; Project name	:	Assembly Library
; Description	:	Displays file dialog.

;
; XTIDE Universal BIOS and Associated Tools
; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2023 by XTIDE Universal BIOS Team.
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.
; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
;

CURRENTDIR_CHARACTERS	EQU		002Eh
UPDIR_CHARACTERS		EQU		2E2Eh

; Section containing code
SECTION .text

;--------------------------------------------------------------------
; DialogFile_GetFileNameWithIoInDSSI
;	Parameters:
;		DS:SI:	Ptr to FILE_DIALOG_IO
;		SS:BP:	Ptr to parent MENU
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX, BX, CX, DX, DI
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
DialogFile_GetFileNameWithIoInDSSI:
	; We need to store default drive because user might change drive but
	; then cancel the file selection. In that case the original default directory
	; must be restored.
	call	Drive_GetDefaultToAL
	push	ax

	mov		bx, FileEventHandler
	mov		BYTE [si+FILE_DIALOG_IO.bUserCancellation], TRUE
	call	Dialog_DisplayWithDialogInputInDSSIandHandlerInBX

	; Now restore the default drive if user cancellation
	pop		dx
	cmp		BYTE [si+FILE_DIALOG_IO.bUserCancellation], TRUE
	jne		SHORT .UserDidNotCancel
	jmp		Drive_SetDefaultFromDL

.UserDidNotCancel:
	ret


;--------------------------------------------------------------------
; FileEventHandler
;	Common parameters for all events:
;		BX:			Menu event (anything from MENUEVENT struct)
;		SS:BP:		Ptr to DIALOG
;	Common return values for all events:
;		CF:			Set if event processed
;					Cleared if event not processed
;	Corrupts registers:
;		All
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
FileEventHandler:
	jmp		[cs:bx+.rgfnEventHandlers]


ALIGN JUMP_ALIGN
.ItemSelectedFromCX:
	call	LoadItemStringBufferToESDI
	call	Registers_CopyESDItoDSSI
	call	ItemLineSplitter_GetLineToDSSIandLengthToCXfromStringInDSSIwithIndexInCX
	jmp		ParseSelectionFromItemLineInDSSI


ALIGN JUMP_ALIGN
.RefreshInformation:
	call	GetInfoLinesToCXandDialogFlagsToAX
	mov		si, [cs:.rgszInfoStringLookup]
	xor		bx, bx
	xchg	dx, ax
ALIGN JUMP_ALIGN
.InfoLineLoop:
	shr		dl, 1
	jnc		SHORT .CheckNextFlag
	mov		si, [cs:bx+.rgszInfoStringLookup]
	push	bx
	CALL_DISPLAY_LIBRARY PrintNullTerminatedStringFromCSSI
	pop		bx
ALIGN JUMP_ALIGN
.CheckNextFlag:
	inc		bx
	inc		bx
	loop	.InfoLineLoop
	stc						; Event processed
	ret


ALIGN JUMP_ALIGN
.RefreshItemFromCX:
	call	LoadItemStringBufferToESDI
	mov		ax, FILE_STRING_LENGTH
	xchg	ax, cx
	mul		cx
	add		di, ax
	mov		si, di
	mov		bx, es
	dec		cx				; Do not print LF at the end of file string
	CALL_DISPLAY_LIBRARY PrintCharBufferFromBXSIwithLengthInCX
	stc
	ret


ALIGN WORD_ALIGN
.rgszInfoStringLookup:
	dw		g_szChangeDrive
%ifndef EXCLUDE_FROM_XTIDECFG
	dw		g_szSelectDirectory
	dw		g_szCreateNew
%endif

.rgfnEventHandlers:
istruc MENUEVENT
	at	MENUEVENT.InitializeMenuinitFromDSSI,	dw	InitializeMenuinitFromSSBP
	at	MENUEVENT.ExitMenu,						dw	Dialog_EventExitMenu
	at	MENUEVENT.IdleProcessing,				dw	Dialog_EventNotHandled
	at	MENUEVENT.ItemHighlightedFromCX,		dw	Dialog_EventNotHandled
	at	MENUEVENT.ItemSelectedFromCX,			dw	.ItemSelectedFromCX
	at	MENUEVENT.KeyStrokeInAX,				dw	HandleFunctionKeyFromAH
	at	MENUEVENT.RefreshTitle,					dw	Dialog_EventRefreshTitle
	at	MENUEVENT.RefreshInformation,			dw	.RefreshInformation
	at	MENUEVENT.RefreshItemFromCX,			dw	.RefreshItemFromCX
iend


