Convert to C++.

I already hit upon some object-oriented programming patterns in
*listview.c, so I felt that it would be natural to use this as an
opportunity to learn C++.

12 files changed, 453 insertions, 404 deletions

diff --git a/.dir-locals.el b/.dir-locals.el
index 62e25f6..6c6dcc0 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -1,2 +1,4 @@
 ((c-mode . ((flycheck-gcc-include-path . ("C:/Program Files/swipl/include"))
-	    (flycheck-gcc-definitions . ("UNICODE" "_UNICODE")))))
+	    (flycheck-gcc-definitions . ("UNICODE" "_UNICODE"))))
+ (c++-mode . ((flycheck-gcc-include-path . ("C:/Program Files/swipl/include"))
+	      (flycheck-gcc-definitions . ("UNICODE" "_UNICODE")))))
diff --git a/.gitignore b/.gitignore
index 9270add..44b07c6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 /misc/
 TAGS
 *~
+*.db
diff --git a/Makefile b/Makefile
index 405e8c6..99b5f28 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 B = build/default/
 
-C = c/main.c
+C = c/main.cpp
 PL = pl/cfg.pl pl/episode_data.pl pl/local_episodes.pl pl/track_episodes.pl
 OBJ = $(B)common.obj $(B)datalistview.obj $(B)episodelistview.obj $(B)listview.obj $(B)pl.obj $(B)resource.obj
 
@@ -18,11 +18,11 @@ $(B)EpisodeBrowser.exe: $(C) $(OBJ) $(PL) c/defs.h Makefile
 $(B)resource.obj: c/resource.h c/resource.rc c/application.manifest
 	windres -i c/resource.rc -o $(B)resource.obj
 
-$(B)%.obj: c/%.c c/defs.h
+$(B)%.obj: c/%.cpp c/*.h
 	$(CC) -c $(CFLAGS) -o $@ $<
 
-TAGS: c/*.c c/*.h pl/*.pl
-	etags c/*.c c/*.h -lprolog pl/*.pl
+TAGS: c/*.cpp c/*.h pl/*.pl
+	etags c/*.cpp c/*.h -lprolog pl/*.pl
 
 clean:
 	rm -fr $(B)EpisodeBrowser.exe $(B)*.obj
diff --git a/README b/README
index d6ceca7..489103e 100644
--- a/README
+++ b/README
@@ -28,16 +28,16 @@ modified.
 
 Frontend
 ~~~~~~~~
-The graphical interface is implemented in C using the Win32 API (see
+The graphical interface is implemented in C++ using the Win32 API (see
 the c folder). The source code is spread across a small number of
 files. For an overview of the functions provided by each file, see
 defs.h. In summary:
 
-main.c			Entry point and initialization. Contains the main event handler.
-listview.c		Creates and handles the shared aspects of the two list views.
-episodelistview.c	Defines the interface to the episode list view.
-datalistview.c		Defines the interface to the data list view.
-common.c		Some useful functions that don't fit elsewhere.
+main.cpp		Entry point and initialization. Contains the main event handler.
+listview.cpp		Creates and handles the shared aspects of the two list views.
+episodelistview.cpp	Defines the interface to the episode list view.
+datalistview.cpp	Defines the interface to the data list view.
+common.cpp		Some useful functions that don't fit elsewhere.
 
 The frontend interacts with the Prolog backend via the SWI-Prolog API.
 Note, however, that most interaction is done through ten or so macros,
diff --git a/c/common.c b/c/common.cpp
index a056993..63adb53 100644
--- a/c/common.c
+++ b/c/common.cpp
@@ -15,7 +15,7 @@ TszFromSz(const char *sz, int iCp)
 
 	cbMultiByte = strlen(sz)+1;
 	cchWideChar = MultiByteToWideChar(iCp, 0, sz, cbMultiByte, NULL, 0);
-	tsz = malloc(cchWideChar*sizeof(WCHAR));
+	tsz = (TCHAR *)malloc(cchWideChar*sizeof(WCHAR));
 	if (!tsz) return NULL;
 	if (!MultiByteToWideChar(iCp, 0, sz, cbMultiByte, tsz, cchWideChar))
 		return NULL;
diff --git a/c/datalistview.c b/c/datalistview.cpp
index fbb46d0..3269dab 100644
--- a/c/datalistview.c
+++ b/c/datalistview.cpp
@@ -6,42 +6,38 @@
 #include "resource.h"
 #include "defs.h"
 
-HWND HDlv;
+extern EpisodeListView g_elv;
 
-HWND
-DlvCreate()
+void
+DataListView::Create()
 {
 	LVCOLUMN lvc;
 
-	HDlv = LvCreate((HMENU)IDC_DATALISTVIEW, LVS_NOCOLUMNHEADER);
+	ListView::Create((HMENU)IDC_DATALISTVIEW, LVS_NOCOLUMNHEADER);
 
 	lvc.mask = LVCF_WIDTH|LVCF_TEXT|LVCF_SUBITEM;
 	lvc.iSubItem = DLVSIKEY;
 	lvc.pszText = TEXT("Key");
 
 	lvc.cx = Dpi(42);
-	ListView_InsertColumn(HDlv, DLVSIKEY, &lvc);
+	ListView_InsertColumn(m_hWnd, DLVSIKEY, &lvc);
 
 	lvc.iSubItem = DLVSIVALUE;
 	lvc.pszText = TEXT("Value");
 	lvc.cx = 500;
-	ListView_InsertColumn(HDlv, DLVSIVALUE, &lvc);
-
-	return HDlv;
+	ListView_InsertColumn(m_hWnd, DLVSIVALUE, &lvc);
 }
 
-/* Show episode data. */
 void
-DlvShowEpisode(int iEpisode)
+DataListView::ShowEpisode(int iEpisode)
 {
 	int i, iItem;
 	LVFINDINFO lvfi;
 	LVITEM lviKey, lviValue;
 	term_t t;
 	qid_t q;
-	extern HWND HElv;
 
-	ListView_DeleteAllItems(HDlv);
+	ListView_DeleteAllItems(m_hWnd);
 
 	lviKey.mask = LVIF_TEXT;
 	lviValue.mask = LVIF_TEXT;
@@ -67,12 +63,12 @@ DlvShowEpisode(int iEpisode)
 		lviKey.iItem = i;
 		lviKey.iSubItem = 0;
 		lviKey.pszText = tszKey;
-		ListView_InsertItem(HDlv, &lviKey);
+		ListView_InsertItem(m_hWnd, &lviKey);
 
 		lviValue.iItem = i;
 		lviValue.iSubItem = 1;
 		lviValue.pszText = tszValue;
-		ListView_SetItem(HDlv, &lviValue);
+		ListView_SetItem(m_hWnd, &lviValue);
 
 		free(tszValue);
 	c:	free(tszKey);
@@ -83,7 +79,7 @@ DlvShowEpisode(int iEpisode)
 
 	lvfi.flags = LVFI_PARAM;
 	lvfi.lParam = iEpisode;
-	iItem = ListView_FindItem(HElv, -1, &lvfi);
+	iItem = ListView_FindItem(g_elv.HWnd(), -1, &lvfi);
 	if (iItem != -1)
-		ListView_EnsureVisible(HElv, iItem, TRUE);
+		ListView_EnsureVisible(g_elv.HWnd(), iItem, TRUE);
 }
diff --git a/c/defs.h b/c/defs.h
index 8196a93..9f53c92 100644
--- a/c/defs.h
+++ b/c/defs.h
@@ -5,36 +5,51 @@
 #include <commctrl.h>
 #include <SWI-Prolog.h>
 
-/* common.c */
+/* common.cpp */
 TCHAR *TszFromSz(const char *, int);
 
-/* main.c */
+/* main.cpp */
 void UpdateLayout();
 
-/* listview.c */
-HWND LvCreate(HMENU, DWORD);
-int LvHeight(HWND, int);
-
-/* episodelistview.c */
-HWND ElvCreate();
