#include <stm32f1xx_hal.h>
#include <stm32f1xx_hal_uart.h>

#include <tuple>

#include "commons.hpp"
#include "logging.hpp"
#include "spi.hpp"

/*
 * reserve PB11-PB15 for SPI2
 */

// STM32VL-Discovery green led - PC9
#define BTN_PORT GPIOA
#define LED_PORT GPIOC
#define LED1_PIN GPIO_PIN_8
#define LED2_PIN GPIO_PIN_9
#define BTN_PIN GPIO_PIN_0
#define LED_PORT_CLK_ENABLE __HAL_RCC_GPIOC_CLK_ENABLE

#define LoRa_RESET_Pin GPIO_PIN_4
#define LoRa_RESET_GPIO_Port GPIOC
#define LoRa_CS_Pin GPIO_PIN_5
#define LoRa_CS_GPIO_Port GPIOC

#include "rfm95.hpp"

extern uint8_t LoRa_buff[RH_RF95_FIFO_SIZE];
extern SPI_HandleTypeDef hspi1;

void print_version(void) { log::info("running PentaTrack v0.1.3"); }
void print_help(void);

void loglevel_error(void) { log::set_loglevel(LogLevel::ERROR); }
void loglevel_info(void) { log::set_loglevel(LogLevel::INFO); }
void loglevel_debug(void) { log::set_loglevel(LogLevel::DEBUG); }

template <size_t Size>
class cmd_holder {
 public:
  typedef void (*functionPointerType)(void);

  using command_t =
      std::tuple<std::string_view, std::string_view, functionPointerType>;
  template <size_t S>
  using command_array_t = std::array<command_t, Size>;

  template <typename... Args>
  constexpr cmd_holder(Args... command_list)
      : commands{std::forward<Args>(command_list)...} {}

  constexpr functionPointerType get_func(std::string_view message) const {
    for (const auto &[cmd_name, cmd_help, func] : commands) {
      if (message == cmd_name) {
        return func;
      }
    }

    return nullptr;
  }

  void print_help() const {
    log::info("Listing available commands:");
    for (const auto &[cmd_name, cmd_help, func] : commands) {
      log::info("\t", cmd_name, " - ", cmd_help);
    }
  }

 private:
  std::array<command_t, Size> commands;
};

static bool updated_main_buf = false;
static buffer<uint8_t, 512> main_buffer;

void print_buf(void) { main_buffer.print(); }

class cmd_handler {
 public:
  static constexpr auto MaxCmdLength = 24;
  using array_t = std::array<uint8_t, MaxCmdLength>;
  using iterator_t = array_t::iterator;
  using const_iterator_t = array_t::const_iterator;

  constexpr cmd_handler() : symbols{}, iterator{symbols.begin()} {}

  static cmd_handler &get() {
    static auto c = cmd_handler{};
    return c;
  };

  void add_symbol(uint8_t symbol) {
    *iterator = symbol;
    iterator++;
    if (iterator == symbols.end()) {
      iterator = symbols.begin();
    }
  }

  std::string_view get_current_cmd() const {
    return {reinterpret_cast<const char *>(symbols.data()),
            static_cast<size_t>(
                std::distance(symbols.begin(), const_iterator_t{iterator}))};
  }

  bool exists() const {
    return commands.get_func(get_current_cmd()) != nullptr;
  }

  void execute() {
    const auto current_cmd = get_current_cmd();
    log::debug("Try executing command: ", current_cmd);
    const auto func = commands.get_func(current_cmd);
    iterator = symbols.begin();

    if (func == nullptr) {
      log::info("Unknown Command: ", current_cmd);
      log::info("Type 'help' to show available commands.");
      return;
    }

    func();
  }

  void queue_execution() { ShouldExecute = true; }

  void run() {
    if (ShouldExecute) {
      execute();
      ShouldExecute = false;
    }
  }

