/*
Main Source File
*/
#include "adc.h"
#include "battery.h"
#include "cc_cv_charging.h"
#include "dac.h"
#include "i2c_target.h"
#include "multiplexer.h"
#include "ti/comm_modules/i2c/controller/i2c_comm_controller.h"
#include "ti/devices/msp/peripherals/hw_dac12.h"
#include "ti/driverlib/dl_adc12.h"
#include "ti/driverlib/dl_gpio.h"
#include "ti/driverlib/dl_i2c.h"
#include "ti/driverlib/m0p/dl_core.h"
#include "ti_msp_dl_config.h"
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <ti/drivers/GPIO.h>

I2C_Instance gI2C;
I2C_ResponseInfo gResponse;
BatteryData battery_data;

/*Interrupt for MCU -> ADC
* CASE: DL_I2C_IIDX_CONTROLLER_RX_DONE: ADC Reception Complete
    - ADC has finished sending data and it's fully received.
    - gI2C.rxMsg.len = gI2C.rxMsg.ptr:
        - Stores the received data length in the response buffer.
    - I2C_decodeResponse():
        - Decodes the received response.
    - gI2C.status = I2C_STATUS_RX_COMPLETE:
        - Marks reception is complete.
* CASE: DL_I2C_IIDX_CONTROLLER_TX_DONE: Data Transmit to ADC complete
    - DL_I2C_disableInterrupt(..): Disables the TXFIFO interrupt since data is
now sent
* CASE: DL_I2C_IIDX_CONTROLLER_RXFIFO_TRIGGER: Receive Data in FIFO
    - The I2C Receive FIFO has data ready to be read.
    - while (DL_I2C_isControllerRXFIFOEmpty(...) != true): Loops until the RX
FIFOis empty (READ all available bytes)
    - Inside the while loop:
        - If buffer has SPACE, store the received byte
        - Prints each received byte in HEXADECIMAL format for debugging
        - IF BUFFER is FULL, avoids OVERFLOW by discarding extra byte.
* CASE: DL_I2C_IIDX_CONTROLLER_TXFIFO_TRIGGER: Transmit Data in FIFO
        - If there is still data to send:
        gI2C.txMsg.ptr += DL_I2C_fillControllerTXFIFO(I2C_controller_INST,
&gI2C.txMsg.buffer[gI2C.txMsg.ptr], gI2C.txMsg.len - gI2C.txMsg.ptr);

*/
void I2C_controller_INST_IRQHandler(void) {
  // printf("I2C Interrupt Triggered to ADC!\n");
  switch (DL_I2C_getPendingInterrupt(I2C_controller_INST)) { /*START Condition*/
  case DL_I2C_IIDX_CONTROLLER_START:
    // gTxADCcount= 0;
    gRxADCcount = 0;
    DL_I2C_flushControllerTXFIFO(I2C_controller_INST);
    break;

  case DL_I2C_IIDX_CONTROLLER_RXFIFO_TRIGGER:
    gI2C.status = I2C_STATUS_RX_INPROGRESS;
    /* Store bytes received from target in Rx Msg Buffer */
    while (DL_I2C_isControllerRXFIFOEmpty(I2C_controller_INST) != true) {
      if (gRxADCcount < gRxADClen) {
        gRxPacket[gRxADCcount] =
            DL_I2C_receiveControllerData(I2C_controller_INST);
        printf("Received Byte[%d]: 0x%02X\n", gRxADCcount,
               gRxPacket[gRxADCcount]); // Debug print
        gRxADCcount++;

