#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/spi.h>

#include <SEGGER_RTT.h>
#include <sx1276.h>

#include "delay.h"
#include "util.h"

uint8_t FIFO[FIFO_SIZE] = {0};

static void clock_setup(void)
{
    rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSE8_72MHZ]);

    rcc_periph_clock_enable(RCC_GPIOA);
    rcc_periph_clock_enable(RCC_GPIOB);

    rcc_periph_clock_enable(RCC_SPI1);
}

static void gpio_setup(void)
{
    gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_2_MHZ,
              GPIO_CNF_OUTPUT_PUSHPULL, GPIO0 | GPIO1);
}

static void spi_setup(void)
{
    /* Configure GPIOs: SS=PA4, SCK=PA5, MISO=PA6 and MOSI=PA7 */
    gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ,
                  GPIO_CNF_OUTPUT_ALTFN_PUSHPULL,
                  GPIO5 | GPIO7 );

    gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO4);
    gpio_set(GPIOA, GPIO4);

    gpio_set_mode(GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT,
                  GPIO6);

    /* Reset SPI, SPI_CR1 register cleared, SPI is disabled */
    spi_reset(SPI1);


    /* Set up SPI in Master mode with:
     * Clock baud rate: 1/64 of peripheral clock frequency
     * Clock polarity: Idle Low
     * Clock phase: Data valid on 1st clock pulse
     * Data frame format: 8-bit
     * Frame format: MSB First
     */
    spi_init_master(SPI1, SPI_CR1_BAUDRATE_FPCLK_DIV_64,
                    SPI_CR1_CPOL_CLK_TO_0_WHEN_IDLE,
                    SPI_CR1_CPHA_CLK_TRANSITION_1, SPI_CR1_DFF_8BIT, SPI_CR1_MSBFIRST);

    /*
     * Set NSS management to software.
     *
     * Note:
     * Setting nss high is very important, even if we are controlling the GPIO
     * ourselves this bit needs to be at least set to 1, otherwise the spi
     * peripheral will not send any data out.
     */
    spi_enable_software_slave_management(SPI1);
    spi_set_nss_high(SPI1);

    /* Enable SPI1 periph. */
    spi_enable(SPI1);
}

int main(void)
{
    clock_setup();
    spi_setup();
    gpio_setup();

    SEGGER_RTT_WriteString(0, "SX1276 LoRa test\n");
    SEGGER_RTT_printf(0, "CPU clk: %dHz\n", rcc_ahb_frequency);

    struct sx1276_state_st *sx1276_state = sx1276_init(86520000);

    sx1276_fifo_write(0x0, 0xde);
    sx1276_fifo_write(0x1, 0xad);
    sx1276_fifo_write(0x2, 0xbe);
    sx1276_fifo_write(0x3, 0xef);

    sx1276_write(SX1276_REG_PAYLOAD_LENGTH, 4);

    sx1276_write(SX1276_REG_OP_MODE, SX1276_MODE_LONG_RANGE_MODE | SX1276_MODE_TX);

    while (1) {
        int ret = sx1276_read(SX1276_REG_OP_MODE);
        SEGGER_RTT_printf(0, "MOD: 0x%02x ", ret);
        ret = sx1276_read(SX1276_REG_MODEM_STATUS);
        SEGGER_RTT_printf(0, "STAT: 0x%02x ", ret);
        ret = sx1276_read(SX1276_REG_IRQ_FLAGS);
        SEGGER_RTT_printf(0, "IRQ: 0x%02x\n", ret);
        if (ret & (1<<3)){
            break;
        }
        delay_ms(100);
    }
    SEGGER_RTT_printf(0, "Done\n");


    /* Blink the LED (PA5) on the board. */
    while (1) {

        /* Using API function gpio_toggle(): */
        gpio_toggle(GPIOB, GPIO1);	/* LED on/off */
        delay_ms(500);
    }

    return 0;
}