From 9ad27924a62307c583625bf4994d317a4303363d Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Wed, 20 Sep 2023 14:33:55 -0700
Subject: [PATCH] input: correct xterm encoding for modified F1-F4

Fixes #499
---
 src/input/KeyEncoder.zig    | 46 +++++++++++++++++++++++++++++++++++++
 src/input/function_keys.zig |  8 +++----
 2 files changed, 50 insertions(+), 4 deletions(-)

diff --git a/src/input/KeyEncoder.zig b/src/input/KeyEncoder.zig
index 51b80197a..4be5adf31 100644
--- a/src/input/KeyEncoder.zig
+++ b/src/input/KeyEncoder.zig
@@ -1106,6 +1106,52 @@ test "legacy: keypad enter" {
     try testing.expectEqualStrings("\r", actual);
 }
 
+test "legacy: f1" {
+    var buf: [128]u8 = undefined;
+    var enc: KeyEncoder = .{
+        .event = .{
+            .key = .f1,
+            .mods = .{ .ctrl = true },
+            .consumed_mods = .{},
+        },
+    };
+
+    // F1
+    {
+        enc.event.key = .f1;
+        const actual = try enc.legacy(&buf);
+        try testing.expectEqualStrings("\x1b[1;5P", actual);
+    }
+
+    // F2
+    {
+        enc.event.key = .f2;
+        const actual = try enc.legacy(&buf);
+        try testing.expectEqualStrings("\x1b[1;5Q", actual);
+    }
+
+    // F3
+    {
+        enc.event.key = .f3;
+        const actual = try enc.legacy(&buf);
+        try testing.expectEqualStrings("\x1b[1;5R", actual);
+    }
+
+    // F4
+    {
+        enc.event.key = .f4;
+        const actual = try enc.legacy(&buf);
+        try testing.expectEqualStrings("\x1b[1;5S", actual);
+    }
+
+    // F5 uses new encoding
+    {
+        enc.event.key = .f5;
+        const actual = try enc.legacy(&buf);
+        try testing.expectEqualStrings("\x1b[15;5~", actual);
+    }
+}
+
 test "ctrlseq: normal ctrl c" {
     const seq = ctrlSeq(.c, .{ .ctrl = true });
     try testing.expectEqual(@as(u8, 0x03), seq.?);
diff --git a/src/input/function_keys.zig b/src/input/function_keys.zig
index 9c6c486d3..9721130d1 100644
--- a/src/input/function_keys.zig
+++ b/src/input/function_keys.zig
@@ -87,10 +87,10 @@ pub const keys = keys: {
     result.set(.page_down, pcStyle("\x1b[6;{}~") ++ .{.{ .sequence = "\x1B[6~" }});
 
     // Function Keys. todo: f13-f35 but we need to add to input.Key
-    result.set(.f1, pcStyle("\x1b[11;{}~") ++ .{.{ .sequence = "\x1BOP" }});
-    result.set(.f2, pcStyle("\x1b[12;{}~") ++ .{.{ .sequence = "\x1BOQ" }});
-    result.set(.f3, pcStyle("\x1b[13;{}~") ++ .{.{ .sequence = "\x1BOR" }});
-    result.set(.f4, pcStyle("\x1b[14;{}~") ++ .{.{ .sequence = "\x1BOS" }});
+    result.set(.f1, pcStyle("\x1b[1;{}P") ++ .{.{ .sequence = "\x1BOP" }});
+    result.set(.f2, pcStyle("\x1b[1;{}Q") ++ .{.{ .sequence = "\x1BOQ" }});
+    result.set(.f3, pcStyle("\x1b[1;{}R") ++ .{.{ .sequence = "\x1BOR" }});
+    result.set(.f4, pcStyle("\x1b[1;{}S") ++ .{.{ .sequence = "\x1BOS" }});
     result.set(.f5, pcStyle("\x1b[15;{}~") ++ .{.{ .sequence = "\x1B[15~" }});
     result.set(.f6, pcStyle("\x1b[17;{}~") ++ .{.{ .sequence = "\x1B[17~" }});
     result.set(.f7, pcStyle("\x1b[18;{}~") ++ .{.{ .sequence = "\x1B[18~" }});