esc dispatch is handled in parser

src/terminal/Parser.zig

@@ -63,11 +63,19 @@ pub const Action = union(enum) {
     /// structure are only valid until the next call to "next".
     csi_dispatch: CSI,
 
+    /// Execute the ESC command.
+    esc_dispatch: ESC,
+
     pub const CSI = struct {
         intermediates: []u8,
         params: []u16,
         final: u8,
     };
+
+    pub const ESC = struct {
+        intermediates: []u8,
+        final: u8,
+    };
 };
 
 /// Maximum number of intermediate characters during parsing.
@@ -192,6 +200,12 @@ fn doAction(self: *Parser, action: TransitionAction, c: u8) ?Action {
                 },
             };
         },
+        .esc_dispatch => Action{
+            .esc_dispatch = .{
+                .intermediates = self.intermediates[0..self.intermediates_idx],
+                .final = c,
+            },
+        },
         else => {
             std.log.err("unimplemented action: {}", .{action});
             @panic("TODO");

src/terminal/Terminal.zig

@@ -129,6 +129,7 @@ pub fn appendChar(self: *Terminal, alloc: Allocator, c: u8) !void {
             .print => |p| try self.print(alloc, p),
             .execute => |code| try self.execute(alloc, code),
             .csi_dispatch => |csi| try self.csiDispatch(alloc, csi),
+            .esc_dispatch => |esc| log.warn("unhandled esc: {}", .{esc}),
         }
     }
 }
@@ -289,7 +290,13 @@ pub fn eraseLine(
 ) !void {
     switch (mode) {
         .right => {
+            // If our cursor is outside our screen, we can't erase anything.
+            if (self.cursor.y >= self.screen.items.len) return;
             var line = &self.screen.items[self.cursor.y];
+
+            // If our cursor is outside our screen, we can't erase anything.
+            if (self.cursor.x >= line.items.len) return;
+
             for (line.items[self.cursor.x..line.items.len]) |*cell|
                 cell.char = 0;
         },