Files
kte/ImGuiInputHandler.cc
T
Claude 2da35f57d1 ImGui: a suppressed text event no longer eats the next character (B8)
Ctrl+V, the zoom chords and new-window set a one-shot flag to drop the
text event their key press would produce, but SDL sends none for Ctrl
chords, so the flag dropped the next character typed instead (typing
"xyz" after Ctrl+V gave "yz", reproduced under Xvfb). The flag now
applies only until the next key press. C-k and Meta suffixes are still
suppressed (checked: C-k s saves without inserting "s"; M-f moves
without inserting "f").

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015rcVQiiWyTzoNrsvLSaAfB
2026-09-24 12:19:59 -07:00

652 lines
20 KiB
C++

#include <cstdio>
#include <algorithm>
#include <ncurses.h>
#include <SDL.h>
#include <imgui.h>
#include "ImGuiInputHandler.h"
#include "KKeymap.h"
#include "Editor.h"
#include "PasteSplit.h"
// Verbose k-prefix suffix logging for debugging macOS/SDL key translation
// issues. Default to off; enable by defining IMGUI_IH_DEBUG=1 at compile
// time. Mirrors QtInputHandler.cc's QT_IH_DEBUG gate.
#ifndef IMGUI_IH_DEBUG
#define IMGUI_IH_DEBUG 0
#endif
#if IMGUI_IH_DEBUG
#define IH_LOGF(...) do { std::fprintf(stderr, __VA_ARGS__); std::fflush(stderr); } while (0)
#else
#define IH_LOGF(...) ((void) 0)
#endif
static bool
map_key(const SDL_Keycode key,
const SDL_Keymod mod,
bool &k_prefix,
bool &esc_meta,
bool &k_ctrl_pending,
Editor *ed,
MappedInput &out,
bool &suppress_textinput_once)
{
// Ctrl handling
const bool is_ctrl = (mod & KMOD_CTRL) != 0;
const bool is_alt = (mod & (KMOD_ALT | KMOD_LALT | KMOD_RALT)) != 0;
// If previous key was ESC, interpret this as Meta via ESC keymap.
// Prefer KEYDOWN when we can derive a printable ASCII; otherwise defer to TEXTINPUT.
if (esc_meta) {
int ascii_key = 0;
if (key == SDLK_BACKSPACE) {
// ESC BACKSPACE: map to DeleteWordPrev using ncurses KEY_BACKSPACE constant
ascii_key = KEY_BACKSPACE;
} else if (key >= SDLK_a && key <= SDLK_z) {
ascii_key = static_cast<int>('a' + (key - SDLK_a));
} else if (key == SDLK_COMMA) {
ascii_key = '<';
} else if (key == SDLK_PERIOD) {
ascii_key = '>';
} else if (key == SDLK_LESS) {
ascii_key = '<';
} else if (key == SDLK_GREATER) {
ascii_key = '>';
}
if (ascii_key != 0) {
esc_meta = false; // consume if we can decide on KEYDOWN
ascii_key = KLowerAscii(ascii_key);
CommandId id;
if (KLookupEscCommand(ascii_key, id)) {
out = {true, id, "", 0};
return true;
}
// Known printable but unmapped ESC sequence: report invalid
out = {true, CommandId::UnknownEscCommand, "", 0};
return true;
}
// No usable ASCII from KEYDOWN → keep esc_meta set and let TEXTINPUT handle it
out.hasCommand = false;
return true;
}
// Movement and basic keys
// These keys exit k-prefix mode if active (user pressed C-k then a special key).
switch (key) {
case SDLK_LEFT:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::MoveLeft, "", 0};
return true;
case SDLK_RIGHT:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::MoveRight, "", 0};
return true;
case SDLK_UP:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::MoveUp, "", 0};
return true;
case SDLK_DOWN:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::MoveDown, "", 0};
return true;
case SDLK_HOME:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::MoveHome, "", 0};
return true;
case SDLK_END:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::MoveEnd, "", 0};
return true;
case SDLK_PAGEUP:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::PageUp, "", 0};
return true;
case SDLK_PAGEDOWN:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::PageDown, "", 0};
return true;
case SDLK_DELETE:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::DeleteChar, "", 0};
return true;
case SDLK_BACKSPACE:
k_prefix = false;
k_ctrl_pending = false;
out = {true, CommandId::Backspace, "", 0};
return true;
case SDLK_TAB:
// Insert a literal tab character when not interpreting a k-prefix suffix.