;--------------------------------------------------------------------
; ReInitializeMenuinitFromSSBP
; InitializeMenuinitFromSSBP
;	Parameters:
;		SS:BP:		Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
ReInitializeMenuinitFromSSBP:
	call	DisplayLoadingMessageInInformationArea
InitializeMenuinitFromSSBP:
	call	LoadItemStringBufferToESDI
	call	CreateStringFromCurrentDirectoryContentsToESDI
	call	LoadItemStringBufferToESDI
	call	SortDirectoryContentsStringFromESDIwithCountInCX
	xor		ax, ax
	mov		[es:di-1], al							; Terminate with NULL
	call	Registers_CopySSBPtoDSSI
	call	Dialog_EventInitializeMenuinitFromDSSIwithHighlightedItemInAX
	call	GetInfoLinesToCXandDialogFlagsToAX
	mov		[bp+MENUINIT.bInfoLines], cl
	CALL_DISPLAY_LIBRARY GetColumnsToALandRowsToAH
	mov		[bp+MENUINIT.bHeight], ah				; Always max height
	mov		WORD [bp+MENU.wFirstVisibleItem], 0
	ret


;--------------------------------------------------------------------
; LoadItemStringBufferToESDI
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		ES:DI:	Ptr to item string buffer
;	Corrupts registers:
;		Nothing
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
LoadItemStringBufferToESDI:
	les		di, [bp+DIALOG.fpDialogIO]
	les		di, [es:di+FILE_DIALOG_IO.fszItemBuffer]
	ret


;--------------------------------------------------------------------
; CreateStringFromCurrentDirectoryContentsToESDI
;	Parameters:
;		ES:DI:	Buffer where to create item string
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		CX:		Number of files or directories found
;	Corrupts registers:
;		AX, BX, DX, SI, DI, DS
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
CreateStringFromCurrentDirectoryContentsToESDI:
	mov		bx, di
	CALL_DISPLAY_LIBRARY PushDisplayContext
	mov		cx, -1
	CALL_DISPLAY_LIBRARY PrepareOffScreenBufferInESBXwithLengthInCX	; ES:DI now points to buffer

	lds		si, [bp+DIALOG.fpDialogIO]
	eMOVZX	cx, [si+FILE_DIALOG_IO.bFileAttributes]
	lds		si, [si+FILE_DIALOG_IO.fpFileFilterString]
	call	Directory_UpdateDTAForFirstMatchForDSSIwithAttributesInCX

	call	.ClearDLifInRootDirectory
	call	Directory_GetDiskTransferAreaAddressToDSSI
	xor		cx, cx			; Clear file/directory count
	call	.FindMatchingFilesAndPrintThemToOffScreenBuffer

	JMP_DISPLAY_LIBRARY PopDisplayContext

;--------------------------------------------------------------------
; .ClearDLifInRootDirectory
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;		ES:DI:	Ptr to destination string buffer
;	Returns:
;		DL:		Cleared if in root directory
;				Set if in any other directory
;	Corrupts registers:
;		AX, SI, DS
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.ClearDLifInRootDirectory:
	call	Registers_CopyESDItoDSSI
	call	Directory_WriteCurrentPathToDSSI
	mov		dl, [si]
	ret

;--------------------------------------------------------------------
; .FindMatchingFilesAndPrintThemToOffScreenBuffer
;	Parameters:
;		CX:		Initial directory count
;		DL:		Zero if root directory selected
;		DS:SI:	Ptr to DTA with first matching file
;	Returns:
;		CX:		Incremented by number of files/directories found
;	Corrupts registers:
;		AX, BX, DX, DI, DS
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.FindMatchingFilesAndPrintThemToOffScreenBuffer:
	call	AppendFileFromDTAinDSSItoOffScreenBuffer
	call	Directory_UpdateDTAForNextMatchUsingPreviousParameters
	jnc		SHORT .FindMatchingFilesAndPrintThemToOffScreenBuffer
	ret


