/*
 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */
#include "precompiled.hpp"
#include "logging/logTagLevelExpression.hpp"
#include "logging/logTagSet.hpp"
#include "runtime/arguments.hpp"
#include "runtime/os.inline.hpp"

const char* LogTagLevelExpression::DefaultExpressionString = "all";

LogTagLevelExpression::~LogTagLevelExpression() {
  os::free(_string);
}

void LogTagLevelExpression::clear() {
  _ntags = 0;
  _ncombinations = 0;
  for (size_t combination = 0; combination < MaxCombinations; combination++) {
    _level[combination] = LogLevel::Invalid;
    _allow_other_tags[combination] = false;
    for (size_t tag = 0; tag < LogTag::MaxTags; tag++) {
      _tags[combination][tag] = LogTag::__NO_TAG;
    }
  }
  os::free(_string);
  _string = NULL;
}

bool LogTagLevelExpression::parse(const char* str, outputStream* errstream) {
  bool success = true;
  clear();
  if (str == NULL || strcmp(str, "") == 0) {
    str = DefaultExpressionString;
  }
  char* copy = os::strdup_check_oom(str, mtLogging);
  // Split string on commas
  for (char *comma_pos = copy, *cur = copy; success && comma_pos != NULL; cur = comma_pos + 1) {
    if (_ncombinations == MaxCombinations) {
      if (errstream != NULL) {
        errstream->print_cr("Can not have more than " SIZE_FORMAT " tag combinations in a what-expression.",
                            MaxCombinations);
      }
      success = false;
      break;
    }

    comma_pos = strchr(cur, ',');
    if (comma_pos != NULL) {
      *comma_pos = '\0';
    }

    // Parse the level, if specified
    LogLevelType level = LogLevel::Unspecified;
    char* equals = strchr(cur, '=');
    if (equals != NULL) {
      level = LogLevel::from_string(equals + 1);
      if (level == LogLevel::Invalid) {
        if (errstream != NULL) {
          errstream->print_cr("Invalid level '%s' in what-expression.", equals + 1);
        }
        success = false;
        break;
      }
      *equals = '\0'; // now ignore "=level" part of substr
    }
    set_level(level);

    // Parse special tags such as 'all'
    if (strcmp(cur, "all") == 0) {
      set_allow_other_tags();
      new_combination();
      continue;
    }

    // Check for '*' suffix
    char* asterisk_pos = strchr(cur, '*');
    if (asterisk_pos != NULL && asterisk_pos[1] == '\0') {
      set_allow_other_tags();
      *asterisk_pos = '\0';
    }

    // Parse the tag expression (t1+t2+...+tn)
    char* plus_pos;
    char* cur_tag = cur;
    do {
      plus_pos = strchr(cur_tag, '+');
      if (plus_pos != NULL) {
        *plus_pos = '\0';
      }
      LogTagType tag = LogTag::from_string(cur_tag);
      if (tag == LogTag::__NO_TAG) {
        if (errstream != NULL) {
          errstream->print_cr("Invalid tag '%s' in what-expression.", cur_tag);
        }
        success = false;
        break;
      }
      if (_ntags == LogTag::MaxTags) {
        if (errstream != NULL) {
          errstream->print_cr("Tag combination exceeds the maximum of " SIZE_FORMAT " tags.",
                              LogTag::MaxTags);
        }
        success = false;
        break;
      }
      add_tag(tag);
      cur_tag = plus_pos + 1;
    } while (plus_pos != NULL);

    new_combination();
  }

  // Save the (unmodified) string for printing purposes.
  _string = copy;
  strcpy(_string, str);

  return success;
}

LogLevelType LogTagLevelExpression::level_for(const LogTagSet& ts) const {
  LogLevelType level = LogLevel::Off;
  for (size_t combination = 0; combination < _ncombinations; combination++) {
    bool contains_all = true;
    size_t tag_idx;
    for (tag_idx = 0; tag_idx < LogTag::MaxTags && _tags[combination][tag_idx] != LogTag::__NO_TAG; tag_idx++) {
      if (!ts.contains(_tags[combination][tag_idx])) {
        contains_all = false;
        break;
      }
    }
    // All tags in the expression must be part of the tagset,
    // and either the expression allows other tags (has a wildcard),
    // or the number of tags in the expression and tagset must match.
    if (contains_all && (_allow_other_tags[combination] || tag_idx == ts.ntags())) {
      level = _level[combination];
    }
  }
  return level;
}