/*
 * (c) 2011 Siegen, Germany by Nils Faerber
 *
 * license LGPL
 */
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <termios.h>

#include "metawatch_protocol.h"
#include "crc16ccitt.h"


#define MW_FRAME_DELAY		0x00

void dump_frame(unsigned char *frame, int len)
{
	int i;

	for (i=0; i<len; i++)
		fprintf(stderr, "0x%02x ", frame[i]);
	fprintf(stderr, "\n");
}


int mw_send_frame(int mw_fd, unsigned char msg_type, unsigned char options, unsigned char *data, unsigned char len)
{
	unsigned short crc;
	unsigned char frame[64];
	int tlen = len + 6; /* payload + 6 bytes frameing */
	int ret;

	memset(frame, 0, 64);
	frame[0] = MW_SOF;
	frame[1] = len + 6;
	frame[2] = msg_type;
	frame[3] = options;
	if (data != NULL && len > 0)
		memcpy(frame+4, data, len);

	crc = crc16ccitt(frame, len+4);
	*(unsigned short *)(frame+len+4) = crc;

	dump_frame(frame, tlen);

	while (((ret = write(mw_fd, frame, tlen)) >= 0) && (tlen > 0))
		tlen -= ret;

	if (MW_FRAME_DELAY)
		usleep(MW_FRAME_DELAY);

	if (tlen == 0 && ret >= 0)
		return 0;
	else
		return ret;
}

/*
 * host to watch commands
 */

void mw_set_rtc(int mw_fd, unsigned char clk1224, unsigned char date_fmt)
{
	time_t mtime;
	struct tm mtm;
	unsigned short year;
	unsigned char data[32];

	mtime = time(NULL);
	localtime_r(&mtime, &mtm);

	year = mtm.tm_year + 1900;  
	data[0] = (year & 0x0f00) >> 8;
	data[1] = (year & 0x00ff);
	data[2] = mtm.tm_mon + 1;
	data[3] = mtm.tm_mday;
	data[4] = mtm.tm_wday;
	data[5] = mtm.tm_hour;
	data[6] = mtm.tm_min;
	data[7] = mtm.tm_sec;
	data[8] = clk1224;
	data[9] = date_fmt;

	mw_send_frame(mw_fd, MW_SET_REAL_TIME_CLOCK, 0, data, 10);
}

void mw_set_vibrate_mode(int mw_fd, unsigned char enable, unsigned short on_time, unsigned short off_time, unsigned char cycles)
{
	unsigned char mdata[7];

	mdata[0] = enable;
	*(unsigned short *)(mdata+1) = on_time; /* miliseconds */
	*(unsigned short *)(mdata+3) = off_time; /* miliseconds */
	mdata[5] = cycles;
	mw_send_frame(mw_fd, MW_SET_VIBRATE_MODE, 0, mdata, 6);
}

void mw_configure_watch_mode(int mw_fd, unsigned char mode, unsigned char save, unsigned char timeout, unsigned char invert)
{
	unsigned char mdata[3];

	mdata[0] = timeout; /* seconds */
	mdata[1] = invert; /* 0=normal, 1=invert */
	mw_send_frame(mw_fd, MW_CONFIGURE_MODE, (mode & 0x0f) | ((save & 0x01) << 3), mdata, 2);
}

void mw_update_display(int mw_fd, unsigned char mode, unsigned char copy)
{
	mw_send_frame(mw_fd, MW_UPDATE_DISPLAY, (mode & 0x0f) | ((copy & 0x01) << 3), NULL, 0);
}

void mw_load_template(int mw_fd, unsigned char mode, unsigned char template_select)
{
	mw_send_frame(mw_fd, MW_LOAD_TEMPLATE, (mode & 0x0f), &template_select, 1);
}