// If k-prefix is active, let the k-prefix handler below consume the key
// (so Tab doesn't leave k-prefix stuck).
if (!k_prefix) {
out = {true, CommandId::InsertText, std::string("\t"), 0};
return true;
}
break; // fall through so k-prefix handler can process
case SDLK_RETURN:
case SDLK_KP_ENTER:
k_prefix = false;
k_ctrl_pending = false;
if (mod & KMOD_SHIFT) {
out = {true, CommandId::SmartNewline, "", 0};
} else {
out = {true, CommandId::Newline, "", 0};
}
return true;
case SDLK_ESCAPE:
k_prefix = false;
k_ctrl_pending = false;
esc_meta = true; // next key will be treated as Meta
out.hasCommand = false; // no immediate command for bare ESC in GUI
return true;
default:
break;
}
// If we are in k-prefix, interpret the very next key via the C-k keymap immediately.
if (k_prefix) {
esc_meta = false;
// Normalize to ASCII; preserve case for letters using Shift
int ascii_key = 0;
if (key >= SDLK_a && key <= SDLK_z) {
ascii_key = static_cast<int>('a' + (key - SDLK_a));
if (mod & KMOD_SHIFT)
ascii_key = ascii_key - 'a' + 'A';
} else if (key == SDLK_COMMA) {
ascii_key = '<';
} else if (key == SDLK_PERIOD) {
ascii_key = '>';
} else if (key == SDLK_LESS) {
ascii_key = '<';
} else if (key == SDLK_GREATER) {
ascii_key = '>';
} else if (key >= SDLK_SPACE && key <= SDLK_z) {
ascii_key = static_cast<int>(key);
}
bool ctrl2 = (mod & KMOD_CTRL) != 0;
// If user typed a literal 'C' (uppercase) or '^' as a control qualifier, keep k-prefix active
// Do NOT treat lowercase 'c' as a qualifier; 'c' is a valid k-command (BufferClose).
if (ascii_key == 'C' || ascii_key == '^') {
k_ctrl_pending = true;
// Keep waiting for the next suffix; show status and suppress ensuing TEXTINPUT
if (ed)
ed->SetStatus("C-k C _");
suppress_textinput_once = true;
out.hasCommand = false;
return true;
}
// Otherwise, consume the k-prefix now for the actual suffix
k_prefix = false;
if (ascii_key != 0) {
int lower = KLowerAscii(ascii_key);
bool ctrl_suffix_supported = (lower == 'd' || lower == 'x' || lower == 'q');
bool pass_ctrl = (ctrl2 || k_ctrl_pending) && ctrl_suffix_supported;
k_ctrl_pending = false;
CommandId id;
bool mapped = KLookupKCommand(ascii_key, pass_ctrl, id);
#if IMGUI_IH_DEBUG
// Diagnostics for u/U
if (lower == 'u') {
char disp = (ascii_key >= 0x20 && ascii_key <= 0x7e)
? static_cast<char>(ascii_key)
: '?';
IH_LOGF(
"[kge] k-prefix suffix: sym=%d mods=0x%x ascii=%d '%c' ctrl2=%d pass_ctrl=%d mapped=%d id=%d\n",
static_cast<int>(key), static_cast<unsigned int>(mod), ascii_key, disp,
ctrl2 ? 1 : 0, pass_ctrl ? 1 : 0, mapped ? 1 : 0,
mapped ? static_cast<int>(id) : -1);
}
#endif
if (mapped) {
out = {true, id, "", 0};
if (ed)
ed->SetStatus(""); // clear "C-k _" hint after suffix
return true;
}
int shown = KLowerAscii(ascii_key);
char c = (shown >= 0x20 && shown <= 0x7e) ? static_cast<char>(shown) : '?';
std::string arg(1, c);
out = {true, CommandId::UnknownKCommand, arg, 0};
if (ed)
ed->SetStatus(""); // clear hint; handler will set unknown status
return true;
}
// Non-printable/unmappable key as k-suffix (e.g., F-keys): report unknown and exit k-mode
out = {true, CommandId::UnknownKCommand, std::string("?"), 0};
if (ed)
ed->SetStatus("");
return true;