;--------------------------------------------------------------------
; AppendFileFromDTAinDSSItoOffScreenBuffer
;	Parameters:
;		CX:		Files/directories found
;		DL:		Zero if root directory selected
;		DS:SI:	Ptr to DTA containing file information
;	Returns:
;		CX:		Incremented by number of files/directories found
;	Corrupts registers:
;		AX, BX
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
AppendFileFromDTAinDSSItoOffScreenBuffer:
	cmp		WORD [si+DTA.szFile], CURRENTDIR_CHARACTERS
	je		SHORT .Return					; We never want "."
	test	dl, dl
	jnz		SHORT .NotInRootDirectory
	cmp		WORD [si+DTA.szFile], UPDIR_CHARACTERS
	je		SHORT .Return					; No ".." when in root directory
.NotInRootDirectory:
	inc		cx								; Nothing filtered so increment files/directories

	push	bp
	push	si
	push	dx
	push	cx
	call	.FormatFileOrDirectoryToBufferFromDTAinDSSI
	pop		cx
	pop		dx
	pop		si
	pop		bp
.Return:
	ret

;--------------------------------------------------------------------
; .FormatFileOrDirectoryToBufferFromDTAinDSSI
;	Parameters:
;		DS:SI:	Ptr to DTA containing file information
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX, BX, CX, DX, SI, DI, BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.FormatFileOrDirectoryToBufferFromDTAinDSSI:
	mov		bp, sp
	lea		ax, [si+DTA.szFile]

	test	BYTE [si+DTA.bFileAttributes], FLG_FILEATTR_DIRECTORY
	jnz		SHORT .FormatDirectory
	; Fall to .FormatFile

;--------------------------------------------------------------------
; .FormatFile
;	Parameters:
;		BP:		SP before pushing formatting parameters
;		DS:AX:	Far pointer to file name
;		DS:SI:	Ptr to DTA containing file information
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX, BX, CX, DX, SI, DI
;--------------------------------------------------------------------
.FormatFile:
	xchg	si, ax
	call	String_ConvertDSSItoLowerCase
	xchg	ax, si

	; Push parameters for file name
	push	ax				; Push file name offset
	push	ds				; Push file name segment

	; Push parameters for file size
	mov		ax, [si+DTA.dwFileSize]
	mov		dx, [si+DTA.dwFileSize+2]
	xor		bx, bx
	xor		cx, cx
	call	Size_GetSizeToAXAndCharToDLfromBXDXAXwithMagnitudeInCX
	mov		cl, 'i'
	cmp		dl, ' '
	eCMOVE	cl, dl
	push	ax
	push	dx
	push	cx

	; Format to buffer
	mov		si, g_szFileFormat
	jmp		SHORT .FormatStringInCSSIandReturn

;--------------------------------------------------------------------
; .FormatDirectory
;	Parameters:
;		BP:		SP before pushing formatting parameters
;		DS:AX:	Far pointer to directory name
;		DS:SI:	Ptr to DTA containing file information
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX, SI, DI
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.FormatDirectory:
	push	ax				; Push directory name offset
	push	ds				; Push directory name segment
	mov		ax, g_szSub
	cmp		WORD [si+DTA.szFile], UPDIR_CHARACTERS
	eCMOVE	ax, g_szUp
	push	ax
	mov		si, g_szDirectoryFormat
ALIGN JUMP_ALIGN
.FormatStringInCSSIandReturn:
	JMP_DISPLAY_LIBRARY FormatNullTerminatedStringFromCSSI


;--------------------------------------------------------------------
; SortDirectoryContentsStringFromESDIwithCountInCX
;	Parameters:
;		CX:		Number of files and directories
;		ES:DI:	Buffer containing directory contents string
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		ES:DI:	Ptr to end of directory contents string
;	Corrupts registers:
;		AX, BX, CX, DX, SI, DS
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
SortDirectoryContentsStringFromESDIwithCountInCX:
	call	Registers_CopyESDItoDSSI

	; Add directory contents string length to DI
	mov		ax, FILE_STRING_LENGTH
	push	ax
	mul		cx
	add		di, ax

	mov		dx, cx
	pop		cx
	mov		bx, .FileStringComparator
	jmp		Sort_ItemsFromDSSIwithCountInDXsizeInCXandComparatorInBX

;--------------------------------------------------------------------
; .FileStringComparator
;	Parameters:
;		CX:		Item size in bytes
;		DS:SI:	Ptr to first item to compare
;		ES:DI:	Ptr to second item to compare
;	Returns:
;		FLAGS:	Signed comparison between first and second item
;	Corrupts registers:
;		Nothing
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.FileStringComparator:
	push	di
	push	si
	push	cx
	push	bx

	mov		bx, FILE_STRING_LENGTH-2			; Zero BH
	cmp		WORD [si], UPDIR_CHARACTERS
	je		SHORT .ForceValueFromDSSItoBeLess
	mov		bl, [si+bx]
	cmp		bl, [es:di+FILE_STRING_LENGTH-2]	; 'B' for files, 'R' for directories
	jne		SHORT .ForceValueFromDSSItoBeMoreOrLess
	repe cmpsb									; Two directories or two files