-void ElvDoSort(void);
-LRESULT ElvHandleNotify(LPARAM);
-void ElvRedraw(void);
-void ElvSetTop(int);
-void ElvSelectFocus(void);
-void ElvSelectUnwatched(int);
-void ElvShowFocus(void);
-void ElvUpdate(void);
-void ElvUpdateItem(LPLVITEM);
-
-/* datalistview.c */
-HWND DlvCreate();
-void DlvShowEpisode(int);
-
-/* pl.c */
-int Pl(char *, char *, char *, ...);
-int Plp(term_t, char *, ...);
-int Plg(term_t, char *, ...);
+/* listview.cpp */
+class ListView {
+protected:
+	WNDPROC m_prevProc;
+	HWND m_hWnd;
+public:
+	void Create(HMENU, DWORD);
+	int Height(int);
+	HWND HWnd(void);
+	virtual LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
+};
+
+/* episodelistview.cpp */
+class EpisodeListView: public ListView {
+public:
+	void Create(void);
+	void DoSort(void);
+	LRESULT HandleNotify(LPARAM);
+	void Redraw(void);
+	void SetTop(int);
+	void SelectFocus(void);
+	void SelectUnwatched(int);
+	void ShowFocus(void);
+	void Update(void);
+	void UpdateItem(LPLVITEM);
+	LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
+};
+
+/* datalistview.cpp */
+class DataListView: public ListView {
+public:
+	void Create(void);
+	void ShowEpisode(int);
+};
+
+/* pl.cpp */
+int Pl(const char *, const char *, const char *, ...);
+int Plp(term_t, const char *, ...);
+int Plg(term_t, const char *, ...);
 
 /* defs.h */
 #define DLVSIKEY 0
@@ -56,8 +71,8 @@ Cmp(int a, int b)
 inline int
 Dpi(int i)
 {
-	extern int IDPI;
-	return MulDiv(i, IDPI, 96);
+	extern int g_iDPI;
+	return MulDiv(i, g_iDPI, 96);
 }
 
 #endif
diff --git a/c/episodelistview.c b/c/episodelistview.cpp
index a1973f8..8fb3ec7 100644
--- a/c/episodelistview.c
+++ b/c/episodelistview.cpp
@@ -6,48 +6,50 @@
 #include "resource.h"
 #include "defs.h"
 
-HWND HElv;
+extern DataListView g_dlv;
+
+HWND HSortLv;
+
 int ISort;
 LVITEM LviElvFocus;	/* Focused episode. */
 static int CALLBACK ElvSort(LPARAM, LPARAM, LPARAM);
 
-HWND
-ElvCreate()
+void
+EpisodeListView::Create()
 {
 	LVCOLUMN lvc;
 
-	HElv = LvCreate((HMENU)IDC_EPISODELISTVIEW, 0);
+	ListView::Create((HMENU)IDC_EPISODELISTVIEW, 0);
 
 	lvc.mask = LVCF_WIDTH|LVCF_TEXT|LVCF_SUBITEM;
 	lvc.iSubItem = ELVSIEPISODE;
 	lvc.pszText = TEXT("#");
 	lvc.cx = Dpi(42);
-	ListView_InsertColumn(HElv, ELVSIEPISODE, &lvc);
+	ListView_InsertColumn(m_hWnd, ELVSIEPISODE, &lvc);
 
 	lvc.iSubItem = ELVSITITLE;
 	lvc.pszText = TEXT("Title");
 	lvc.cx = 500;
-	ListView_InsertColumn(HElv, ELVSITITLE, &lvc);
+	ListView_InsertColumn(m_hWnd, ELVSITITLE, &lvc);
 
 	lvc.iSubItem = ELVSIRATING;
 	lvc.pszText = TEXT("/");
 	lvc.cx = Dpi(30);
-	ListView_InsertColumn(HElv, ELVSIRATING, &lvc);
+	ListView_InsertColumn(m_hWnd, ELVSIRATING, &lvc);
 
 	if (!Pl("cfg","get_sort","i",&ISort))
 		ISort = 1;
-
-	return HElv;
 }
 
 void
-ElvDoSort()
+EpisodeListView::DoSort()
 {
-	ListView_SortItemsEx(HElv, ElvSort, ISort);
+	HSortLv = m_hWnd;
+	ListView_SortItemsEx(m_hWnd, ElvSort, ISort);
 }
 
 LRESULT
-ElvHandleNotify(LPARAM lParam)
+EpisodeListView::HandleNotify(LPARAM lParam)
 {
 	LPNMLISTVIEW lpNmLv;
 	lpNmLv = (LPNMLISTVIEW)lParam;
@@ -58,8 +60,8 @@ ElvHandleNotify(LPARAM lParam)
 		    (lpNmLv->uNewState & LVIS_FOCUSED)) {
 			LviElvFocus.iItem = lpNmLv->iItem;
 			LviElvFocus.lParam = lpNmLv->lParam;
-			ElvUpdateItem(&LviElvFocus);
-			DlvShowEpisode(lpNmLv->lParam);
+			UpdateItem(&LviElvFocus);
+			g_dlv.ShowEpisode(lpNmLv->lParam);
 		}
 		break;
 	case LVN_COLUMNCLICK:	/* Sort by column. */
@@ -68,8 +70,8 @@ ElvHandleNotify(LPARAM lParam)
 		iColumn = lpNmLv->iSubItem+1;
 		ISort = abs(ISort) == iColumn? -ISort: iColumn;
 		Pl("cfg","set_sort","I",ISort);
-	    s:	ElvDoSort();
-		ElvShowFocus();
+		DoSort();
+		ShowFocus();
 		break;
 	    }
 	case LVN_KEYDOWN:	/* Navigate episodes by keyboard. */
@@ -78,10 +80,10 @@ ElvHandleNotify(LPARAM lParam)
 		lpNmLvKd = (LPNMLVKEYDOWN)lParam;
 		switch (lpNmLvKd->wVKey) {
 		case VK_LEFT:
-			ElvSelectUnwatched(-1);
+			SelectUnwatched(-1);
 			break;
 		case VK_RIGHT:
-			ElvSelectUnwatched(1);
+			SelectUnwatched(1);
 			break;
 		}
 		break;
@@ -96,9 +98,9 @@ ElvHandleNotify(LPARAM lParam)
 			break;
 		case CDDS_ITEMPREPAINT:
 		    {
-			extern HFONT HfBold;
+			extern HFONT g_fBold;
 			if (!Pl("track_episodes","watched","I",lpLvCd->nmcd.lItemlParam)) {
-				SelectObject(lpLvCd->nmcd.hdc, HfBold);
+				SelectObject(lpLvCd->nmcd.hdc, g_fBold);
 				return CDRF_NEWFONT;
 			}
 			break;
@@ -117,12 +119,11 @@ ElvHandleNotify(LPARAM lParam)
 	case NM_RETURN:		/* Open all selected episodes. */
 	    {
 		LVITEM lvi;
-		extern HWND HElv;
 		lvi.mask = LVIF_PARAM;
 		lvi.iItem = -1;
 		while ((lvi.iItem = ListView_GetNextItem(
-			    HElv, lvi.iItem, LVNI_SELECTED)) != -1) {
-			if (!ListView_GetItem(HElv, &lvi)) goto b;
+			    m_hWnd, lvi.iItem, LVNI_SELECTED)) != -1) {
+			if (!ListView_GetItem(m_hWnd, &lvi)) goto b;
 			if (!Pl("local_episodes","open_episode_locally","I",
 				lvi.lParam))
 				Pl("local_episodes","open_episode_online","I",
@@ -133,12 +134,12 @@ ElvHandleNotify(LPARAM lParam)
 	case NM_RCLICK:
 	    {
 		DWORD dwPos;
-		extern HWND HWnd;
-		extern HMENU HPopupMenu;
+		extern HWND g_hWnd;
+		extern HMENU g_hPopupMenu;
 		dwPos = GetMessagePos();
-		TrackPopupMenu(HPopupMenu, TPM_RIGHTBUTTON,
+		TrackPopupMenu(g_hPopupMenu, TPM_RIGHTBUTTON,
 		    LOWORD(dwPos), HIWORD(dwPos), 0,
-		    HWnd, NULL);
+		    g_hWnd, NULL);
 		break;
 	    }
 	}
@@ -147,24 +148,24 @@ ElvHandleNotify(LPARAM lParam)
 }
 
 void
-ElvRedraw()
+EpisodeListView::Redraw()
 {
-	RedrawWindow(HElv, NULL, NULL,
+	RedrawWindow(m_hWnd, NULL, NULL,
 	    RDW_ERASE|RDW_FRAME|RDW_INVALIDATE|RDW_ALLCHILDREN);
 }
 
 void
-ElvSetTop(int iItem)
+EpisodeListView::SetTop(int iItem)
 {
 	int iLast;
-	iLast = ListView_GetItemCount(HElv)-1;
