      else
        $func = $args[1];

      $task = new TaskmanTask($func, $name, $props);
    }
    else
      throw new Exception("Task '$name' is invalid");

    $TASKMAN_TASKS[$name] = $task; 

    foreach($task->getAliases() as $alias)
    {
      if(isset($TASKMAN_TASKS[$alias]) || isset($TASKMAN_TASK_ALIASES[$alias]))
        throw new TaskmanException("Alias '$alias' is already defined for task '$name'");
      $TASKMAN_TASK_ALIASES[$alias] = $task; 
    }
  }

  foreach($TASKMAN_TASKS as $task)
    $task->validate();
}

function _taskman_get_task_candidates()
{
  global $TASKMAN_CLOSURES;

  $cands = array();

  //1. get tasks defined as regular functions
  $funcs = get_defined_functions();
  foreach($funcs['user'] as $func)
  {
    $name = TaskmanTask::extractName($func);
    if(!$name)
      continue;
    $cands[$name] = $func;
  }

  //2. get tasks defined as closures
  foreach($TASKMAN_CLOSURES as $name => $args)
  {
    if(isset($cands[$name]))
      throw new Exception("Task '$name' is already defined");
    $cands[$name] = $args;
  }

  ksort($cands);

  return $cands;
}

function taskman_gettasks()
{
  global $TASKMAN_TASKS;
  return $TASKMAN_TASKS;
}

function taskman_gettask($task)
{
  global $TASKMAN_TASKS;
  global $TASKMAN_TASK_ALIASES;

  if(!is_scalar($task))
    throw new TaskmanException("Bad task name");

  if(isset($TASKMAN_TASKS[$task]))
    return $TASKMAN_TASKS[$task];

  if(isset($TASKMAN_TASK_ALIASES[$task]))
    return $TASKMAN_TASK_ALIASES[$task];

  throw new TaskmanException("Task with name/alias '{$task}' does not exist");
}

function _taskman_parse_taskstr($str)
{
  $task_spec = array();
  $items = explode(',', $str);
  foreach($items as $item)
  {
    $args = null;
    $task = $item;
    if(strpos($item, ' ') !== false)
      @list($task, $args) = explode(' ', $item, 2);

    if($args)
      $task_spec[] = array($task, explode(' ', $args));
    else
      $task_spec[] = $task;
  }
  return $task_spec;
}

function taskman_runtask($task, $args = array())
{
  if($task instanceof TaskmanTask)
    $task_obj = $task;
  else
    $task_obj = taskman_gettask($task);

  $task_obj->run($args);
}

function taskman_runtasks($tasks, $args = array())
{
  foreach($tasks as $task_spec)
  {
    if(is_array($task_spec))
      taskman_runtask($task_spec[0], $task_spec[1]);
    else
      taskman_runtask($task_spec, $args);
  }
}

function taskman_current_task()
{
  global $TASKMAN_CURRENT_TASK;
  return $TASKMAN_CURRENT_TASK;
}

function taskman_shell_get($cmd, $as_string = true)
{
  exec($cmd, $out, $code);
  if($code !== 0)
    throw new Exception("Error($code) executing shell cmd '$cmd'");
  return $as_string ? implode("", $out) : $out;
}

function taskman_shell_ensure($cmd, &$out=null)
{
  taskman_shell($cmd, $ret, $out);
  if($ret != 0)
    throw new TaskmanException("Shell execution error(exit code $ret)");
}

function taskman_shell($cmd, &$ret=null, &$out=null)
{
  taskman_msg(" shell: $cmd\n");
  taskman_msg(" ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n");
  
  if(func_num_args() < 3)
    system($cmd, $ret);
  else
    _taskman_execute_proc_cmd($cmd, $ret, $out);
}

function _taskman_execute_proc_cmd($cmd, &$ret, &$out)
{
  //TODO: do we really need to redirect error stream?
  $proc = popen("$cmd 2>&1", 'r');

  $log = '';
  //TODO: how can this be?
  if(is_string($proc))
  {
    $log = $proc;
    taskman_log($log, 1);
  }
  else
  {
    while($logline = fgets($proc))
    {
      $log .= $logline;
      taskman_log($logline, 1);
    }
  }
  $out = explode("\n", $log);
  $ret = pclose($proc);
}

function taskman_dmsg($msg)
{
  taskman_log($msg, 2);
}

function taskman_msg($msg)
{
  taskman_log($msg, 1);
}

function taskman_sysmsg($msg)
{
  taskman_log($msg, 0);
}

function taskman_log($msg, $level = 1)
{
  global $TASKMAN_LOG_LEVEL;

  if($TASKMAN_LOG_LEVEL < $level)
    return;

