Files
kte/TerminalInputHandler.cpp
2025-11-29 17:54:55 -08:00

94 lines
3.1 KiB
C++

#include "TerminalInputHandler.h"
#include <ncurses.h>
namespace {
constexpr int CTRL(char c) { return c & 0x1F; }
}
TerminalInputHandler::TerminalInputHandler() = default;
TerminalInputHandler::~TerminalInputHandler() = default;
static bool map_key_to_command(int ch, bool &k_prefix, MappedInput &out)
{
// Handle special keys from ncurses
switch (ch) {
case KEY_LEFT: out = {true, CommandId::MoveLeft, "", 0}; return true;
case KEY_RIGHT: out = {true, CommandId::MoveRight, "", 0}; return true;
case KEY_UP: out = {true, CommandId::MoveUp, "", 0}; return true;
case KEY_DOWN: out = {true, CommandId::MoveDown, "", 0}; return true;
case KEY_HOME: out = {true, CommandId::MoveHome, "", 0}; return true;
case KEY_END: out = {true, CommandId::MoveEnd, "", 0}; return true;
case KEY_DC: out = {true, CommandId::DeleteChar,"", 0}; return true;
case KEY_RESIZE: out = {true, CommandId::Refresh, "", 0}; return true;
default: break;
}
// ESC as cancel of prefix; many terminals send meta sequences as ESC+...
if (ch == 27) { // ESC
k_prefix = false;
out = {true, CommandId::Refresh, "", 0};
return true;
}
// Control keys
if (ch == CTRL('K')) { // C-k prefix
k_prefix = true;
out = {true, CommandId::Refresh, "", 0};
return true;
}
if (ch == CTRL('G')) { // cancel
k_prefix = false;
out = {true, CommandId::Refresh, "", 0};
return true;
}
if (ch == CTRL('L')) { out = {true, CommandId::Refresh, "", 0}; return true; }
if (ch == CTRL('S')) { out = {true, CommandId::FindStart, "", 0}; return true; }
// Enter
if (ch == '\n' || ch == '\r') { k_prefix = false; out = {true, CommandId::Newline, "", 0}; return true; }
// Backspace in ncurses can be KEY_BACKSPACE or 127
if (ch == KEY_BACKSPACE || ch == 127 || ch == CTRL('H')) { k_prefix = false; out = {true, CommandId::Backspace, "", 0}; return true; }
if (k_prefix) {
k_prefix = false; // single next key only
switch (ch) {
case 's': case 'S': out = {true, CommandId::Save, "", 0}; return true;
case 'x': case 'X': out = {true, CommandId::SaveAndQuit, "", 0}; return true;
case 'q': case 'Q': out = {true, CommandId::Quit, "", 0}; return true;
default: break;
}
if (ch == CTRL('Q')) { out = {true, CommandId::Quit, "", 0}; return true; }
out.hasCommand = false; // unknown chord
return true;
}
// Printable ASCII
if (ch >= 0x20 && ch <= 0x7E) {
out.hasCommand = true;
out.id = CommandId::InsertText;
out.arg.assign(1, static_cast<char>(ch));
out.count = 0;
return true;
}
out.hasCommand = false;
return true; // consumed a key
}
bool TerminalInputHandler::decode_(MappedInput &out)
{
int ch = getch();
if (ch == ERR) {
return false; // no input
}
return map_key_to_command(ch, k_prefix_, out);
}
bool TerminalInputHandler::Poll(MappedInput &out)
{
out = {};
return decode_(out) && out.hasCommand;
}