/*
 * send line for screen-mode mode from *buffer to watch, starting at display row row_offset
 */
void mw_write_buffer(int mw_fd,
		unsigned char mode,
		unsigned char numlines,		/* number of lines, 0 or 1 */
		unsigned char row_offset,	/* start at row_offset in display, e.g. lower part in idle @31 */
		unsigned char *buffer, int buflen)
{
	unsigned char mdata[32];

	buflen = 12 * (buflen / 12);	/* crop to 12 bytes */
	if ((numlines == 0 && buflen < 12) || (numlines == 1 && buflen < 24)) {
		fprintf(stderr, "mw_write_buffer: bufferlen does not match number of lines\n");
		return;
	};
	memset(mdata, 0, 32);
	mdata[0] = row_offset;
	memcpy((mdata+1), buffer, 12);
	if (numlines == 1) {
		mdata[0] = row_offset+1;
		memcpy((mdata+13), (buffer+12), 12);
	};
	mw_send_frame(mw_fd, MW_WRITE_BUFFER, (mode & 0x0f) | (((numlines & 0x01)<< 3) & 0x10), mdata, numlines ? 13 : 26);
}


/* ------------------------------------------------------------------------ */


/*
 * watch responses, events or notifications
 */
void mw_get_real_time_clock_response(int mw_fd, unsigned char *rtcrsp, int len)
{
	struct tm mtm;
	unsigned short year;
	unsigned char clk1224, date_fmt;

	if (len != 10) {
		fprintf(stderr, "get real time clock response too short %d != 10\n", len);
		return;
	}

	year = *(unsigned short *)rtcrsp;
	mtm.tm_year = year - 1900;
	mtm.tm_mon = rtcrsp[2] - 1;
	mtm.tm_mday = rtcrsp[3];
	mtm.tm_wday = rtcrsp[4];
	mtm.tm_hour = rtcrsp[5];
	mtm.tm_min = rtcrsp[6];
	mtm.tm_sec = rtcrsp[7];
	clk1224 = rtcrsp[8];
	date_fmt = rtcrsp[9];

	fprintf(stderr, "watch RTC is %s, clock format is %s, date format is %s\n", asctime(&mtm), clk1224 ? "24h" : "AM/PM", date_fmt ? "DD/MM" : "MM/DD");
}

void mw_get_battery_voltage_response(int mw_fd, unsigned char *batrsp, int len)
{
	unsigned short voltage = *(unsigned short *)batrsp;
	unsigned char power_good = batrsp[2];
	unsigned char bat_charging = batrsp[3];

	fprintf(stderr, "battery is at %dV, %s and %s\n", voltage, power_good ? "power is good" : "power fault", bat_charging ? "charging" : "not charging");
}

/* ---------------------------------------------------------------------- */

int decode_frame(int mw_fd, unsigned char *buf, int len)
{
	unsigned short crc;
	unsigned char msglen;
	unsigned char msgtype;
	unsigned char msgopt;
	unsigned char *msgdata;

	/* check frame */
	crc = *(unsigned short *)(buf+len-2);
	if (crc != crc16ccitt(buf, len-2)) {
		fprintf(stderr, "decode frame CRC error\n");
		return 1;
	} else
		fprintf(stderr, "decode frame CRC OK\n");
	if (buf[0] != MW_SOF) {
		fprintf(stderr, "decode frame SOF not found\n");
		return 1;
	} else
	fprintf(stderr, "decode frame found SOF\n");

	msglen = buf[1];
	msgtype = buf[2];
	msgopt = buf[3];
	msgdata = (buf+4);

	switch (msgtype) {
		case MW_GET_REAL_TIME_CLOCK_RSP:
			mw_get_real_time_clock_response(mw_fd, msgdata, len-4-2);
			break;
		case MW_GET_INFORMATION_STRING_RSP:
			msgdata[len-4-2] = 0;
			fprintf(stderr, "Got info string '%s'\n", (msgdata+4));
			break;
		case MW_READ_BATTERY_VOLTAGE_RSP:
			mw_get_battery_voltage_response(mw_fd, msgdata, len-4-2);
			break;
		case MW_LOW_BATTERY_WARNING_MSG:
			fprintf(stderr, "Watch battery low, please connect charger\n");
			break;
		case MW_LOW_BATTERY_BT_OFF_MSG:
			fprintf(stderr, "Watch battery extremely low - radio will turn off\n");
			break;
		default:
			fprintf(stderr, "Unkown msgtype 0x%02x\n", msgtype);
			break;
	};

	return 0;
}


void process_cmd(char *cmdline, int clinep, int mw_fd)
{
	unsigned char mdata[32];

	fprintf(stderr, "command: '%s'\n", cmdline);