-	ListView_EnsureVisible(HElv, iLast, TRUE);
-	ListView_EnsureVisible(HElv, iItem, TRUE);
+	iLast = ListView_GetItemCount(m_hWnd)-1;
+	ListView_EnsureVisible(m_hWnd, iLast, TRUE);
+	ListView_EnsureVisible(m_hWnd, iItem, TRUE);
 }
 
 /* Select previously focused episode. */
 void
-ElvSelectFocus()
+EpisodeListView::SelectFocus()
 {
 	int i, iEpisode, iItem;
 	LVFINDINFO lvfi;
@@ -175,31 +176,31 @@ ElvSelectFocus()
 	lvfi.flags = LVFI_PARAM;
 	lvfi.lParam = iEpisode;
 	i = 0;
-	while ((iItem = ListView_FindItem(HElv, -1, &lvfi)) == -1 && i++ < 100)
+	while ((iItem = ListView_FindItem(m_hWnd, -1, &lvfi)) == -1 && i++ < 100)
 		lvfi.lParam = ++iEpisode;
 	if (iItem != -1) goto s;
 
 	iEpisode -= 100;
 	lvfi.lParam = iEpisode;
 	i = 0;
-	while ((iItem = ListView_FindItem(HElv, -1, &lvfi)) == -1 && i++ < 100)
+	while ((iItem = ListView_FindItem(m_hWnd, -1, &lvfi)) == -1 && i++ < 100)
 		lvfi.lParam = --iEpisode;
 	if (iItem != -1) goto s;
 	return;
 
-s:	ListView_SetItemState(HElv, -1, LVIF_STATE, LVIS_SELECTED);
-	ElvSetTop(iItem > 5? iItem-5: 0);
-	ListView_SetItemState(HElv, iItem,
+s:	ListView_SetItemState(m_hWnd, -1, LVIF_STATE, LVIS_SELECTED);
+	SetTop(iItem > 5? iItem-5: 0);
+	ListView_SetItemState(m_hWnd, iItem,
 	    LVIS_SELECTED|LVIS_FOCUSED, LVIS_SELECTED|LVIS_FOCUSED);
 	LviElvFocus.iItem = iItem;
 	LviElvFocus.lParam = iEpisode;
-	ElvUpdateItem(&LviElvFocus);
-	DlvShowEpisode(iEpisode);
+	UpdateItem(&LviElvFocus);
+	g_dlv.ShowEpisode(iEpisode);
 }
 
 /* Select next/previous unwatched episode. */
 void
-ElvSelectUnwatched(int iDir)
+EpisodeListView::SelectUnwatched(int iDir)
 {
 	int i, iEpNew, iItemNew;
 	LVFINDINFO lvfi;
@@ -207,8 +208,8 @@ ElvSelectUnwatched(int iDir)
 
 	/* Get focused episode. */
 	lviFocus.mask = LVIF_PARAM;
-	if ((lviFocus.iItem = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED)) != -1
-	    && ListView_GetItem(HElv, &lviFocus))
+	if ((lviFocus.iItem = ListView_GetNextItem(m_hWnd, -1, LVNI_FOCUSED)) != -1
+	    && ListView_GetItem(m_hWnd, &lviFocus))
 		;
 	else
 		return;
@@ -223,130 +224,83 @@ ElvSelectUnwatched(int iDir)
 			return;
 
 		lvfi.lParam = iEpNew;
-		if ((iItemNew = ListView_FindItem(HElv, -1, &lvfi)) != -1) {
-			ListView_SetItemState(HElv,-1,LVIF_STATE,LVIS_SELECTED);
-			ListView_SetSelectionMark(HElv, iItemNew);
-			ListView_SetItemState(HElv, iItemNew,
+		if ((iItemNew = ListView_FindItem(m_hWnd, -1, &lvfi)) != -1) {
+			ListView_SetItemState(m_hWnd,-1,LVIF_STATE,LVIS_SELECTED);
+			ListView_SetSelectionMark(m_hWnd, iItemNew);
+			ListView_SetItemState(m_hWnd, iItemNew,
 			    LVIS_SELECTED|LVIS_FOCUSED,
 			    LVIS_SELECTED|LVIS_FOCUSED);
-			ElvRedraw();
-			ListView_EnsureVisible(HElv, iItemNew, TRUE);
+			Redraw();
+			ListView_EnsureVisible(m_hWnd, iItemNew, TRUE);
 			return;
 		}
 	} while (i++ < 1000);
 }
 
 void
-ElvShowFocus()
+EpisodeListView::ShowFocus()
 {
 	int iEpFocus;
-	iEpFocus = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED);
+	iEpFocus = ListView_GetNextItem(m_hWnd, -1, LVNI_FOCUSED);
 	if (iEpFocus == -1) return;
-	ListView_EnsureVisible(HElv, iEpFocus, TRUE);
-}
-
-/* Sort list view items, iSort being the 1-based index of the column
- * to sort by. If iSort is negative, the order is descending. */
-int CALLBACK
-ElvSort(LPARAM iItem1, LPARAM iItem2, LPARAM iSort)
-{
-	int iOrder;
-	LVITEM lvi1, lvi2;
-	lvi1.mask = lvi2.mask = LVIF_PARAM;
-	lvi1.iItem = iItem1; lvi2.iItem = iItem2;
-	if (!ListView_GetItem(HElv, &lvi1)) return 0;
-	if (!ListView_GetItem(HElv, &lvi2)) return 0;
-	iOrder = Cmp(iSort, 0);
-	switch (abs(iSort)-1) {
-	case ELVSIEPISODE:
-		return iOrder*Cmp(lvi1.lParam, lvi2.lParam);
-		break;
-	case ELVSIRATING:
-	    {
-		int iRating1, iRating2;
-		iRating1 = iSort > 0? 99: -1;
-		iRating2 = iSort > 0? 99: -1;
-		Pl("episode_data","episode_rating","Ii",lvi1.lParam,&iRating1);
-		Pl("episode_data","episode_rating","Ii",lvi2.lParam,&iRating2);
-		if (iRating1 == iRating2)
-			return Cmp(lvi1.lParam, lvi2.lParam);
-		return iOrder*Cmp(iRating1, iRating2);
-		break;
-	    }
-	case ELVSITITLE:
-	    {
-		char *sz1, *sz2;
-		int cch, cch1, cch2;
-		if (!Pl("episode_data","episode_title","Is",lvi1.lParam,&sz1))
-			return 0;
-		if (!Pl("episode_data","episode_title","Is",lvi2.lParam,&sz2))
-			return 0;
-		cch1 = strlen(sz1);
-		cch2 = strlen(sz2);
-		cch = cch1 > cch2? cch2: cch1;
-		return iOrder*_strnicmp(sz1, sz2, cch);
-		break;
-	    }
-	default:
-		return 0;
-	}
+	ListView_EnsureVisible(m_hWnd, iEpFocus, TRUE);
 }
 
 /* Update episode list. */
 void
-ElvUpdate()
+EpisodeListView::Update()
 {
 	int cEp, i, iEp, iEpFocus, iItem, iItemMark, iItemTopNew;
 	LVITEM lvi, lviEpisode, lviTop;
 	LVFINDINFO lvfi;
-	extern HWND HWndStatus;
-	static TCHAR tszDisp[16], tszEpisode[16], tszTotal[16];
+	extern HWND g_hWndStatus;
+	static TCHAR tszDisp[16], tszEpisode[16];
 	static int aEpSel[2048];
 
 	lviEpisode.mask = LVIF_TEXT|LVIF_PARAM;
 
 	/* Save scrolling position. */
-	lviTop.iItem = ListView_GetTopIndex(HElv);
+	lviTop.iItem = ListView_GetTopIndex(m_hWnd);
 	lviTop.mask = LVIF_PARAM;
-	ListView_GetItem(HElv, &lviTop);
+	ListView_GetItem(m_hWnd, &lviTop);
 
 	/* Save selected episodes. */
 	i = 0;
 	lvi.mask = LVIF_PARAM;
 	lvi.iItem = -1;
 	while ((lvi.iItem = ListView_GetNextItem(
-		    HElv, lvi.iItem, LVNI_SELECTED)) != -1
+		    m_hWnd, lvi.iItem, LVNI_SELECTED)) != -1
 	    && i < 2048)
-		if (ListView_GetItem(HElv, &lvi))
+		if (ListView_GetItem(m_hWnd, &lvi))
 			aEpSel[i++] = lvi.lParam;
 	aEpSel[i] = 0;
-	iItemMark = ListView_GetSelectionMark(HElv);
+	iItemMark = ListView_GetSelectionMark(m_hWnd);
 
 	/* Save focus. */
 	iEpFocus = 0;
-	if ((lvi.iItem = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED)) != -1
