#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>
#include <systemd/sd-bus.h>
#include <errno.h>
#include <linux/input.h>

#include "utils.h"
#include "shared.h"
#include "rcm-server-main.h"
#include "rcm-server-evdev.h"
#include "rcm-server-keymap.h"

struct rc_scancode {
	__u16 protocol;
	__u16 reserved[3];
	__u64 scancode;
};

#define INPUT_KEYMAP_BY_INDEX   (1 << 0)
struct rc_keymap_entry {
	__u8  flags;
	__u8  len;
	__u16 index;
	__u32 keycode;
	union {
		struct rc_scancode rc;
		__u8 scancode[32];
	} u;
	char end[];
};
#define RKE_SIZE (sizeof(struct rc_scancode))

const char *
evdev_guess_protocol(struct device *device, uint64_t scancode, uint32_t keycode)
{
	struct rc_keymap_entry rke;
	unsigned i;

	if (!device || device->evdev_fd < 0)
		return NULL;

	for (i = 0; ; i++) {
		memset(&rke, 0, sizeof(rke));
		rke.len = RKE_SIZE;
		rke.index = i;
		rke.flags = INPUT_KEYMAP_BY_INDEX;
		if (ioctl(device->evdev_fd, EVIOCGKEYCODE_V2, &rke))
			break;

		if (rke.u.rc.scancode != scancode)
			continue;

		if (rke.keycode != keycode)
			continue;

		if (rke.u.rc.protocol > ARRAY_SIZE(rc_protocols))
			return NULL;

		return rc_protocols[rke.u.rc.protocol];
	}

	return NULL;
}

static int
evdev_clear_keymap(struct device *device)
{
	struct rc_keymap_entry rke;
	unsigned count = 0;
	int r = 0;

	printf("Clearing keymap...");
	while (true) {
		memset(&rke, 0, sizeof(rke));
		rke.len = RKE_SIZE;
		rke.index = 0;
		rke.flags = INPUT_KEYMAP_BY_INDEX;
		if (ioctl(device->evdev_fd, EVIOCGKEYCODE_V2, &rke)) {
			printf("done (%u entries removed)\n", count);
			break;
		}

		/*
		printf("  Clearing 0x%08llX (0x%02X) to 0x%02X\n",
		       rke.u.rc.scancode, rke.u.rc.protocol, rke.keycode);
		       */

		rke.keycode = KEY_RESERVED;
		if (ioctl(device->evdev_fd, EVIOCSKEYCODE_V2, &rke)) {
			r = -errno;
			printf("failed (%s)\n", strerror(errno));
			break;
		}
		count++;
	}

	return r;
}

static void
set_keycode_new(struct device *device, __u16 protocol, __u64 scancode, __u32 keycode)
{
	struct rc_keymap_entry rke;

	memset(&rke, 0, sizeof(rke));
	rke.len = RKE_SIZE;
	rke.u.rc.protocol = protocol;
	rke.u.rc.scancode = scancode;
	rke.keycode = keycode;

	printf("Setting keycode (new ioctl) 0x%08llX (0x%02X) to 0x%02X\n",
	       rke.u.rc.scancode, rke.u.rc.protocol, rke.keycode);

	if (ioctl(device->evdev_fd, EVIOCSKEYCODE_V2, &rke)) {
		printf("Unable to call SETKEYCODE2 ioctl\n");
		exit(EXIT_FAILURE);
	}
}

static int
evdev_set_keymap(struct device *device, struct keymap *keymap)
{
	unsigned i;

	printf("\tSetting up keymap: %s\n", keymap->name);

	for (i = 0; i < keymap->keycode_count; i++)
		set_keycode_new(device,
				keymap->keycodes[i].protocol,
				keymap->keycodes[i].scancode,
				keymap->keycodes[i].lik->value);

	printf("\tDone: %u entries added\n", i);
	return 0;
}

int
evdev_setup(struct device *device)
{
	int r;
	struct keymap *keymap;

	if (!device || device->evdev_fd < 0)
		return -EINVAL;

	printf("Performing evdev setup for device %s\n", device->path);
	r = evdev_clear_keymap(device);
	if (r < 0)
		return r;

	list_for_each_entry(keymap, &device->keymaps, list)
		r = evdev_set_keymap(device, keymap);

	return r;
}