From d9b9a9a74346c4933a11e2369d56a22cf51b12aa Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Sun, 17 Aug 2014 17:22:47 -0400
Subject: [PATCH] Implemented hover-to-hot on Windows Table checkboxes.

---
 redo/table_windows.c  | 20 ++++++++++++++++++++
 redo/table_windows.go | 20 ++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/redo/table_windows.c b/redo/table_windows.c
index 775d4e6..357da25 100644
--- a/redo/table_windows.c
+++ b/redo/table_windows.c
@@ -6,6 +6,22 @@
 // provided for cgo's benefit
 LPWSTR xWC_LISTVIEW = WC_LISTVIEW;
 
+static void handleMouseMove(HWND hwnd, WPARAM wParam, LPARAM lParam, void *data)
+{
+	LVHITTESTINFO ht;
+
+	// TODO use wParam
+	ZeroMemory(&ht, sizeof (LVHITTESTINFO));
+	ht.pt.x = GET_X_LPARAM(lParam);
+	ht.pt.y = GET_Y_LPARAM(lParam);
+	ht.flags = LVHT_ONITEMSTATEICON;
+	if (SendMessageW(hwnd, LVM_SUBITEMHITTEST, 0, (LPARAM) (&ht)) == (LRESULT) -1) {
+		tableSetHot(data, -1, -1);
+		return;		// no item
+	}
+	tableSetHot(data, ht.iItem, ht.iSubItem);
+}
+
 static LRESULT CALLBACK tableSubProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR id, DWORD_PTR data)
 {
 	NMHDR *nmhdr = (NMHDR *) lParam;
@@ -19,6 +35,10 @@ static LRESULT CALLBACK tableSubProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM
 			return 0;
 		}
 		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	case WM_MOUSEMOVE:
+		handleMouseMove(hwnd, wParam, lParam, (void *) data);
+		// and let the list view do its thing
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
 	// see table.autoresize() in table_windows.go for the column autosize policy
 	case WM_NOTIFY:		// from the contained header control
 		if (nmhdr->code == HDN_BEGINTRACK)
diff --git a/redo/table_windows.go b/redo/table_windows.go
index c90a6fa..83e6cd1 100644
--- a/redo/table_windows.go
+++ b/redo/table_windows.go
@@ -16,6 +16,8 @@ type table struct {
 	_hwnd		C.HWND
 	noautosize	bool
 	colcount		C.int
+	hotrow		C.int
+	hotcol		C.int
 }
 
 func finishNewTable(b *tablebase, ty reflect.Type) Table {
@@ -24,6 +26,8 @@ func finishNewTable(b *tablebase, ty reflect.Type) Table {
 			C.LVS_REPORT | C.LVS_OWNERDATA | C.LVS_NOSORTHEADER | C.LVS_SHOWSELALWAYS | C.WS_HSCROLL | C.WS_VSCROLL | C.WS_TABSTOP,
 			C.WS_EX_CLIENTEDGE),		// WS_EX_CLIENTEDGE without WS_BORDER will show the canonical visual styles border (thanks to MindChild in irc.efnet.net/#winprog)
 		tablebase:		b,
+		hotrow:		-1,
+		hotcol:		-1,
 	}
 	C.setTableSubclass(t._hwnd, unsafe.Pointer(t))
 	// LVS_EX_FULLROWSELECT gives us selection across the whole row, not just the leftmost column; this makes the list view work like on other platforms
@@ -77,6 +81,11 @@ func tableGetCell(data unsafe.Pointer, item *C.LVITEMW) {
 		} else {
 			curstate &^= C.checkboxStateChecked
 		}
+		if item.iItem == t.hotrow && item.iSubItem == t.hotcol {
+			curstate |= C.checkboxStateHot
+		} else {
+			curstate &^= C.checkboxStateHot
+		}
 		item.state = (curstate + 1) << 12
 	default:
 		s := fmt.Sprintf("%v", datum)
@@ -106,6 +115,17 @@ func tableColumnCount(data unsafe.Pointer) C.int {
 	return t.colcount
 }
 
+//export tableSetHot
+func tableSetHot(data unsafe.Pointer, row C.int, col C.int) {
+	t := (*table)(data)
+	redraw := (row != t.hotrow || col != t.hotcol)
+	t.hotrow = row
+	t.hotcol = col
+	if redraw {
+		C.tableUpdate(t._hwnd, C.int(reflect.Indirect(reflect.ValueOf(t.data)).Len()))
+	}
+}
+
 func (t *table) hwnd() C.HWND {
 	return t._hwnd
 }