-	    && ListView_GetItem(HElv, &lvi))
+	if ((lvi.iItem = ListView_GetNextItem(m_hWnd, -1, LVNI_FOCUSED)) != -1
+	    && ListView_GetItem(m_hWnd, &lvi))
 		iEpFocus = lvi.lParam;
 
-	SendMessage(HElv, WM_SETREDRAW, FALSE, 0);
-	ListView_DeleteAllItems(HElv);
+	SendMessage(m_hWnd, WM_SETREDRAW, FALSE, 0);
+	ListView_DeleteAllItems(m_hWnd);
 
 	if (!Pl("episode_data","ensure_episode_data","")) return;
 	if (!Pl("episode_data","episode_count","i",&cEp)) return;
 
 	for (iEp = 1, iItem = 0; iEp <= cEp; iEp++) {
-		extern char SzLimitScreenwriter[];
-		extern int BViewTVOriginal, BViewWatched;
+		extern char g_szLimitScreenwriter[];
+		extern int g_bViewTVOriginal, g_bViewWatched;
 
-		if (SzLimitScreenwriter[0])
+		if (g_szLimitScreenwriter[0])
 			if (!Pl("episode_data","episode_datum","ISS",
-				iEp,"Screenwriter",SzLimitScreenwriter))
+				iEp,"Screenwriter",g_szLimitScreenwriter))
 				continue;
 		
-		if (!BViewWatched)
+		if (!g_bViewWatched)
 			if (Pl("track_episodes","watched","I",iEp)) continue;
 
-		if (!BViewTVOriginal)
+		if (!g_bViewTVOriginal)
 			if (Pl("episode_data","tv_original","I",iEp)) continue;
 
 		/* Format episode number string. */
@@ -357,11 +311,11 @@ ElvUpdate()
 		lviEpisode.iSubItem = ELVSIEPISODE;
 		lviEpisode.pszText = tszEpisode;
 		lviEpisode.lParam = iEp;
-		ListView_InsertItem(HElv, &lviEpisode);
-		ElvUpdateItem(&lviEpisode);
+		ListView_InsertItem(m_hWnd, &lviEpisode);
+		UpdateItem(&lviEpisode);
 	}
 
-	ElvDoSort();
+	DoSort();
 
 	lvfi.flags = LVFI_PARAM;
 
@@ -369,12 +323,12 @@ ElvUpdate()
 	for (i = 0; aEpSel[i]; i++) {
 		int iItemSel;
 		lvfi.lParam = aEpSel[i];
-		if ((iItemSel = ListView_FindItem(HElv, -1, &lvfi)) != -1)
-			ListView_SetItemState(HElv, iItemSel,
+		if ((iItemSel = ListView_FindItem(m_hWnd, -1, &lvfi)) != -1)
+			ListView_SetItemState(m_hWnd, iItemSel,
 			    LVIS_SELECTED, LVIS_SELECTED);
 	}
 	if (iItemMark != -1)
-		ListView_SetSelectionMark(HElv, iItemMark);
+		ListView_SetSelectionMark(m_hWnd, iItemMark);
 
 	/* Reset focus. */
 	if (iEpFocus) {
@@ -382,10 +336,10 @@ ElvUpdate()
 		i = 0;
 		do
 			lvfi.lParam = iEpFocus+i;
-		while ((iItemFocus = ListView_FindItem(HElv, -1, &lvfi)) == -1
+		while ((iItemFocus = ListView_FindItem(m_hWnd, -1, &lvfi)) == -1
 		    && i++ < 100);
 		if (iItemFocus != -1)
-			ListView_SetItemState(HElv, iItemFocus,
+			ListView_SetItemState(m_hWnd, iItemFocus,
 			    LVIS_FOCUSED, LVIS_FOCUSED);
 	}
 
@@ -394,19 +348,19 @@ ElvUpdate()
 	i = 0;
 	do
 		lvfi.lParam = lviTop.lParam+i;
-	while ((iItemTopNew = ListView_FindItem(HElv, -1, &lvfi)) == -1
+	while ((iItemTopNew = ListView_FindItem(m_hWnd, -1, &lvfi)) == -1
 	    && i++ < 100);
 	if (iItemTopNew != -1)
-		ElvSetTop(iItemTopNew);
+		SetTop(iItemTopNew);
 
 	_stprintf_s(tszDisp, sizeof(tszDisp), TEXT("%d"), iItem);
-	SendMessage(HWndStatus, SB_SETTEXT, MAKEWPARAM(1,0), (LPARAM)tszDisp);
-	SendMessage(HElv, WM_SETREDRAW, TRUE, 0);
+	SendMessage(g_hWndStatus, SB_SETTEXT, MAKEWPARAM(1,0), (LPARAM)tszDisp);
+	SendMessage(m_hWnd, WM_SETREDRAW, TRUE, 0);
 }
 
 /* Update episode name and rating. */
 void
-ElvUpdateItem(LPLVITEM lpLvi)
+EpisodeListView::UpdateItem(LPLVITEM lpLvi)
 {
 	char *szName;
 	int iRating;
@@ -417,19 +371,90 @@ ElvUpdateItem(LPLVITEM lpLvi)
 	if (!Pl("episode_data","episode_title","Is",lpLvi->lParam,&szName)) {
 		if (!Pl("episode_data","update_episode_data","")) goto r;
 		if (!Pl("episode_data","episode_title","Is",lpLvi->lParam,&szName))
-		    goto r;
+			goto r;
 	}
 	tszName = TszFromSz(szName, CP_UTF8);
 	if (tszName)
-		ListView_SetItemText(HElv, lpLvi->iItem, ELVSITITLE, tszName);
+		ListView_SetItemText(m_hWnd, lpLvi->iItem, ELVSITITLE, tszName);
 
 r:	if (!Pl("episode_data","episode_rating","Ii",lpLvi->lParam,&iRating)) {
-		ListView_SetItemText(HElv, lpLvi->iItem, ELVSIRATING, TEXT(""));
+		ListView_SetItemText(m_hWnd, lpLvi->iItem, ELVSIRATING, TEXT(""));
 		goto f;
 	}
 
 	_stprintf_s(tszRating, sizeof(tszRating), TEXT("%d"), iRating);
-	ListView_SetItemText(HElv, lpLvi->iItem, ELVSIRATING, tszRating);
+	ListView_SetItemText(m_hWnd, lpLvi->iItem, ELVSIRATING, tszRating);
 
 f:	if (tszName) free(tszName);
 }
+
+/* Sort list view items, iSort being the 1-based index of the column
+ * to sort by. If iSort is negative, the order is descending. */
+int CALLBACK
+ElvSort(LPARAM iItem1, LPARAM iItem2, LPARAM iSort)
+{
+	int iOrder;
+	LVITEM lvi1, lvi2;
+	lvi1.mask = lvi2.mask = LVIF_PARAM;
+	lvi1.iItem = iItem1; lvi2.iItem = iItem2;
+	if (!ListView_GetItem(HSortLv, &lvi1)) return 0;
+	if (!ListView_GetItem(HSortLv, &lvi2)) return 0;
+	iOrder = Cmp(iSort, 0);
+	switch (abs(iSort)-1) {
+	case ELVSIEPISODE:
+		return iOrder*Cmp(lvi1.lParam, lvi2.lParam);
+		break;
+	case ELVSIRATING:
+	    {
+		int iRating1, iRating2;
+		iRating1 = iSort > 0? 99: -1;
+		iRating2 = iSort > 0? 99: -1;
+		Pl("episode_data","episode_rating","Ii",lvi1.lParam,&iRating1);
+		Pl("episode_data","episode_rating","Ii",lvi2.lParam,&iRating2);
+		if (iRating1 == iRating2)
+			return Cmp(lvi1.lParam, lvi2.lParam);
+		return iOrder*Cmp(iRating1, iRating2);
+		break;
+	    }
+	case ELVSITITLE:
+	    {
+		char *sz1, *sz2;
+		int cch, cch1, cch2;
+		if (!Pl("episode_data","episode_title","Is",lvi1.lParam,&sz1))
+			return 0;
+		if (!Pl("episode_data","episode_title","Is",lvi2.lParam,&sz2))
+			return 0;
+		cch1 = strlen(sz1);
+		cch2 = strlen(sz2);
+		cch = cch1 > cch2? cch2: cch1;
+		return iOrder*_strnicmp(sz1, sz2, cch);
+		break;
+	    }
+	default:
+		return 0;
+	}
+}
+
+LRESULT CALLBACK
+EpisodeListView::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+	switch (uMsg) {
+	case WM_GETDLGCODE:
+	    {
+		LRESULT lResult;
+
+		/* For the episode list view, the Enter key should not
