/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 Matthias P. Braendli
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
*/


#include <stm32f4xx.h>
#include <stm32f4xx_usart.h>
#include <stm32f4xx_conf.h>

/* USART 3 on PD8 and PD9
 * See pio.txt for PIO allocation details */
const uint16_t GPIOD_PIN_USART3_TX = GPIO_Pin_8;
const uint16_t GPIOD_PIN_USART3_RX = GPIO_Pin_9;
const uint16_t GPIOD_PIN_GPS_RESET_N = GPIO_Pin_10;

/* USART 2 on PA2 and PA3 */
const uint16_t GPIOA_PIN_USART2_RX = GPIO_Pin_3;
const uint16_t GPIOA_PIN_USART2_TX = GPIO_Pin_2;

#include "GPIO/usart.h"

#define USART2_RECEIVE_ENABLE 1

void USART2_IRQHandler(void);
void USART3_IRQHandler(void);


void usart_init() {
    // ============== PC DEBUG USART ===========
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

    GPIO_InitTypeDef GPIO_InitStruct;
    GPIO_InitStruct.GPIO_Pin = GPIOA_PIN_USART2_RX | GPIOA_PIN_USART2_TX;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_USART2);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource3, GPIO_AF_USART2);

    // Setup USART2 for 9600,8,N,1
    USART_InitTypeDef USART_InitStruct;
    USART_InitStruct.USART_BaudRate = 9600;
    USART_InitStruct.USART_WordLength = USART_WordLength_8b;
    USART_InitStruct.USART_StopBits = USART_StopBits_1;
    USART_InitStruct.USART_Parity = USART_Parity_No;
    USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStruct.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
    USART_Init(USART2, &USART_InitStruct);

#if USART2_RECEIVE_ENABLE
    // enable the USART2 receive interrupt
    USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);

    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 6;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_SetPriority(USART2_IRQn, 6);
#endif

    // finally this enables the complete USART2 peripheral
    USART_Cmd(USART2, ENABLE);
}

void usart_gps_specific_init() {

    // ============== GPS USART ===========
    // Setup GPIO D and connect to USART 3
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);

    GPIO_InitTypeDef GPIO_InitStruct;
    GPIO_InitStruct.GPIO_Pin = GPIOD_PIN_USART3_RX | GPIOD_PIN_USART3_TX;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOD, &GPIO_InitStruct);

    GPIO_InitStruct.GPIO_Pin = GPIOD_PIN_GPS_RESET_N;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOD, &GPIO_InitStruct);

    // The GPS is put in RESET here, the GPS task will enable it
    GPIO_ResetBits(GPIOD, GPIOD_PIN_GPS_RESET_N);

    GPIO_PinAFConfig(GPIOD, GPIO_PinSource8, GPIO_AF_USART3);
    GPIO_PinAFConfig(GPIOD, GPIO_PinSource9, GPIO_AF_USART3);

    // Setup USART3 for 9600,8,N,1
    USART_InitTypeDef USART_InitStruct;
    USART_InitStruct.USART_BaudRate = 9600;
    USART_InitStruct.USART_WordLength = USART_WordLength_8b;
    USART_InitStruct.USART_StopBits = USART_StopBits_1;
    USART_InitStruct.USART_Parity = USART_Parity_No;
    USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStruct.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
    USART_Init(USART3, &USART_InitStruct);


    // enable the USART3 receive interrupt
    USART_ITConfig(USART3, USART_IT_RXNE, ENABLE);

    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 6;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_SetPriority(USART3_IRQn, 6);

    // finally this enables the complete USART3 peripheral
    USART_Cmd(USART3, ENABLE);
}

void usart_gps_remove_reset(void)
{
    GPIO_SetBits(GPIOD, GPIOD_PIN_GPS_RESET_N);
}

// Make sure Tasks are suspended when this is called!
void usart_puts(USART_TypeDef* USART, const char* str) {
    while(*str) {
        // wait until data register is empty
        USART_SendData(USART, *str);
        while(USART_GetFlagStatus(USART, USART_FLAG_TXE) == RESET) ;
        str++;
    }
}

void USART3_IRQHandler(void) {
    if (USART_GetITStatus(USART3, USART_IT_RXNE)) {
        char t = USART3->DR;
        usart_gps_process_char(t);
    }
}

void USART2_IRQHandler(void) {
    if (USART_GetITStatus(USART2, USART_IT_RXNE)) {
        char t = USART2->DR;
        usart_process_char(t);
    }
}