<?php
namespace taskman;
use Exception;

class ConfigParseResult
{
  public int $error = 0;
  public string $error_descr;
  public string $normalized_jzon = '';
  public array $parsed_arr;
  public int $parser_type;
  public $jsm_module;
}

function config_parse(array $base_dirs, string $file) : ConfigParseResult
{
  $res = new ConfigParseResult();

  $normalized_jzon = '';
  try
  {
    $jsm = new \JSM($base_dirs, $file);
    list($normalized_jzon, $jsm_module) = $jsm->process();
    $res->normalized_jzon = $normalized_jzon;
    $res->jsm_module = $jsm_module;
  }
  catch(Exception $e)
  {
    $res->error = 1;
    $res->error_descr = $e->getMessage() . "\n" . $e->getTraceAsString(); 
    return $res;
  }

  $decode_res = config_check_and_decode_jzon($normalized_jzon);
  
  if($decode_res[0] === 0)
  {
    $res->parsed_arr = $decode_res[2];
    $res->parser_type = $decode_res[3];
  }
  else
  {
    $res->error = $decode_res[0];
    $res->error_descr = $decode_res[1];
  }

  return $res;
}

function config_check_and_decode_jzon(string $json) : array
{
  try
  {
    $parser = 0;
    $arr = \jzon_parse($json, $parser);
    return array(0, "", $arr, $parser);
  }
  catch(Exception $e)
  {
    return array(1, $e->getMessage(), array(), 0);
  }
}

function config_get_header(string $file, ?int &$conf_id, ?string &$strid, bool $use_cache = true) : bool
{
  static $cache = array();
  if($use_cache && isset($cache[$file]))
  {
    list($conf_id, $strid) = $cache[$file];
    return true;
  }

  $h = fopen($file, "r");
  $line = fgets($h, 256);
  fclose($h);

  //TODO: rewrite it without regex usage
  if(preg_match('~\{\s*/\*\s*proto_id\s*=\s*(\d+)\s*;\s*alias\s*=\s*([^\s]+)~', $line, $matches))
  {
    $conf_id = (int)$matches[1];
    $strid = $matches[2];
    if($use_cache)
      $cache[$file] = array($conf_id, $strid);
    return true;
  }
  else
    return false;
}

function config_set_header(string $contents, int $conf_id, string $strid, bool &$is_success) : string
{
  $contents = preg_replace('~\s*\{~', "{  /* proto_id = {$conf_id} ; alias = {$strid} */", $contents, 1/*limit*/, $count);
  $is_success = $count == 1;
  return $contents;
}

function config_replace_header(string $contents) : string
{
  return preg_replace('~(\s*\{)\s*/\*\s*proto_id\s*=\s*\d+\s*;\s*alias\s*=\s*[^\s]+\s*\*/~', '$1', $contents);
}

//returns [proto_id, alias]
function config_ensure_header(string $conf_dir, string $file, bool $force = false) : array
{
  if(config_get_header($file, $curr_proto_id, $curr_alias, !$force))
  {
    //TODO: add 'normalized' argument when we are sure both path arguments are normalized
    $alias = config_file2strid($conf_dir, $file);
    if($force)
      $curr_proto_id = config_file2id($conf_dir, $file);

    //NOTE: keeping current proto id intact if not forced
    if($force || $curr_alias !== $alias)
    {
      $lines = file($file);
      //TODO: why not using config_set_header(..) ?
      $lines[0] = preg_replace(
        '~\s*\{\s*/\*\s*proto_id\s*=\s*\d+\s*;\s*alias\s*=\s*[^\s]+\s*\*/~', "{  /* proto_id = {$curr_proto_id} ; alias = {$alias} */", 
        $lines[0], 
        1/*limit*/, 
        $count);
      if($count != 1)
        throw new Exception("Could not set header for '$file' in line: {$lines[0]}");
      ensure_write_if_differs($file, join("", $lines));
    }

    return array($curr_proto_id, $alias);
  }
  else
  {
    $conf_id = config_file2id($conf_dir, $file);
    $alias = config_file2strid($conf_dir, $file);

    $lines = file($file);

    $is_success = false;
    $lines[0] = config_set_header($lines[0], $conf_id, $alias, $is_success);
    if(!$is_success)
      throw new Exception("Could not set header for '$file' in line: {$lines[0]}");
    ensure_write($file, join("", $lines));

    return array($conf_id, $alias);
  }
}

function config_apply_class_normalization(array $kv_data, bool $check_junk = false) : array
{
  $class = $kv_data['class'];
  $norm_data = array();
  unset($kv_data['class']);
  call_user_func_array([$class, 'normalize'], 
    array(&$kv_data, &$norm_data, true, $check_junk));
  return array($class, $class::CLASS_ID, $norm_data);
}

//returns array<ref, number>
function config_content_match_refs(string $src) : array
{
  $refs = array();

  if(strpos($src, '@') === false)
    return $refs;

  if(preg_match_all('~"(@[^"]+)"~', $src, $matches))
  {
    foreach($matches[1] as $ref)
    {
      if(!isset($refs[$ref]))
        $refs[$ref] = 1;
      ++$refs[$ref];
    }
  }
  return $refs;
}