}
if (is_ctrl) {
// Universal argument: C-u
if (key == SDLK_u) {
if (ed)
ed->UArgStart();
out.hasCommand = false;
return true;
}
// Cancel universal arg on C-g as well (it maps to Refresh via ctrl map)
if (key == SDLK_g) {
if (ed)
ed->UArgClear();
// Also cancel any pending k-prefix qualifier
k_ctrl_pending = false;
k_prefix = false; // treat as cancel of prefix
}
if (key == SDLK_k || key == SDLK_KP_EQUALS) {
k_prefix = true;
out = {true, CommandId::KPrefix, "", 0};
return true;
}
// Map other control chords via shared keymap
if (key >= SDLK_a && key <= SDLK_z) {
int ascii_key = static_cast<int>('a' + (key - SDLK_a));
CommandId id;
if (KLookupCtrlCommand(ascii_key, id)) {
out = {true, id, "", 0};
return true;
}
}
}
// Alt/Meta bindings (ESC f/b equivalent)
if (is_alt) {
int ascii_key = 0;
if (key == SDLK_BACKSPACE) {
// Alt BACKSPACE: map to DeleteWordPrev using ncurses KEY_BACKSPACE constant
ascii_key = KEY_BACKSPACE;
} else if (key >= SDLK_a && key <= SDLK_z) {
ascii_key = static_cast<int>('a' + (key - SDLK_a));
} else if (key == SDLK_COMMA) {
ascii_key = '<';
} else if (key == SDLK_PERIOD) {
ascii_key = '>';
} else if (key == SDLK_LESS) {
ascii_key = '<';
} else if (key == SDLK_GREATER) {
ascii_key = '>';
}
if (ascii_key != 0) {
CommandId id;
if (KLookupEscCommand(ascii_key, id)) {
out = {true, id, "", 0};
return true;
}
}
}
// If collecting universal argument, allow digits on KEYDOWN path too
if (ed && ed->UArg() != 0) {
if ((key >= SDLK_0 && key <= SDLK_9) && !(mod & KMOD_SHIFT)) {
int d = static_cast<int>(key - SDLK_0);
ed->UArgDigit(d);
out.hasCommand = false;
// We consumed a digit on KEYDOWN; SDL will often also emit TEXTINPUT for it.
// Request suppression of the very next TEXTINPUT to avoid double-counting.
suppress_textinput_once = true;
return true;
}
}
// k_prefix handled earlier
return false;
}
bool
ImGuiInputHandler::ProcessSDLEvent(const SDL_Event &e)
{
MappedInput mi;
bool produced = false;
switch (e.type) {
case SDL_MOUSEWHEEL: {
// High-resolution trackpads can deliver fractional wheel deltas. Accumulate
// precise values and emit one scroll step per whole unit.
float dy = 0.0f;
#if SDL_VERSION_ATLEAST(2, 0, 18)
dy = e.wheel.preciseY;
#else
dy = static_cast<float>(e.wheel.y);
#endif
#ifdef SDL_MOUSEWHEEL_FLIPPED
if (e.wheel.direction == SDL_MOUSEWHEEL_FLIPPED)
dy = -dy;
#endif
if (dy != 0.0f) {
wheel_accum_y_ += dy;
float abs_accum = wheel_accum_y_ >= 0.0f ? wheel_accum_y_ : -wheel_accum_y_;
int steps = static_cast<int>(abs_accum);
if (steps > 0) {
CommandId id = (wheel_accum_y_ > 0.0f) ? CommandId::ScrollUp : CommandId::ScrollDown;
std::lock_guard<std::mutex> lk(mu_);
for (int i = 0; i < steps; ++i) {
q_.push(MappedInput{true, id, std::string(), 0});
}
// remove the whole steps, keep fractional remainder
wheel_accum_y_ += (wheel_accum_y_ > 0.0f)
? -static_cast<float>(steps)
: static_cast<float>(steps);
return true; // consumed
}
}
return false;
}
case SDL_KEYDOWN: {
// A suppression request covers only the text event of the key that
// made it, which arrives before the next key press. Chords such as
// Ctrl+V produce no text event at all, and a leftover request ate
// the next character typed (B8).
