Incorrect Escape Sequences in Lens Terminal on Windows Server 2022 with win32-input-mode

[unxed]

When running Far2l within the built-in terminal of Lens (a Kubernetes IDE) on Windows Server 2022, the win32-input-mode becomes active (TTY|w is seen), but the escape sequences generated for some keys are incorrect. For example:

• Enter: \x1b[0;0;13;1;0;1_\x1b[13;28;13;0;0;1_
• Ctrl-C: \x1b[17;29;0;1;8;1_\x1b[0;0;3;1;0;1_\x1b[67;46;3;0;8;1_\x1b[17;29;0;0;0;1_
• Esc: \x1b[0;0;27;1;0;1_\x1b[27;1;27;0;0;1_

This can be worked around by setting Virtual Key Code automatically based on Unicode key value, like this:

	// Workarounds for some weird win32-input-mode setups
	// Todo: add scan codes
	// Ctrl+letters
	if (
		(!args[0] && args[2] >= 1 && args[2] <= 26 && !(args[4] & LEFT_CTRL_PRESSED)) ||
		( args[0] && args[2] >= 1 && args[2] <= 26 &&  (args[4] & LEFT_CTRL_PRESSED))
	) {
		args[0] = args[2] + 64;
		args[2] = (args[4] & SHIFT_PRESSED) ? args[0] : tolower(args[0]);
		args[4] |= LEFT_CTRL_PRESSED;
		fprintf(stderr, "W32I: Ctrl+letter hack\n");
	}
	// Ctrl+BS
	if (args[0] == 0 && args[2] == 0x7F && args[3]) {
		args[0] = VK_BACK;
		args[2] = args[0];
		args[4] |= LEFT_CTRL_PRESSED;
		fprintf(stderr, "W32I: Ctrl+BS hack\n");
	}
	// Esc
	if (args[0] == 0 && args[2] == 0x1B && args[3]) {
		args[0] = VK_ESCAPE;
		fprintf(stderr, "W32I: Esc hack\n");
	}
	// Enter
	if (args[0] == 0 && args[2] == 0x0D && args[3]) {
		args[0] = VK_RETURN;
		fprintf(stderr, "W32I: Enter hack\n");
	}
	// Enter#2: Ctrl+M encoded as win32-input-mode seq, 77 0 109 1 8 1
	if (args[0] == 'M' && !args[1] && args[2] == 'm' && args[3] && (args[4] & LEFT_CTRL_PRESSED)) {
		args[0] = VK_RETURN;
		args[2] = 0x0D;
		args[4] = 0;
		fprintf(stderr, "W32I: Enter hack #2\n");
	}

Code from here: unxed@3ecf059

Another possible solution is key tracking (received keyup without corresponding keydown? generate keydown also) like it is done in pitty4far2l:

	if (args[3] && args[0]) { // keydown
		vkc_prev = args[0];
	} else if (args[0] && vkc_prev && (vkc_prev != (DWORD)args[0])) {
		args[3] = 1;
		vkc_prev = 0;
	}

Implemented here: unxed@203582d

But there is still a problem: our "win32-input-mode double encoding hack" prevents workarounds above from working with ESC key presses.

See also:
https://t.me/far2l_ru/36896

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Lens is using xterm.js for terminal implementation. xterm.js team is discussing win32-input-mode support, but it is not ready yet AFAIK:
xtermjs/xterm.js#2357

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@Dazzar56 you said you can look into this then you have a bit of free time, ?