#include <stdio.h>
#include "stm32f10x_gpio.h"
#include "stm32f10x_rcc.h"
#include "i2c.h"
#include "debug.h"


static void I2C1_InitI2C(void);
static void I2C2_InitI2C(void);
static int8_t I2C1_Timeout(I2C_TypeDef* I2Cx, int8_t val);

//static char IsInitialized = 0;


void I2C1_Init(I2C_TypeDef* I2Cx) {
	GPIO_InitTypeDef  GPIO_InitStructure;

	// initialize only once!
	/*if(IsInitialized) {
		return;
	}*/

	if(I2C1 == I2Cx) {
		// I2C-Clock enable
		RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);

		// Clock Enable Pins
		RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE);

		// I2C reset
		RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, ENABLE);
		RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, DISABLE);

		GPIO_PinRemapConfig(GPIO_Remap_I2C1, ENABLE);

		GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
		GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

		// SCL-Pin
		GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
		GPIO_Init(GPIOB, &GPIO_InitStructure);

		// I2C init
		I2C1_InitI2C();

	} else if(I2C2 == I2Cx) {
		// I2C-Clock enable
		RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);

		// Clock Enable Pins
		RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);

		// I2C reset
		RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C2, ENABLE);
		RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C2, DISABLE);


		GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
		GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

		// SCL-Pin
		GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
		GPIO_Init(GPIOB, &GPIO_InitStructure);

		// I2C init
		I2C2_InitI2C();
	}

	//IsInitialized = 1;
}

static void I2C1_InitI2C(void)
{
    I2C_InitTypeDef  I2C_InitStructure;

    I2C_DeInit(I2C1);

    // I2C-Config
    I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
    I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
    I2C_InitStructure.I2C_OwnAddress1 = 0;
    I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
    I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
    I2C_InitStructure.I2C_ClockSpeed = I2C1_CLOCK_FRQ;

    // Init Struktur
    I2C_Init(I2C1, &I2C_InitStructure);

    // I2C enable
    I2C_Cmd(I2C1, ENABLE);
}

static void I2C2_InitI2C(void)
{
    I2C_InitTypeDef  I2C_InitStructure;

    I2C_DeInit(I2C2);

    // I2C-Config
    I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
    I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
    I2C_InitStructure.I2C_OwnAddress1 = 0;
    I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
    I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
    I2C_InitStructure.I2C_ClockSpeed = I2C1_CLOCK_FRQ;

    // Init Struktur
    I2C_Init(I2C2, &I2C_InitStructure);

    // I2C enable
    I2C_Cmd(I2C2, ENABLE);
}

int16_t I2C1_ReadByte(I2C_TypeDef* I2Cx, uint8_t slave_adr, uint8_t adr)
{
    int16_t ret = 0;
    uint32_t timeout = I2C1_TIMEOUT;

    // Start-Sequence
    I2C_GenerateSTART(I2Cx, ENABLE);

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_SB)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -1));
    }

    // ACK disable
    I2C_AcknowledgeConfig(I2Cx, DISABLE);

    // send slave-address (write)
    I2C_Send7bitAddress(I2Cx, slave_adr, I2C_Direction_Transmitter);

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_ADDR)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -2));
    }

    // clear ADDR-Flag
    I2Cx->SR2;

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_TXE)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -3));
    }

    // send address
    I2C_SendData(I2Cx, adr);

    timeout = I2C1_TIMEOUT;
    while((!I2C_GetFlagStatus(I2Cx, I2C_FLAG_TXE)) || (!I2C_GetFlagStatus(I2Cx, I2C_FLAG_BTF))) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -4));
    }

    // Start-Sequence
    I2C_GenerateSTART(I2Cx, ENABLE);

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_SB)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -5));
    }

    // send slave-address(read)
    I2C_Send7bitAddress(I2Cx, slave_adr, I2C_Direction_Receiver);

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_ADDR)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -6));
    }

    // clear ADDR-Flag
    I2Cx->SR2;

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_RXNE)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -7));
    }

    // Stop-Sequence
    I2C_GenerateSTOP(I2Cx, ENABLE);

    // read data
    ret = (int16_t)(I2C_ReceiveData(I2Cx));

    // ACK enable
    I2C_AcknowledgeConfig(I2Cx, ENABLE);

    return ret;
}

int16_t I2C1_ReadByte16(I2C_TypeDef* I2Cx, uint8_t slave_adr, uint8_t adr)
{
	return (I2C1_ReadByte(I2Cx, slave_adr, adr) << 8 | I2C1_ReadByte(I2Cx, slave_adr, adr));
}

int16_t I2C1_WriteByte(I2C_TypeDef* I2Cx, uint8_t slave_adr, uint8_t adr, uint8_t wert)
{
    uint32_t timeout = I2C1_TIMEOUT;

    // Start-Sequence
    I2C_GenerateSTART(I2Cx, ENABLE);

    timeout = I2C1_TIMEOUT;
    while(!I2C_GetFlagStatus(I2Cx, I2C_FLAG_SB)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -1));
    }

    // send slave-address (write)
    I2C_Send7bitAddress(I2Cx, slave_adr, I2C_Direction_Transmitter);

    timeout = I2C1_TIMEOUT;
    while (!I2C_GetFlagStatus(I2Cx, I2C_FLAG_ADDR)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -2));
    }

    // clear ADDR-Flag
    I2Cx->SR2;

    timeout = I2C1_TIMEOUT;
    while (!I2C_GetFlagStatus(I2Cx, I2C_FLAG_TXE)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -3));
    }

    // send address
    I2C_SendData(I2Cx, adr);

    timeout = I2C1_TIMEOUT;
    while (!I2C_GetFlagStatus(I2Cx, I2C_FLAG_TXE)) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -4));
    }

    // send data
    I2C_SendData(I2Cx, wert);

    timeout = I2C1_TIMEOUT;
    while ((!I2C_GetFlagStatus(I2Cx, I2C_FLAG_TXE)) || (!I2C_GetFlagStatus(I2Cx, I2C_FLAG_BTF))) {
        if(timeout != 0)
            timeout--;
        else
            return(I2C1_Timeout(I2Cx, -5));
    }

    // Stop-Sequence
    I2C_GenerateSTOP(I2Cx, ENABLE);

    return 0;
}

void I2C_Scan(I2C_TypeDef* I2Cx)
{
	int adr = 1, cnt = 0;

	d_printf("\fScanning...\r\n");

	for(adr = 1; adr < 127; adr++) {
		int16_t ret = I2C1_ReadByte(I2Cx, adr<<1, 0);
		if(ret >= 0) {
			d_printf("Found device at 0x%X\r\n", adr);
			cnt++;
		}
	}
	d_printf("Found %d devices\r\n", cnt);
}

static int8_t I2C1_Timeout(I2C_TypeDef* I2Cx, int8_t val)
{
    // Stop / Reset
    I2C_GenerateSTOP(I2Cx, ENABLE);
    I2C_SoftwareResetCmd(I2Cx, ENABLE);
    I2C_SoftwareResetCmd(I2Cx, DISABLE);

    // I2C deinit
    I2C_DeInit(I2Cx);

    if(I2C1 == I2Cx) {
		// I2C init
		I2C1_InitI2C();
    } else if(I2C2 == I2Cx) {
    	// I2C init
		I2C2_InitI2C();
    }

    return val;
}