#include "BSP_SDLogger.h"
#include "fatfs.h"
#include "ulog.h"
#include "stdio.h"
#include "string.h"

uint8_t block_buffer[512] = {0};
size_t block_buffer_index = 0;
char file_name[20];

char ulog_buffer[ULOG_MAX_MESSAGE_LENGTH] = {0};

void BSP_SDLogger_ULOG(ulog_level_t level, char *msg) {
    uint32_t send_length =  snprintf(ulog_buffer, ULOG_MAX_MESSAGE_LENGTH, "[%s] %s\n", ulog_level_name(level), msg);
    BSP_SDLogger_Write(ulog_buffer, send_length);
}

#include "cmsis_os2.h"

// Define the mutex
osMutexId_t logger_mutex;

// init the logger buffer and the file
// filename is generated based on the log number
void BSP_SDLogger_Init(int log_number) {

    // create the file name
    sprintf(file_name, "log_%d.txt", log_number);

    // open the file
    FIL file;
    FRESULT res = f_open(&file, file_name, FA_CREATE_ALWAYS | FA_WRITE);
    if (res != FR_OK) {
        ULOG_ERROR("Failed to open file %s", file_name);
    }

    ULOG_SUBSCRIBE(BSP_SDLogger_ULOG, ULOG_DEBUG_LEVEL);

    // close the file
    f_close(&file);

    // Create the mutex
    logger_mutex = osMutexNew(NULL);
}

// this fuctions assumes you have the mutex
void BSP_SDLogger_Flush_private() {
    // open the file
    FIL file;
    FRESULT res = f_open(&file, file_name, FA_OPEN_APPEND | FA_WRITE );
    if (res != FR_OK) {
        ULOG_ERROR("Failed to open file %s", file_name);
    }

    // write the buffer to the file
    UINT bytes_written;
    res = f_write(&file, block_buffer, block_buffer_index, &bytes_written);
    if (res != FR_OK) {
        ULOG_ERROR("Failed to write to file %s", file_name);
    }

    // close the file
    f_close(&file);

    // reset the buffer index
    block_buffer_index = 0;

}


void BSP_SDLogger_Flush() {
    // Acquire the mutex
    osMutexAcquire(logger_mutex, osWaitForever);

    // flush the buffer
    BSP_SDLogger_Flush_private();

    // Release the mutex
    osMutexRelease(logger_mutex);
}

// write data to the logger
// data is only written to the buffer!
// once the buffer is full, the data is written to the file
void  BSP_SDLogger_Write(char *data, size_t length) {
    // Acquire the mutex
    osMutexAcquire(logger_mutex, osWaitForever);

    size_t buffer_size = sizeof(block_buffer);
    size_t remaining_size = buffer_size - block_buffer_index;

    // if the data is larger than the remaining space in the buffer
    if (length > remaining_size) {
        // write the remaining space to the buffer
        memcpy(&block_buffer[block_buffer_index], data, remaining_size);
        block_buffer_index += remaining_size;
        // write the buffer to the file
        BSP_SDLogger_Flush_private();
        // write the remaining data to the buffer
        memcpy(&block_buffer[block_buffer_index], &data[remaining_size], length - remaining_size);
        block_buffer_index = length - remaining_size;
    } else {
        // write the data to the buffer
        memcpy(&block_buffer[block_buffer_index], data, length);
        block_buffer_index += length;
    }

    // Release the mutex
    osMutexRelease(logger_mutex);
}