add: .line core event for line contents in non *raw mode* instead of .key core events

The end of the `.line` event received contents is highlighted by a trailing newline
(which cannot occur before, as that triggers the line event itself).

Add signal handler for SIGCONT which forces a `.resize` event that should re-draw the
contents after continuing a suspended application (i.e. ctrl+z followed by `fg`).

examples/direct.zig

@@ -46,6 +46,7 @@ const Prompt = struct {
         };
     }
 
+    // NOTE size hint is not required as the `.size = .{ .dim = .{..} }` property is set accordingly which denotes the minimal size
     // fn minSize(ctx: *anyopaque, _: *const App.Model, _: zterm.Point) zterm.Point {
     //     const this: *@This() = @ptrCast(@alignCast(ctx));
     //     return .{ .x = this.len, .y = 1 };
@@ -140,9 +141,8 @@ pub fn main() !void {
             switch (event) {
                 // NOTE maybe I want to decouple the `key`s from the user input too? i.e. this only makes sense if the output is not echoed!
                 // otherwise just use gnu's `readline`?
-                .key => |key| {
-                    // if (key.eql(.{ .cp = 'q' })) app.quit();
-                    _ = key;
+                .line => |line| {
+                    log.debug("{s}", .{line});
                 },
                 // NOTE errors could be displayed in another container in case one was received, etc. to provide the user with feedback
                 .err => |err| log.err("Received {s} with message: {s}", .{ @errorName(err.err), err.msg }),

src/app.zig

@@ -30,7 +30,7 @@ pub fn App(comptime M: type, comptime E: type) type {
         thread: ?Thread = null,
         quit_event: Thread.ResetEvent,
         termios: ?posix.termios = null,
-        winch_registered: bool = false,
+        handler_registered: bool = false,
         config: TerminalConfiguration,
 
         pub const TerminalConfiguration = struct {
@@ -63,6 +63,13 @@ pub fn App(comptime M: type, comptime E: type) type {
             // -> the signal might not work correctly when hosting the application over ssh!
             this.postEvent(.resize);
         }
+        /// registered CONT handler to force a complete redraw
+        fn handleCont(_: i32) callconv(.c) void {
+            const this: *@This() = @ptrCast(@alignCast(handler_ctx));
+            // NOTE this does not have to be done if in-band resize events are supported
+            // -> the signal might not work correctly when hosting the application over ssh!
+            this.postEvent(.resize);
+        }
 
         pub fn init(io: std.Io, model: Model) @This() {
             return .{
@@ -81,15 +88,19 @@ pub fn App(comptime M: type, comptime E: type) type {
             // post init event (as the very first element to be in the queue - event loop)
             this.postEvent(.init);
 
-            if (!this.winch_registered) {
+            if (!this.handler_registered) {
                 handler_ctx = this;
-                var act = posix.Sigaction{
+                posix.sigaction(posix.SIG.WINCH, &.{
                     .handler = .{ .handler = handleWinch },
                     .mask = posix.sigemptyset(),
                     .flags = 0,
-                };
-                posix.sigaction(posix.SIG.WINCH, &act, null);
-                this.winch_registered = true;
+                }, null);
+                posix.sigaction(posix.SIG.CONT, &.{
+                    .handler = .{ .handler = handleCont },
+                    .mask = posix.sigemptyset(),
+                    .flags = 0,
+                }, null);
+                this.handler_registered = true;
             }
 
             this.quit_event.reset();
@@ -437,9 +448,14 @@ pub fn App(comptime M: type, comptime E: type) type {
                                 var len = read_bytes;
                                 while (!std.unicode.utf8ValidateSlice(buf[0..len])) len -= 1;
                                 remaining_bytes = read_bytes - len;
-                                var iter: std.unicode.Utf8Iterator = .{ .bytes = buf[0..len], .i = 0 };
-                                while (iter.nextCodepoint()) |cp| this.postEvent(.{ .key = .{ .cp = cp } });
-                                continue;
+                                if (this.config.rawMode) {
+                                    var iter: std.unicode.Utf8Iterator = .{ .bytes = buf[0..len], .i = 0 };
+                                    while (iter.nextCodepoint()) |cp| this.postEvent(.{ .key = .{ .cp = cp } });
+                                    continue;
+                                } else {
+                                    this.postEvent(.{ .line = buf[0..len] });
+                                    continue;
+                                }
                             },
                         };
                         this.postEvent(.{ .key = key });

src/event.zig

@@ -23,6 +23,8 @@ pub const SystemEvent = union(enum) {
         /// associated error message
         msg: []const u8,
     },
+    /// Input line event received in non *raw mode* (instead of individual `key` events)
+    line: []const u8,
     /// Input key event received from the user
     key: Key,
     /// Mouse input event