Add new setsize api to widget and better size support for list

This adds a distinction between the list size (list.sz) and the list's
frame size (list.frame.sz). This commit also adds the widget::setsize
api and implements it for list.

2 files changed, 65 insertions, 34 deletions

diff --git a/libtui/widget/list/list.ha b/libtui/widget/list/list.ha
index a897bb8..070e4f7 100644
--- a/libtui/widget/list/list.ha
+++ b/libtui/widget/list/list.ha
@@ -29,6 +29,7 @@ export type frame = struct {
 	start: u16,
 	// largest value is nb of items
 	end: u16,
+	sz: ttysize,
 };
 
 export type ttysize = struct {
@@ -46,9 +47,16 @@ export type listener = *fn(l: *listwidget, r: (rune | libtui::specialkey)) bool;
 // using [[strings::dupall]]], so the original items can be freed.
 export fn newlist(ui: libtui::ttyui, items: str...) listwidget = {
 	let sz = libtui::getwinsize(ui)!;
-	//let rows = sz.rows - 1;
-	let rows: (u16 | size) = if (sz.rows - 1 < len(items)) {
-		yield sz.rows - 1;
+	return newlistsz(ui, sz, items...);
+};
+
+// Create a new list with the given items and size. The given items will be
+// duplicated using [[strings::dupall]]], so the original items can be freed.
+export fn newlistsz(ui: libtui::ttyui, sz: tty::ttysize, items: str...) listwidget = {
+	//let sz = libtui::getwinsize(ui)!;
+	let rows = sz.rows;
+	let rows: (u16 | size) = if (sz.rows < len(items)) {
+		yield sz.rows;
 	} else {
 		yield len(items);
 	};
@@ -66,9 +74,13 @@ export fn newlist(ui: libtui::ttyui, items: str...) listwidget = {
 		frame = frame {
 			start = 0u16,
 			end = rows: u16,
+			sz = ttysize {
+				rows = rows: u16,
+				cols = sz.columns,
+			},
 		},
 		sz = ttysize {
-			rows = rows: u16,
+			rows = sz.rows,
 			cols = sz.columns,
 		},
 	};
@@ -128,22 +140,22 @@ export fn print(list: *widget::widget) (void | widget::error) = {
 
 	let st = strio::dynamic();
 	strio::concat(&st, "\r")?;
-	let end = if (list.frame.end < len(list.items)) {
-		yield list.frame.end;
-	} else {
-		yield len(list.items);
-	};
-	for (let i = list.frame.start; i < end: u16; i += 1) {
-		const item = list.items[i];
-		const truncitem = wcwidth::truncate(item, list.sz.cols);
-		if (list.cursor == i) {
-			strio::concat(&st, SELECTED, truncitem, RESET)?;
-			//libtui::print(list.ui, strings::concat("\x1B[31;1m> ", list.items[i], "\x1B[0m"));
-		} else if (set::contains(&list.marked, i)) {
-			strio::concat(&st, MARKED, truncitem, RESET)?;
-			//libtui::print(list.ui, list.items[i]);
-		} else {
-			strio::concat(&st, truncitem)?;
+
+	let end = list.frame.start + list.sz.rows;
+
+	for (let i = list.frame.start; i < end; i += 1) {
+		if (i < len(list.items)) {
+			const item = list.items[i];
+			const truncitem = wcwidth::truncate(item, list.sz.cols);
+			if (list.cursor == i) {
+				strio::concat(&st, SELECTED, truncitem, RESET)?;
+				//libtui::print(list.ui, strings::concat("\x1B[31;1m> ", list.items[i], "\x1B[0m"));
+			} else if (set::contains(&list.marked, i)) {
+				strio::concat(&st, MARKED, truncitem, RESET)?;
+				//libtui::print(list.ui, list.items[i]);
+			} else {
+				strio::concat(&st, truncitem)?;
+			};
 		};
 		strio::concat(&st, "\r\n")?;
 	};
@@ -171,7 +183,7 @@ export fn reframe(l: *listwidget) bool = {
 	let reframed: bool = false;
 	if (l.cursor < l.frame.start) {
 		l.frame.start = l.cursor: u16;
-		l.frame.end = l.frame.start + l.sz.rows;
+		l.frame.end = l.frame.start + l.frame.sz.rows;
 		//l.frame.end -= l.frame.start - l.cursor: u16;
 		reframed = true;
 	};
@@ -186,24 +198,24 @@ export fn reframe(l: *listwidget) bool = {
 // Use signalfd and [[unix::signal::SIGWINCH]] and call this function in the
 // handler to support resizing the list.
 export fn resize(l: *listwidget, oldsz: ttysize) bool = {
-	if (l.frame.end - l.frame.start != l.sz.rows) {
+	if (l.frame.end - l.frame.start != l.frame.sz.rows) {
 		if (l.cursor < (l.frame.end / 2)) {
-			l.frame.end = if (l.frame.start + l.sz.rows > len(l.items)) {
-				l.frame.start = len(l.items): u16 - l.sz.rows;
+			l.frame.end = if (l.frame.start + l.frame.sz.rows > len(l.items)) {
+				l.frame.start = len(l.items): u16 - l.frame.sz.rows;
 				yield len(l.items): u16;
 			} else {
-				yield l.frame.start + l.sz.rows;
+				yield l.frame.start + l.frame.sz.rows;
 			};
 			for (l.cursor > l.frame.end) {
 				l.frame.start += 1;
 				l.frame.end += 1;
 			};
 		} else {
-			l.frame.start = if (l.frame.end: int - l.sz.rows: int < 0) {
-				l.frame.end = 0 + l.sz.rows;
+			l.frame.start = if (l.frame.end: int - l.frame.sz.rows: int < 0) {
+				l.frame.end = 0 + l.frame.sz.rows;
 				yield 0;
 			} else {
-				yield l.frame.end - l.sz.rows;
+				yield l.frame.end - l.frame.sz.rows;
 			};
 			for (l.cursor < l.frame.start) {
 				l.frame.start -= 1;
@@ -215,6 +227,22 @@ export fn resize(l: *listwidget, oldsz: ttysize) bool = {
 	return false;
 };
 
