static HTREEITEM TreeItemForPageNo(WindowInfo *win, HTREEITEM hItem, int pageNo)
{
HTREEITEM hCurrItem = nullptr;
while (hItem) {
TVITEM item;
item.hItem = hItem;
item.mask = TVIF_PARAM | TVIF_STATE;
item.stateMask = TVIS_EXPANDED;
TreeView_GetItem(win->hwndTocTree, &item);
// return if this item is on the specified page (or on a latter page)
if (item.lParam) {
int page = ((DocTocItem *)item.lParam)->pageNo;
if (1 <= page && page <= pageNo)
hCurrItem = hItem;
if (page >= pageNo)
break;
}
// find any child item closer to the specified page
HTREEITEM hSubItem = nullptr;
if ((item.state & TVIS_EXPANDED))
hSubItem = TreeItemForPageNo(win, TreeView_GetChild(win->hwndTocTree, hItem), pageNo);
if (hSubItem)
hCurrItem = hSubItem;
hItem = TreeView_GetNextSibling(win->hwndTocTree, hItem);
}
return hCurrItem;
}
void UpdateTocSelection(WindowInfo *win, int currPageNo)
{
if (!win->tocLoaded || !win->tocVisible || win->tocKeepSelection)
return;
HTREEITEM hRoot = TreeView_GetRoot(win->hwndTocTree);
if (!hRoot)
return;
// select the item closest to but not after the current page
// (or the root item, if there's no such item)
HTREEITEM hItem = TreeItemForPageNo(win, hRoot, currPageNo);
TreeView_SelectItem(win->hwndTocTree, hItem);
}
