#pragma once

#include "core/types.h"

// Raw input events -- Linux's evdev interface.
//
// The console gives characters. That is the right thing for a shell and the
// wrong thing for everything else: a character stream has no key *releases*,
// no way to tell left shift from right, no notion of a key being held, and no
// mouse at all. A game holding W to walk forward, or a compositor deciding
// which window a click landed in, needs the events underneath the characters.
//
// The layout is Linux's, deliberately. It is what every program that reads input
// already speaks -- SDL, X, libinput, every game engine -- so a program that
// runs on Linux reads input here without a porting layer. It costs nothing to
// match: the struct is four fields.
//
// Nodes are /dev/input/event0 (keyboard) and /dev/input/event1 (mouse).

struct input_timeval {
  int64 tv_sec;
  int64 tv_usec;
};

struct input_event {
  struct input_timeval time;
  uint16 type;
  uint16 code;
  int32  value;
};

// Event types.
#define EV_SYN          0x00
#define EV_KEY          0x01
#define EV_REL          0x02
#define EV_ABS          0x03
#define EV_MSC          0x04

#define SYN_REPORT      0

// Relative axes.
// Absolute axes, for a pointing device that reports where it *is* rather than
// how far it moved -- a tablet, a touchscreen, or a VM's absolute pointer.
// Same numbering as Linux, because /dev/input/eventN claims to speak evdev.
#define ABS_X           0x00
#define ABS_Y           0x01

#define REL_X           0x00
#define REL_Y           0x01
#define REL_WHEEL       0x08

// Buttons live in the EV_KEY code space alongside keys, which is why the
// keyboard's codes stop well below 0x100.
#define BTN_LEFT        0x110
#define BTN_RIGHT       0x111
#define BTN_MIDDLE      0x112

// Key codes worth naming. The rest are the AT scancode-set-1 numbers, which
// Linux's keycodes were derived from and still match for everything below
// 0x54 -- that is not a coincidence and it is why the PS/2 path needs no
// translation table for unprefixed bytes.
#define KEY_RESERVED    0
#define KEY_ESC         1
#define KEY_ENTER       28
#define KEY_LEFTCTRL    29
#define KEY_LEFTSHIFT   42
#define KEY_RIGHTSHIFT  54
#define KEY_LEFTALT     56
#define KEY_SPACE       57
#define KEY_RIGHTCTRL   97
#define KEY_RIGHTALT    100
#define KEY_HOME        102
#define KEY_UP          103
#define KEY_PAGEUP      104
#define KEY_LEFT        105
#define KEY_RIGHT       106
#define KEY_END         107
#define KEY_DOWN        108
#define KEY_PAGEDOWN    109
#define KEY_INSERT      110
#define KEY_DELETE      111
#define KEY_LEFTMETA    125
#define KEY_RIGHTMETA   126

#define KEY_MAX         255

// EVIOCGRAB -- take/release exclusive access to a device.
//
// Linux's _IOW('E', 0x90, int). Spelled as the resulting constant rather than
// built from an _IOW macro because SchOS has no ioctl-encoding macros and
// inventing a set just for this would be a bigger change than the feature.
// A non-zero argument grabs, zero releases; the argument is passed by value.
#define EVIOCGRAB       0x40044590

// Which device an event came from. Both are minor numbers under the input
// major, and both are the index into the driver's array.
#define INPUT_KBD       0
#define INPUT_MOUSE     1
#define NINPUTDEV       2