/*
 * Copyright 1993, 1995 Christopher Seiwald.
 *
 * This file is part of Jam - see jam.c for Copyright information.
 */

/* This file is ALSO:
 * Copyright 2001-2004 David Abrahams.
 * Copyright 2005 Rene Rivera.
 * Distributed under the Boost Software License, Version 1.0.
 * (See accompanying file LICENSE_1_0.txt or copy at
 * http://www.boost.org/LICENSE_1_0.txt)
 */

/*
 * filent.c - scan directories and archives on NT
 *
 * External routines:
 *  file_mkdir()                    - create a directory
 *  file_supported_fmt_resolution() - file modification timestamp resolution
 *
 * External routines called only via routines in filesys.c:
 *  file_collect_dir_content_() - collects directory content information
 *  file_dirscan_()             - OS specific file_dirscan() implementation
 *  file_query_()               - query information about a path from the OS
 */

#include "jam.h"
#ifdef OS_NT
#include "filesys.h"

#include "object.h"
#include "pathsys.h"
#include "strings.h"

#ifdef __BORLANDC__
# undef FILENAME  /* cpp namespace collision */
#endif

#define WIN32_LEAN_AND_MEAN
#include <windows.h>

#include <assert.h>
#include <ctype.h>
#include <direct.h>
#include <io.h>


/*
 * file_collect_dir_content_() - collects directory content information
 */

int file_collect_dir_content_( file_info_t * const d )
{
    PATHNAME f;
    string pathspec[ 1 ];
    string pathname[ 1 ];
    LIST * files = L0;
    int d_length;

    assert( d );
    assert( d->is_dir );
    assert( list_empty( d->files ) );

    d_length = strlen( object_str( d->name ) );

    memset( (char *)&f, '\0', sizeof( f ) );
    f.f_dir.ptr = object_str( d->name );
    f.f_dir.len = d_length;

    /* Prepare file search specification for the FindXXX() Windows API. */
    if ( !d_length )
        string_copy( pathspec, ".\\*" );
    else
    {
        /* We can not simply assume the given folder name will never include its
         * trailing path separator or otherwise we would not support the Windows
         * root folder specified without its drive letter, i.e. '\'.
         */
        char const trailingChar = object_str( d->name )[ d_length - 1 ] ;
        string_copy( pathspec, object_str( d->name ) );
        if ( ( trailingChar != '\\' ) && ( trailingChar != '/' ) )
            string_append( pathspec, "\\" );
        string_append( pathspec, "*" );
    }

    /* The following code for collecting information about all files in a folder
     * needs to be kept synchronized with how the file_query() operation is
     * implemented (collects information about a single file).
     */
    {
        /* FIXME: Avoid duplicate FindXXX Windows API calls here and in the code
         * determining a normalized path.
         */
        WIN32_FIND_DATA finfo;
        HANDLE const findHandle = FindFirstFileA( pathspec->value, &finfo );
        if ( findHandle == INVALID_HANDLE_VALUE )
        {
            string_free( pathspec );
            return -1;
        }

        string_new( pathname );
        do
        {
            OBJECT * pathname_obj;

            f.f_base.ptr = finfo.cFileName;
            f.f_base.len = strlen( finfo.cFileName );

            string_truncate( pathname, 0 );
            path_build( &f, pathname );

            pathname_obj = object_new( pathname->value );
            path_register_key( pathname_obj );
            files = list_push_back( files, pathname_obj );
            {
                int found;
                file_info_t * const ff = file_info( pathname_obj, &found );
                ff->is_dir = finfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
                ff->is_file = !ff->is_dir;
                ff->exists = 1;
                timestamp_from_filetime( &ff->time, &finfo.ftLastWriteTime );
            }
        }
        while ( FindNextFile( findHandle, &finfo ) );

        FindClose( findHandle );
    }

    string_free( pathname );
    string_free( pathspec );

    d->files = files;
    return 0;
}


/*
 * file_dirscan_() - OS specific file_dirscan() implementation
 */

void file_dirscan_( file_info_t * const d, scanback func, void * closure )
{
    assert( d );
    assert( d->is_dir );

