Files
ghostty/src/terminal/ScreenSet.zig
Mitchell Hashimoto 3aff5f0aff ScreenSet
2025-11-14 15:08:10 -08:00

107 lines
2.9 KiB
Zig

/// A ScreenSet holds multiple terminal screens. This is initially created
/// to handle simple primary vs alternate screens, but could be extended
/// in the future to handle N screens.
///
/// One of the goals of this is to allow lazy initialization of screens
/// as needed. The primary screen is always initialized, but the alternate
/// screen may not be until first used.
const ScreenSet = @This();
const std = @import("std");
const assert = std.debug.assert;
const testing = std.testing;
const Allocator = std.mem.Allocator;
const Screen = @import("Screen.zig");
/// The possible keys for screens in the screen set.
pub const Key = enum(u1) {
primary,
alternate,
};
/// The key value of the currently active screen. Useful for simple
/// comparisons, e.g. "is this screen the primary screen".
active_key: Key,
/// The active screen pointer.
active: *Screen,
/// All screens that are initialized.
all: std.EnumMap(Key, *Screen),
pub fn init(
alloc: Allocator,
opts: Screen.Options,
) !ScreenSet {
// We need to initialize our initial primary screen
const screen = try alloc.create(Screen);
errdefer alloc.destroy(screen);
screen.* = try .init(alloc, opts);
return .{
.active_key = .primary,
.active = screen,
.all = .init(.{ .primary = screen }),
};
}
pub fn deinit(self: *ScreenSet, alloc: Allocator) void {
// Destroy all initialized screens
var it = self.all.iterator();
while (it.next()) |entry| {
entry.value.*.deinit();
alloc.destroy(entry.value.*);
}
}
/// Get the screen for the given key, if it is initialized.
pub fn get(self: *const ScreenSet, key: Key) ?*Screen {
return self.all.get(key);
}
/// Get the screen for the given key, initializing it if necessary.
pub fn getInit(
self: *ScreenSet,
alloc: Allocator,
key: Key,
opts: Screen.Options,
) !*Screen {
if (self.get(key)) |screen| return screen;
const screen = try alloc.create(Screen);
errdefer alloc.destroy(screen);
screen.* = try .init(alloc, opts);
self.all.put(key, screen);
return screen;
}
/// Remove a key from the set. The primary screen cannot be removed (asserted).
pub fn remove(
self: *ScreenSet,
alloc: Allocator,
key: Key,
) void {
assert(key != .primary);
if (self.all.fetchRemove(key)) |screen| {
screen.deinit();
alloc.destroy(screen);
}
}
/// Switch the active screen to the given key. Requires that the
/// screen is initialized.
pub fn switchTo(self: *ScreenSet, key: Key) void {
self.active_key = key;
self.active = self.all.get(key).?;
}
test ScreenSet {
const alloc = testing.allocator;
var set: ScreenSet = try .init(alloc, .default);
defer set.deinit(alloc);
try testing.expectEqual(.primary, set.active_key);
// Initialize a secondary screen
_ = try set.getInit(alloc, .alternate, .default);
set.switchTo(.alternate);
try testing.expectEqual(.alternate, set.active_key);
}