+		 * be handled by the dialog manager, but instead be sent
+		 * along to the main window procedure, so that it may be
+		 * handled by the NM_RETURN case in ElvHandleNotify. */
+
+		lResult = CallWindowProc(m_prevProc, hWnd, uMsg, wParam, lParam);
+		if (lParam && ((MSG *)lParam)->message == WM_KEYDOWN
+		    && ((MSG *)lParam)->wParam == VK_RETURN)
+			return DLGC_WANTMESSAGE;
+		return lResult;
+	    }
+	}
+
+	return ListView::WndProc(hWnd, uMsg, wParam, lParam);
+}
diff --git a/c/listview.c b/c/listview.c
deleted file mode 100644
index 91838da..0000000
--- a/c/listview.c
+++ /dev/null
@@ -1,78 +0,0 @@
-#include <windows.h>
-#include <commctrl.h>
-#include <uxtheme.h>
-
-#include "resource.h"
-#include "defs.h"
-
-extern HFONT HfNormal;
-extern HWND HWnd;
-WNDPROC LvPrevProc;
-static LRESULT CALLBACK LvProc(HWND, UINT, WPARAM, LPARAM);
-
-HWND
-LvCreate(HMENU hMenu, DWORD dwStyle)
-{
-	HWND hLv;
-
-	hLv = CreateWindowEx(
-	    WS_EX_CLIENTEDGE,
-	    WC_LISTVIEW,
-	    TEXT(""),
-	    dwStyle|WS_CHILD|WS_VISIBLE|WS_VSCROLL|WS_TABSTOP
-	    |LVS_REPORT|LVS_SHOWSELALWAYS,
-	    0, 0, 0, 0,
-	    HWnd, hMenu, GetModuleHandle(NULL), NULL
-	);
-
-	LvPrevProc = (WNDPROC)SetWindowLongPtr(hLv,
-	    GWLP_WNDPROC, (LONG_PTR)LvProc);
-
-	ListView_SetExtendedListViewStyle(hLv, LVS_EX_FULLROWSELECT);
-
-	SendMessage(hLv, WM_SETFONT, (WPARAM)HfNormal, MAKELPARAM(FALSE, 0));
-
-	return hLv;
-}
-
-LRESULT CALLBACK
-LvProc(HWND hLv, UINT uMsg, WPARAM wParam, LPARAM lParam)
-{
-	switch (uMsg) {
-	case WM_NOTIFY:
-		switch (((LPNMHDR)lParam)->code) {
-		case HDN_ENDTRACK:
-			UpdateLayout();
-			return TRUE;
-		}
-		break;
-	case WM_GETDLGCODE:
-	    {
-		LRESULT lResult;
-		extern HWND HElv;
-
-		/* For the episode list view, the Enter key should not
-		 * be handled by the dialog manager, but instead be sent
-		 * along to the main window procedure, so that it may be
-		 * handled by the NM_RETURN case in ElvHandleNotify. */
-
-		if (hLv != HElv) break;
-		lResult = CallWindowProc(LvPrevProc, hLv, uMsg, wParam, lParam);
-		if (lParam && ((MSG *)lParam)->message == WM_KEYDOWN
-		    && ((MSG *)lParam)->wParam == VK_RETURN)
-			return DLGC_WANTMESSAGE;
-		return lResult;
-	    }
-	}
-
-	return CallWindowProc(LvPrevProc, hLv, uMsg, wParam, lParam);
-}
-
-/* Naively calculate height of list view. */
-int
-LvHeight(HWND hLv, int bHeader)
-{
-	int iCount;
-	iCount = ListView_GetItemCount(hLv);
-	return iCount? Dpi(bHeader? 27: 4)+iCount*Dpi(19): 0;
-}
diff --git a/c/listview.cpp b/c/listview.cpp
new file mode 100644
index 0000000..9f24dc3
--- /dev/null
+++ b/c/listview.cpp
@@ -0,0 +1,76 @@
+#include <windows.h>
+#include <commctrl.h>
+#include <uxtheme.h>
+
+#include "resource.h"
+#include "defs.h"
+
+extern HFONT g_hfNormal;
+extern HWND g_hWnd;
+static LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
+
+void
+ListView::Create(HMENU hMenu, DWORD dwStyle)
+{
+	m_hWnd = CreateWindowEx(
+	    WS_EX_CLIENTEDGE,
+	    WC_LISTVIEW,
+	    TEXT(""),
+	    dwStyle
+	    |WS_CHILD|WS_VISIBLE|WS_VSCROLL|WS_TABSTOP|LVS_REPORT|LVS_SHOWSELALWAYS,
+	    0, 0, 0, 0,
+	    g_hWnd, hMenu, GetModuleHandle(NULL), this
+	);
+
+	if (SetProp(m_hWnd, TEXT("this"), (HANDLE)this))
+		m_prevProc = (WNDPROC)SetWindowLongPtr(m_hWnd,
+		    GWLP_WNDPROC, (LONG_PTR)::WndProc);
+
+	ListView_SetExtendedListViewStyle(m_hWnd, LVS_EX_FULLROWSELECT);
+
+	SendMessage(m_hWnd, WM_SETFONT, (WPARAM)g_hfNormal, MAKELPARAM(FALSE, 0));
+}
+
+/* Naively calculate height of list view. */
+int
+ListView::Height(int bHeader)
+{
+	int iCount;
+	iCount = ListView_GetItemCount(m_hWnd);
+	return iCount? Dpi(bHeader? 27: 4)+iCount*Dpi(19): 0;
+}
+
+HWND
+ListView::HWnd()
+{
+	return m_hWnd;
+}
+
+LRESULT CALLBACK
+ListView::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+	switch (uMsg) {
+	case WM_NOTIFY:
+		switch (((LPNMHDR)lParam)->code) {
+		case HDN_ENDTRACK:
+			UpdateLayout();
+			return TRUE;
+		}
+		break;
+	}
+
+	return CallWindowProc(m_prevProc, hWnd, uMsg, wParam, lParam);
+}
+
+static LRESULT CALLBACK
+WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+	switch (uMsg) {
+	case WM_DESTROY:
+		RemoveProp(hWnd, TEXT("this"));
+		break;
+	}
+
+	ListView *lpThis = (ListView *)GetProp(hWnd, TEXT("this"));
+	return lpThis? lpThis->WndProc(hWnd, uMsg, wParam, lParam): FALSE;
+}
diff --git a/c/main.c b/c/main.cpp
index ef3877a..6799280 100644
--- a/c/main.c
+++ b/c/main.cpp
@@ -6,20 +6,23 @@
 #include "resource.h"
 #include "defs.h"
 
-atom_t AThread;
-char SzLimitScreenwriter[64] = {0};
-HFONT HfNormal;
-HFONT HfBold;
-HMENU HPopupMenu;
-HWND HFocus;
-HWND HWnd;
-HWND HWndStatus;
-int BViewTVOriginal = 1;
-int BViewWatched = 1;
-int BThread = 0;
-int IDPI = -1;
-static int BThemes;
-static int CxVScroll;
+EpisodeListView g_elv;
+DataListView g_dlv;
+
+atom_t g_aThread;
+char g_szLimitScreenwriter[64] = {0};
+HFONT g_hfNormal;
+HFONT g_fBold;
+HMENU g_hPopupMenu;
+HWND g_hFocus;
+HWND g_hWnd;
+HWND g_hWndStatus;
+int g_bViewTVOriginal = 1;
+int g_bViewWatched = 1;
+int g_bThread = 0;
+int g_iDPI = -1;
+static int g_bThemes;
+static int g_cxVScroll;
 static LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 static INT_PTR CALLBACK AboutDlgProc(HWND, UINT, WPARAM, LPARAM);
 static HWND CreateStatusBar(HWND, HINSTANCE);
@@ -41,12 +44,12 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
 
 	/* Set constant values. */
 	hModule = LoadLibrary(TEXT("uxtheme.dll"));
-	BThemes = hModule && GetProcAddress(hModule,"SetWindowTheme");
+	g_bThemes = hModule && GetProcAddress(hModule,"SetWindowTheme");
 	if (hModule) FreeLibrary(hModule);
-	CxVScroll = GetSystemMetrics(SM_CXVSCROLL);
+	g_cxVScroll = GetSystemMetrics(SM_CXVSCROLL);
 
 	/* Initialize Prolog. */
-	argv[0] = "EpisodeBrowser";
