/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying

   file LICENSE.rst or https://cmake.org/licensing for details.  */

#include "cmXMLParser.h"

#include <cstring>

#include <iostream>

#include <sstream>

#include <cm3p/expat.h>

#include "cmsys/FStream.hxx"

cmXMLParser::cmXMLParser()

{

  this->Parser = nullptr;

  this->ParseError = 0;

  this->ReportCallback = nullptr;

  this->ReportCallbackData = nullptr;

}

cmXMLParser::~cmXMLParser()

{

  if (this->Parser) {

    this->CleanupParser();

  }

}

int cmXMLParser::Parse(char const* string)

{

  return this->InitializeParser() &&

    this->ParseChunk(string, strlen(string)) && this->CleanupParser();

}

int cmXMLParser::ParseFile(char const* file)

{

  if (!file) {

    return 0;

  }

  cmsys::ifstream ifs(file);

  if (!ifs) {

    return 0;

  }

  std::ostringstream str;

  str << ifs.rdbuf();

  return this->Parse(str.str().c_str());

}

int cmXMLParser::InitializeParser()

{

  if (this->Parser) {

    std::cerr << "Parser already initialized" << std::endl;

    this->ParseError = 1;

    return 0;

  }

  // Create the expat XML parser.

  this->Parser = XML_ParserCreate(nullptr);

  XML_SetElementHandler(static_cast<XML_Parser>(this->Parser),

                        &cmXMLParserStartElement, &cmXMLParserEndElement);

  XML_SetCharacterDataHandler(static_cast<XML_Parser>(this->Parser),

                              &cmXMLParserCharacterDataHandler);

  XML_SetUserData(static_cast<XML_Parser>(this->Parser), this);

  this->ParseError = 0;

  return 1;

}

int cmXMLParser::ParseChunk(char const* inputString,

                            std::string::size_type length)

{

  if (!this->Parser) {

    std::cerr << "Parser not initialized" << std::endl;

    this->ParseError = 1;

    return 0;

  }

  int res;

  res = this->ParseBuffer(inputString, length);

  if (res == 0) {

    this->ParseError = 1;

  }

  return res;

}

int cmXMLParser::CleanupParser()

{

  if (!this->Parser) {

    std::cerr << "Parser not initialized" << std::endl;

    this->ParseError = 1;

    return 0;

  }

  int result = !this->ParseError;

  if (result) {

    // Tell the expat XML parser about the end-of-input.

    if (!XML_Parse(static_cast<XML_Parser>(this->Parser), "", 0, 1)) {

      this->ReportXmlParseError();

      result = 0;

    }

  }

  // Clean up the parser.

  XML_ParserFree(static_cast<XML_Parser>(this->Parser));

  this->Parser = nullptr;

  return result;

}

int cmXMLParser::ParseBuffer(char const* buffer, std::string::size_type count)

{

  // Pass the buffer to the expat XML parser.

  if (!XML_Parse(static_cast<XML_Parser>(this->Parser), buffer,

                 static_cast<int>(count), 0)) {

    this->ReportXmlParseError();

    return 0;

  }

  return 1;

}

int cmXMLParser::ParseBuffer(char const* buffer)

{

  return this->ParseBuffer(buffer, static_cast<int>(strlen(buffer)));

}

int cmXMLParser::ParsingComplete()

{

  // Default behavior is to parse to end of stream.

  return 0;

}

void cmXMLParser::StartElement(std::string const& name, char const** /*atts*/)

{

  std::cout << "Start element: " << name << std::endl;

}

void cmXMLParser::EndElement(std::string const& name)

{

  std::cout << "End element: " << name << std::endl;

}

void cmXMLParser::CharacterDataHandler(char const* /*inData*/,

                                       int /*inLength*/)

{

}

char const* cmXMLParser::FindAttribute(char const** atts,

                                       char const* attribute)

{

  if (atts && attribute) {

    for (char const** a = atts; *a && *(a + 1); a += 2) {

      if (strcmp(*a, attribute) == 0) {

        return *(a + 1);

      }

    }

  }

  return nullptr;

}

void cmXMLParserStartElement(void* parser, char const* name, char const** atts)

{

  // Begin element handler that is registered with the XML_Parser.

  // This just casts the user data to a cmXMLParser and calls

  // StartElement.

  static_cast<cmXMLParser*>(parser)->StartElement(name, atts);

}

void cmXMLParserEndElement(void* parser, char const* name)

{

  // End element handler that is registered with the XML_Parser.  This

  // just casts the user data to a cmXMLParser and calls EndElement.

  static_cast<cmXMLParser*>(parser)->EndElement(name);

}

void cmXMLParserCharacterDataHandler(void* parser, char const* data,

                                     int length)

{

  // Character data handler that is registered with the XML_Parser.

  // This just casts the user data to a cmXMLParser and calls

  // CharacterDataHandler.

  static_cast<cmXMLParser*>(parser)->CharacterDataHandler(data, length);

}

void cmXMLParser::ReportXmlParseError()

{

  XML_Parser parser = static_cast<XML_Parser>(this->Parser);

  this->ReportError(static_cast<int>(XML_GetCurrentLineNumber(parser)),

                    static_cast<int>(XML_GetCurrentColumnNumber(parser)),

                    XML_ErrorString(XML_GetErrorCode(parser)));

}

void cmXMLParser::ReportError(int line, int /*unused*/, char const* msg)

{

  if (this->ReportCallback) {

    this->ReportCallback(line, msg, this->ReportCallbackData);

  } else {

    std::cerr << "Error parsing XML in stream at line " << line << ": " << msg

              << std::endl;

  }

}