+export fn setsize(l: *listwidget, sz: tty::ttysize) void = {
+	let rows: (u16 | size) = if (sz.rows < len(l.items)) {
+		yield sz.rows;
+	} else {
+		yield len(l.items);
+	};
+	l.sz = ttysize {
+		rows = sz.rows,
+		cols = sz.columns,
+	};
+	l.frame.sz = ttysize {
+		rows = rows: u16,
+		cols = sz.columns,
+	};
+};
+
 fn cursorinframe(l: *listwidget) bool = {
 	return l.cursor >= l.frame.start && l.cursor < l.frame.end;
 };
@@ -239,8 +267,8 @@ export fn up(l: *listwidget) size = {
 
 // Move the list's cursor up one page. Returns the new cursor.
 export fn pageup(l: *listwidget) size = {
-	if (l.cursor: int - l.sz.rows: int >= 0) {
-		l.cursor -= l.sz.rows;
+	if (l.cursor: int - l.frame.sz.rows: int >= 0) {
+		l.cursor -= l.frame.sz.rows;
 	} else {
 		l.cursor = 0z;
 	};
@@ -250,8 +278,8 @@ export fn pageup(l: *listwidget) size = {
 
 // Move the list's cursor down one page. Returns the new cursor.
 export fn pagedown(l: *listwidget) size = {
-	if (l.cursor + l.sz.rows < len(l.items)) {
-		l.cursor += l.sz.rows;
+	if (l.cursor + l.frame.sz.rows < len(l.items)) {
+		l.cursor += l.frame.sz.rows;
 	} else {
 		l.cursor = len(l.items) - 1;
 	};
@@ -263,7 +291,7 @@ export fn pagedown(l: *listwidget) size = {
 export fn top(l: *listwidget) size = {
 	l.cursor = 0;
 	l.frame.start = 0;
-	l.frame.end = l.frame.start + l.sz.rows;
+	l.frame.end = l.frame.start + l.frame.sz.rows;
 	return l.cursor;
 };
 
@@ -271,7 +299,7 @@ export fn top(l: *listwidget) size = {
 export fn bottom(l: *listwidget) size = {
 	l.cursor = len(l.items) - 1;
 	l.frame.end = len(l.items): u16;
-	l.frame.start = l.frame.end - l.sz.rows;
+	l.frame.start = l.frame.end - l.frame.sz.rows;
 	return l.cursor;
 };
 
diff --git a/libtui/widget/widget.ha b/libtui/widget/widget.ha
index 6875692..307378d 100644
--- a/libtui/widget/widget.ha
+++ b/libtui/widget/widget.ha
@@ -13,6 +13,8 @@ export type print = fn(w: *widget) (void | error);
 // A function that frees the resources associated to the widget.
 export type finish = fn(w: *widget) void;
 
+export type setsize = fn(w: *widget, sz: tty::ttysize) void;
+
 // An input listener on a widget. The returning value is intended to be used as
 // a signal that will be returned by [[notify]] in order to trigger certain more
 // global ui events (terminate the program, change widget focus, etc.). To
@@ -53,6 +55,7 @@ export type listener = *fn(w: *widget, r: libtui::key) bool;
 export type widget = struct {
 	print: nullable *print,
 	finish: nullable *finish,
+	setsize: nullable *setsize,
 	listeners: []listener,
 	ui: libtui::ttyui,
 };