<?php
namespace taskman;
use Exception;

task('bhl_clean', function()
{
  bhl_clean();
});

task('bhl_clean_cache', function()
{
  bhl_clean_cache();
});

class BhlProj
{
  public static ?BhlProj $active = null;

  public string $file_path;
  public array $inc_dirs = array();
  public array $src_dirs = array();
  public array $defines = array();
  public array $bindings_sources;
  public array $postproc_sources;
  public string $postproc_dll;
  public string $bindings_dll;
  public string $result_file;
  public string $error_file;
  public string $tmp_dir;
  public int $max_threads;
  public bool $deterministic;

  function getIncPath() : array
  {
    if($this->inc_dirs)
      return $this->inc_dirs;
    return $this->src_dirs;
  }
}

function bhl_proj_file() : string
{
  return get('BHL_PROJ_FILE');
}

function bhl_proj_load(string $proj_file) : BhlProj
{
  $arr = json_decode(ensure_read($proj_file), true);
  if(!$arr)
    throw new Exception("Bad bhl project file: $proj_file");

  $proj = new BhlProj();
  foreach($arr as $k => $v) 
    $proj->{$k} = $v;

  //NOTE: adding path to the file for further convenience
  $proj->file_path = $proj_file; 

  foreach($proj->inc_dirs as $k => $v)
    $proj->inc_dirs[$k] = _bhl_make_abs_path($proj_file, $v);

  foreach($proj->src_dirs as $k => $v)
    $proj->src_dirs[$k] = _bhl_make_abs_path($proj_file, $v);

  foreach($proj->bindings_sources as $k => $v)
    $proj->bindings_sources[$k] = _bhl_make_abs_path($proj_file, $v);
  $proj->bindings_dll = _bhl_make_abs_path($proj_file, $proj->bindings_dll);

  if(isset($proj->postproc_sources))
  {
    foreach($proj->postproc_sources as $k => $v)
      $proj->postproc_sources[$k] = _bhl_make_abs_path($proj_file, $v);
  }

  if(isset($proj->postproc_dll))
    $proj->postproc_dll = _bhl_make_abs_path($proj_file, $proj->postproc_dll);

  $proj->result_file = _bhl_make_abs_path($proj_file, $proj->result_file);
  $proj->error_file = _bhl_make_abs_path($proj_file, $proj->error_file);
  $proj->tmp_dir = _bhl_make_abs_path($proj_file, $proj->tmp_dir);

  return $proj;
}

function bhl_proj_set_active(BhlProj $proj) : ?BhlProj
{
  $prev = BhlProj::$active;
  BhlProj::$active = $proj;
  return $prev;
}

function bhl_proj() : BhlProj
{
  if(BhlProj::$active == null)
  {
    $proj = bhl_proj_load(bhl_proj_file());
    BhlProj::$active = $proj;
  }
  return BhlProj::$active;
}

function _bhl_make_abs_path(string $proj_file, string $path) : string
{
  if($path && $path[0] == '.')
    return dirname($proj_file) . '/' . $path;
  else
    return $path;
}

function bhl_result_file() : string
{
  return bhl_proj()->result_file;
}

function bhl_dir() : string
{
  global $GAME_ROOT;
  return "$GAME_ROOT/composer/vendor/bit/bhl";
}

function bhl_shell(string $cmd, &$ret_var, &$ret_out)
{
  shell_try(bhl_dir()."/bhl $cmd", $ret_var, $ret_out);
}

function bhl_shell_ensure(string $cmd)
{
  bhl_shell($cmd, $ret_var, $ret_out);
  if($ret_var !== 0)
    throw new Exception("Error executing shell cmd: $ret_var");
}

function bhl_scan_files() : array
{
  return scan_files_rec(bhl_proj()->src_dirs, array('.bhl'));
}

function bhl_run(bool $debug = true, bool $force = false, bool $exit_on_err = true)
{
  global $GAME_ROOT;

  $bhl_proj = bhl_proj();
  $result_file = $bhl_proj->result_file;

  if($force || need_to_regen($result_file, bhl_scan_files()))
  {
    bhl_shell("compile -p " . $bhl_proj->file_path . " " .
      ($debug ? " -d" : "") . " " .
      ($force || !getor("BHL_USE_CACHE", true) ? " -C" : ""),
      $ret_var, $ret_out
    );

    if($ret_var != 0)
    {
      bhl_handle_error_result($ret_out, $bhl_proj->error_file, $exit_on_err);
      if(!$exit_on_err)
        return false;
    }
    else
      echo "BHL BUNDLE: total " . kb_len(filesize($result_file)) . ", CRC " . hexdec(hash_file('CRC32', $result_file, false)) . "\n"; 
  }

  @touch($result_file);
}

function bhl_handle_error_result(array $ret_out, string $err_file, bool $exit = true)
{
  if(!is_file($err_file))
  {
    stderr("Something went wrong: " . implode("\n", $ret_out));
    if($exit)
      exit(1);
  }

  $history = array();
  $err_lines = file($err_file);
  $err_count = 0;
  foreach($err_lines as $err)
  {
    $jerr = json_decode($err);
    if(!$jerr)
    {
      stderr("Something went wrong, bhl error is in invalid format: $err\n");
      continue;
    }