    /* Special case \ or d:\ : enter it */
    {
        char const * const name = object_str( d->name );
        if ( name[ 0 ] == '\\' && !name[ 1 ] )
        {
            (*func)( closure, d->name, 1 /* stat()'ed */, &d->time );
        }
        else if ( name[ 0 ] && name[ 1 ] == ':' && name[ 2 ] && !name[ 3 ] )
        {
            /* We have just entered a 3-letter drive name spelling (with a
             * trailing slash), into the hash table. Now enter its two-letter
             * variant, without the trailing slash, so that if we try to check
             * whether "c:" exists, we hit it.
             *
             * Jam core has workarounds for that. Given:
             *    x = c:\whatever\foo ;
             *    p = $(x:D) ;
             *    p2 = $(p:D) ;
             * There will be no trailing slash in $(p), but there will be one in
             * $(p2). But, that seems rather fragile.
             */
            OBJECT * const dir_no_slash = object_new_range( name, 2 );
            (*func)( closure, d->name, 1 /* stat()'ed */, &d->time );
            (*func)( closure, dir_no_slash, 1 /* stat()'ed */, &d->time );
            object_free( dir_no_slash );
        }
    }
}


/*
 * file_mkdir() - create a directory
 */

int file_mkdir( char const * const path )
{
    return _mkdir( path );
}


/*
 * file_query_() - query information about a path from the OS
 *
 * The following code for collecting information about a single file needs to be
 * kept synchronized with how the file_collect_dir_content_() operation is
 * implemented (collects information about all files in a folder).
 */

int try_file_query_root( file_info_t * const info )
{
    WIN32_FILE_ATTRIBUTE_DATA fileData;
    char buf[ 4 ];
    char const * const pathstr = object_str( info->name );
    if ( !pathstr[ 0 ] )
    {
        buf[ 0 ] = '.';
        buf[ 1 ] = 0;
    }
    else if ( pathstr[ 0 ] == '\\' && ! pathstr[ 1 ] )
    {
        buf[ 0 ] = '\\';
        buf[ 1 ] = '\0';
    }
    else if ( pathstr[ 1 ] == ':' )
    {
        if ( !pathstr[ 2 ] )
        {
        }
        else if ( !pathstr[ 2 ] || ( pathstr[ 2 ] == '\\' && !pathstr[ 3 ] ) )
        {
            buf[ 0 ] = pathstr[ 0 ];
            buf[ 1 ] = ':';
            buf[ 2 ] = '\\';
            buf[ 3 ] = '\0';
        }
        else
        {
            return 0;
        }
    }
    else
    {
        return 0;
    }
        
    /* We have a root path */
    if ( !GetFileAttributesExA( buf, GetFileExInfoStandard, &fileData ) )
    {
        info->is_dir = 0;
        info->is_file = 0;
        info->exists = 0;
        timestamp_clear( &info->time );
    }
    else
    {
        info->is_dir = fileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
        info->is_file = !info->is_dir;
        info->exists = 1;
        timestamp_from_filetime( &info->time, &fileData.ftLastWriteTime );
    }
    return 1;
}

void file_query_( file_info_t * const info )
{
    char const * const pathstr = object_str( info->name );
    const char * dir;
    OBJECT * parent;
    file_info_t * parent_info;

    if ( try_file_query_root( info ) )
        return;

    if ( ( dir = strrchr( pathstr, '\\' ) ) )
    {
        parent = object_new_range( pathstr, dir - pathstr );
    }
    else
    {
        parent = object_copy( constant_empty );
    }
    parent_info = file_query( parent );
    object_free( parent );
    if ( !parent_info || !parent_info->is_dir )
    {
        info->is_dir = 0;
        info->is_file = 0;
        info->exists = 0;
        timestamp_clear( &info->time );
    }
    else
    {
        info->is_dir = 0;
        info->is_file = 0;
        info->exists = 0;
        timestamp_clear( &info->time );
        if ( list_empty( parent_info->files ) )
            file_collect_dir_content_( parent_info );
    }
}


/*
 * file_supported_fmt_resolution() - file modification timestamp resolution
 *
 * Returns the minimum file modification timestamp resolution supported by this
 * Boost Jam implementation. File modification timestamp changes of less than
 * the returned value might not be recognized.
 *
 * Does not take into consideration any OS or file system related restrictions.
 *
 * Return value 0 indicates that any value supported by the OS is also supported
 * here.
 */

void file_supported_fmt_resolution( timestamp * const t )
{
    /* On Windows we support nano-second file modification timestamp resolution,
     * just the same as the Windows OS itself.
     */
    timestamp_init( t, 0, 0 );
}

#endif  /* OS_NT */