  $logger = $GLOBALS['TASKMAN_LOGGER'];
  call_user_func_array($logger, array($msg));
}

function _taskman_default_logger($msg)
{
  echo $msg;
}

function _taskman_resolve_callable_prop($name)
{
  $prop = $GLOBALS['TASKMAN_PROP_' . $name];
  if(!($prop instanceof \Closure))
    return;
  $value = $prop();
  $GLOBALS['TASKMAN_PROP_' . $name] = $value;
}

function taskman_prop($name)
{
  if(!isset($GLOBALS['TASKMAN_PROP_' . $name]))
    throw new TaskmanException("Property '$name' is not set");
  _taskman_resolve_callable_prop($name);
  return $GLOBALS['TASKMAN_PROP_' . $name];
}

function taskman_propor($name, $def)
{
  if(!isset($GLOBALS['TASKMAN_PROP_' . $name]))
    return $def;
  _taskman_resolve_callable_prop($name);
  return $GLOBALS['TASKMAN_PROP_' . $name];
}

function taskman_propset($name, $value)
{
  $GLOBALS['TASKMAN_PROP_' . $name] = $value;
}

function taskman_propadd($name, $value)
{
  if(!isset($GLOBALS['TASKMAN_PROP_' . $name]))
    $GLOBALS['TASKMAN_PROP_' . $name] = '';
  _taskman_resolve_callable_prop($name);
  $GLOBALS['TASKMAN_PROP_' . $name] .= $value;
}

function taskman_propsetor($name, $value)
{
  if(!isset($GLOBALS['TASKMAN_PROP_' . $name]))
    $GLOBALS['TASKMAN_PROP_' . $name] = $value;
}

function taskman_propunset($name)
{
  unset($GLOBALS['TASKMAN_PROP_' . $name]);
}

function taskman_getprops()
{
  $props = array();
  foreach($GLOBALS as $key => $value)
  {
    if(($idx = strpos($key, 'TASKMAN_PROP_')) === 0)
    {
      $name = substr($key, strlen('TASKMAN_PROP_'));
      $props[$name] = taskman_prop($name);
    }
  }
  return $props;
}

function taskman_isprop($name)
{
  return isset($GLOBALS['TASKMAN_PROP_' . $name]);
}

function taskman_default_usage($script_name = "<taskman-script>")
{
  echo "\nUsage:\n $script_name [OPTIONS] <task-name1>[,<task-name2>,..] [-D PROP1=value [-D PROP2]]\n\n";
  echo "Available options:\n";
  echo " -c    specify PHP script to be included (handy for setting props,config options,etc)\n";
  echo " -V    be super verbose\n";
  echo " -q    be quite, only system messages\n";
  echo " -b    batch mode: be super quite, don't even output any system messages\n";
  echo " --    pass all options verbatim after this mark\n";
}

/**
 * @desc Shows this help
 */
function task_help($args = array())
{
  $filter = '';
  if(isset($args[0]))
    $filter = $args[0];

  $maxlen = -1;
  $tasks = array();
  $all = taskman_gettasks();
  foreach($all as $task)
  {
    if($filter && (strpos($task->getName(), $filter) === false && strpos($task->getPropOr("alias", ""), $filter) === false))
      continue;

    if(strlen($task->getName()) > $maxlen)
      $maxlen = strlen($task->getName());

    $tasks[] = $task;
  }

  if(!$args)
  {
    $help_func = $GLOBALS['TASKMAN_HELP_FUNC'];
    $help_func();
    echo "\n";
  }

  echo "Available tasks:\n";
  foreach($tasks as $task)
  {
    $props_string = '';
    $pad = $maxlen - strlen($task->getName());
    foreach($task->getProps() as $name => $value)
    {
      $props_string .= str_repeat(" ", $pad) .'  @' . $name . ' ' . (is_string($value) ? $value : json_encode($value)) . "\n";
      $pad = $maxlen + 1;
    }
    $props_string = rtrim($props_string);

    echo "---------------------------------\n";
    $file = $task->getFile();
    $line = $task->getLine();
    echo " " . $task->getName() .  $props_string . " ($file@$line)\n";
  }
  echo "\n";
}


/**
 * @desc Encodes tasks as json array
 */
function task_json()
{
  $json = array();
  foreach(taskman_gettasks() as $task)
  {
    $json[$task->getName()] = $task->getProps();
  }
  echo json_encode($json);
}

} //namespace global

namespace taskman {

function get($name)
{
  return \taskman_prop($name);
}

function getor($name, $def)
{
  return \taskman_propor($name, $def);
}

function set($name, $value)
{
  \taskman_propset($name, $value);
}

function setor($name, $value)
{
  \taskman_propsetor($name, $value);
}

function add($name, $value)
{
  \taskman_propadd($name, $value);
}

function is($name)
{
  return \taskman_isprop($name);
}

function del($name)
{
  \taskman_propunset($name);
}

function props()
{
  return \taskman_getprops();
}

function task($name)
{
  global $TASKMAN_CLOSURES;

  $args = func_get_args();
  $TASKMAN_CLOSURES[$name] = $args; 
}

function run($task, array $args = array())
{
  \taskman_runtask($task, $args);
}

function msg_dbg($msg)
{
  \taskman_dmsg($msg);
}

function msg($msg)
{
  \taskman_msg($msg);
}

function msg_sys($msg)
{
  \taskman_sysmsg($msg);
}

function shell($cmd, &$out=null)
{
  \taskman_shell_ensure($cmd, $out);
}

function shell_try($cmd, &$ret=null, &$out=null)
{
  \taskman_shell($cmd, $ret, $out);
}

function _($str) 
{ 
  return \taskman_str($str); 
}

function main($argv = array(), $help_func = null, $proc_argv = true)
{
  \taskman_run($argv, $help_func, $proc_argv);
}

function usage($script_name = "<taskman-script>")
{
  \taskman_default_usage($script_name);
}

} //namespace taskman
//}}}