/***************************************************************************
 *   Copyright (C) 02/2012 by Olaf Rempel                                  *
 *   razzor@kopf-tisch.de                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include <sys/socket.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>

#include "event.h"
#include "lcd.h"
#include "logging.h"
#include "pic.h"

struct picdev {
	int fd;
	struct termios oldtio;

	int fan_speed;
	int fan_error;
	int temperature;

	struct event_fd *read_event;
};

static int pic_close_device(struct picdev *dev)
{
	tcsetattr(dev->fd, TCSANOW, &dev->oldtio);
	close(dev->fd);
	return 0;
}

static int pic_open_device(struct picdev *dev, const char *device)
{
	dev->fd = open(device, O_RDWR | O_NOCTTY);
	if (dev->fd < 0) {
		log_print(LOG_ERROR, "%s(): failed to open '%s'", __FUNCTION__, device);
		return -1;
	}

	if (fcntl(dev->fd, F_SETFD, FD_CLOEXEC) < 0) {
		log_print(LOG_ERROR, "%s(): fcntl(FD_CLOEXEC)", __FUNCTION__);
		close(dev->fd);
		return -1;
	}

	tcgetattr(dev->fd, &dev->oldtio);

	struct termios newtio;
	memset(&newtio, 0, sizeof(newtio));
	newtio.c_iflag |= IGNBRK;
	newtio.c_lflag &= ~(ISIG | ICANON | ECHO);
	newtio.c_cflag = B19200 | CS8 | CLOCAL | CREAD;
	newtio.c_cc[VMIN] = 1;
	newtio.c_cc[VTIME] = 0;
	cfsetospeed(&newtio, B19200);
	cfsetispeed(&newtio, B19200);

	int err = tcsetattr(dev->fd, TCSAFLUSH, &newtio);
	if (err < 0) {
		log_print(LOG_ERROR, "%s(): failed to set termios", __FUNCTION__);
		close(dev->fd);
		return -1;
	}

	return 0;
}

int pic_set_fanspeed(struct picdev *dev, char value)
{
	if (value < PIC_CMD_FANSPEED_0 || value > PIC_CMD_FANSPEED_5)
		return -1;

	dev->fan_speed = value - PIC_CMD_FANSPEED_0;

	write(dev->fd, &value, 1);
	return 0;
}

int pic_set_buzzer(struct picdev *dev, char value)
{
	if (value < PIC_CMD_BUZZ_SHORT || value > PIC_CMD_BUZZ_LONG)
		return -1;

	write(dev->fd, &value, 1);
	return 0;
}

int pic_set_status_led(struct picdev *dev, char value)
{
	if (value < PIC_CMD_STATUSLED_RED_2HZ || value > PIC_CMD_STATUSLED_REDGREEN_1HZ)
		return -1;

	write(dev->fd, &value, 1);
	return 0;
}

int pic_set_usb_led(struct picdev *dev, char value)
{
	if (value < PIC_CMD_USBLED_ON || value > PIC_CMD_USBLED_OFF)
		return -1;

	write(dev->fd, &value, 1);
	return 0;
}

static int pic_read_cb(int fd, void *privdata)
{
	struct picdev *dev = (struct picdev *)privdata;

	unsigned char event;
	int len = read(dev->fd, &event, 1);
	if (len < 0)
		return -1;

	switch (event)
	{
	case PIC_EVENT_FAN1_ERR:
		pic_set_buzzer(dev, PIC_CMD_BUZZ_SHORT);
		dev->fan_error = 1;
		break;

	case PIC_EVENT_FAN1_OK:
		dev->fan_error = 0;
		break;

	case PIC_EVENT_FAN2_ERR:
	case PIC_EVENT_FAN2_OK:
		break;

	case PIC_EVENT_TEMP_RANGE_MIN ... PIC_EVENT_TEMP_RANGE_MAX:
		dev->temperature = event - 128;
		break;

	case PIC_EVENT_TEMP_WARN:
		pic_set_buzzer(dev, PIC_CMD_BUZZ_SHORT);
		dev->temperature = 75;
		break;

	case PIC_EVENT_TEMP_CRIT:
		dev->temperature = 80;
		break;

	default:
		log_print(LOG_DEBUG, "%s(): unknown event 0x%02x", __FUNCTION__, event);
		break;
	}

	return 0;
}

static int lcdpage_case(struct lcddev *lcd, int event, void *privdata)
{
	struct picdev *dev = (struct picdev *)privdata;

	switch (event) {
		case LCDPAGE_EVENT_BUTTON1:
			return LCDPAGE_COMMAND_NEXT;

		case LCDPAGE_EVENT_BUTTON2:
		{
			int fan_speed = PIC_CMD_FANSPEED_0 + dev->fan_speed +1;

			if (fan_speed > PIC_CMD_FANSPEED_5)
				fan_speed = PIC_CMD_FANSPEED_0;

			pic_set_fanspeed(dev, fan_speed);
			lcd_set_backlight(lcd, 1);
			break;
		}

		case LCDPAGE_EVENT_ENTER:
			lcd_set_backlight(lcd, 1);
			break;

		case LCDPAGE_EVENT_BACKLIGHT:
		case LCDPAGE_EVENT_EXIT:
			return 0;

		default:
			break;
	}

	char line1_ok[] = "FAN(OK):  TEMP:";
	char line1_err[] = "FAN(ERR): TEMP:";
	char line2[20];

	snprintf(line2, sizeof(line2), "[     ]   %02d C ", dev->temperature);

	int i;
	for (i = 1; i <= dev->fan_speed; i++) {
		line2[i] = '#';
	}

	lcd_setlines(lcd, (dev->fan_error ? line1_err : line1_ok), line2);
	return 1000;
}

struct picdev * pic_open(const char *devicename, struct lcddev *lcd)
{
	struct picdev *dev = malloc(sizeof(struct picdev));
	if (dev == NULL) {
		log_print(LOG_ERROR, "%s(): out of memory", __FUNCTION__);
		return NULL;
	}

	memset(dev, 0, sizeof(struct picdev));

	if (pic_open_device(dev, devicename) < 0) {
		free(dev);
		return NULL;
	}

	dev->read_event = event_add_readfd(NULL, dev->fd, pic_read_cb, dev);

	if (lcd != NULL) {
		lcd_addpage_cb(lcd, 190, lcdpage_case, dev);
	}

	pic_set_fanspeed(dev, PIC_CMD_FANSPEED_1);
	pic_set_status_led(dev, PIC_CMD_STATUSLED_GREENON);

	return dev;
}

void pic_close(struct picdev *dev)
{
	if (dev->read_event != NULL) {
		event_remove_fd(dev->read_event);
		dev->read_event = NULL;
	}

	pic_close_device(dev);

	free(dev);
}