	if (strncmp(cmdline, "quit", 4) == 0) {
		close(mw_fd);
		exit(0);
	}

	if (strncmp(cmdline, "srtc", 4) == 0) {
		fprintf(stderr, "Setting RTC from system time...");
		mw_set_rtc(mw_fd, MW_RTC_CLOCK_24HR, MW_RTC_DATE_DDMM);
		fprintf(stderr, "OK\n");
	}
	if (strncmp(cmdline, "grtc", 4) == 0) {
		mw_send_frame(mw_fd, MW_GET_REAL_TIME_CLOCK, 0, NULL, 0);
	}
	if (strncmp(cmdline, "gistr", 5) == 0) {
		mdata[0] = 0;
		mw_send_frame(mw_fd, MW_GET_INFORMATION_STRING, 0, mdata, 1);
	}
	if (strncmp(cmdline, "gdtype", 6) == 0) {
		mw_send_frame(mw_fd, MW_GET_DEVICE_TYPE, 0, NULL, 0);
	}
	if (strncmp(cmdline, "rvbat", 5) == 0) {
		mw_send_frame(mw_fd, MW_READ_BATTERY_VOLTAGE_MSG, 0, NULL, 0);
	}
	if (strncmp(cmdline, "modecfg", 6) == 0) {
		mw_configure_watch_mode(mw_fd, MW_SCREEN_MODE_IDLE, 0, 4, 1);
		mw_update_display(mw_fd, MW_SCREEN_MODE_IDLE, 0);
	}
	if (strncmp(cmdline, "rbtcfg", 6) == 0) {
		mdata[0] = 0; /* idle screen */
		mdata[1] = 1; /* button index */
		mdata[2] = 2; /* button press type */
		mdata[3] = 3; /* callback message type */
		mdata[4] = 4; /* callback message option */
		mw_send_frame(mw_fd, MW_READ_BUTTON_CONFIG, 0, NULL, 0);
	}
	if (strncmp(cmdline, "svib", 4) == 0) {
		mw_set_vibrate_mode(mw_fd, 1, 300, 300, 5);
	}
}


int menu(int mw_fd)
{
	fd_set mfds;
	struct termios tconfd;
	char cmdline[128];
	unsigned char msg_buf[64];
	unsigned char clinep = 0;
	int rcvd;

	tcgetattr(0, &tconfd);
	cfmakeraw(&tconfd);
	tconfd.c_oflag |= ONLCR | OPOST;
	tconfd.c_lflag |= ISIG;
	tcsetattr(0, TCSANOW, &tconfd);

	FD_ZERO(&mfds);
	FD_SET(0, &mfds);
	FD_SET(mw_fd, &mfds);

	memset(cmdline, 0, 128);

	do {
		rcvd = 0;
		if (select(mw_fd+1, &mfds, NULL, NULL, NULL) > 0) {
			if (FD_ISSET(mw_fd, &mfds)) {
				rcvd = read(mw_fd, msg_buf, 64);
				fprintf(stderr, "read %d bytes:\n", rcvd);
				if (rcvd > 0) {
					dump_frame(msg_buf, rcvd);
					decode_frame(mw_fd, msg_buf, rcvd);
				}
			};
			if (FD_ISSET(0, &mfds)) {
				rcvd = read(0, (cmdline+clinep), 1);
				if (rcvd > 0) {
					if (cmdline[clinep] == '\r') {
						printf("\n");
						cmdline[clinep--] = '\0';
						process_cmd(cmdline, clinep, mw_fd);
						clinep = 0;
						memset(cmdline, 0, 128);
					} else {
						clinep++;
						if (clinep > 75)
							clinep = 75;
						printf("\r> %s", cmdline);
						fflush(stdout);
					}
				}
			};
		} else
			break;
		FD_ZERO(&mfds);
		FD_SET(0, &mfds);
		FD_SET(mw_fd, &mfds);
	} while (rcvd > 0);

	return 0;
}

int main(int argc, char **argv)
{
	int mw_fd;

	if (argc != 2) {
		fprintf(stderr, "Usage:\n\t%s <devicename>\n", argv[0]);
		return 1;
	};
  
	crc16ccitt_init();

	mw_fd = open(argv[1], O_RDWR);
	if (mw_fd < 0) {
		perror("open");
		return 1;
	};

	menu(mw_fd);

	fsync(mw_fd);

	close(mw_fd);

	return 0;
};