+	argv[0] = (char *)"EpisodeBrowser";
 	argv[1] = NULL;
 	tszErr = TEXT("Could not initialize Prolog.");
 	if (!PL_initialise(1, argv)) goto f;
@@ -59,8 +62,8 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
 	tszErr = TEXT("Could not initialize common controls.");
 	if (!InitCommonControlsEx(&icc)) goto f;
 
-	HPopupMenu = LoadMenu(NULL, MAKEINTRESOURCE(IDR_POPUPMENU));
-	HPopupMenu = GetSubMenu(HPopupMenu, 0);
+	g_hPopupMenu = LoadMenu(NULL, MAKEINTRESOURCE(IDR_POPUPMENU));
+	g_hPopupMenu = GetSubMenu(g_hPopupMenu, 0);
 
 	memset(&wc, 0, sizeof(WNDCLASSEX));
 	wc.cbSize	 = sizeof(WNDCLASSEX);
@@ -86,13 +89,13 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
 	);
 	tszErr = TEXT("Could not create main window.");
 	if (!hWnd) goto f;
-	HWndStatus = CreateStatusBar(hWnd, hInstance);
+	g_hWndStatus = CreateStatusBar(hWnd, hInstance);
 	ShowWindow(hWnd, nCmdShow);
 
 	/* Populate episode list view. */
 	Pl("track_episodes", "update_tracked_episodes", "");
-	ElvUpdate();
-	ElvSelectFocus();
+	g_elv.Update();
+	g_elv.SelectFocus();
 
 	while (GetMessage(&msg, NULL, 0, 0) > 0) {
 		if (IsDialogMessage(hWnd, &msg)) continue;
@@ -114,36 +117,35 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 	case WM_CREATE:
 	    {
 		HMODULE hModule;
-		FARPROC GetDpiForWindow;
-		extern HWND HWnd, HElv;
-		HWnd = hWnd;
-		IDPI = 96;
+		UINT (*GetDpiForWindow)(HWND);
+		g_hWnd = hWnd;
+		g_iDPI = 96;
 		hModule = LoadLibrary(TEXT("User32.dll"));
-		if (hModule && (GetDpiForWindow = GetProcAddress(hModule, "GetDpiForWindow"))) {
-			IDPI = GetDpiForWindow(HWnd);
+		if (hModule && (GetDpiForWindow = (UINT (*)(HWND))GetProcAddress(hModule, "GetDpiForWindow"))) {
+			g_iDPI = GetDpiForWindow(g_hWnd);
 			FreeLibrary(hModule);
 		}
 		SetWindowPos(hWnd, NULL, -1, -1, Dpi(510), Dpi(400), SWP_NOMOVE);
-		if (Pl("cfg","get_view_watched","i",&BViewWatched))
+		if (Pl("cfg","get_view_watched","i",&g_bViewWatched))
 			CheckMenuItem(GetMenu(hWnd), IDM_VIEW_WATCHED,
-			    BViewWatched? MF_CHECKED: MF_UNCHECKED);
-		if (Pl("cfg","get_view_tv_original","i",&BViewTVOriginal))
+			    g_bViewWatched? MF_CHECKED: MF_UNCHECKED);
+		if (Pl("cfg","get_view_tv_original","i",&g_bViewTVOriginal))
 			CheckMenuItem(GetMenu(hWnd), IDM_VIEW_TV_ORIGINAL,
-			    BViewTVOriginal? MF_CHECKED: MF_UNCHECKED);
+			    g_bViewTVOriginal? MF_CHECKED: MF_UNCHECKED);
 		{
 			char *sz;
 			if (!Pl("cfg","get_limit_screenwriter","s",&sz))
 				goto s;
-			strcpy_s(SzLimitScreenwriter,
-			    sizeof(SzLimitScreenwriter), sz);
+			strcpy_s(g_szLimitScreenwriter,
+			    sizeof(g_szLimitScreenwriter), sz);
 			CheckMenuItem(GetMenu(hWnd), IDM_VIEW_OTHERS,
-			    SzLimitScreenwriter[0]? MF_UNCHECKED: MF_CHECKED);
+			    g_szLimitScreenwriter[0]? MF_UNCHECKED: MF_CHECKED);
 		}
 	    s:	SetupFonts();
-		DlvCreate();
-		ElvCreate();
+		g_dlv.Create();
+		g_elv.Create();
 		UpdateTheme();
-		SetFocus(HElv);
+		SetFocus(g_elv.HWnd());
 		break;
 	    }
 	case WM_CLOSE:
@@ -152,23 +154,23 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 	case WM_DESTROY:
 	    {
 		LVITEM lvi;
-		extern HWND HElv;
+		HWND hElv;
+		hElv = g_elv.HWnd();
 		lvi.mask = LVIF_PARAM;
-		if ((lvi.iItem=ListView_GetNextItem(HElv,-1,LVNI_FOCUSED)) != -1
-		    && ListView_GetItem(HElv, &lvi))
+		if ((lvi.iItem=ListView_GetNextItem(hElv,-1,LVNI_FOCUSED)) != -1
+		    && ListView_GetItem(hElv, &lvi))
 			Pl("cfg","set_focus","I",lvi.lParam);
 		PostQuitMessage(0);
 		break;
 	    }
 	case WM_SIZE:
-		SendMessage(HWndStatus, WM_SIZE, wParam, lParam);
+		SendMessage(g_hWndStatus, WM_SIZE, wParam, lParam);
 		UpdateLayout();
 		break;
 	case WM_GETMINMAXINFO:
 	    {
 		LPMINMAXINFO lpMMI = (LPMINMAXINFO)lParam;
-		extern HWND HDlv;
-		lpMMI->ptMinTrackSize.y = LvHeight(HDlv, 0)+80;
+		lpMMI->ptMinTrackSize.y = g_dlv.Height(0)+80;
 		break;
 	    }
 	case WM_THEMECHANGED:
@@ -178,7 +180,7 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 	    {
 		LPRECT lpr;
 		lpr = (LPRECT)lParam;
-		IDPI = HIWORD(wParam);
+		g_iDPI = HIWORD(wParam);
 		SetWindowPos(hWnd, NULL,
 		    lpr->left, lpr->top,
 		    lpr->right-lpr->left,
@@ -190,19 +192,19 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 	case WM_ACTIVATE:
 		switch (wParam) {
 		case WA_INACTIVE:
-			HFocus = GetFocus();
+			g_hFocus = GetFocus();
 			break;
 		case WA_ACTIVE:
 		case WA_CLICKACTIVE:
-			SetFocus(HFocus);
+			SetFocus(g_hFocus);
 			Pl("track_episodes","update_tracked_episodes","");
-			ElvRedraw();
+			g_elv.Redraw();
 		}
 		break;
 	case WM_NOTIFY:
 		switch (((LPNMHDR)lParam)->idFrom) {
 		case IDC_EPISODELISTVIEW:
-			return ElvHandleNotify(lParam);
+			return g_elv.HandleNotify(lParam);
 		}
 		break;
 	case WM_TIMER:
@@ -210,9 +212,9 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 		case IDT_TIMER:
 		    {
 			static int i = 0;
-			if (Pl("episode_data","thread_running","A",AThread)) {
+			if (Pl("episode_data","thread_running","A",g_aThread)) {
 				i = (i+1)%4;
-				SendMessage(HWndStatus, SB_SETTEXT, MAKEWPARAM(1,0),
+				SendMessage(g_hWndStatus, SB_SETTEXT, MAKEWPARAM(1,0),
 				    (LPARAM)(i==0? TEXT("."):
 					i==1? TEXT(".."):
 					i==2? TEXT("..."):
@@ -220,7 +222,7 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			} else {
 				i = 0;
 				KillTimer(hWnd, IDT_TIMER);
-				ElvUpdate();
+				g_elv.Update();
 			}
 			break;
 		    }
@@ -232,19 +234,19 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			PostMessage(hWnd, WM_CLOSE, 0, 0);
 			break;
 		case IDM_FILE_REFRESH:
-			ElvUpdate();
+			g_elv.Update();
 			break;
 		case IDM_FILE_FETCH_DATA:
-			if (BThread) break;
-			Pl("episode_data","thread_create","Sa","update_episode_data",&AThread);
+			if (g_bThread) break;
