#include "system/lwesp_ll.h"

#include "lwesp/lwesp.h"
#include "lwesp/lwesp_input.h"
#include "lwesp/lwesp_mem.h"
#include "stm32h7xx_hal.h"

#include "cmsis_os.h"

#define UART_TIMEOUT 1000
#define UART_BUFFER_SIZE 1024

#define HEAP_SIZE    4096

#define UART_HANDLE huart4

extern UART_HandleTypeDef UART_HANDLE;

static uint8_t s_uart_rxbuf[UART_BUFFER_SIZE];
static uint8_t            s_lwesp_heap[HEAP_SIZE];
static uint8_t            s_initialized;

static osThreadId_t usart_ll_thread_id;
static osMessageQueueId_t usart_ll_mbox_id;

void usart_rx_event_callback(UART_HandleTypeDef *huart, uint16_t Pos) {
    // Count pos in buffer, notify UART LL thread.
}

void usart_rx_cplt_callback(UART_HandleTypeDef *huart) {
    // Circular DMA is used, so no complete event will be received normally
}

void usart_error_callback(UART_HandleTypeDef *huart) {
    // Error encountered, DMA aborted.
}

static void usart_ll_thread(void *arg) {
    for (;;) {
    }
}

static void configure_uart(uint32_t baudrate) {
    // Register callbacks
    HAL_UART_RegisterCallback(&UART_HANDLE, HAL_UART_RX_COMPLETE_CB_ID, usart_rx_cplt_callback);
    HAL_UART_RegisterCallback(&UART_HANDLE, HAL_UART_ERROR_CB_ID, usart_error_callback);
    HAL_UART_RegisterRxEventCallback(&UART_HANDLE, usart_rx_event_callback);

    // Enable DMA Rx
    HAL_UART_Receive_DMA(&UART_HANDLE, s_uart_rxbuf, UART_BUFFER_SIZE);
}

static size_t send_data(const void *data, size_t len) {
    HAL_UART_Transmit(&UART_HANDLE, (uint8_t *)data, len, 1000);

    return len;
}

lwespr_t lwesp_ll_init(lwesp_ll_t *ll) {
    lwesp_mem_region_t mem_regions[] = {{s_lwesp_heap, HEAP_SIZE}};

    if (!s_initialized) {
        // Internal heap management
        lwesp_mem_assignmemory(mem_regions, LWESP_ARRAYSIZE(mem_regions));

        // Initialize callbacks
        ll->send_fn = send_data;
    }

    // Configure UART device and RX ring buffer
    configure_uart(ll->uart.baudrate);

    if(!s_initialized) {
        const osThreadAttr_t attr = {
            .stack_size = 1024
        };

        usart_ll_mbox_id = osMessageQueueNew(10, sizeof(void *), NULL);
        usart_ll_thread_id = osThreadNew(usart_ll_thread, usart_ll_mbox_id, &attr);
    }

    s_initialized = 1;

    return lwespOK;
}

lwespr_t lwesp_ll_deinit(lwesp_ll_t *ll) {
    //
    return lwespOK;
}