ALIGN JUMP_ALIGN
.ReturnFromComparison:
	pop		bx
	pop		cx
	pop		si
	pop		di
	ret
ALIGN JUMP_ALIGN
.ForceValueFromDSSItoBeMoreOrLess:
	ja		SHORT .ForceValueFromDSSItoBeLess	; Directory in SI, file in DI
	xchg	bl, bh
	; Fall to ForceValueFromDSSItoBeLess
ALIGN JUMP_ALIGN
.ForceValueFromDSSItoBeLess:
	cmp		bh, bl
	jmp		SHORT .ReturnFromComparison


;--------------------------------------------------------------------
; GetInfoLinesToCXandDialogFlagsToAX
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		AX:		Dialog flags
;		CX:		Number of info lines to be displayed
;	Corrupts registers:
;		SI, DS
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
GetInfoLinesToCXandDialogFlagsToAX:
	ePUSH_T	ax, Bit_GetSetCountToCXfromAX
	xor		ah, ah
	; Fall to GetDialogFlagsToAL

;--------------------------------------------------------------------
; GetDialogFlagsToAL
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		AL:		Dialog flags
;	Corrupts registers:
;		SI, DS
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
GetDialogFlagsToAL:
	lds		si, [bp+DIALOG.fpDialogIO]
	mov		al, [si+FILE_DIALOG_IO.bDialogFlags]
	ret


;--------------------------------------------------------------------
; ParseSelectionFromItemLineInDSSI
;	Parameters:
;		DS:SI:	Ptr to char buffer containing file or directory to be selected
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
ParseSelectionFromItemLineInDSSI:
	mov		ax, [si]
	cmp		ax, UPDIR_CHARACTERS
	je		SHORT .ChangeToUpdir
	call	Char_IsUpperCaseLetterInAL
	jc		SHORT .ParseAndChangeToSubdirInDSSI
	call	Char_IsDecimalDigitInAL
	jc		SHORT .ParseAndChangeToSubdirInDSSI	; Assume subdir and check for errors
	; Fall to .ParseAndSelectFileFromDSSI

;--------------------------------------------------------------------
; .ParseAndSelectFileFromDSSI
;	Parameters:
;		DS:SI:	NULL terminated string selected from dialog
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing (exits dialog)
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
.ParseAndSelectFileFromDSSI:
	les		di, [bp+DIALOG.fpDialogIO]
	add		di, BYTE FILE_DIALOG_IO.szFile
	mov		cx, FILENAME_BUFFER_SIZE-1
	call	Memory_CopyCXbytesFromDSSItoESDI
	xor		ax, ax
	stosb						; Terminate with NULL
	jmp		SHORT CloseFileDialogAfterSuccessfulSelection

;--------------------------------------------------------------------
; .ChangeToUpdir
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.ChangeToUpdir:
	push	cs
	pop		ds
	mov		si, g_szUpdir
	jmp		SHORT .ChangeDirectoryToDSSI

;--------------------------------------------------------------------
; .ParseAndChangeToSubdirInDSSI
;	Parameters:
;		DS:SI:	NULL terminated string selected from dialog
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.ParseAndChangeToSubdirInDSSI:
	mov		BYTE [si+12], NULL	; Terminate with NULL (unnecessary spaces do not matter)
.ChangeDirectoryToDSSI:
	call	Directory_ChangeToPathFromDSSI
	jc		SHORT .ParseAndSelectFileFromDSSI	; Must have been a file starting with number
	; Fall to RefreshFilesToDisplay

;--------------------------------------------------------------------
; RefreshFilesToDisplay
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
RefreshFilesToDisplay:
	call	ReInitializeMenuinitFromSSBP
	jmp		MenuInit_RefreshMenuWindow


