/*********************************************************************************
 *      Copyright:  (C) 2019 LingYun IoT System Studio
 *                  All rights reserved.
 *
 *       Filename:  gpio.c
 *    Description:  This file is GPIO input/output functions
 *
 *        Version:  1.0.0(2019年06月24日)
 *         Author:  Guo Wenxue <guowenxue@gmail.com>
 *      ChangeLog:  1, Release initial version on "2019年06月24日 23时46分47秒"
 *
 ********************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <dirent.h>
#include <string.h>
#include <time.h>
#include <errno.h>

#include "logger.h"
#include "util_proc.h"
#include "gpio.h"

#define RPI_GPIONAME        "gpiochip0"

static struct gpiod_chip    *s_chip;
static gpio_t               *s_gpio = NULL;

int gpio_init(gpio_t *gpio)
{
    int                 i;
    int                 rv;

    s_gpio = gpio;

    if( !gpio )
    {
        log_error("Invalid input arguments $gpio\n");
        return -1;
    }


    if( !gpio->incnt && !gpio->outcnt )
    {
        log_warn("WARNNING: No GPIO pins configured\n");
        return 0;
    }

    /*  gpiod open chip */
    s_chip = gpiod_chip_open_by_name(RPI_GPIONAME);
    if( !s_chip )
    {
        log_error("gpiod open chip failure, maybe you need running as root\n");
        return -2;
    }
    log_info("gpiod initialise open chip ok\n");


    /*  gpiod request all output pins */
    for(i=0; i<gpio->outcnt; i++)
    {
        gpio->output[i].line = gpiod_chip_get_line(s_chip, gpio->output[i].pin);
        if( !gpio->output[i].line )
        {
            log_error("gpiod get line for '%s' pin[#%d] failure\n", gpio->output[i].name, gpio->output[i].pin );
            return -2;
        }

        if( gpiod_line_request_output(gpio->output[i].line, gpio->output[i].name, !gpio->output[i].active_level) < 0 )
        {
            log_error("gpiod request '%s' pin[#%d] output failure: %s\n", gpio->output[i].name, gpio->output[i].pin, strerror(errno));
        }
        else
        {
            log_info("gpiod request '%s' pin[#%d] output ok\n", gpio->output[i].name, gpio->output[i].pin);
        }
    }


    /*  gpiod request all input pins */
    for(i=0; i<gpio->incnt; i++)
    {
        gpio->input[i].line = gpiod_chip_get_line(s_chip, gpio->input[i].pin);
        if( !gpio->input[i].line )
        {
            log_error("gpiod get line for '%s' pin[#%d] failure\n", gpio->input[i].name, gpio->input[i].pin );
            return -2;
        }

        if( gpio->output[i].active_level )
            rv = gpiod_line_request_rising_edge_events(gpio->input[i].line, gpio->input[i].name) ;
        else
            rv = gpiod_line_request_falling_edge_events(gpio->input[i].line, gpio->input[i].name) ;

        if( rv < 0 )
        {
            log_error("gpiod request '%s' pin[#%d] event edge [%s] failure: %s\n",
                    gpio->input[i].name, gpio->input[i].pin, gpio->output[i].active_level?"rising":"falling", strerror(errno));
        }
        else
        {
            log_info("gpiod request '%s' pin[#%d] event edge [%s] ok\n",
                    gpio->input[i].name, gpio->input[i].pin, gpio->output[i].active_level?"rising":"falling");
        }
    }

    return 0;
}


void gpio_term(void)
{
    int              i;

    log_info("start teriminated GPIO\n");

    if( !s_gpio->incnt && !s_gpio->outcnt )
    {
        return ;
    }


    for(i=0; i<s_gpio->outcnt; i++)
    {
        gpiod_line_release(s_gpio->output[i].line);
    }


    for(i=0; i<s_gpio->incnt; i++)
    {
        gpiod_line_release(s_gpio->input[i].line);
    }

