#include "main.h"

#include "stm32l100c_discovery.h"

#include "ssd1306.h"

#include "config.h"

// USB includes

#include "hw_config.h"

#include "usb_lib.h"

#include "usb_desc.h"

#include "usb_pwr.h"

#include "stringhelpers.h"

// TODO: Grab buttonpresses with interrupts

// TODO: Eliminate screen buffer since we aren't using it...

// USB Supporting Vars

extern __IO uint8_t Receive_Buffer[64];

extern __IO  uint32_t Receive_length ;

extern __IO  uint32_t length ;

uint8_t Send_Buffer[64];

uint32_t packet_sent=1;

uint32_t packet_receive=1;

// Globalish setting vars

uint8_t boottobrew = 0;

#define WINDUP_GUARD_GAIN 100

uint16_t windup_guard = WINDUP_GUARD_GAIN;

uint16_t k_p = 1;

uint16_t k_i = 1;

uint16_t k_d = 1;

// State definition

enum state {

    STATE_IDLE = 0,

    STATE_SETP,

    STATE_SETI,

    STATE_SETD,

    STATE_SETWINDUP,

    STATE_SETBOOTTOBREW,

    STATE_PREHEAT_BREW,

    STATE_MAINTAIN_BREW,

    STATE_PREHEAT_STEAM,

    STATE_MAINTAIN_STEAM,

};

static __IO uint32_t TimingDelay;

// Move to header file

void init_gpio();

void init_spi();

void process();

void machine();

void delay(__IO uint32_t nTime);

void restore_settings();

void save_settings();

int main(void)

{

    // Init clocks

    SystemInit();

    // Init GPIO

    init_gpio();

    // Init USB

    //Set_USBClock();

    //USB_Interrupts_Config();

    //USB_Init();

    // Turn on power LED

    GPIO_SetBits(LED_POWER);

    // TODO: Awesome pwm of power LED (TIM4_CH4 or TIM11_CH1)

    // Configure 1ms SysTick (change if more temporal resolution needed) 

    RCC_ClocksTypeDef RCC_Clocks;

    RCC_GetClocksFreq(&RCC_Clocks);

    SysTick_Config(RCC_Clocks.HCLK_Frequency / 1000);

    // Init SPI busses

    init_spi();

    // Init OLED over SPI

    ssd1306_Init();

    ssd1306_clearscreen();

    // Startup screen 

    ssd1306_DrawString("therm v0.1", 1, 40);

    ssd1306_DrawString("protofusion.org/therm", 3, 0);

    delay(1500);

    ssd1306_clearscreen();

    restore_settings();

    GPIO_ResetBits(LED_STAT);

    // Main loop

    while(1)

    {

        // Process sensor inputs

        process();

        // Run state machine

        machine(); 

    }

}

// Read temperature and update global temp vars

int16_t temp = 0;

uint8_t temp_frac = 0;

void update_temp() {

    // Assert CS

    GPIO_ResetBits(MAX_CS);

    delay(1);

    // This may not clock at all... might need to send 16 bits first

    SPI_I2S_SendData(SPI2, 0xAAAA); // send dummy data

    //SPI_I2S_SendData(SPI2, 0xAA); // send dummy data

    uint16_t temp_pre = SPI_I2S_ReceiveData(SPI2);

    if(temp_pre & 0b0000000000000010) {

        ssd1306_DrawString("Fatal Error", 2, 35);

    }

    else if(temp_pre & 0b0000000000000001) {

        ssd1306_DrawString("Error: No TC", 2, 40);

        temp = 0;

        temp_frac = 0;

    }

    else 

    {

        uint8_t sign = temp >> 15;// top bit is sign

        temp_pre = temp_pre >> 2; // Drop 2 lowest bits

        temp_frac = temp_pre & 0b11; // get fractional part

        temp_frac *= 25; // each bit is .25 a degree, up to fixed point

        temp_pre = temp_pre >> 2; // Drop 2 fractional bits 

        if(sign) {

            temp = -temp_pre;

        }

    // Every 200ms, set the SSR on unless output is 0

    if((ticks - last_ssr_on > SSR_PERIOD))

    {

        if(pid_enabled) 

        {

            // Get ssr output for next time

            int16_t power_percent = update_pid(k_p, k_i, k_d, temp, temp_frac, setpoint);

            //power-percent is 0-1000

            ssr_output = power_percent; //(((uint32_t)SSR_PERIOD * (uint32_t)10 * (uint32_t)100) * power_percent) / (uint32_t)1000000;

        }

        else 

        {

            ssr_output = 0;

        }

        // Only support heating (ssr_output > 0) right now

        if(ssr_output > 0) {

            char tempstr[6];

            itoa(ssr_output, tempstr);

            ssd1306_DrawString("#=", 2, 45);

            ssd1306_DrawString("    ", 2, 57);

            ssd1306_DrawString(tempstr, 2, 57);

            GPIO_SetBits(LED_STAT);

            last_ssr_on = ticks;