;--------------------------------------------------------------------
; HandleFunctionKeyFromAH
;	Parameters:
;		AH:		Scancode for function key
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX, SI, DI, BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
HandleFunctionKeyFromAH:
	call	GetDialogFlagsToAL
%ifndef EXCLUDE_FROM_XTIDECFG
	cmp		ah, KEY_FILEDIALOG_NEW_FILE_OR_DIR
	je		SHORT HandleFunctionKeyForCreatingNewFileOrDirectory
	cmp		ah, KEY_FILEDIALOG_SELECT_DIRECTORY
	je		SHORT HandleFunctionKeyForSelectingDirectoryInsteadOfFile
%endif
	cmp		ah, KEY_FILEDIALOG_CHANGE_DRIVE
	je		SHORT HandleFunctionKeyForDriveChange
ReturnWithoutHandlingKeystroke:
	clc		; Event not processed
	ret


;--------------------------------------------------------------------
; HandleFunctionKeyForCreatingNewFileOrDirectory
;	Parameters:
;		AL:		File dialog flags
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Closes file dialog
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
%ifndef EXCLUDE_FROM_XTIDECFG
ALIGN JUMP_ALIGN
HandleFunctionKeyForCreatingNewFileOrDirectory:
	test	al, FLG_FILEDIALOG_NEW
	jz		SHORT ReturnWithoutHandlingKeystroke

	mov		cl, STRING_DIALOG_IO_size
	call	Memory_ReserveCLbytesFromStackToDSSI

;;;	InitializeStringDialogIoInDSSIforInputtingFileName
	call	InitializeNullStringsToDialogInputInDSSI
	mov		WORD [si+DIALOG_INPUT.fszTitle], g_szEnterNewFileOrDirectory
	mov		WORD [si+STRING_DIALOG_IO.fnCharFilter], NULL
	mov		WORD [si+STRING_DIALOG_IO.wBufferSize], FILENAME_BUFFER_SIZE
	les		ax, [bp+DIALOG.fpDialogIO]
	add		ax, BYTE FILE_DIALOG_IO.szFile
	mov		[si+STRING_DIALOG_IO.fpReturnBuffer], ax
	mov		[si+STRING_DIALOG_IO.fpReturnBuffer+2], es
;;;

	CALL_MENU_LIBRARY GetStringWithIoInDSSI
	mov		al, [si+STRING_DIALOG_IO.bUserCancellation]
	add		sp, BYTE STRING_DIALOG_IO_size
	test	al, al		; User cancellation?
	jnz		SHORT ReturnWithoutHandlingKeystroke
	jmp		CloseFileDialogAfterSuccessfulSelection


;--------------------------------------------------------------------
; HandleFunctionKeyForSelectingDirectoryInsteadOfFile
;	Parameters:
;		AL:		File dialog flags
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Closes file dialog
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
HandleFunctionKeyForSelectingDirectoryInsteadOfFile:
	test	al, FLG_FILEDIALOG_DIRECTORY
	jz		SHORT ReturnWithoutHandlingKeystroke
	; Fall to CloseFileDialogAfterSuccessfulSelection
%endif ; EXCLUDE_FROM_XTIDECFG

;--------------------------------------------------------------------
; CloseFileDialogAfterSuccessfulSelection
;	Parameters:
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing (exits dialog)
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
CloseFileDialogAfterSuccessfulSelection:
	lds		di, [bp+DIALOG.fpDialogIO]
	mov		BYTE [di+FILE_DIALOG_IO.bUserCancellation], FALSE
	jmp		MenuInit_CloseMenuWindow


;--------------------------------------------------------------------
; HandleFunctionKeyForDriveChange
;	Parameters:
;		AL:		File dialog flags
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
HandleFunctionKeyForDriveChange:
	test	al, FLG_FILEDIALOG_DRIVES
	jz		SHORT ReturnWithoutHandlingKeystroke

	call	DisplayLoadingMessageInInformationArea
	mov		cl, DRIVE_DIALOG_IO_size
	call	Memory_ReserveCLbytesFromStackToDSSI
	call	.DisplayDriveSelectionDialogWithIoInDSSI
	call	.ChangeDriveToUserSelectionFromIoInDSSI
	add		sp, BYTE DRIVE_DIALOG_IO_size
.UserCancelledDriveChange:
	ret

;--------------------------------------------------------------------
; .DisplayDriveSelectionDialogWithIoInDSSI
;	Parameters:
;		DS:SI:	Ptr to uninitialized DRIVE_DIALOG_IO
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		DS:SI:	Ptr to DRIVE_DIALOG_IO
;	Corrupts registers:
;		AX, DI
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.DisplayDriveSelectionDialogWithIoInDSSI:
	call	InitializeNullStringsToDialogInputInDSSI
	mov		WORD [si+DIALOG_INPUT.fszTitle], g_szSelectNewDrive
	JMP_MENU_LIBRARY GetDriveWithIoInDSSI