    gpiod_chip_close(s_chip);
}

void gpio_out(char *name, char *cmd)
{
    int              i;
    int              found = 0;

    for( i=0; i<s_gpio->outcnt; i++ )
    {
        if( !strncasecmp(s_gpio->output[i].name, name, strlen(name)))
        {
            found = 1;
            break;
        }
    }

    if( !found )
    {
        log_error("GPIO output for '%s' pin not found\n", name);
        return ;
    }

    if( strstr(cmd, "on") )
    {
        gpiod_line_set_value(s_gpio->output[i].line, s_gpio->output[i].active_level);
    }
    else if( strstr(cmd, "off") )
    {
        gpiod_line_set_value(s_gpio->output[i].line, !s_gpio->output[i].active_level);
    }

    return ;
}


void *light_on_worker(void *arg)
{
    int                      i;
    int                      found = 0;
    char                    *name = (char *)arg;
    gpio_info_t             *gpiout;

    if( !name )
    {
        log_error("Invalid input arugment\n");
        return NULL;
    }

    if( s_gpio->light_intval <= 0 )
    {
        log_error("Invalid light_intval value[%d] in configure file\n", s_gpio->light_intval);
        return NULL;
    }

    for(i=0; i<s_gpio->outcnt; i++)
    {
        if( strstr(s_gpio->output[i].name, name) )
        {
            gpiout = &(s_gpio->output[i]);
            found = 1;
        }
    }

    if( !found )
    {
        log_error("Light '%s' not found\n", name);
        return NULL;
    }

    log_info("Trun on %s for [%d] seconds\n", gpiout->name, s_gpio->light_intval);

    gpio_out(gpiout->name, "on");
    sleep(s_gpio->light_intval);
    gpio_out(gpiout->name, "off");

    return NULL;
}

/* Return value: 0(LOW): Nobody detected, !0: indoor or hallway detected */
int infrared_detect(void)
{
    int                      i;
    int                      rv = 0;
    int                      res = 0;

    struct gpiod_line_event  ev;
    struct gpiod_line_bulk   bulk, event_bulk;
    struct gpiod_line       *line;

    int                      num_lines = 0;


    gpiod_line_bulk_init(&bulk);

    for(i=0; i<s_gpio->incnt; i++)
    {
        if( strstr(s_gpio->input[i].name, "infrared"))
        {
            gpiod_line_bulk_add(&bulk, s_gpio->input[i].line);
            num_lines ++;
        }
    }

    if( !num_lines )
    {
        log_error("No infrared detect gpiod lines found\n");
        return 0;
    }

    log_debug("infrared start detect event now...\n");
    rv = gpiod_line_event_wait_bulk(&bulk, NULL, &event_bulk);
    if( rv <= 0 )
    {
        log_error("infrared gpiod line wait[%s] event failure!\n", s_gpio->input[i].name);
        return 0;
    }

    for (i=0; i<num_lines; i++)
    {
        line = gpiod_line_bulk_get_line(&event_bulk, 0);

        /* must call this function to  clear the event  */
        rv = gpiod_line_event_read(line, &ev);
        if( rv < 0)
        {
            log_error("gpiod_line_event_read get failure\n");
            break;
        }

        for(i=0; i<s_gpio->incnt; i++)
        {
            if(line == s_gpio->input[i].line)
            {
                if( s_gpio->input[i].active_level != gpiod_line_get_value(line) )
                {
                    //log_debug("infrared '%s' detect get wrong power level\n", s_gpio->input[i].name);
                    continue;
                }

                if( strstr(s_gpio->input[i].name, "indoor") )
                {
                    log_debug("indoor infrared gpiod wait get event.\n", s_gpio->input[i].name);
                    res |= FLAG_INFRARED_INDOOR;
                }
                else if( strstr(s_gpio->input[i].name, "hallway") )
                {
                    log_debug("hallway infrared gpiod wait get event.\n", s_gpio->input[i].name);
                    res |= FLAG_INFRARED_HALLWAY;
                }
            }
        }
    }

    return res;
}