/*
* File:        SearchPath.cpp
*
* Copyright (c) Freescale Semiconductor, Inc. All rights reserved.
* See included license file for license details.
*/

#include "SearchPath.h"
#include <stdio.h>

#if defined(WIN32)
       #define PATH_SEP_CHAR '\\'
       #define PATH_SEP_STRING "\\"
#else
       #define PATH_SEP_CHAR '/'
       #define PATH_SEP_STRING "/"
#endif

PathSearcher * PathSearcher::s_searcher = NULL;

//! This function will create the global path search object if it has
//! not already been created.
PathSearcher & PathSearcher::getGlobalSearcher()
{
       if (!s_searcher)
       {
               s_searcher = new PathSearcher;
       }

       return *s_searcher;
}

void PathSearcher::addSearchPath(std::string & path)
{
       m_paths.push_back(path);
}

//! The \a base path argument can be either a relative or absolute path. If the path
//! is relative, then it is joined with search paths one after another until a matching
//! file is located or all search paths are exhausted. If the \a base is absolute,
//! only that path is tested and if invalid false is returned.
//!
//! \param base A path to the file that is to be found.
//! \param targetType Currently ignored. In the future it will let you select whether to
//!             find a file or directory.
//! \param searchCwd If set to true, the current working directory is searched before using
//!             any of the search paths. Otherwise only the search paths are considered.
//! \param[out] result When true is returned this string is set to the first path at which
//!             a valid file was found.
//!
//! \retval true A matching file was found among the search paths. The contents of \a result
//!             are a valid path.
//! \retval false No match could be made. \a result has been left unmodified.
bool PathSearcher::search(const std::string & base, target_type_t targetType, bool searchCwd, std::string & result)
{
       FILE * tempFile;
       bool absolute = isAbsolute(base);

       // Try cwd first if requested. Same process applies to absolute paths.
       if (absolute || searchCwd)
       {
               tempFile = fopen(base.c_str(), "r");
               if (tempFile)
               {
                       fclose(tempFile);
                       result = base;
                       return true;
               }
       }

       // If the base path is absolute and the previous test failed, then we don't go any further.
       if (absolute)
       {
               return false;
       }

       // Iterate over all search paths.
       string_list_t::const_iterator it = m_paths.begin();
       for (; it != m_paths.end(); ++it)
       {
               std::string searchPath = joinPaths(*it, base);

               tempFile = fopen(searchPath.c_str(), "r");
               if (tempFile)
               {
                       fclose(tempFile);
                       result = searchPath;
                       return true;
               }
       }

       // Couldn't find anything matching the base path.
       return false;
}

bool PathSearcher::isAbsolute(const std::string & path)
{
#if __WIN32__
       return path.size() >= 3 && path[1] == ':' && path[2] == '\\';
#else
       return path.size() >= 1 && path[0] == '/';
#endif
}

std::string PathSearcher::joinPaths(const std::string & first, const std::string & second)
{
       // Start with first string.
       std::string result = first;

       // Add path separator if needed
       if ((first[first.size() - 1] != PATH_SEP_CHAR) && (second[0] != PATH_SEP_CHAR))
       {
               result += PATH_SEP_STRING;
       }

       // Append the second string.
       result += second;

       // And return the whole mess.
       return result;
}