    $file = $jerr->file;
    //let's show only one error per file's line
    if(isset($history[$file.$jerr->line]))
      continue;
    $history[$file.$jerr->line] = true;
    ++$err_count;
    stderr("BHL ERROR (#$err_count): " . $jerr->error . " \nin '$file', line {$jerr->line}\n");
    if(file_exists($file))
      stderr(bhl_show_position($jerr->line, $jerr->column, file($file)) . "\n");
  }
  if($err_lines && $exit)
    exit(1);
}

function bhl_clean()
{
  bhl_clean_cache();
  bhl_shell_ensure("clean");
}

function bhl_clean_cache()
{
  ensure_rm(bhl_proj()->tmp_dir);
}

function bhl_show_position(int $line, int $row, array $lines) : string
{
  if($line > 0 && $line <= count($lines))
  {
    //handling tabs
    $hint = str_replace("\t", "    ", $lines[$line-1]);
    for($c=0;$c<$row;++$c)
    {
      if($lines[$line-1][$c] === "\t")
        $hint .= "----";
      else
        $hint .= "-";
    }
    $hint .= "^";
    return $hint;
  }
  else
    return "??? @($line:$row)";
}

function bhl_line_row_to_pos(string $file, int $line, int $row) : ?int
{
  $pos = 0;
  $lines = file($file);
  //something went wrong
  if($line <= 0 || $line > count($lines))
    return null;
  for($i=0;$i<($line-1);++$i)
    $pos += strlen($lines[$i]);
  $pos += $row;
  return $pos;
}

function bhl_map_module_to_file(string $module) : ?string
{
  $bhl_proj = bhl_proj();
  foreach($bhl_proj->getIncPath() as $dir)
  {
    $tmp = $dir.'/'.$module.'.bhl';
    if(file_exists($tmp))
      return $tmp;
  }
  return null;
}

function bhl_validate_func_ref(string $module_file, string $func_full_name, array $signature)
{
  if(sizeof($signature) == 0)
    throw new Exception("Signature is invalid");

  $name_items = explode('.', $func_full_name);
  $func = array_pop($name_items);
  $namespace = implode('.', $name_items);

  $module_src = file_get_contents($module_file);
  $module_src = _bhl_remove_comments($module_src);

  if(!$module_src)
    throw new Exception("Bad module file '{$module_file}'");

  $module_chunks = array();
  if($namespace)
  {
    $ns_chunks = _bhl_split_by_namespaces($module_src);
    if(count($ns_chunks) == 0)
      throw new Exception("No namespaces found in '$module_file'");

    foreach($ns_chunks as $ns => $ns_src)
    {
      if($ns === $namespace)
        $module_chunks[] = $ns_src;
    }

    if(count($module_chunks) == 0)
      throw new Exception("Namespace '$namespace' for func '$func_full_name' not found in '$module_file'");
  }
  else
    $module_chunks[] = $module_src;

  $signature_pattern = '';
  $signature_pattern .= '~func\s+';
  if($signature[0] !== 'void')
  {
    $signature_pattern .= preg_quote($signature[0]);
    $signature_pattern .= '\s+';
  }
  $signature_pattern .= $func;
  $signature_pattern .= '\s*\(';
  array_shift($signature);
  foreach($signature as $type)
  {
    $signature_pattern .= '\s*';
    $signature_pattern .= preg_quote($type);
    $signature_pattern .= '\s*\S+';
    $signature_pattern .= '\s*,';
  }
  $signature_pattern = rtrim($signature_pattern, '\s*,');
  $signature_pattern .= '\s*\)';
  $signature_pattern .= '~';

  foreach($module_chunks as $module_chunk_src)
  {
    if(preg_match($signature_pattern, $module_chunk_src))
      return;
  }

  throw new Exception("Func '$func_full_name(".implode(',', $signature).")' not found in '$module_file'");
}

function _bhl_remove_comments(string $txt) : string
{
  //block comments
  if(strpos($txt, '/*') !== false)
  {
    $regex = '~/\*.*?\*/~s';
    $txt = preg_replace_callback(
      $regex, 
      //preserve the new lines for better error reporting
      function($m) { return str_repeat("\n", substr_count($m[0], "\n")); },
      $txt);
  }
  //line comments
  $txt = preg_replace("~\s*(?<!:)//.*~", "\n", $txt);
  return $txt;
}

function _bhl_split_by_namespaces(string $src) : array
{
  $nss = array();

  $chunks = preg_split('~^\s*(namespace\s+[^\{]+){~m', $src, -1, PREG_SPLIT_DELIM_CAPTURE|PREG_SPLIT_NO_EMPTY);

  for($i=0;$i<count($chunks);)
  {
    $chunk = $chunks[$i];
    if(strpos(ltrim($chunk), 'namespace ') === 0)
    {
      $ns = trim(substr(ltrim($chunk), 9));
      $body = $chunks[$i+1];
      $nss[$ns] = $body;
      $i+=2;
    }
    else
      ++$i;
  }

  return $nss;
}