#ifndef _FDMPROTO_H_
#define _FDMPROTO_H_

/*
 * There are two ways to directly support Freedom¿ and both methods
 * interpret calls to the fs_iinpath memory area by fsel_[ex]input and 
 * additionally pass a structure to the path.
 * This procedure is simple to imagine: Reserve 128 bytes for the path 
 * now it's 128+sizeof(Fdm_Str).
 * In this memory (you don't have to concern yourself with global
 * legibility under MiNT) the following structure will be copied,
 * directly after the path string. The path will also be moved after
 * the sizeof(Fdm_Str). You can now follow two different paths:
 *
 * 1) Simply pass a pointer to this memory area in fs_iinpath.
 * Through the Magic at the start Freedom¿ immediately recognises the 
 * caller supports the protocol. This method has the disadvantage that
 * in the unlikely case that Freedom¿ isn't installed you can't use
 * it! You must also check in the Cookie jar to see if a FSEL-Cookie 
 * >= v2.0 is available (refer to SLECTRIC.H)
 *
 * 2) Pass a pointer to the path behind the structure. This is
 * understood by other file selectors so you don't need to check the
 * Cookie to see if Freedom¿ is installed. Freedom¿ can now simply 
 * check sizeof(Fdm_Str), from the pointer passed, to see if the Magic 
 * is present by chance, so long as MiNT with active memory protection
 * isn't active. Using this method Freedom¿ can still reply that it's 
 * harmless to access memory before the path:
 * If Freedom¿ finds the four characters '?Fdm' after the null byte of
 * the path (the same Magic as the structure expected), then it looks 
 * at the following path to find the structure. And now (finally),
 * the structure:
 */
typedef struct
{
	long magic;   /* '?Fdm' */
	int id;       /* any Id */
	int maxsel;   /* maximum number of selected files */
	struct
	{
        unsigned fullpaths : 1; /* full pathnames in the reply */
        unsigned doquote   : 1; /* Freedom¿ may quote */
        unsigned noname    : 1; /* no application names before title */
        unsigned sysmodal  : 1; /* System modal open */
        unsigned resvd     : 28; /* reserved (set to 0) */

	} flags;
	int handle;  /* After success contains the file selector's window 
	                handle (or 0 if a flying dialog).
	                Use: the calling program can then control the file 
                        selector, perhaps it sends Freedom¿ a WM_CLOSED 
                        message, or adds it to its stack of windows for 
                        window-cycling.
	              */
    int server;  /* After success contains the application ID of the file 
                        selector server. From it messages could also be 
                        sent at the same time to the window's handle.
	              */
	char path[0]; /* The old file selector path starts here... */

} Fdm_Str;

If fsel_input returns 'magic' then '!Fdm' is returned otherwise the call 
is forwarded to the OS, and the returned values (fs_iinpath, fs_iinsel, 
fs_iexbutton) are valid!

If the call is successful an AES message is passed to the application. 
Whether the application continues to run or waits in a sub-event loop for 
the reply (in which case you process only WM_REDRAW and Co) is entirely up 
to you although naturally it's better to continue running whenever 
possible.

The format of the AES reply message is:

#define FILE_SELECTED	0x4560
/* FILE_SELECTED: A file selector was closed:
 * Word 3:   ID of the file selectors (as given by fsel_[ex]input)
 * Word 4/5: Pointer to the path and extension at the time of closing
 * Word 6/7: Pointer to the selected files, or NULL, if the user has 
 *           cancelled the operation
 *           The files are separated using spaces and use single quotes to 
 *           preserve spaces inside filenames, for example:
 *           'Chrisker''s paperweight'
 */
#ifndef FILE_SELECTED
#define FILE_SELECTED		0x4560
#endif
/*
 * On receipt of this message the program can, for the following ten
 * seconds, safely access the (MiNT-global) memory, at the words 3/4
 * ie 6/7, and copy the data. Afterwards Freedom¿ releases the memory
 * again to GEMDOS (Mfree)!
 *
 *
 * Should a message be sent to the Server the following messages 
 * should be used instead of the standard screen manager messages
 * WM_TOPPED and WM_CLOSED. Normal messages passed may well be
 * unexpected. For instance the file selector may be ICFS Iconified if 
 * a [Shift] key is held down (WM_CLOSED), or the object under the 
 * mouse is served instead because Freedom¿ simulates background 
 * operation (WM_TOPPED) under SingleTOS.
 */ 
#ifndef WIN_TOPPED
#define WIN_TOPPED				0x7a22
#endif
#ifndef WIN_CLOSED
#define WIN_CLOSED				0x7a23
#endif

#endif /* _FDMPROTO_H_ */