+			Pl("episode_data","thread_create","Sa","update_episode_data",&g_aThread);
 			goto t;
 		case IDM_FILE_FETCH_SCREENWRITERS:
-			if (BThread) break;
-			Pl("episode_data","thread_create","Sa","update_screenwriters",&AThread);
+			if (g_bThread) break;
+			Pl("episode_data","thread_create","Sa","update_screenwriters",&g_aThread);
 		t:	KillTimer(hWnd, IDT_TIMER);
 			SetTimer(hWnd, IDT_TIMER, 500, NULL);
-			SendMessage(HWndStatus, SB_SETTEXT, MAKEWPARAM(1,0), (LPARAM)TEXT("."));
-			BThread = 1;
+			SendMessage(g_hWndStatus, SB_SETTEXT, MAKEWPARAM(1,0), (LPARAM)TEXT("."));
+			g_bThread = 1;
 			break;
 		case IDM_FILE_ABOUT:
 			DialogBox(
@@ -257,61 +259,64 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 		case IDM_VIEW_WATCHED:
 		    {
 			int iEpFocus;
-			extern HWND HElv;
+			HWND hElv;
+			hElv = g_elv.HWnd();
 			CheckMenuItem(GetMenu(hWnd), IDM_VIEW_WATCHED,
-			    BViewWatched? MF_UNCHECKED: MF_CHECKED);
-			BViewWatched = !BViewWatched;
-			ElvUpdate();
-			Pl("cfg","set_view_watched","I",BViewWatched);
-			iEpFocus = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED);
+			    g_bViewWatched? MF_UNCHECKED: MF_CHECKED);
+			g_bViewWatched = !g_bViewWatched;
+			g_elv.Update();
+			Pl("cfg","set_view_watched","I",g_bViewWatched);
+			iEpFocus = ListView_GetNextItem(hElv, -1, LVNI_FOCUSED);
 			if (iEpFocus == -1) break;
-			ListView_EnsureVisible(HElv, iEpFocus, TRUE);
+			ListView_EnsureVisible(hElv, iEpFocus, TRUE);
 			break;
 		    }
 		case IDM_VIEW_TV_ORIGINAL:
 		    {
 			int iEpFocus;
-			extern HWND HElv;
+			HWND hElv;
+			hElv = g_elv.HWnd();
 			CheckMenuItem(GetMenu(hWnd), IDM_VIEW_TV_ORIGINAL,
-			    BViewTVOriginal? MF_UNCHECKED: MF_CHECKED);
-			BViewTVOriginal = !BViewTVOriginal;
-			ElvUpdate();
-			Pl("cfg","set_view_tv_original","I",BViewTVOriginal);
-			iEpFocus = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED);
+			    g_bViewTVOriginal? MF_UNCHECKED: MF_CHECKED);
+			g_bViewTVOriginal = !g_bViewTVOriginal;
+			g_elv.Update();
+			Pl("cfg","set_view_tv_original","I",g_bViewTVOriginal);
+			iEpFocus = ListView_GetNextItem(hElv, -1, LVNI_FOCUSED);
 			if (iEpFocus == -1) break;
-			ListView_EnsureVisible(HElv, iEpFocus, TRUE);
+			ListView_EnsureVisible(hElv, iEpFocus, TRUE);
 			break;
 		    }
 		case IDM_VIEW_OTHERS:	/* Show/hide other screenwriters. */
 		    {
 			int iEpFocus;
-			extern HWND HElv;
-			if (SzLimitScreenwriter[0]) {
+			HWND hElv;
+			hElv = g_elv.HWnd();
+			if (g_szLimitScreenwriter[0]) {
 				CheckMenuItem(GetMenu(hWnd), IDM_VIEW_OTHERS,
 				    MF_CHECKED);
-				SzLimitScreenwriter[0] = 0;
+				g_szLimitScreenwriter[0] = 0;
 			} else {
 				char *sz;
 				LVITEM lvi;
-				iEpFocus = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED);
+				iEpFocus = ListView_GetNextItem(hElv, -1, LVNI_FOCUSED);
 				if (iEpFocus == -1) break;
 				lvi.iItem = iEpFocus;
 				lvi.mask = LVIF_PARAM;
-				if (!ListView_GetItem(HElv, &lvi)) break;
+				if (!ListView_GetItem(hElv, &lvi)) break;
 				if (!Pl("episode_data","episode_datum","ISs",
 					lvi.lParam,"Screenwriter",&sz))
 					break;
-				strcpy_s(SzLimitScreenwriter,
-				    sizeof(SzLimitScreenwriter), sz);
+				strcpy_s(g_szLimitScreenwriter,
+				    sizeof(g_szLimitScreenwriter), sz);
 				CheckMenuItem(GetMenu(hWnd), IDM_VIEW_OTHERS,
 				    MF_UNCHECKED);
 			}
-			ElvUpdate();
+			g_elv.Update();
 			Pl("cfg","set_limit_screenwriter","S",
-			    SzLimitScreenwriter);
-			iEpFocus = ListView_GetNextItem(HElv, -1, LVNI_FOCUSED);
+			    g_szLimitScreenwriter);
+			iEpFocus = ListView_GetNextItem(hElv, -1, LVNI_FOCUSED);
 			if (iEpFocus == -1) break;
-			ListView_EnsureVisible(HElv, iEpFocus, TRUE);
+			ListView_EnsureVisible(hElv, iEpFocus, TRUE);
 			break;
 		    }
 		case IDM_WATCH_LOCALLY:
@@ -334,7 +339,8 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 		    {
 			int iRating;
 			LVITEM lvi;
-			extern HWND HElv;
+			HWND hElv;
+			hElv = g_elv.HWnd();
 
 			/* Look through selected items, applying the
 			 * selected command to each one. */
@@ -342,8 +348,8 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			lvi.mask = LVIF_PARAM;
 			lvi.iItem = -1;
 			while ((lvi.iItem = ListView_GetNextItem(
-				    HElv, lvi.iItem, LVNI_SELECTED)) != -1) {
-				if (!ListView_GetItem(HElv, &lvi)) goto b;
+				    hElv, lvi.iItem, LVNI_SELECTED)) != -1) {
+				if (!ListView_GetItem(hElv, &lvi)) goto b;
 
 				switch (LOWORD(wParam)) {
 				case IDM_WATCH_LOCALLY:
@@ -354,18 +360,18 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 					break;
 				case IDM_TOGGLE:
 					Pl("track_episodes","toggle_episode","I",lvi.lParam);
-					ElvRedraw();
+					g_elv.Redraw();
 					break;
 				case IDM_FORGET:
 					Pl("track_episodes","forget_episode","I",lvi.lParam);
 					Pl("track_episodes","update_tracked_episodes","");
-					ElvRedraw();
+					g_elv.Redraw();
 					break;
 				case IDM_LOOKUP:
 					Pl("episode_data","retract_episode","I",lvi.lParam);
-					ElvUpdateItem(&lvi);
-					ElvRedraw();
-					DlvShowEpisode(lvi.lParam);
+					g_elv.UpdateItem(&lvi);
+					g_elv.Redraw();
+					g_dlv.ShowEpisode(lvi.lParam);
 					break;
 				case IDM_WIKI:
 					Pl("episode_data","open_episode_wiki","I",lvi.lParam);
@@ -403,7 +409,7 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 				case IDM_RATE0:
 					iRating = 0;
 				r:	Pl("episode_data","rate_episode","II",lvi.lParam,iRating);
-					ElvUpdateItem(&lvi);
+					g_elv.UpdateItem(&lvi);
 					break;
 				}
 			}
@@ -419,9 +425,9 @@ WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			case IDM_RATE2:
 			case IDM_RATE1:
 			case IDM_RATE0:
-				ElvRedraw();
-				ElvDoSort();
-				ElvShowFocus();
+				g_elv.Redraw();
+				g_elv.DoSort();
