//

// WSPRHAB: Minimal high-altitude balloon tracker with WSPR telemetry

//

#include "stm32f0xx_hal.h"

#include "adc.h"

#include "system.h"

#include "i2c.h"

#include "uart.h"

#include "gpio.h"

#include "wspr.h"

#include "rtc.h"

#include "gps.h"

#include "config.h"

// We have access to the 1PPS pin of the gps... could have trim routine for internal oscillator based on this when we have a fix

// Probable wake up 1 minute early -- 0.45min possible +/- on wakeup time with 15min sync intervals

// TODO: Add JT9 message with more grid locator digits + altitude + vbatt + temp

// MSG13charmax:

// 	X: gridloc

//  Y: altitude

//  Z: temperature

//  KD8TDF XXYYZZ // could use alt callsign thing

enum _state

{

    SYSTEM_IDLE = 0, // awaiting RTC interrupt for wakeup TODO wake up before scheduled time to get fix?

    SYSTEM_GPSACQ, // RTC interrupted

    SYSTEM_WSPRTX, // Wait for timeslot and actually transmit the message

};

static void __calc_gridloc(char *dst, double lat, double lon);

static void ledpulse(void);

uint32_t statled_ontime = 0;

int main(void)

{

    HAL_Init();

    HAL_Delay(1000); // startup delay before infinisleep

    sysclk_init();

    gpio_init();

    rtc_init();

    adc_init();

    wspr_init();

    uint32_t led_timer = HAL_GetTick();

    led_blink(4);

    uint16_t blink_rate = BLINK_FAST;

//    uint8_t state = SYSTEM_GPSACQ;

//DEBUG:

    uint8_t state = SYSTEM_IDLE;

    uint32_t gps_polltimer = 0;

    uint32_t fix_acq_starttime = 0;

    uint32_t nextwspr_time = 0;

    uint8_t nextwspr_time_valid = 0;

    uint32_t last_wspr_tx_time = 0;

    uint8_t packet_type = 0;

    // Transmit pilot tone to test TX on bootup

    HAL_Delay(1000);

    wspr_pilot_tone();

    adc_stop();

    HAL_Delay(1000);

    while (1)

    {

    	// TODO: Disable GPIO port clocking when not needed!

    	// Every 10 minutes, wake up and try to wspr

    	if(state == SYSTEM_IDLE && (HAL_GetTick() - last_wspr_tx_time > 60000 * 10))

    	{

    		state = SYSTEM_GPSACQ;

    	}

        // Update fix status every 2 seconds, only if the GPS is powered on

        if(HAL_GetTick() - gps_polltimer > 2000)

        {

            if(gps_ison())

            {

            	gps_update_data();

            	// If odd minute

            	if(gps_getdata()->minute % 2)

            	{

            		// Wait until even minute plus one second, coming soon

            		nextwspr_time = HAL_GetTick() + (60000 - (gps_getdata()->second * 1000));

                    nextwspr_time_valid = 1;

            	}

            	// If even minute

            	else

            	{

            		// Wait until odd minute, one minute and some change away

            		nextwspr_time = HAL_GetTick() + 60000 + (60000 - (gps_getdata()->second * 1000));

                    nextwspr_time_valid = 1;

            	}

            }

            gps_polltimer = HAL_GetTick();

        }

        switch(state)

        {

            // Idling: sleep and wait for RTC timeslot trigger

            case SYSTEM_IDLE:

            {

                blink_rate = BLINK_SLOW;

                // Actually sleep for real: disable systick and sleep until RTC interrupt

//                HAL_SuspendTick();

                // Enter sleep mode: wait for interrupt

                //HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

        		HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);

                // This is hopefully the only timer that needs to stay alive in idle mode

 //               last_wspr_tx_time += 0; // move this timer forward based on sleep length

 //               HAL_ResumeTick();

                // TODO: Eventually use GPS time to calibrate the RTC maybe

            } break;

            // Attempt to acquire GPS fix

            case SYSTEM_GPSACQ:

            {

                blink_rate = BLINK_FAST;

                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                if(!gps_ison())

                {

                	fix_acq_starttime = HAL_GetTick();

                    gps_poweron(); // power on and initialize GPS module

                }

                // TODO: Move GPS processing into here from above!