        }

    }

    // Kill SSR after elapsed period less than SSR_PERIOD 

    if(ticks - last_ssr_on > ssr_output)

    {

        GPIO_ResetBits(LED_STAT);

    }

}

void draw_setpoint() {

    char tempstr[3];

    itoa_fp(temp, temp_frac, tempstr);

    //ssd1306_DrawString("        ", 3, 40);

    ssd1306_DrawString(tempstr, 3, 40);

    ssd1306_DrawString("-> ", 3, 80);

    itoa(setpoint, tempstr);

    ssd1306_DrawString("    ", 3, 95);

    ssd1306_DrawString(tempstr, 3, 95);

}

uint8_t goto_mode = 2;

// State machine

uint8_t sw_btn_last = 0;

uint8_t sw_up_last = 0;

uint8_t sw_down_last = 0;

uint8_t sw_left_last = 0;

uint8_t sw_right_last = 0;

#define SW_BTN_PRESSED (sw_btn_last == 0 && sw_btn == 1) // rising edge on buttonpress

#define SW_UP_PRESSED (sw_up_last == 0 && sw_up == 1)

#define SW_DOWN_PRESSED (sw_down_last == 0 && sw_down == 1)

#define SW_LEFT_PRESSED (sw_left_last == 0 && sw_left == 1)

#define SW_RIGHT_PRESSED (sw_right_last == 0 && sw_right == 1)

/*

 * uint8_t boottobrew = 0;

#define WINDUP_GUARD_GAIN 100

uint16_t windup_guard = WINDUP_GUARD_GAIN;

uint16_t k_p = 1;

uint16_t k_i = 1;

uint16_t k_d = 1;*/

#define EEPROM_ADDR_WINDUP_GUARD 	0x0808001C

#define EEPROM_ADDR_BOOTTOBREW		0x08080020

#define EEPROM_ADDR_K_P			0x8080024

#define EEPROM_ADDR_K_I			0x8080028

#define EEPROM_ADDR_K_D			0x808002C

void save_settings()

{

    DATA_EEPROM_Unlock();

    // Try programming a word at an address divisible by 4

    DATA_EEPROM_ProgramWord(EEPROM_ADDR_BOOTTOBREW, boottobrew);

    DATA_EEPROM_ProgramWord(EEPROM_ADDR_WINDUP_GUARD, windup_guard);

    DATA_EEPROM_ProgramWord(EEPROM_ADDR_K_P, k_p);

    DATA_EEPROM_ProgramWord(EEPROM_ADDR_K_I, k_i);

    DATA_EEPROM_ProgramWord(EEPROM_ADDR_K_D, k_d);

    DATA_EEPROM_Lock();

}

void restore_settings()

{

    DATA_EEPROM_Unlock();

    while(FLASH_GetStatus()==FLASH_BUSY);

    boottobrew = (*(__IO uint32_t*)EEPROM_ADDR_BOOTTOBREW);

    while(FLASH_GetStatus()==FLASH_BUSY);

    windup_guard = (*(__IO uint32_t*)EEPROM_ADDR_WINDUP_GUARD);

    while(FLASH_GetStatus()==FLASH_BUSY);

    k_p = (*(__IO uint32_t*)EEPROM_ADDR_K_P);

    while(FLASH_GetStatus()==FLASH_BUSY);

    k_i = (*(__IO uint32_t*)EEPROM_ADDR_K_I);

    while(FLASH_GetStatus()==FLASH_BUSY);

    k_d = (*(__IO uint32_t*)EEPROM_ADDR_K_D);

    DATA_EEPROM_Lock();

}

void machine()

{

    uint8_t last_state = state;

    uint8_t sw_btn = !GPIO_ReadInputDataBit(SW_BTN);

    uint8_t sw_up = !GPIO_ReadInputDataBit(SW_UP);

    uint8_t sw_down = !GPIO_ReadInputDataBit(SW_DOWN);

    uint8_t sw_left = !GPIO_ReadInputDataBit(SW_LEFT);

    uint8_t sw_right = !GPIO_ReadInputDataBit(SW_RIGHT);

    switch(state)

    {

        // Idle state

        case STATE_IDLE:

        {

            // Write text to OLED

            // [ therm :: idle ]

            ssd1306_DrawString("therm :: idle ", 0, 40);

            pid_enabled = 0;

            char tempstr[6];

            itoa_fp(temp, temp_frac, tempstr);

            ssd1306_DrawString("Temp: ", 3, 40);

            ssd1306_DrawString("    ", 3, 72);

            ssd1306_DrawString(tempstr, 3, 72);

            ssd1306_drawlogo();

            switch(goto_mode) {

                case 2:

                {

                    ssd1306_DrawString("-> brew     ", 1, 40);

                } break;

                case 1:

                {

                    ssd1306_DrawString("-> setup    ", 1, 40);

                } break;

                case 0:

                {

                    ssd1306_DrawString("-> reset    ", 1, 40);

                } break;

            }

            // Button handler