From 07c791331c507334f33fececbfeb68b97c89a44d Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Mon, 10 Feb 2014 20:48:08 -0500
Subject: [PATCH] Improved program appearance by setting the correct font,
 colors, and other styles.

---
 common.go  |  3 +++
 main.go    | 22 ++++++++++++++--
 stdfont.go | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 windows.go | 22 ++++++++++++++++
 4 files changed, 118 insertions(+), 2 deletions(-)
 create mode 100644 stdfont.go

diff --git a/common.go b/common.go
index 51ebf6f..79d6fc9 100644
--- a/common.go
+++ b/common.go
@@ -12,6 +12,7 @@ import (
 var (
 	user32 = syscall.NewLazyDLL("user32.dll")
 	kernel32 = syscall.NewLazyDLL("kernel32.dll")
+	gdi32 = syscall.NewLazyDLL("gdi32.dll")
 )
 
 type HANDLE uintptr
@@ -21,6 +22,8 @@ type HMENU HANDLE
 
 const (
 	NULL = 0
+	FALSE = 0			// from windef.h
+	TRUE = 1			// from windef.h
 )
 
 type ATOM uint16
diff --git a/main.go b/main.go
index 9a425b6..7129a7e 100644
--- a/main.go
+++ b/main.go
@@ -106,6 +106,14 @@ func wndProc(hwnd HWND, msg uint32, wParam WPARAM, lParam LPARAM) LRESULT {
 	panic("unreachable")
 }
 
+func setFontAll(hwnd HWND, lParam LPARAM) (cont bool) {
+	_, err := SendMessage(hwnd, WM_SETFONT, WPARAM(lParam), LPARAM(TRUE))
+	if err != nil {
+		fatalf("error setting window font: %v", err)
+	}
+	return true
+}
+
 const className = "mainwin"
 
 func main() {
@@ -119,6 +127,10 @@ func main() {
 	if err != nil {
 		fatalf("error getting WinMain nCmdShow: %v", err)
 	}
+	font, err := getStandardWindowFont()
+	if err != nil {
+		fatalf("error getting standard window font: %v", err)
+	}
 
 	icon, err := LoadIcon_ResourceID(NULL, IDI_APPLICATION)
 	if err != nil {
@@ -135,7 +147,7 @@ func main() {
 		HInstance:		hInstance,
 		HIcon:			icon,
 		HCursor:			cursor,
-		HbrBackground:	HBRUSH(COLOR_WINDOW + 1),
+		HbrBackground:	HBRUSH(COLOR_BTNFACE + 1),
 	}
 	_, err = RegisterClass(wc)
 	if err != nil {
@@ -143,7 +155,7 @@ func main() {
 	}
 
 	hwnd, err := CreateWindowEx(
-		WS_EX_OVERLAPPEDWINDOW,
+		0,
 		className, "Main Window",
 		WS_OVERLAPPEDWINDOW,
 		CW_USEDEFAULT, CW_USEDEFAULT, 320, 240,
@@ -249,6 +261,12 @@ func main() {
 		fatalf("error creating checkbox: %v", err)
 	}
 
+	setFontAll(hwnd, LPARAM(font))
+	err = EnumChildWindows(hwnd, setFontAll, LPARAM(font))
+	if err != nil {
+		fatalf("error setting font on controls: %v", err)
+	}
+
 	_, err = ShowWindow(hwnd, nCmdShow)
 	if err != nil {
 		fatalf("error showing window: %v", err)
diff --git a/stdfont.go b/stdfont.go
new file mode 100644
index 0000000..276b0ed
--- /dev/null
+++ b/stdfont.go
@@ -0,0 +1,73 @@
+// 10 february 2014
+package main
+
+import (
+//	"syscall"
+	"unsafe"
+)
+
+const (
+	SPI_GETNONCLIENTMETRICS = 0x0029
+	LF_FACESIZE = 32		// from wingdi.h
+)
+
+type LOGFONT struct {
+	lfHeight			int32
+	lfWidth			int32
+	lfEscapement		int32
+	lfOrientation		int32
+	lfWeight			int32
+	lfItalic			byte
+	lfUnderline		byte
+	lfStrikeOut		byte
+	lfCharSet			byte
+	lfOutPrecision		byte
+	lfClipPrecision		byte
+	lfQuality			byte
+	lfPitchAndFamily	byte
+	lfFaceName		[LF_FACESIZE]uint16
+}
+
+type NONCLIENTMETRICS struct {
+	cbSize			uint32
+	iBorderWidth		int
+	iScrollWidth		int
+	iScrollHeight		int
+	iCaptionWidth		int
+	iCaptionHeight		int
+	lfCaptionFont		LOGFONT
+	iSmCaptionWidth	int
+	iSmCaptionHeight	int
+	lfSmCaptionFont	LOGFONT
+	iMenuWidth		int
+	iMenuHeight		int
+	lfMenuFont		LOGFONT
+	lfStatusFont		LOGFONT
+	lfMessageFont		LOGFONT
+}
+
+var (
+	systemParametersInfo = user32.NewProc("SystemParametersInfoW")
+	createFontIndirect = gdi32.NewProc("CreateFontIndirectW")
+)
+
+// TODO adorn errors with which step failed?
+func getStandardWindowFont() (hfont HANDLE, err error) {
+	var ncm NONCLIENTMETRICS
+
+	ncm.cbSize = uint32(unsafe.Sizeof(ncm))
+	r1, _, err := systemParametersInfo.Call(
+		uintptr(SPI_GETNONCLIENTMETRICS),
+		uintptr(unsafe.Sizeof(ncm)),
+		uintptr(unsafe.Pointer(&ncm)),
+		0)
+	if r1 == 0 {		// failure
+		return NULL, err
+	}
+	// TODO does this specify an error?
+	r1, _, err = createFontIndirect.Call(uintptr(unsafe.Pointer(&ncm.lfMessageFont)))
+	if r1 == 0 {		// failure
+		return NULL, err
+	}
+	return HANDLE(r1), nil
+}
diff --git a/windows.go b/windows.go
index 6f0f4c1..de6fd6f 100644
--- a/windows.go
+++ b/windows.go
@@ -134,6 +134,7 @@ const (
 var (
 	createWindowEx = user32.NewProc("CreateWindowExW")
 	destroyWindow = user32.NewProc("DestroyWindow")
+	enumChildWindows = user32.NewProc("EnumChildWindows")
 	showWindow = user32.NewProc("ShowWindow")
 )
 
@@ -166,6 +167,27 @@ func DestroyWindow(hWnd HWND) (err error) {
 	return nil
 }
 
+type WNDENUMPROC func(hwnd HWND, lParam LPARAM) (cont bool)
+type _WNDENUMPROC func(hwnd HWND, lParam LPARAM) int
+
+func enumChildProc(p WNDENUMPROC) _WNDENUMPROC {
+	return func(hwnd HWND, lParam LPARAM) int {
+		if p(hwnd, lParam) {
+			return TRUE
+		}
+		return FALSE
+	}
+}
+
+// TODO figure out how to handle errors
+func EnumChildWindows(hWndParent HWND, lpEnumFunc WNDENUMPROC, lParam LPARAM) (err error) {
+	enumChildWindows.Call(
+		uintptr(hWndParent),
+		syscall.NewCallback(enumChildProc(lpEnumFunc)),
+		uintptr(lParam))
+	return nil
+}
+
 // TODO figure out how to handle errors
 func ShowWindow(hWnd HWND, nCmdShow int) (previouslyVisible bool, err error) {
 	r1, _, _ := showWindow.Call(