#include "main.h"

#include "stm32l100c_discovery.h"

#include "ssd1306.h"

#include "config.h"

#include "eeprom_min.h"

#include "gpio.h"

#include "spi.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

// 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;

uint16_t windup_guard = 1;

uint16_t k_p = 1;

uint16_t k_i = 1;

uint16_t k_d = 1;

// ISR ticks var

volatile uint32_t ticks = 0;

int16_t setpoint_brew = 0;

int16_t setpoint_steam = 0;

// 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,

};

uint8_t state = STATE_IDLE;

static __IO uint32_t TimingDelay;

// Move to header file

void process();

void machine();

void restore_settings();

void save_settings();

void save_setpoints();

int main(void)

{

    // Init clocks

    SystemInit();

    // Init GPIO

    init_gpio();

    // 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();

    // Check for problems on startup

    if(clock_fail) {

    }

    // Init USB

    //Set_System(); // hw_config.h

    Set_USBClock();

    USB_Interrupts_Config();

    USB_Init();

    //SYSCFG_USBPuCmd(ENABLE);

    //PowerOn();

    // Startup screen 

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

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

    delay(1500);

    ssd1306_clearscreen();

    restore_settings();

    if(boottobrew)

      state = STATE_PREHEAT_BREW; // Go to brew instead of idle if configured thusly

    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;

        }

        else {

            temp = temp_pre;

        }

    }

    // Deassert CS

    delay(1);

    GPIO_SetBits(MAX_CS);

}

// PID implementation

// TODO: Make struct that has the last_temp and i_state in it, pass by ref. Make struct that has other input values maybe.

int16_t last_pid_temp = 0;

uint8_t last_pid_temp_frac = 0;

int16_t i_state = 0;

int16_t update_pid(uint16_t k_p, uint16_t k_i, uint16_t k_d, int16_t temp, uint8_t temp_frac, int16_t setpoint) 

{

  // Calculate instantaneous error

  int16_t error = (int16_t)setpoint - (int16_t)temp; // TODO: Use fixed point fraction

  // Proportional component

  int16_t p_term = k_p * error;

  // Error accumulator (integrator)

  i_state += error;

  // Calculate integral term with windup guard 

  if (i_state > windup_guard_res) 

    i_state = windup_guard_res;

  else if (i_state < -windup_guard_res) 

    i_state = -windup_guard_res;

  int16_t i_term = k_i * i_state;

  // Calculate differential term (slope since last iteration)

  int16_t d_term = (k_d * (temp - last_pid_temp));

  // Save temperature for next iteration

  last_pid_temp = temp;

  last_pid_temp_frac = temp_frac;

  int16_t result = p_term + i_term - d_term;

  // Put out tenths of percent, 0-1000. 

  if(result > 1000)

    result = 1000;

  else if(result < -1000)

    result = -1000;

  // Return feedback

  return result;

}

uint32_t last_ssr_on = 0;

uint32_t last_led = 0;

int32_t setpoint = 0;

int16_t ssr_output = 0; // Duty cycle of ssr, 0 to SSR_PERIOD 

uint8_t pid_enabled = 0;

// Process things

void process()

{

    update_temp(); // Read MAX31855

    // TODO: Add calibration offset (linear)

    if(ticks - last_led > 400) 

    {

        GPIO_ToggleBits(LED_POWER);

        last_led = ticks;

    }

    // 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);

            GPIO_SetBits(SSR_PIN);

            last_ssr_on = ticks;

        }

    }

    // Kill SSR after elapsed period less than SSR_PERIOD 

    if(ticks - last_ssr_on > ssr_output || ssr_output == 0)

    {

        GPIO_ResetBits(LED_STAT);

        GPIO_ResetBits(SSR_PIN);

    }

}

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);

}

// 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)

void save_settings()

{

   Minimal_EEPROM_Unlock();

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

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_BOOTTOBREW, boottobrew);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_WINDUP_GUARD, windup_guard);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_K_P, k_p);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_K_I, k_i);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_K_D, k_d);

    Minimal_EEPROM_Lock();

}

void save_setpoints()

{

    Minimal_EEPROM_Unlock();

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_BREWTEMP, setpoint_brew);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_STEAMTEMP, setpoint_steam); 

    Minimal_EEPROM_Lock();

}

// TODO: Make a struct that has all settings in it. Pass by ref to this func in a library.

void restore_settings()

{

    Minimal_EEPROM_Unlock();

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

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

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

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

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

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

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

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

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

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

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    setpoint_brew = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_BREWTEMP));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    setpoint_steam = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_STEAMTEMP));    

    Minimal_EEPROM_Lock();

}

int16_t last_temp = 21245;

void machine()

{

    uint8_t last_state = state;

    uint8_t temp_changed = temp != last_temp;

    last_temp = temp;

    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;

            if(temp_changed) {

                char tempstr[6];

                itoa_fp(temp, temp_frac, tempstr);

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

                ssd1306_DrawString("    ", 3, 72);

                ssd1306_DrawString(tempstr, 3, 72);

            }

    {0x30,0x48,0x45,0x40,0x20},         //   (100)  ? - 0x00BF Inverted Question Mark

    {0x22,0x14,0x08,0x14,0x22},         //   (101)  x - 0x00D7 Multiplcation Sign

    {0x08,0x08,0x2A,0x08,0x08},         //   (102)  + - 0x00F7 Division Sign

    {0x18,0x14,0x08,0x14,0x0C},         //   (103)    - 0x221E Infinity

    {0x44,0x4A,0x4A,0x51,0x51},         //   (104)  < - 0x2264 Less-Than or Equal to

    {0x51,0x51,0x4A,0x4A,0x44},         //   (105)  > - 0x2265 Greater-Than or Equal to