suppress_text_input_once_ = false;
// Remember state before mapping; used for TEXTINPUT suppression heuristics
const bool was_k_prefix = k_prefix_;
const bool was_esc_meta = esc_meta_;
SDL_Keymod mods = SDL_Keymod(e.key.keysym.mod);
const SDL_Keycode key = e.key.keysym.sym;
// New window: Cmd+N (macOS) or Ctrl+Shift+N (Linux/Windows)
{
const bool gui_n = (mods & KMOD_GUI) && !(mods & KMOD_CTRL) && (key == SDLK_n);
const bool ctrl_sn = (mods & KMOD_CTRL) && (mods & KMOD_SHIFT) && (key == SDLK_n);
if (gui_n || ctrl_sn) {
std::lock_guard<std::mutex> lk(mu_);
q_.push(MappedInput{true, CommandId::NewWindow, std::string(), 0});
suppress_text_input_once_ = true;
return true;
}
}
// Font zoom: Cmd+=/Cmd+-/Cmd+0 (macOS) or Ctrl+=/Ctrl+-/Ctrl+0
if ((mods & (KMOD_CTRL | KMOD_GUI)) && !(mods & KMOD_SHIFT)) {
bool is_zoom = true;
CommandId zoom_cmd = CommandId::FontZoomIn;
if (key == SDLK_EQUALS || key == SDLK_PLUS)
zoom_cmd = CommandId::FontZoomIn;
else if (key == SDLK_MINUS)
zoom_cmd = CommandId::FontZoomOut;
else if (key == SDLK_0)
zoom_cmd = CommandId::FontZoomReset;
else
is_zoom = false;
if (is_zoom) {
std::lock_guard<std::mutex> lk(mu_);
q_.push(MappedInput{true, zoom_cmd, std::string(), 0});
suppress_text_input_once_ = true;
return true;
}
}
// Handle Paste: Ctrl+V (Windows/Linux) or Cmd+V (macOS)
// Note: SDL defines letter keycodes in lowercase only (e.g., SDLK_v). Shift does not change keycode.
if ((mods & (KMOD_CTRL | KMOD_GUI)) && (key == SDLK_v)) {
char *clip = SDL_GetClipboardText();
if (clip) {
std::string text(clip);
SDL_free(clip);
// Turn line breaks (\n, \r\n, or bare \r) into Newline
// commands and the rest into InsertText; InsertText itself
// rejects any embedded '\r'/'\n'.
// Into a prompt, line breaks must not become Newline: that
// would accept the prompt and send the rest to the buffer.
const bool to_prompt = ed_ && ed_->PromptActive();
std::lock_guard<std::mutex> lk(mu_);
for (const auto &cmd: to_prompt ? SplitPasteForPrompt(text) : SplitPasteIntoCommands(text))
q_.push(cmd);
// Suppress the corresponding TEXTINPUT that may follow
suppress_text_input_once_ = true;
return true; // consumed
}
}
{
bool suppress_req = false;
produced = map_key(key, mods,
k_prefix_, esc_meta_,
k_ctrl_pending_,
ed_,
mi,
suppress_req);
if (suppress_req) {
// Prevent the corresponding TEXTINPUT from delivering the same digit again
suppress_text_input_once_ = true;
}
}
// Note: Do NOT suppress SDL_TEXTINPUT after inserting a TAB. Most platforms
// do not emit TEXTINPUT for Tab, and suppressing here would incorrectly
// eat the next character typed if no TEXTINPUT follows the Tab press.