      } else {
        // printf("ERROR: RX Buffer Overflow! ptr=%d MAX_BUFFER_SIZE=%d\n",
        // gI2C.rxMsg.ptr, MAX_BUFFER_SIZE);
        /* Ignore and remove from FIFO if the buffer is full */
        DL_I2C_receiveControllerData(I2C_controller_INST);
      }
    }
    if (gRxADCcount >= gRxADClen) {
      // printf("ADC Bytes Received!\n");
      gRxComplete = true;
      DL_I2C_enableInterrupt(I2C_controller_INST,
                             DL_I2C_INTERRUPT_CONTROLLER_STOP);
    }
    break;
  /*TRANSMIT data to ADC*/
  case DL_I2C_IIDX_CONTROLLER_TXFIFO_TRIGGER:
    // printf("TX FIFO with data!\n");
    gI2C.status = I2C_STATUS_TX_INPROGRESS;
    if (gTxADCcount < gTxADClen) {
      gTxADCcount += DL_I2C_fillControllerTXFIFO(I2C_controller_INST,
                                                 &gTxPacket[gTxADCcount],
                                                 (gTxADClen - gTxADCcount));
    } else {
      /*Prevent overflow and just ignore data*/
      DL_I2C_fillTargetTXFIFO(I2C_controller_INST, (uint8_t[]){0x00}, 1);
      gTxComplete = true;
    }
    // DL_I2C_flushControllerTXFIFO(I2C_controller_INST);
    break;
  /*STOP condition*/
  case DL_I2C_IIDX_CONTROLLER_STOP:
    gTxComplete = true;
    gRxComplete = true;
    // printf("I2C Stop Detected- RX Complete");
    break;
  case DL_I2C_IIDX_CONTROLLER_ARBITRATION_LOST:
    // printf("Interrupt index for I2C controller Arbitration Lost!\n");
    break;
  case DL_I2C_IIDX_CONTROLLER_NACK:
    // printf("I2C NACK Received\n");
    if ((gI2C.status == I2C_STATUS_RX_STARTED) ||
        (gI2C.status = I2C_STATUS_TX_STARTED)) {
      gI2C.status = I2C_STATUS_ERROR;
    }
    break;
  default:
    break;
  }
}

/**** Interrupt for Pi to MCU ****/
void I2C_target_INST_IRQHandler(void) {
  uint8_t receivedCommand = 0;
  uint8_t battery_state[8] = {0x00};
  uint32_t status = DL_I2C_getPendingInterrupt(I2C_target_INST);
  printf("status: %d\n", status);
  switch (status) {
  case DL_I2C_IIDX_TARGET_START:
    /*Initialize Tx or RX after Start condition is recieved*/
    piTxCount = 0;
    piRxCount = 0;
    piTxComplete = false;
    DL_I2C_flushTargetTXFIFO(I2C_target_INST);
    break;
  case DL_I2C_IIDX_TARGET_STOP:
    piTxComplete = true;
    piRxComplete = true;
    DL_I2C_flushTargetTXFIFO(I2C_target_INST);
    DL_I2C_flushTargetRXFIFO(I2C_target_INST);
    break;
  case DL_I2C_IIDX_TARGET_RXFIFO_TRIGGER:
    printf("Rx Interrupt Triggered \n");
    if (DL_I2C_isTargetRXFIFOEmpty(I2C_target_INST)) {
      return;
    }
    receivedCommand = DL_I2C_receiveTargetData(I2C_target_INST);
    if (receivedCommand == CMD_GET_BATTERY_STATUS) {
      printf("Received Command: 0x%02X\n", receivedCommand);
      for (uint8_t slot = 0; slot < NUM_SLOTS; slot++) {
        battery_state[slot] = batteries[slot].state;
      }

      DL_I2C_fillTargetTXFIFO(I2C_target_INST, battery_state, 8);
      while (DL_I2C_transmitTargetDataCheck(I2C_target_INST, 0x00) != false)
        ;
      printf("Sent Data\n");
    }

    /*
    To receive the Battery Mesaurements from MCU, bit masking is applied
    where:
    - command type is upper 4 bits: 0010 (for CMD_GET_BATTERY_DATA)->
    consistent
    - slot_id is lower 3 bits, since NUM_SLOTS are 8 so it ranges from 000
    till 111
    - bit mask for command is 0xF0: 11110000
    - bit mask for requested slot is 0x07: 00000111
    receivedCommand now ranges from 0x20 till 0x27
    */

    else if ((receivedCommand & 0xF0) == 0x20) {

      //printf("Received Command: 0x%02X\n", receivedCommand);
      uint8_t requestedSlot = (receivedCommand & 0x07);
      //printf("Requested slot:%d\n", requestedSlot);
      // piTxCount = 0;
      piTxLen = sizeof(BatteryData);
      BatteryData battery_data;

      if (requestedSlot >= NUM_SLOTS) {
        //printf("Requested Slot is not valid.\n");
        DL_I2C_flushTargetTXFIFO(I2C_target_INST);
        return;
      }

