Odin/core/sys/windows/comdlg32.odin

// +build windows
package sys_windows

foreign import "system:Comdlg32.lib"

LPOFNHOOKPROC :: #type proc "stdcall" (hdlg: HWND, msg: u32, wparam: WPARAM, lparam: LPARAM) -> UINT_PTR

OPENFILENAMEW :: struct {
	lStructSize: 	        DWORD,
	hwndOwner: 	        HWND,
	hInstance: 	        HINSTANCE,
	lpstrFilter: 	        wstring,
	lpstrCustomFilter: 	wstring,
	nMaxCustFilter: 	DWORD,
	nFilterIndex: 	        DWORD,
	lpstrFile: 	        wstring,
	nMaxFile: 	        DWORD,
	lpstrFileTitle: 	wstring,
	nMaxFileTitle: 	        DWORD,
	lpstrInitialDir: 	wstring,
	lpstrTitle: 	        wstring,
	Flags: 	                DWORD,
	nFileOffset: 	        WORD,
	nFileExtension: 	WORD,
	lpstrDefExt: 	        wstring,
	lCustData: 	        LPARAM,
	lpfnHook: 	        LPOFNHOOKPROC,
	lpTemplateName: 	wstring,
	pvReserved:             rawptr,
	dwReserved:             DWORD,
	FlagsEx:                DWORD,
}

@(default_calling_convention="stdcall")
foreign Comdlg32 {
	GetOpenFileNameW     :: proc(arg1: ^OPENFILENAMEW) -> BOOL ---
	GetSaveFileNameW     :: proc(arg1: ^OPENFILENAMEW) -> BOOL ---
	CommDlgExtendedError :: proc() -> u32 ---
}

OPEN_TITLE :: "Select file to open"
OPEN_FLAGS :: u32(OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST)
OPEN_FLAGS_MULTI :: OPEN_FLAGS | OFN_ALLOWMULTISELECT | OFN_EXPLORER

SAVE_TITLE :: "Select file to save"
SAVE_FLAGS :: u32(OFN_OVERWRITEPROMPT | OFN_EXPLORER)
SAVE_EXT   :: "txt"

/*
import "core:strings"

Open_Save_Mode :: enum {
	Open = 0,
	Save = 1,
}

_open_file_dialog :: proc(title: string, dir: string,
                          filters: []string, default_filter: u32,
                          flags: u32, default_ext: string,
                          mode: Open_Save_Mode, allocator := context.temp_allocator) -> (path: string, ok: bool = true) {
	context.allocator = allocator
	file_buf := make([]u16, MAX_PATH_WIDE)
	defer if !ok {
		delete(file_buf)
	}

	// Filters need to be passed as a pair of strings (title, filter)
	filter_len := u32(len(filters))
	if filter_len % 2 != 0 {
		return "", false
	}

	filter: string
	filter = strings.join(filters, "\u0000", context.temp_allocator)
	filter = strings.concatenate({filter, "\u0000"}, context.temp_allocator)

	ofn := OPENFILENAMEW{
		lStructSize     = size_of(OPENFILENAMEW),
		lpstrFile       = wstring(&file_buf[0]),
		nMaxFile        = MAX_PATH_WIDE,
		lpstrTitle      = utf8_to_wstring(title, context.temp_allocator),
		lpstrFilter     = utf8_to_wstring(filter, context.temp_allocator),
		lpstrInitialDir = utf8_to_wstring(dir, context.temp_allocator),
		nFilterIndex    = u32(clamp(default_filter, 1, filter_len / 2)),
		lpstrDefExt     = utf8_to_wstring(default_ext, context.temp_allocator),
		Flags           = u32(flags),
	}

	switch mode {
	case .Open:
		ok = bool(GetOpenFileNameW(&ofn))
	case .Save:
		ok = bool(GetSaveFileNameW(&ofn))
	case:
		ok = false
	}

	if !ok {
		return
	}


	file_name, _ := utf16_to_utf8(file_buf[:], allocator)
	path = strings.trim_right_null(file_name)
	return
}

select_file_to_open :: proc(title := OPEN_TITLE, dir := ".",
                            filters := []string{"All Files", "*.*"}, default_filter := u32(1),
                            flags := OPEN_FLAGS, allocator := context.temp_allocator) -> (path: string, ok: bool) {

	path, ok = _open_file_dialog(title, dir, filters, default_filter, flags, "", Open_Save_Mode.Open, allocator)
	return
}

select_file_to_save :: proc(title := SAVE_TITLE, dir := ".",
                            filters := []string{"All Files", "*.*"}, default_filter := u32(1),
                            flags := SAVE_FLAGS, default_ext := SAVE_EXT,
                            allocator := context.temp_allocator) -> (path: string, ok: bool) {

	path, ok = _open_file_dialog(title, dir, filters, default_filter, flags, default_ext, Open_Save_Mode.Save, allocator)
	return
}
*/

// TODO: Implement convenience function for select_file_to_open with ALLOW_MULTI_SELECT that takes
//       it output of the form "path\u0000\file1u\0000file2" and turns it into []string with the path + file pre-concatenated for you.

OFN_ALLOWMULTISELECT     :: 0x00000200 // NOTE(Jeroen): Without OFN_EXPLORER it uses the Win3 dialog.
OFN_CREATEPROMPT         :: 0x00002000
OFN_DONTADDTORECENT      :: 0x02000000
OFN_ENABLEHOOK           :: 0x00000020
OFN_ENABLEINCLUDENOTIFY  :: 0x00400000
OFN_ENABLESIZING         :: 0x00800000
OFN_ENABLETEMPLATE       :: 0x00000040
OFN_ENABLETEMPLATEHANDLE :: 0x00000080
OFN_EXPLORER             :: 0x00080000
OFN_EXTENSIONDIFFERENT   :: 0x00000400
OFN_FILEMUSTEXIST        :: 0x00001000
OFN_FORCESHOWHIDDEN      :: 0x10000000
OFN_HIDEREADONLY         :: 0x00000004
OFN_LONGNAMES            :: 0x00200000
OFN_NOCHANGEDIR          :: 0x00000008
OFN_NODEREFERENCELINKS   :: 0x00100000
OFN_NOLONGNAMES          :: 0x00040000
OFN_NONETWORKBUTTON      :: 0x00020000
OFN_NOREADONLYRETURN     :: 0x00008000
OFN_NOTESTFILECREATE     :: 0x00010000
OFN_NOVALIDATE           :: 0x00000100
OFN_OVERWRITEPROMPT      :: 0x00000002
OFN_PATHMUSTEXIST        :: 0x00000800
OFN_READONLY             :: 0x00000001
OFN_SHAREAWARE           :: 0x00004000
OFN_SHOWHELP             :: 0x00000010

CDERR_DIALOGFAILURE      :: 0x0000FFFF
CDERR_GENERALCODES       :: 0x00000000
CDERR_STRUCTSIZE         :: 0x00000001
CDERR_INITIALIZATION     :: 0x00000002
CDERR_NOTEMPLATE         :: 0x00000003
CDERR_NOHINSTANCE        :: 0x00000004
CDERR_LOADSTRFAILURE     :: 0x00000005
CDERR_FINDRESFAILURE     :: 0x00000006
CDERR_LOADRESFAILURE     :: 0x00000007
CDERR_LOCKRESFAILURE     :: 0x00000008
CDERR_MEMALLOCFAILURE    :: 0x00000009
CDERR_MEMLOCKFAILURE     :: 0x0000000A
CDERR_NOHOOK             :: 0x0000000B
CDERR_REGISTERMSGFAIL    :: 0x0000000C