// If we just consumed a universal-argument digit or '-' on KEYDOWN and emitted UArgStatus,
// suppress the subsequent SDL_TEXTINPUT for this keystroke to avoid duplicating the digit in status.
// Additional suppression handled above when KEYDOWN consumed a uarg digit
// Suppress the immediate following SDL_TEXTINPUT when a printable KEYDOWN was used as a
// k-prefix suffix or Meta (Alt/ESC) chord, regardless of whether a command was produced.
const bool is_alt = (mods & (KMOD_ALT | KMOD_LALT | KMOD_RALT)) != 0;
const bool is_printable_letter = (key >= SDLK_SPACE && key <= SDLK_z);
const bool is_non_text_key =
key == SDLK_TAB || key == SDLK_RETURN || key == SDLK_KP_ENTER ||
key == SDLK_BACKSPACE || key == SDLK_DELETE || key == SDLK_ESCAPE ||
key == SDLK_LEFT || key == SDLK_RIGHT || key == SDLK_UP || key == SDLK_DOWN ||
key == SDLK_HOME || key == SDLK_END || key == SDLK_PAGEUP || key == SDLK_PAGEDOWN;
bool should_suppress = false;
if (!is_non_text_key) {
// Any k-prefix suffix that is printable should suppress TEXTINPUT, even if no
// command mapped (we report unknown via status instead of inserting text).
if (was_k_prefix && is_printable_letter) {
should_suppress = true;
}
// Alt/Meta + letter can also generate TEXTINPUT on some platforms
const bool is_meta_symbol = (
key == SDLK_COMMA || key == SDLK_PERIOD || key == SDLK_LESS || key ==
SDLK_GREATER);
if (is_alt && ((key >= SDLK_a && key <= SDLK_z) || is_meta_symbol)) {
should_suppress = true;
}
// ESC-as-meta followed by printable
if (was_esc_meta && (is_printable_letter || is_meta_symbol)) {
should_suppress = true;
}
}
if (should_suppress) {
suppress_text_input_once_ = true;
}
break;
}
case SDL_TEXTINPUT: {
// If the previous KEYDOWN requested suppression of this TEXTINPUT (e.g.,
// we already handled a uarg digit/minus or a k-prefix printable), do it
// immediately before any other handling to avoid duplicates.
if (suppress_text_input_once_) {
suppress_text_input_once_ = false; // consume suppression
produced = true; // consumed event
break;
}
// If editor universal argument is active, consume digit TEXTINPUT
if (ed_ &&ed_
->
UArg() != 0
)
{
const char *txt = e.text.text;
if (txt && *txt) {
unsigned char c0 = static_cast<unsigned char>(txt[0]);
if (c0 >= '0' && c0 <= '9') {
int d = c0 - '0';
ed_->UArgDigit(d);
produced = true; // consumed to update status
break;
}
}
// Non-digit ends collection; allow processing normally below
}
// If we are still in k-prefix and KEYDOWN path didn't handle the suffix,
// use TEXTINPUT's actual character (handles Shifted letters on macOS) to map the k-command.
