/*
 * ============ Platform Configuration ============
 */

#include <msp430.h>

#define EAP_RX_BUF              UCA0RXBUF
#define EAP_TX_BUF              UCA0TXBUF

#define EAP_RX_VECTOR           USCIAB0RX_VECTOR
#define EAP_TX_VECTOR           PORT2_VECTOR

#define EAP_RX_ACK_CONFIG()     (P2DIR |= BIT0)
#define EAP_RX_ACK_SET()        (P2OUT |= BIT0)
#define EAP_RX_ACK_CLR()        (P2OUT &= ~BIT0)

#define EAP_TX_INT_CONFIG()     (P2DIR &= ~BIT1, P2IES |= BIT1, P2IFG &= BIT1, P2IE |= BIT1)
#define EAP_TX_INT_TST()        (P2IFG & BIT1)
#define EAP_TX_INT_CLR()        (P2IFG &= ~BIT1)

void init(void) {
    
    WDTCTL = WDTPW + WDTHOLD;
    BCSCTL2 = SELM_0 + DIVM_0 + DIVS_0;
    if (CALBC1_1MHZ != 0xFF) {
        DCOCTL = 0x00;
        BCSCTL1 = CALBC1_1MHZ;      /* Set DCO to 1MHz */
        DCOCTL = CALDCO_1MHZ;
    }
    BCSCTL1 |= XT2OFF + DIVA_0;
    BCSCTL3 = XT2S_0 + LFXT1S_2 + XCAP_1;

    P1DIR |= BIT0;  /* LED */
    P1OUT &= ~BIT0;

    UCA0CTL1 |= UCSWRST;

    P1SEL |= BIT1 + BIT2;
    P1SEL2 |= BIT1 + BIT2;
	
    EAP_RX_ACK_CONFIG();
    EAP_RX_ACK_SET();
	
    EAP_TX_INT_CONFIG();

    UCA0CTL1 = UCSSEL_2 + UCSWRST;
    UCA0MCTL = UCBRF_0 + UCBRS_6;
    UCA0BR0 = 8;
    UCA0CTL1 &= ~UCSWRST;
    
    IFG2 &= ~(UCA0RXIFG);
    IE2 |= UCA0RXIE;

    __enable_interrupt();
}

/*
 * ============ Serial Driver ============
 */

#include <Em_Message.h>

__attribute__((interrupt(EAP_RX_VECTOR)))
static void rxHandler(void) {
    uint8_t b = EAP_RX_BUF;
    if (Em_Message_addByte(b)) {
        Em_Message_dispatch();
    }
    EAP_RX_ACK_CLR();
    EAP_RX_ACK_SET();
}

__attribute__((interrupt(EAP_TX_VECTOR)))
static void txHandler(void) {
    if (EAP_TX_INT_TST()) {
        uint8_t b;
        if (Em_Message_getByte(&b)) {
            EAP_TX_BUF = b;
        }
        EAP_TX_INT_CLR();
    }
}

void Em_Message_startSend() {
    uint8_t b;
    if (Em_Message_getByte(&b)) {
        UCA0TXBUF = b;
    }
}

uint8_t Em_Message_lock() {
    uint8_t key;
    asm ("MOV r2, %0": "=r" (key));
    key &= 0x8;
    asm ("DINT");
    return key;
}

void Em_Message_unlock(uint8_t key) {
    if (key) {
        asm ("EINT");
    }
    else {
        asm ("DINT");
    }
}

/*
 * ============ Application Program ============
 */

#include <FileTest.h>

int main(int argc, char *argv[]) {
    volatile int dummy = 0;
    init();
    FileTest_run();
    while (dummy == 0) {
        /* idle */
    }
    return 0;
}

FileTest_fileSize_t fileSizeVal;
int seed;

void FileTest_connectHandler(void) {
    P1OUT |= BIT0;
}

void FileTest_disconnectHandler(void) {
    P1OUT &= ~BIT0;
}

void FileTest_fileSize_fetch(FileTest_fileSize_t* const output) {
    *output = fileSizeVal;
}

void FileTest_fileSize_store(FileTest_fileSize_t* const input)
{
    fileSizeVal = *input;
}

uint16_t FileTest_fileData_fetch(FileTest_fileData_t* const output, int32_t offset, uint16_t count) {
    int32_t rem = fileSizeVal - offset;
    if (rem < count) {
        count = (uint16_t)rem;
    }
    uint16_t i;
    for (i = 0; i < count; i++) {
        output->elems[i] = (seed + (offset + i)) & 0xFF;
    }
    return count;
}

uint16_t FileTest_fileData_store(FileTest_fileData_t* const input, int32_t offset, uint16_t count) {
    if (offset == 0 && count) {
        seed = input->elems[0];
    }
    return count;
}