#include "mbed.h"
#include "main.h"
#include "SWO.h"
#include "pca9685.h"
#include "tusb322.h"
#include "ds3231.h"
#include "ioc.h"
#include "animation.h"

I2C i2c(PA_10, PA_9);
// SWO_Channel swo("swo");

bool RtcTick, RefreshTick, RngTick;
bool StartupFlag, RuntimeFlag;

typedef struct {
    char PrevDigit;     // Previous digit to fade out
    ushort PrevValue;   // Brightness of previous digit
    char NextDigit;     // Next digit to fade in
    ushort NextValue;   // Brightness of next digit
    bool RefreshActive;
} Digit;

Digit Digits[NUM_DIGITS] = {0};  // Active per-tube digit setting

int DotNextValue, DotPrevValue;
bool DotIncrement = false;

Ticker StartupUpdateTicker, RuntimeUpdateTicker, RngUpdateTicker;
int StartupTickerIter, RuntimeTickerIter, RngTickerIter;

void RtcTickCallback(void) {
    RtcTick = true;
}

void RefreshTickCallback(void) {
    RefreshTick = true;
}

void RngTickCallback(void) {
    RngTick = true;
}

void StartupTickerUpdate(void) {

    for (int i = 0; i < NUM_DIGITS; i++) {
        if (!Digits[i].RefreshActive) {
            Digits[i].NextValue = (i == 0 && Digits[i].NextDigit == 0) ? 0 : Digits[i].NextValue + FADE_TICK_STEP;
        }
    }

    DotNextValue += FADE_TICK_STEP;

    if (--StartupTickerIter == 0) {
        StartupUpdateTicker.detach();
        for (int i = 0; i < NUM_DIGITS; i++) {
            Digits[i].PrevDigit = Digits[i].NextDigit;
        }

        // Switch to runtime mode once startup sequence has completed
        RuntimeFlag = true;
    }
}

void RuntimeTickerUpdate(void) {

    for (int i = 0; i < NUM_DIGITS; i++) {
        if(!Digits[i].RefreshActive && Digits[i].PrevDigit != Digits[i].NextDigit) {
            Digits[i].PrevValue -= FADE_TICK_STEP;
            Digits[i].NextValue = (i == 0 && Digits[i].NextDigit == 0) ? 0 : Digits[i].NextValue + FADE_TICK_STEP;
        }
    }

    DotNextValue = DotIncrement ? DotNextValue + FADE_TICK_STEP: DotNextValue - FADE_TICK_STEP;

    if (--RuntimeTickerIter == 0) {
        RuntimeUpdateTicker.detach();
        for (int i = 0; i < NUM_DIGITS; i++) {
            Digits[i].PrevDigit = Digits[i].NextDigit;
        }
        DotIncrement = !DotIncrement;
    }
}

void RngTickerUpdate(void) {


    if (--RngTickerIter == 0) {
        RngUpdateTicker.detach();
    }
}

int main() {
    
    RtcTick = false;
    RefreshTick = false;
    RngTick = false;
    StartupFlag = true;
    RuntimeFlag = false;

    // Start I2C at 400kHz for DS3231 
    i2c.frequency(400000);
    
    // Start with HV PSU disabled
    HV_EnableOutput(false);
    
    TUSB322_Init();
    PCA9685_Init();
    DS3231_Init(RtcTickCallback);
    
    // Enable HV PSU
    HV_EnableOutput(true);
    
    // Set PCA9685 input voltage to highest possible
    PCA9685_SetVoltage(1.0);
    
    // swo.printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);
    
    // Bump I2C frequency to 1MHz
    i2c.frequency(1000000);

    // Setup a ticker to refresh the display at 1kHz
    Ticker refreshTicker;
    refreshTicker.attach_us(RefreshTickCallback, DIGIT_REFRESH_RATE_US);

    // Kick off the RNG ticker at 0.1Hz
    Ticker rngTicker;
    rngTicker.attach(RngTickCallback, DIGIT_RNG_REFRESH_RATE_S);

    // DS3231_SetTime(0, 55, 6, true);
    // DS3231_SetDate(0, 2, 12, 18, 0);

    while(1) {

        // Animate_Cycle_Basic();
        // Animate_Cycle_Analog();
        // Animate_Cycle_Low_Pwm();
        // Animate_Cycle_Pwm();
        // Animate_Cycle_Fade();
        // Animate_Cycle_Fade_Random();
        // Animate_Cycle_Fast();
        // Animate_Cycle_Fast_Random();

        if (RefreshTick) {

            RefreshTick = false;

            // On refresh, update the display with new values

            // If brightness has changed, update both prevous and next digits with new values
            for (int i = 0; i < NUM_DIGITS; i++) {
                if (Digits[i].NextValue != Digits[i].PrevValue) {
                    PCA9685_SetDigit(i, Digits[i].PrevDigit, Digits[i].PrevValue);
                    PCA9685_SetDigit(i, Digits[i].NextDigit, Digits[i].NextValue);
                }
            }

            if (DotNextValue != DotPrevValue) {
                PCA9685_SetDot(DotNextValue);
            }

            // Update previous values to what was just set

            for (int i = 0; i < NUM_DIGITS; i++) {
                Digits[i].PrevValue = Digits[i].NextValue;
            }
            DotPrevValue = DotNextValue;
        }

        if (RtcTick) {
            
            RtcTick = false;

            // On RTC 1Hz ticks, get the time and begin update

            int nextSecond, nextMinute, nextHour;
            DS3231_GetTime(&nextSecond, &nextMinute, &nextHour);

            Digits[3].NextDigit = nextMinute % 10;
            Digits[2].NextDigit = nextMinute / 10;
            Digits[1].NextDigit = nextHour % 10;
            Digits[0].NextDigit = nextHour / 10;

            if (StartupFlag) {

                // Fade in the current time
                StartupTickerIter = FADE_TICKS;
                StartupUpdateTicker.attach(StartupTickerUpdate, (DIGIT_REFRESH_RATE_US/1000)/StartupTickerIter);
                StartupFlag = false;
            } 

            if (RuntimeFlag) {

                // Fade in the new time
                RuntimeTickerIter = FADE_TICKS;
                RuntimeUpdateTicker.attach(RuntimeTickerUpdate, (DIGIT_REFRESH_RATE_US/1000)/RuntimeTickerIter);
            }
        }

        if (RngTick) {

            // Choose a random tube to refresh
            Digits[rand() % 4].RefreshActive = true;

            RngTickerIter = DIGIT_RNG_REFRESH_ITER * FADE_TICKS;
            RngUpdateTicker.attach(RngTickerUpdate, (DIGIT_REFRESH_RATE_US/1000)/FADE_TICKS);
            RngTick = false;
        }
    }
}

void I2C_Write(int DeviceAddress, char RegAddress, char *Data, int Length) {
    char buffer[I2C_MAX_BUFFER+1] = {0};

    if (Length > I2C_MAX_BUFFER) LED_Fault(1);

    buffer[0] = RegAddress;
    memcpy(&buffer[1], Data, Length);

    i2c.write(DeviceAddress << 1, buffer, Length + 1);
}

void I2C_Read(int DeviceAddress, char RegAddress, char *Data, int Length) {
    
    i2c.write(DeviceAddress << 1, &RegAddress, 1);
    i2c.read(DeviceAddress << 1, Data, Length);
}