      Battery *battery = &batteries[requestedSlot];
      battery_data.slot_id = battery->slot_id; // !TODO: recheck if necessary
      //printf("slot_id:%u\n", battery_data.slot_id);
      battery_data.voltage = battery->voltage;
      //printf("voltage:%u\n", battery_data.voltage);
      battery_data.current = battery->current;
      //printf("current:%u\n", battery_data.current);
      battery_data.temperature = battery->temperature;
      //printf("temperature:%u\n", battery_data.temperature);
      DL_I2C_fillTargetTXFIFO(I2C_target_INST, (uint8_t *)&battery_data,
                              piTxLen);

      /*piTxComplete= true;
      if(piTxCount >= piTxLen){
          piTxComplete= true;
          piTxCount= 0;
      }*/
      printf("Battery Measurement Sent. \n");
      DL_I2C_flushTargetTXFIFO(I2C_target_INST);

    }

    else if (receivedCommand == CMD_SET_BATTERY_LIMIT) {
      uint8_t rx_buffer[sizeof(BatteryLimitMsg)];
      uint8_t index = 0;

      while (!DL_I2C_isTargetRXFIFOEmpty(I2C_target_INST)) {
        if (index < sizeof(BatteryLimitMsg)) {
          rx_buffer[index] = DL_I2C_receiveTargetData(I2C_target_INST);
          index++;
        } else {
          DL_I2C_receiveTargetData(I2C_target_INST);
        }
      }

      if (index == sizeof(BatteryLimitMsg)) {
        BatteryLimitMsg battery_limits;
        memcpy(&battery_limits, rx_buffer, sizeof(BatteryLimitMsg));
        if (battery_limits.slot_id < NUM_SLOTS) {
          Battery *battery = &batteries[battery_limits.slot_id];
          battery->min_voltage = battery_limits.min_voltage;
          battery->max_voltage = battery_limits.max_voltage;
          battery->cut_off_current = battery_limits.cut_off_current;
          battery->capacitance = battery_limits.capacitance;
          battery->charge_fraction = battery_limits.charge_fraction;
        }
      }
    }

    break;
  case DL_I2C_IIDX_TARGET_TXFIFO_TRIGGER:
    break;
  case DL_I2C_IIDX_TARGET_ARBITRATION_LOST:
    break;
  default:
    break;
  }
}

/********MAIN function*************/

int main(void) {
  // Initialize System and I2C
  SYSCFG_DL_init();

  // Initialize battery array and default params
  Battery_Init();

  // Reset_I2C_Bus();
  NVIC_EnableIRQ(I2C_target_INST_INT_IRQN);
  NVIC_EnableIRQ(I2C_controller_INST_INT_IRQN);

  printf("............System Configuration Enabled...............\n");

  // Multiplexer
  Multiplexer_SelectChannel(I2C_CHANNEL);
  // I2C_scanBus();
  I2C_init(&gI2C);

  // ADC_SetConfigurationBytes(adc_voltage_params);
  // delay_cycles(50000);
  // ADC_SetConfigurationBytes(adc_current_params);
  // delay_cycles(50000);
  // DAC_ReadCurrentAddress();

  while (1) {
    // Looping through the ADC Channels
    for (uint8_t slot_id = 0; slot_id < NUM_SLOTS; slot_id++) {
      for (uint8_t adc_channel = 0; adc_channel < ADC_CHANNEL_NUM;
           adc_channel++) {
        Battery_UpdateADCReading(slot_id, adc_channel);
      }
      Battery_ReadState(slot_id);
    }
    printf("Battery Details: Slot: %u, Voltage:%u, Current: %u \n, State:%u\n:",
           batteries[0].slot_id, batteries[0].voltage, batteries[0].current,
           batteries[0].state);

    // CC-CV Cycle: maximum cycles is not yet implemented
    // for(uint8_t slot_id= 0; slot_id < NUM_SLOTS; slot_id++){
    //     CC_CV_ControlCharging(slot_id);
    // }

    // DAC_fastWrite(CHANNEL_A_VALUE);
  }
}