+				g_elv.ShowFocus();
 			}
 		    b:	break;
 		    }
@@ -496,14 +502,14 @@ SetupFonts()
 		m.cbSize = sizeof(NONCLIENTMETRICS);
 		SystemParametersInfo(SPI_GETNONCLIENTMETRICS,
 		    sizeof(NONCLIENTMETRICS), &m, 0);
-		HfNormal = CreateFontIndirect(&m.lfMessageFont);
+		g_hfNormal = CreateFontIndirect(&m.lfMessageFont);
 		FreeLibrary(hModule);
 	} else
-		HfNormal = GetStockObject(DEFAULT_GUI_FONT);
+		g_hfNormal = static_cast<HFONT>(GetStockObject(DEFAULT_GUI_FONT));
 
-	GetObject(HfNormal, sizeof(LOGFONT), &lf);
+	GetObject(g_hfNormal, sizeof(LOGFONT), &lf);
 	lf.lfWeight = FW_BOLD;
-	HfBold = CreateFontIndirect(&lf);
+	g_fBold = CreateFontIndirect(&lf);
 }
 
 /***/
@@ -513,36 +519,39 @@ UpdateLayout()
 {
 	int cxColumn, cyDlv, yStatus;
 	RECT rc, rcStatus;
-	extern HWND HDlv, HElv;
+	HWND hDlv, hElv;
 
-	GetClientRect(HWnd, &rc);
-	GetClientRect(HWndStatus, &rcStatus);
+	hDlv = g_dlv.HWnd();
+	hElv = g_elv.HWnd();
+
+	GetClientRect(g_hWnd, &rc);
+	GetClientRect(g_hWndStatus, &rcStatus);
 	yStatus = rcStatus.bottom-rcStatus.top;
 
 	/* Resize data list view. */
-	SendMessage(HDlv, WM_SETREDRAW, FALSE, 0);
-	SendMessage(HElv, WM_SETREDRAW, FALSE, 0);
-	cyDlv = rc.bottom-yStatus-LvHeight(HDlv, DLVSIKEY);
-	MoveWindow(HDlv, 0, cyDlv, rc.right, rc.bottom-yStatus-cyDlv, TRUE);
-	ListView_SetColumnWidth(HDlv, DLVSIKEY, LVSCW_AUTOSIZE);
-	cxColumn = ListView_GetColumnWidth(HDlv, 0)+4;
-	ListView_SetColumnWidth(HDlv, DLVSIKEY, cxColumn);
-	ListView_SetColumnWidth(HDlv, DLVSIVALUE, rc.right-cxColumn-CxVScroll-4);
+	SendMessage(hDlv, WM_SETREDRAW, FALSE, 0);
+	SendMessage(hElv, WM_SETREDRAW, FALSE, 0);
+	cyDlv = rc.bottom-yStatus-g_dlv.Height(DLVSIKEY);
+	MoveWindow(hDlv, 0, cyDlv, rc.right, rc.bottom-yStatus-cyDlv, TRUE);
+	ListView_SetColumnWidth(hDlv, DLVSIKEY, LVSCW_AUTOSIZE);
+	cxColumn = ListView_GetColumnWidth(hDlv, 0)+4;
+	ListView_SetColumnWidth(hDlv, DLVSIKEY, cxColumn);
+	ListView_SetColumnWidth(hDlv, DLVSIVALUE, rc.right-cxColumn-g_cxVScroll-4);
 
 	/* Resize episode list view. */
-	MoveWindow(HElv, 0, 0, rc.right, cyDlv+1, TRUE);
-	ListView_SetColumnWidth(HElv, ELVSIEPISODE, LVSCW_AUTOSIZE);
-	cxColumn = ListView_GetColumnWidth(HElv, ELVSIEPISODE)+4;
-	ListView_SetColumnWidth(HElv, ELVSIEPISODE, cxColumn);
-	cxColumn += ListView_GetColumnWidth(HElv, ELVSIRATING);
-	ListView_SetColumnWidth(HElv, ELVSITITLE, rc.right-cxColumn-CxVScroll-4);
-	SendMessage(HElv, WM_SETREDRAW, TRUE, 0);
-	SendMessage(HDlv, WM_SETREDRAW, TRUE, 0);
+	MoveWindow(hElv, 0, 0, rc.right, cyDlv+1, TRUE);
+	ListView_SetColumnWidth(hElv, ELVSIEPISODE, LVSCW_AUTOSIZE);
+	cxColumn = ListView_GetColumnWidth(hElv, ELVSIEPISODE)+4;
+	ListView_SetColumnWidth(hElv, ELVSIEPISODE, cxColumn);
+	cxColumn += ListView_GetColumnWidth(hElv, ELVSIRATING);
+	ListView_SetColumnWidth(hElv, ELVSITITLE, rc.right-cxColumn-g_cxVScroll-4);
+	SendMessage(hElv, WM_SETREDRAW, TRUE, 0);
+	SendMessage(hDlv, WM_SETREDRAW, TRUE, 0);
 
 	/* Resize status bar parts. */
 	{
 		int aParts[] = {rc.right-Dpi(55), rc.right};
-		SendMessage(HWndStatus, SB_SETPARTS,
+		SendMessage(g_hWndStatus, SB_SETPARTS,
 		    (WPARAM)sizeof(aParts), (LPARAM)aParts);
 	}
 }
@@ -554,9 +563,12 @@ UpdateTheme()
 	DWORD dwStyle;
 	LPTSTR tszTheme;
 	WORD wAction;
-	extern HWND HElv, HDlv;
+	HWND hDlv, hElv;
+
+	hDlv = g_dlv.HWnd();
+	hElv = g_elv.HWnd();
 
-	if (!BThemes) return;
+	if (!g_bThemes) return;
 	if (IsThemeActive()) {
 		dwStyle = LVS_EX_DOUBLEBUFFER;
 		tszTheme = TEXT("Explorer");
@@ -568,14 +580,14 @@ UpdateTheme()
 	}
 
 	/* Use modern "Explorer" theme. */
-	SetWindowTheme(HElv, tszTheme, NULL);
-	SetWindowTheme(HDlv, tszTheme, NULL);
+	SetWindowTheme(hElv, tszTheme, NULL);
+	SetWindowTheme(hDlv, tszTheme, NULL);
 
 	/* The modern theme requires double buffering. */
-	ListView_SetExtendedListViewStyleEx(HElv, LVS_EX_DOUBLEBUFFER, dwStyle);
-	ListView_SetExtendedListViewStyleEx(HDlv, LVS_EX_DOUBLEBUFFER, dwStyle);
+	ListView_SetExtendedListViewStyleEx(hElv, LVS_EX_DOUBLEBUFFER, dwStyle);
+	ListView_SetExtendedListViewStyleEx(hDlv, LVS_EX_DOUBLEBUFFER, dwStyle);
 
 	/* Hide focus rectangles. */
-	SendMessage(HElv, WM_UPDATEUISTATE, MAKEWPARAM(wAction, UISF_HIDEFOCUS), 0);
-	SendMessage(HDlv, WM_UPDATEUISTATE, MAKEWPARAM(wAction, UISF_HIDEFOCUS), 0);
+	SendMessage(hElv, WM_UPDATEUISTATE, MAKEWPARAM(wAction, UISF_HIDEFOCUS), 0);
+	SendMessage(hDlv, WM_UPDATEUISTATE, MAKEWPARAM(wAction, UISF_HIDEFOCUS), 0);
 }
diff --git a/c/pl.c b/c/pl.cpp
index 50f5429..dd69517 100644
--- a/c/pl.c
+++ b/c/pl.cpp
@@ -3,12 +3,12 @@
 #include <SWI-Prolog.h>
 #include "defs.h"
 
-static int Plpv(term_t, char *, va_list);
-static int Plgv(term_t, char *, va_list);
+static int Plpv(term_t, const char *, va_list);
+static int Plgv(term_t, const char *, va_list);
 
 /* Call Prolog predicate once. */
 int
-Pl(char *szMod, char *szPred, char *szFmt, ...)
+Pl(const char *szMod, const char *szPred, const char *szFmt, ...)
 {
 	int iArity;
 	term_t t;
@@ -36,7 +36,7 @@ f:	va_end(vl);
 
 /* Put known values in term. */
 int
-Plp(term_t t, char *szFmt, ...)
+Plp(term_t t, const char *szFmt, ...)
 {
 	int r;
 	va_list vl;
@@ -46,7 +46,7 @@ Plp(term_t t, char *szFmt, ...)
 	return r;
 }
 int
-Plpv(term_t t, char *szFmt, va_list vl)
+Plpv(term_t t, const char *szFmt, va_list vl)
 {
 	int i;
 	for (i = 0; szFmt[i]; i++) {
@@ -90,7 +90,7 @@ Plpv(term_t t, char *szFmt, va_list vl)
 
 /* Get unknown values from term. */
 int
-Plg(term_t t, char *szFmt, ...)
+Plg(term_t t, const char *szFmt, ...)
 {
 	int r;
 	va_list vl;
@@ -100,7 +100,7 @@ Plg(term_t t, char *szFmt, ...)
 	return r;
 }
 int
-Plgv(term_t t, char *szFmt, va_list vl)
+Plgv(term_t t, const char *szFmt, va_list vl)
 {
 	int i;
 	for (i = 0; szFmt[i]; i++) {