//
// Created by YangYongbao on 2017/3/18.
//

#include "uart_log.h"
#include "stm32f10x.h"
#include "stm32f10x_conf.h"

void uart_log_init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;

    RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd( RCC_APB1Periph_USART2, ENABLE);

    /* USART2 GPIO config */
    /* Configure USART2 Tx (PA2) as alternate function push-pull */
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    /* Configure USART2 Rx (PA3) as input floating */
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    /* USART2 mode config */
    USART_InitStructure.USART_BaudRate = 115200;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_Parity = USART_Parity_No ;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USART2, &USART_InitStructure);
    USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);

    USART_Cmd(USART2, ENABLE);
}
void uart_putchar(unsigned int c)
{
    while (USART_GetFlagStatus(USART2, USART_FLAG_TXE) == RESET);
    USART_SendData(USART2, (uint16_t)c);   
}

int uart_getchar(void)
{
    return 0;
}

static void printchar(char **str, unsigned int c)
{
    while (USART_GetFlagStatus(USART2, USART_FLAG_TXE) == RESET);
    USART_SendData(USART2, (uint16_t)c);
}

#ifdef USE_CUSTOM_PRINTF
#define PAD_RIGHT 1
#define PAD_ZERO 2

static int prints(char **out, const char *string, int width, int pad)
{
    register int pc = 0, padchar = ' ';

    if (width > 0) {
        register int len = 0;
        register const char *ptr;
        for (ptr = string; *ptr; ++ptr) ++len;
        if (len >= width) width = 0;
        else width -= len;
        if (pad & PAD_ZERO) padchar = '0';
    }
    if (!(pad & PAD_RIGHT)) {
        for ( ; width > 0; --width) {
            printchar (out, padchar);
            ++pc;
        }
    }
    for ( ; *string ; ++string) {
        printchar (out, *string);
        ++pc;
    }
    for ( ; width > 0; --width) {
        printchar (out, padchar);
        ++pc;
    }

    return pc;
}

/* the following should be enough for 32 bit int */
#define PRINT_BUF_LEN 12

static int printi(char **out, int i, int b, int sg, int width, int pad, int letbase)
{
    char print_buf[PRINT_BUF_LEN];
    register char *s;
    register int t, neg = 0, pc = 0;
    register unsigned int u = i;

    if (i == 0) {
        print_buf[0] = '0';
        print_buf[1] = '\0';
        return prints (out, print_buf, width, pad);
    }

    if (sg && b == 10 && i < 0) {
        neg = 1;
        u = -i;
    }

    s = print_buf + PRINT_BUF_LEN-1;
    *s = '\0';

    while (u) {
        t = u % b;
        if( t >= 10 )
            t += letbase - '0' - 10;
        *--s = t + '0';
        u /= b;
    }

    if (neg) {
        if( width && (pad & PAD_ZERO) ) {
            printchar (out, '-');
            ++pc;
            --width;
        }
        else {
            *--s = '-';
        }
    }

    return pc + prints (out, s, width, pad);
}

static int print( char **out, const char *format, va_list args )
{
    register int width, pad;
    register int pc = 0;
    char scr[2];

    for (; *format != 0; ++format) {
        if (*format == '%') {
            ++format;
            width = pad = 0;
            if (*format == '\0') break;
            if (*format == '%') goto out;
            if (*format == '-') {
                ++format;
                pad = PAD_RIGHT;
            }
            while (*format == '0') {
                ++format;
                pad |= PAD_ZERO;
            }
            for ( ; *format >= '0' && *format <= '9'; ++format) {
                width *= 10;
                width += *format - '0';
            }
            if( *format == 's' ) {
                register char *s = (char *)va_arg( args, int );
                pc += prints (out, s?s:"(null)", width, pad);
                continue;
            }
            if( *format == 'd' ) {
                pc += printi (out, va_arg( args, int ), 10, 1, width, pad, 'a');
                continue;
            }
            if( *format == 'x' ) {
                pc += printi (out, va_arg( args, int ), 16, 0, width, pad, 'a');
                continue;
            }
            if( *format == 'X' ) {
                pc += printi (out, va_arg( args, int ), 16, 0, width, pad, 'A');
                continue;
            }
            if( *format == 'u' ) {
                pc += printi (out, va_arg( args, int ), 10, 0, width, pad, 'a');
                continue;
            }
            if( *format == 'c' ) {
                /* char are converted to int then pushed on the stack */
                scr[0] = (char)va_arg( args, int );
                scr[1] = '\0';
                pc += prints (out, scr, width, pad);
                continue;
            }
        }
        else {
            out:
            printchar (out, *format);
            ++pc;
        }
    }
    if (out) **out = '\0';
    va_end( args );
    return pc;
}

int printf(const char *format, ...)
{
    va_list args;

    va_start( args, format );
    return print( 0, format, args );
}

void debug(const char *format, ...)
{
    va_list args;

    va_start( args, format );
    print( 0, format, args );
    print(0, "\n", args);
}

int sprintf(char *out, const char *format, ...)
{
    va_list args;

    va_start( args, format );
    return print( &out, format, args );
}

int snprintf( char *buf, unsigned int count, const char *format, ... )
{
    va_list args;

    ( void ) count;

    va_start( args, format );
    return print( &buf, format, args );
}
#endif

// UART2 interrupt
void USART2_IRQHandler(void)
{
    uint8_t data;
    if (USART_GetITStatus(USART2, USART_IT_RXNE) != RESET)
    {
        data = USART_ReceiveData(USART2);
        // add usart receive here
        // uart_receive_input(data);

        USART_ClearFlag(USART2, USART_FLAG_RXNE);
        USART_ClearITPendingBit(USART2, USART_IT_RXNE);
    }
}