    {0x54,0x14,0x64,0x08,0x70},         //   (106)  .: - RF Symbol

    {0x70,0x7C,0x72,0x7C,0x70},         //   (107)  ^ - Lock symbol

    {0x70,0x5C,0x52,0x54,0x70},         //   (108)  / - Unlock symbol

    {0x0C,0x1E,0x3C,0x1E,0x0C},         //   (109)  <3 - Heart Symbol

    {0x18,0x22,0xFF,0x12,0x0C},         //   (110)  U - USB Symbol

};

void setStartPage(unsigned char d)

{

    WriteCommand(0xB0|d);       // Set Page Start Address for Page Addressing Mode

                                // Default => 0xB0 (0x00)

}

/* Below are functions used to configure the OLED */

void setStartColumn(unsigned char d)

{

    WriteCommand(0x00+d%16);    // Set Lower Column Start Address for Page Addressing Mode

    WriteCommand(0x10+d/16);    // Set Higher Column Start Address for Page Addressing Mode

                                // Default => 0x10

}

const uint8_t row[4][32] = { 

	{0x00,0x00,0x01,0x03,0x07,0x0F,0x1E,0x3C,0x3C,0x7C,0x7C,0x7C,0xFC,0xFF,0xFF,0xFC,0xFC,0xFC,0xFC,0xFF,0x7F,0x7F,0x7F,0x3C,0x3C,0x1C,0x0C,0x06,0x03,0x01,0x00,0x00},

	{0x0F,0x7F,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x3F,0x3F,0x7F,0xFF,0xFF,0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0xFF,0xFF,0x7F,0x0F},

	{0xF0,0xFE,0xFF,0xFF,0xFF,0xC7,0x00,0x00,0x00,0x00,0x87,0xC7,0xC7,0xFF,0xFF,0x00,0x00,0x00,0x00,0x87,0x87,0xC7,0xC3,0x03,0x07,0x07,0x0F,0x7F,0xFF,0xFF,0xFE,0xF0},

	{0x00,0x00,0x80,0xC0,0xE0,0xF0,0xF8,0xFC,0xFC,0xFE,0xFE,0xFE,0xFF,0xFF,0xFF,0x1F,0x1F,0x1F,0x1F,0xFF,0xFE,0xFE,0xFE,0xFC,0xFC,0xF8,0xF0,0xE0,0xC0,0x80,0x00,0x00},

};

void ssd1306_clearscreen()

{

    uint8_t i = 0;

    uint8_t page = 0;

    for(page = 0; page<4; page++)

    {

        setStartPage(page);

        setStartColumn(0);

        for(i = 0; i<128; i++)

        {

            WriteData(0x00);

        }

    }

    WriteData(0x00);

}

void ssd1306_drawlogo()

{

    uint8_t i = 0;

    setStartPage(3);

    setStartColumn(0);

    for(i = 0; i<32; i++)

    {

        WriteData(row[0][i]);

    }

    WriteData(0x00);

    setStartPage(2);

    setStartColumn(0);

    for(i = 0; i<32; i++)

    {

        WriteData(row[1][i]);

    }

    WriteData(0x00);

    setStartPage(1);

    setStartColumn(0);

    for(i = 0; i<32; i++)

    {

        WriteData(row[2][i]);

    }

    WriteData(0x00);

    setStartPage(0);

    setStartColumn(0);

    for(i = 0; i<32; i++)

    {

        WriteData(row[3][i]);

    }

    WriteData(0x00);

}

/* Print a single character from font.cpp */

void ssd1306_DrawChar(char ascii, unsigned char row, unsigned char xPos)

{

    unsigned char i;

    srcPointer = &fontData[(ascii-32)][0];

    setStartPage(row);

    setStartColumn(xPos);

    for(i=0;i<5;i++)

    {

        WriteData(*srcPointer);

        srcPointer++;

    }

    WriteData(0x00);

}

void ssd1306_DrawString(const char *dataPtr, unsigned char row, unsigned char xPos)

{

    char *srcPointer;

    srcPointer = (char*)dataPtr;

    ssd1306_DrawChar(' ',row,xPos); // NBSP must be written first before the string start

    while(1)

    {

        ssd1306_DrawChar(*srcPointer,row,xPos);

        srcPointer++;

        xPos+=6;

        if(*srcPointer == 0) break;

    }

}

// vim:softtabstop=4 shiftwidth=4 expandtab 

#ifndef   ssd1306_H

#define   ssd1306_H

#define   SSD_RESET       GPIOB,GPIO_Pin_2

#define   SSD_A0          GPIOB,GPIO_Pin_10

#define   SSD_CS          GPIOB,GPIO_Pin_1

#define   SSD_Reset_Low()   GPIO_ResetBits(SSD_RESET)

#define   SSD_Reset_High()  GPIO_SetBits(SSD_RESET)

#define   SSD_A0_Low()      GPIO_ResetBits(SSD_A0)

#define   SSD_A0_High()     GPIO_SetBits(SSD_A0)

#define   SSD_CS_Low()      GPIO_ResetBits(SSD_CS)

#define   SSD_CS_High()     GPIO_SetBits(SSD_CS)

// Use stdperiph

#define   SPI_SendByte(data)  SPI_I2S_SendData(SPI1,data) 

#define   SPI_Wait()       while(!(SPI1->SR&SPI_I2S_FLAG_TXE));while(SPI1->SR&SPI_I2S_FLAG_BSY); 

void ssd1306_Init(void);

void ssd1306_DrawChar(char ascii, unsigned char row, unsigned char xPos);

void ssd1306_DrawString(const char *dataPtr, unsigned char row, unsigned char xPos);

void ssd1306_drawlogo();

void ssd1306_clearscreen();

#endif

// vim:softtabstop=4 shiftwidth=4 expandtab