/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#ifndef T_CONST_VALUE_H
#define T_CONST_VALUE_H

#include "thrift/parse/t_enum.h"
#include <stdint.h>
#include <map>
#include <vector>
#include <string>

/**
 * A const value is something parsed that could be a map, set, list, struct
 * or whatever.
 *
 */
class t_const_value {
public:
  /**
   * Comparator to sort fields in ascending order by key.
   * Make this a functor instead of a function to help GCC inline it.
   */
  struct value_compare {
  public:
    bool operator()(t_const_value const* const& left, t_const_value const* const& right) const {
      return *left < *right;
    }
  };

  enum t_const_value_type { CV_INTEGER, CV_DOUBLE, CV_STRING, CV_MAP, CV_LIST, CV_IDENTIFIER, CV_UNKNOWN };

  t_const_value() : intVal_(0), doubleVal_(0.0f), enum_((t_enum*)nullptr), valType_(CV_UNKNOWN) {}

  t_const_value(int64_t val) : doubleVal_(0.0f), enum_((t_enum*)nullptr), valType_(CV_UNKNOWN) { set_integer(val); }

  t_const_value(std::string val) : intVal_(0), doubleVal_(0.0f), enum_((t_enum*)nullptr), valType_(CV_UNKNOWN) { set_string(val); }

  void set_string(std::string val) {
    valType_ = CV_STRING;
    stringVal_ = val;
  }

  std::string get_string() const { return stringVal_; }

  void set_integer(int64_t val) {
    valType_ = CV_INTEGER;
    intVal_ = val;
  }

  int64_t get_integer() const {
    if (valType_ == CV_IDENTIFIER) {
      if (enum_ == nullptr) {
        throw "have identifier \"" + get_identifier() + "\", but unset enum on line!";
      }
      std::string identifier = get_identifier();
      std::string::size_type dot = identifier.rfind('.');
      if (dot != std::string::npos) {
        identifier = identifier.substr(dot + 1);
      }
      t_enum_value* val = enum_->get_constant_by_name(identifier);
      if (val == nullptr) {
        throw "Unable to find enum value \"" + identifier + "\" in enum \"" + enum_->get_name()
            + "\"";
      }
      return val->get_value();
    } else {
      return intVal_;
    }
  }

  void set_uuid(std::string val) {
    validate_uuid(val);
    valType_ = CV_STRING;
    stringVal_ = val;
  }

  std::string get_uuid() const {
    std::string tmp = stringVal_;
    validate_uuid(tmp);
    return tmp;
  }

  void set_double(double val) {
    valType_ = CV_DOUBLE;
    doubleVal_ = val;
  }

  double get_double() const { return doubleVal_; }

  void set_map() { valType_ = CV_MAP; }

  void add_map(t_const_value* key, t_const_value* val) { mapVal_[key] = val; }

  const std::map<t_const_value*, t_const_value*, t_const_value::value_compare>& get_map() const { return mapVal_; }

  void set_list() { valType_ = CV_LIST; }

  void add_list(t_const_value* val) { listVal_.push_back(val); }

  const std::vector<t_const_value*>& get_list() const { return listVal_; }

  void set_identifier(std::string val) {
    valType_ = CV_IDENTIFIER;
    identifierVal_ = val;
  }

  std::string get_identifier() const { return identifierVal_; }

  std::string get_identifier_name() const {
    std::string ret = get_identifier();
    size_t s = ret.find('.');
    if (s == std::string::npos) {
      throw "error: identifier " + ret + " is unqualified!";
    }
    ret = ret.substr(s + 1);
    s = ret.find('.');
    if (s != std::string::npos) {
      ret = ret.substr(s + 1);
    }
    return ret;
  }

  std::string get_identifier_with_parent() const {
    std::string ret = get_identifier();
    size_t s = ret.find('.');
    if (s == std::string::npos) {
      throw "error: identifier " + ret + " is unqualified!";
    }
    size_t s2 = ret.find('.', s + 1);
    if (s2 != std::string::npos) {
      ret = ret.substr(s + 1);
    }
    return ret;
  }

  void set_enum(t_enum* tenum) { enum_ = tenum; }

  t_const_value_type get_type() const { if (valType_ == CV_UNKNOWN) { throw std::string("unknown t_const_value"); } return valType_; }

  /**
   * Comparator to sort map fields in ascending order by key and then value.
   * This is used for map comparison in lexicographic order.
   */
  struct map_entry_compare {
  private:
    typedef std::pair<t_const_value*, t_const_value*> ConstPair;
  public:
    bool operator()(ConstPair left, ConstPair right) const {
      if (*(left.first) < *(right.first)) {
        return true;
      } else {
        if (*(right.first) < *(left.first)) {
          return false;
        } else {
          return *(left.second) < *(right.second);
        }
      }
    }
  };

  bool operator < (const t_const_value& that) const {
    ::t_const_value::t_const_value_type t1 = get_type();
    ::t_const_value::t_const_value_type t2 = that.get_type();
    if (t1 != t2)
      return t1 < t2;
    switch (t1) {
    case ::t_const_value::CV_INTEGER:
      return intVal_ < that.intVal_;
    case ::t_const_value::CV_DOUBLE:
      return doubleVal_ < that.doubleVal_;
    case ::t_const_value::CV_STRING:
      return stringVal_ < that.stringVal_;
    case ::t_const_value::CV_IDENTIFIER:
      return identifierVal_ < that.identifierVal_;
    case ::t_const_value::CV_MAP:
      return std::lexicographical_compare(
          mapVal_.begin(), mapVal_.end(), that.mapVal_.begin(), that.mapVal_.end(), map_entry_compare());
    case ::t_const_value::CV_LIST:
      return std::lexicographical_compare(
          listVal_.begin(), listVal_.end(), that.listVal_.begin(), that.listVal_.end(), value_compare());
    case ::t_const_value::CV_UNKNOWN:
    default:
      throw "unknown value type";
    }
  }

private:
  std::map<t_const_value*, t_const_value*, value_compare> mapVal_;
  std::vector<t_const_value*> listVal_;
  std::string stringVal_;
  int64_t intVal_;
  double doubleVal_;
  std::string identifierVal_;
  t_enum* enum_;

  t_const_value_type valType_;

  void validate_uuid(std::string & uuid) const {
    const std::string HEXCHARS = std::string("0123456789ABCDEFabcdef");

    // we also allow for usual "Windows GUID" format "{01234567-9012-4567-9012-456789012345}"
    if ((uuid.length() == 38) && ('{' == uuid[0]) && ('}' == uuid[37])) {
      uuid = uuid.substr(1, 36);
    }

    // canonical format "01234567-9012-4567-9012-456789012345" expected
    bool valid = (uuid.length() == 36);
    for (size_t i = 0; valid && (i < uuid.length()); ++i) {
      switch(i) {
        case 8:
        case 13:
        case 18:
        case 23:
          if(uuid[i] != '-') {
            valid = false;
          }
          break;
        default:
          if(HEXCHARS.find(uuid[i]) == std::string::npos) {
            valid = false;
          }
          break;
      }
    }

    if( ! valid) {
      throw "invalid uuid " + uuid;
    }
  }
};

#endif