  void print_help_() const { commands.print_help(); }

 private:
  static constexpr cmd_holder<6> commands{
      std::make_tuple("ver", "Prints current version.", &print_version),
      std::make_tuple("error", "Set LogLevel to Error.", &loglevel_error),
      std::make_tuple("info", "Set LogLevel to Info.", &loglevel_info),
      std::make_tuple("debug", "Set LogLevel to Debug.", &loglevel_debug),
      std::make_tuple("buf", "Prints gps uart buffer", &print_buf),
      std::make_tuple("help", "Prints available commands", &print_help)};

  array_t symbols;
  iterator_t iterator;
  bool ShouldExecute = false;
};

void print_help(void) { cmd_handler::get().print_help_(); }

// This prevent name mangling for functions used in C/assembly files.
extern "C" {
void SysTick_Handler(void) {
  HAL_IncTick();
  HAL_SYSTICK_IRQHandler();
}

void USART2_IRQHandler(void) {
  HAL_UART_IRQHandler(&gps_interface::s_UARTHandle);
  HAL_UART_Receive_IT(&gps_interface::s_UARTHandle, uart_interface::get_buf(),
                      1);
}

void USART1_IRQHandler(void) {
  HAL_UART_IRQHandler(&uart_interface::s_UARTHandle);
  HAL_UART_Receive_IT(&uart_interface::s_UARTHandle, uart_interface::get_buf(),
                      1);
}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) {
  if (huart == &gps_interface::s_UARTHandle) {
    return;
  }

  const uint8_t value = *uart_interface::get_buf();

  if (value == '\r') {
    cmd_handler::get().queue_execution();
    HAL_GPIO_TogglePin(LED_PORT, LED2_PIN);
    return;
  }

  cmd_handler::get().add_symbol(value);
}

void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart) {
  // const uint8_t value = *gps_interface::get_buf();
  // gps_interface::write({reinterpret_cast<const char *>(&value), 1});
}

void HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size) {
  // log::debug("DMA Callback");

  HAL_GPIO_WritePin(LED_PORT, LED1_PIN, GPIO_PIN_SET);
  if (main_buffer.copy_from(gps_interface::new_rx_buf, Size)) {
    log::debug("Copied to main buff");
    updated_main_buf = true;
  }
  HAL_GPIO_WritePin(LED_PORT, LED1_PIN, GPIO_PIN_RESET);

  HAL_UARTEx_ReceiveToIdle_DMA(&gps_interface::s_UARTHandle,
                               gps_interface::new_rx_buf.data(),
                               gps_interface::new_rx_buf.size());
  __HAL_DMA_DISABLE_IT(&gps_interface::s_DMAHandle, DMA_IT_HT);
}

/**
 * @brief This function handles DMA1 channel6 global interrupt.
 */
void DMA1_Channel6_IRQHandler(void) {
  /* USER CODE BEGIN DMA1_Channel6_IRQn 0 */

  /* USER CODE END DMA1_Channel6_IRQn 0 */
  HAL_DMA_IRQHandler(&gps_interface::s_DMAHandle);

  /* USER CODE BEGIN DMA1_Channel6_IRQn 1 */

  /* USER CODE END DMA1_Channel6_IRQn 1 */
}
}

void initGPIO() {
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();

  GPIO_InitTypeDef GPIO_Config2;
  GPIO_Config2.Mode = GPIO_MODE_INPUT;
  GPIO_Config2.Pull = GPIO_PULLDOWN;
  GPIO_Config2.Speed = GPIO_SPEED_FREQ_HIGH;
  GPIO_Config2.Pin = BTN_PIN;

  GPIO_InitTypeDef GPIO_Config;
  GPIO_Config.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_Config.Pull = GPIO_NOPULL;
  GPIO_Config.Speed = GPIO_SPEED_FREQ_HIGH;
  GPIO_Config.Pin = LED1_PIN | LED2_PIN;