if (k_prefix_) {
k_prefix_ = false;
esc_meta_ = false;
const char *txt = e.text.text;
if (txt && *txt) {
unsigned char c0 = static_cast<unsigned char>(txt[0]);
int ascii_key = 0;
if (c0 < 0x80) {
ascii_key = static_cast<int>(c0);
}
if (ascii_key != 0) {
// Qualifier via TEXTINPUT: uppercase 'C' or '^' only
if (ascii_key == 'C' || ascii_key == '^') {
k_ctrl_pending_ = true;
if (ed_)
ed_->SetStatus("C-k C _");
// Keep k-prefix active; do not emit a command
k_prefix_ = true;
produced = true;
break;
}
// Map via k-prefix table; do not pass Ctrl for TEXTINPUT case
CommandId id;
bool pass_ctrl = k_ctrl_pending_;
k_ctrl_pending_ = false;
bool mapped = KLookupKCommand(ascii_key, pass_ctrl, id);
#if IMGUI_IH_DEBUG
// Diagnostics: log any k-prefix TEXTINPUT suffix mapping
{
char disp = (ascii_key >= 0x20 && ascii_key <= 0x7e)
? static_cast<char>(ascii_key)
: '?';
IH_LOGF("[kge] k-prefix TEXTINPUT suffix: ascii=%d '%c' mapped=%d id=%d\n",
ascii_key, disp, mapped ? 1 : 0,
mapped ? static_cast<int>(id) : -1);
}
#endif
if (mapped) {
mi = {true, id, "", 0};
if (ed_)
ed_->SetStatus(""); // clear "C-k _" hint after suffix
produced = true;
break; // handled; do not insert text
} else {
// Unknown k-command via TEXTINPUT path
int shown = KLowerAscii(ascii_key);
char c = (shown >= 0x20 && shown <= 0x7e)
? static_cast<char>(shown)
: '?';
std::string arg(1, c);
mi = {true, CommandId::UnknownKCommand, arg, 0};
if (ed_)
ed_->SetStatus("");
produced = true;
break;
}
}
}
// If no usable ASCII was found, still report an unknown k-command and exit k-mode
mi = {true, CommandId::UnknownKCommand, std::string("?"), 0};
if (ed_)
ed_->SetStatus("");
produced = true;
break;
}
// (suppression is handled at the top of this case)
// Handle ESC-as-meta fallback on TEXTINPUT: some platforms emit only TEXTINPUT
// for the printable part after ESC. If esc_meta_ is set, translate first char.
if (esc_meta_) {
esc_meta_ = false; // consume meta prefix
const char *txt = e.text.text;
if (txt && *txt) {
// Parse first UTF-8 codepoint (we care only about common ASCII cases)
unsigned char c0 = static_cast<unsigned char>(txt[0]);
// Map a few common symbols/letters used in our ESC map
int ascii_key = 0;
if (c0 < 0x80) {
// ASCII path
ascii_key = static_cast<int>(c0);
ascii_key = KLowerAscii(ascii_key);
} else {
// Basic handling for macOS Option combos that might produce ≤/≥
// Compare the UTF-8 prefix for these two symbols
std::string s(txt);
if (s.rfind("\xE2\x89\xA4", 0) == 0) {
// U+2264 '≤'
ascii_key = '<';
} else if (s.rfind("\xE2\x89\xA5", 0) == 0) {
// U+2265 '≥'
ascii_key = '>';
}
}
if (ascii_key != 0) {
CommandId id;
if (KLookupEscCommand(ascii_key, id)) {
mi = {true, id, "", 0};
produced = true;
break;
}
}
}
// If we get here, unmapped ESC sequence via TEXTINPUT: report invalid
mi = {true, CommandId::UnknownEscCommand, "", 0};
produced = true;
break;
}
if (!k_prefix_ && e.text.text[0] != '\0') {
// Ensure InsertText never carries a newline; those must originate from KEYDOWN
std::string text(e.text.text);
// Strip any CR/LF that might slip through from certain platforms/IME behaviors
text.erase(std::remove(text.begin(), text.end(), '\n'), text.end());
text.erase(std::remove(text.begin(), text.end(), '\r'), text.end());
if (!text.empty()) {
mi.hasCommand = true;
mi.id = CommandId::InsertText;
mi.arg = std::move(text);
mi.count = 0;
produced = true;
} else {
// Nothing to insert after filtering; consume the event
produced = true;
}
} else {
produced = true; // consumed while k-prefix is active
}
break;
}
default:
break;
}
if (produced && mi.hasCommand) {
std::lock_guard<std::mutex> lk(mu_);
q_.push(mi);
}
return produced;
}
bool
ImGuiInputHandler::Poll(MappedInput &out)
{
std::lock_guard<std::mutex> lk(mu_);
if (q_.empty())
return false;
out = q_.front();
q_.pop();
return true;
}