                // If 3d fix with a decent enough precision

                if( ((gps_getdata()->fixtype == 2) || (gps_getdata()->fixtype == 3)) && gps_getdata()->pdop < 10 && nextwspr_time_valid == 1)

                {

                    // Disable GPS module

                    gps_poweroff();

                    // TODO: Set RTC from GPS time

                    // TODO: Set RTC for countdown to next transmission timeslot!

                    // TODO: Set wspr countdown timer for this transmission!

                    fix_acq_starttime = 0;

                    state = SYSTEM_WSPRTX;

                    adc_start();

                }

                // If no decent fix in 3 minutes

                else if(HAL_GetTick() - fix_acq_starttime > 60000 * 3)

                {

                	// Flash error code and go to idle, try again next time

                	led_blink(4);

                    gps_poweroff();

                    fix_acq_starttime = 0;

                    last_wspr_tx_time = HAL_GetTick(); // repeat acq/tx cycle after big time delay

                	state = SYSTEM_IDLE;

                }

            } break;

            // Wait for wspr timeslot and start transmitting

            case SYSTEM_WSPRTX:

            {

            	blink_rate = BLINK_MED;

                // Wait for wspr countdown timer to expire and go to tx

//                if(timeout_expired)

//                {

            	// If we're after the minute but not more than 2s after the minute, start tx

            	if(HAL_GetTick() >= nextwspr_time)

            	{

            		if(HAL_GetTick() < nextwspr_time + 2000)

            		{

            			volatile double latitude_flt = (double)gps_getdata()->latitude / 10000000.0;

            			volatile double longitude_flt = (double)gps_getdata()->longitude / 10000000.0;

            			volatile uint8_t grid_locator[7];

            			__calc_gridloc(grid_locator, latitude_flt, longitude_flt);

                        // TODO: Switch between alternate and standard packet

						wspr_transmit(grid_locator, packet_type);

                        packet_type = !packet_type; // alternate packet type

						last_wspr_tx_time = HAL_GetTick();

						state = SYSTEM_IDLE;

                        adc_stop();

            		}

            		else

            		{

            			// Window was missed, go back to idle, and try again after time delay

						last_wspr_tx_time = HAL_GetTick();

            			state = SYSTEM_IDLE;

                        adc_stop();

            		}

                    nextwspr_time_valid = 0; // invalidate wspr time

                }

            	else

            	{

                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);

            	}

                // Schedule next wakeup (maybe 2mins prior to timeslot if no osc trim)

                // Next wakeup should enter SYSTEM_GPSACQ state...

            } break;

        }

		#ifndef LED_DISABLE

			if(HAL_GetTick() - led_timer > blink_rate)

			{

				ledpulse();

				led_timer = HAL_GetTick();

			}

			if(statled_ontime && HAL_GetTick() - statled_ontime > 10)

			{

				HAL_GPIO_WritePin(LED_BLUE, 0);

				statled_ontime = 0;

			}

		#endif

    }

}

static void ledpulse(void)

{

    HAL_GPIO_WritePin(LED_BLUE, 1);

	statled_ontime = HAL_GetTick();

}

static void __calc_gridloc(char *dst, double lat, double lon)

{

	int o1, o2, o3;

	int a1, a2, a3;

	double remainder;

	// longitude

	remainder = lon + 180.0;

	o1 = (int)(remainder / 20.0);

	remainder = remainder - (double)o1 * 20.0;

	o2 = (int)(remainder / 2.0);

	remainder = remainder - 2.0 * (double)o2;

	o3 = (int)(12.0 * remainder);

	// latitude

	remainder = lat + 90.0;

	a1 = (int)(remainder / 10.0);

	remainder = remainder - (double)a1 * 10.0;

	a2 = (int)(remainder);

	remainder = remainder - (double)a2;

	a3 = (int)(24.0 * remainder);

	dst[0] = (char)o1 + 'A';

	dst[1] = (char)a1 + 'A';

	dst[2] = (char)o2 + '0';

	dst[3] = (char)a2 + '0';

	dst[4] = (char)o3 + 'A';

	dst[5] = (char)a3 + 'A';

	dst[6] = (char)0;

}