vibes acme-like text editing?

1 files changed, 27 insertions, 0 deletions

diff --git a/term.zig b/term.zig
index a07469e7..d5030e5b 100644
--- a/term.zig
+++ b/term.zig
@@ -11,6 +11,19 @@ pub const Sel = struct {
     r1: i32 = 0,
 };
 
+pub const EDIT_CAP = 128; // max chars in one insertion run
+pub const MAX_EDITS = 16; // max concurrent insertion runs per window
+
+/// A run of inserted ("char mode") text. `col` is the ORIGINAL tty column it is
+/// spliced in *before* — the run shifts the underlying row right, it doesn't
+/// overwrite. `row`/`col` are pane-local (row carries the BOX_H tag offset).
+pub const Edit = struct {
+    row: i32 = 0,
+    col: i32 = 0,
+    len: u16 = 0,
+    text: [EDIT_CAP]u8 = undefined,
+};
+
 /// Persistent per-terminal state: the pty handle, the ghostty emulator and its
 /// (stateful) VT parser, the background reader task, plus its layout weight and
 /// text selection.
@@ -36,6 +49,20 @@ vweight: f32 = 1,
 /// One independent selection per mouse button: 0=left, 1=middle, 2=right.
 sel: [3]Sel = .{ .{}, .{}, .{} },
 
+/// modal input. false = "sym" mode (keys -> pty as terminal sequences),
+/// true = "char" mode (keys insert text at the cursor). a left-click enters
+/// char mode and anchors the cursor; Esc leaves it.
+///
+/// The cursor and edits are anchored at ABSOLUTE body rows (visual row + scroll
+/// offset) so they ride the scrollback, not the screen. `cur_off` is the offset
+/// into the run sitting at (cur_row, cur_col).
+editing: bool = false,
+cur_row: i32 = 0,
+cur_col: i32 = 0,
+cur_off: u16 = 0,
+nedits: usize = 0,
+edits: [MAX_EDITS]Edit = @splat(.{}),
+
 pub fn deinit(self: *Term, io: std.Io, gpa: std.mem.Allocator) void {
     _ = self.reader.cancel(io) catch {};
     self.stream.deinit();