;--------------------------------------------------------------------
; .ChangeDriveToUserSelectionFromIoInDSSI
;	Parameters:
;		DS:SI:	Ptr to DRIVE_DIALOG_IO
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		All, except BP
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
.ChangeDriveToUserSelectionFromIoInDSSI:
	cmp		BYTE [si+DRIVE_DIALOG_IO.bUserCancellation], FALSE
	jne		SHORT .UserCancelledDriveChange

	; Install our Custom Critical Error Handler to catch "Drive Not Ready" errors. This handler only works on DOS 3.0+ systems
	; but that should be OK because only DOS 3.1+ will trigger it. Under older DOS versions drives are enumerated using
	; GET_DOS_DRIVE_PARAMETER_BLOCK_FOR_SPECIFIC_DRIVE which will access the drive so we know it is available at this point.
	mov		dx, DosCritical_CustomHandler
	call	DosCritical_InstallNewHandlerFromCSDX

	; Save the current drive on stack in case the selected drive is not ready and the user decides to cancel the change.
	call	Drive_GetDefaultToAL
	xchg	dx, ax

.RetryDrive:
	push	dx									; Save the previous current drive to stack

	mov		dl, [si+DRIVE_DIALOG_IO.bReturnDriveNumber]
	call	Drive_SetDefaultFromDL

	; Now we must try to force a media access to catch "Drive Not Ready".
	push	ds
	push	ss
	pop		ds
	ePUSH_T	ax, CURRENTDIR_CHARACTERS			; The high byte is zero
	mov		cx, FLG_FILEATTR_DIRECTORY
	mov		dx, sp
	mov		ax, FIND_FIRST_MATCHING_FILE<<8
	int		DOS_INTERRUPT_21h
	; Returns ERR_DOS_NO_MORE_FILES only when the root directory is the current directory (at least under Windows XP).
	cmp		al, ERR_DOS_PATH_NOT_FOUND
	pop		ax
	pop		ds

	pop		dx									; Restore the previous current drive from stack

	xchg	ah, [cs:bLastCriticalError]			; Zero bLastCriticalError and fetch error code to AH
	je		SHORT .DriveIsNotReady				; A removable drive with no media (or possibly a drive that has not been formatted?)
	cmp		ah, ERR_DOS_DRIVE_NOT_READY
	jne		SHORT .DriveIsReady
.DriveIsNotReady:
	mov		bx, g_szDlgDriveNotReady
	call	Dialogs_DisplayYesNoResponseDialogWithTitleStringInBX
	jz		SHORT .RetryDrive
	; The user cancelled the drive change. Restore current drive to what it was previously.
	call	Drive_SetDefaultFromDL
	jmp		DosCritical_RestoreDosHandler

.DriveIsReady:
	call	DosCritical_RestoreDosHandler
	jmp		RefreshFilesToDisplay


;--------------------------------------------------------------------
; DisplayLoadingMessageInInformationArea
;	Parameters:
;		SS:BP:		Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX, BX, CX, DX, SI, DI
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
DisplayLoadingMessageInInformationArea:
	call	MenuText_ClearInformationArea
	call	MenuText_PrepareToDrawInformationArea
	mov		si, g_szLoadingPleaseWait
	JMP_DISPLAY_LIBRARY PrintNullTerminatedStringFromCSSI


;--------------------------------------------------------------------
; InitializeNullStringsToDialogInputInDSSI
;	Parameters:
;		DS:SI:	Ptr to DIALOG_INPUT
;		SS:BP:	Ptr to DIALOG
;	Returns:
;		Nothing
;	Corrupts registers:
;		AX
;--------------------------------------------------------------------
ALIGN JUMP_ALIGN
InitializeNullStringsToDialogInputInDSSI:
	mov		ax, g_szNull
	mov		[si+DIALOG_INPUT.fszTitle], ax
	mov		[si+DIALOG_INPUT.fszTitle+2], cs
	mov		[si+DIALOG_INPUT.fszItems], ax
	mov		[si+DIALOG_INPUT.fszItems+2], cs
	mov		[si+DIALOG_INPUT.fszInfo], ax
	mov		[si+DIALOG_INPUT.fszInfo+2], cs
	ret