  GPIO_InitTypeDef GPIO_ConfigSPI;
  GPIO_ConfigSPI.Mode = GPIO_MODE_OUTPUT_PP;
  // GPIO_ConfigSPI.Pull = GPIO_NOPULL;
  GPIO_ConfigSPI.Speed = GPIO_SPEED_FREQ_HIGH;
  GPIO_ConfigSPI.Pin = LoRa_CS_Pin | LoRa_RESET_Pin;

  // bare metal init of led1:
  // volatile uint32_t* CRH = reinterpret_cast<uint32_t*>(0x40011000 +
  // 0x04);
  //*CRH |= 0x3;
  //*CRH &= (~0xC);

  HAL_GPIO_Init(LED_PORT, &GPIO_Config);
  HAL_GPIO_Init(BTN_PORT, &GPIO_Config2);
  HAL_GPIO_Init(LoRa_CS_GPIO_Port, &GPIO_ConfigSPI);
  //  HAL_GPIO_WritePin(LoRa_CS_GPIO_Port, LoRa_CS_Pin, GPIO_PIN_SET);
  //  HAL_GPIO_WritePin(LoRa_RESET_GPIO_Port, LoRa_RESET_Pin,
  //  GPIO_PIN_SET);
}

extern "C" {
#include <stdio.h>

void start_interrupt() {
  HAL_UARTEx_ReceiveToIdle_DMA(&gps_interface::s_UARTHandle,
                               gps_interface::new_rx_buf.data(),
                               gps_interface::new_rx_buf.size());
  __HAL_DMA_DISABLE_IT(&gps_interface::s_DMAHandle, DMA_IT_HT);
}
}

int main(void) {
  HAL_Init();
  HAL_SYSTICK_Config(1);
  initGPIO();

  if (!log::init<uart_logger>()) {
    // toggle status led or something
  }
  log::set_loglevel(LogLevel::DEBUG);
  log::info("logging Initialized");

  if (!MX_SPI1_Init()) {
    // toggle status led or something
  }

  if (!gps_interface::init()) {
    log::error("UART2 Initialization failed, needed for GPS");
  } else {
    log::debug("Uart2 Initialized");
  }

  HAL_GPIO_WritePin(LoRa_CS_GPIO_Port, LoRa_CS_Pin, GPIO_PIN_SET);
  HAL_GPIO_WritePin(LoRa_RESET_GPIO_Port, LoRa_RESET_Pin, GPIO_PIN_SET);
  HAL_Delay(1000);

  log::debug("SPI1 Initialized.");
  log::debug("Initialization done.");

  char OP_Mode = 0x01;
  char buff = 0x7F & OP_Mode;
  char res = 0;

  HAL_GPIO_WritePin(LoRa_CS_GPIO_Port, LoRa_CS_Pin, GPIO_PIN_RESET);
  [[maybe_unused]] auto result =
      HAL_SPI_Transmit(&hspi1, (uint8_t *)&buff, 1, 100);
  HAL_SPI_Receive(&hspi1, (uint8_t *)&res, 1, 100);
  HAL_GPIO_WritePin(LoRa_CS_GPIO_Port, LoRa_CS_Pin, GPIO_PIN_SET);

  // RF95_Init();

  while (1) {
    cmd_handler::get().run();

    // gps_interface::write("TEST");
    //  RF95_setModeRx_Continuous();
    // HAL_GPIO_WritePin(LED_PORT, LED1_PIN, GPIO_PIN_RESET);
    // RF95_receive(LoRa_buff);
    // HAL_Delay(100);
    // HAL_GPIO_WritePin(LED_PORT, LED1_PIN, GPIO_PIN_SET);
    HAL_Delay(100);

    // if (updated_main_buf) {
    //   log::debug("Printing main buf");
    //   updated_main_buf = !main_buffer.print();
    // }

    // std::string_view msg{reinterpret_cast<char *>(LoRa_buff)};
    // log::info("Received Message");
    // log::debug("Received Message");
    // log::debug(msg);

    // std::string_view foo{"Das ist ein test"};
    // strcpy((char *)LoRa_buff, foo.data());

    // RF95_send(LoRa_buff);
  }

  return 0;
}