#include <avr/io.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>  /* for sei() */
#include <util/delay.h>     /* for _delay_ms() */
#include <stdlib.h>
#include <avr/pgmspace.h>   /* required by usbdrv.h */

#include "usbdrv.h"
#include "oddebug.h"        /* This is also an example for using debug macros */
#include "requests.h"       /* The custom request numbers we use */
#include "uart.h"
#include "sram.h"
#include "debug.h"
#include "crc.h"


#define REQ_IDLE      0
#define REQ_UPLOAD    1
#define RES_CRC       2
#define BUFFER_SIZE 256

extern FILE uart_stdout;

uint8_t     read_buffer[BUFFER_SIZE];
uint32_t    req_addr = 0;
uint32_t     req_size; 
uint8_t     req_bank; 
uint32_t    req_bank_size; 
uint8_t     req_state = REQ_IDLE;
uint8_t     rx_remaining = 0;
uint8_t     tx_remaining = 0;
uint16_t    sync_errors = 0;
uint8_t     tx_buffer[32];  
uint8_t     data_buffer[4];  
uint32_t    addr;

void crc_check_memory(uint32_t top_addr){
 	uint16_t crc = 0;
    uint32_t addr;
 	req_bank = 0;
    for (addr=0x000000; addr < top_addr; addr+=BUFFER_SIZE) {
    	sram_read_buffer(addr,read_buffer,BUFFER_SIZE);
    	crc = do_crc_update(crc,read_buffer,BUFFER_SIZE);
    	if (addr && addr%32768 == 0){
    	    printf("crc_check_memory: req_bank: 0x%x Addr: 0x%lx CRC: %x\n",req_bank,addr,crc);
            req_bank++;
    		crc = 0;
    	}
    }
}


void crc_check_memory_range(uint32_t start_addr,uint32_t size){
 	uint16_t crc = 0;
    uint32_t addr;
 	req_bank = 0;
    for (addr=start_addr; addr < start_addr + size; addr+=BUFFER_SIZE) {
    	sram_read_buffer(addr,read_buffer,BUFFER_SIZE);
    	crc = do_crc_update(crc,read_buffer,BUFFER_SIZE);
    }	
    tx_buffer[0] = crc & 0xff;
    tx_buffer[1] = (crc >> 8) & 0xff;
    printf("crc_check_memory_range: Addr: 0x%lx CRC: %x\n",addr,crc);
}


usbMsgLen_t usbFunctionSetup(uchar data[8]){
    
    usbRequest_t    *rq = (void *)data;
    uint8_t ret_len = 0;
    if(rq->bRequest == USB_UPLOAD_INIT){
        req_bank =0;
        rx_remaining=0;
        req_bank_size= 1 << rq->wValue.word;
        sync_errors=0;
        printf("USB_UPLOAD_INIT: bank size %li\n",req_bank_size);
    }else if(rq->bRequest == USB_UPLOAD_ADDR){ /* echo -- used for reliability tests */
        req_state = REQ_UPLOAD;
        req_addr = rq->wValue.word;
        req_addr = req_addr << 16;
        req_addr = req_addr | rq->wIndex.word;
        if (rx_remaining){
            sync_errors++;
            printf("USB_UPLOAD_ADDR: Out of sync Addr=0x%lx remain=%i packet=%i sync_error=%i\n",req_addr,rx_remaining,rq->wLength.word,sync_errors );  
            ret_len=0;
        }    
        rx_remaining  = rq->wLength.word;
        ret_len = 0xff;
        if (req_addr && req_addr % req_bank_size== 0){
		    printf("USB_UPLOAD_ADDR: req_bank: 0x%x Addr: 0x%08lx \n",req_bank,req_addr);
            req_bank++;
		}
        ret_len=0xff;
    }else if(rq->bRequest == USB_DOWNLOAD_INIT){
        printf("USB_DOWNLOAD_INIT\n");
    }else if(rq->bRequest == USB_DOWNLOAD_ADDR){
        printf("USB_DOWNLOAD_ADDR\n");
    }else if(rq->bRequest == USB_CRC){
        req_addr = rq->wValue.word;
        req_addr = req_addr << 16;
        req_addr = req_addr | rq->wIndex.word;
        printf("USB_CRC: Addr 0x%lx \n", req_addr);  
        cli();
        crc_check_memory(req_addr);
        sei();
    }else if(rq->bRequest == USB_CRC_ADDR){
        req_addr = rq->wValue.word;
        req_addr = req_addr << 16;
        req_addr = req_addr | rq->wIndex.word;
        printf("USB_CRC_ADDR: Addr: 0x%lx Size: %i\n", req_addr,rq->wLength.word);  
        req_size = rq->wLength.word;
        req_size = req_size << 2;
        tx_remaining = 2;
        printf("USB_CRC_ADDR: Addr: 0x%lx Size: %li\n", req_addr,req_size);  
        cli();
        //crc_check_memory_range(req_addr,req_size);
        sei();
        ret_len=2;
    }
    
    usbMsgPtr = data_buffer;
    return ret_len;   /* default for not implemented requests: return no data back to host */
}


uint8_t usbFunctionWrite(uint8_t *data, uint8_t len)
{
    if (len > rx_remaining){
         printf("usbFunctionWrite more data than expected remain: %i len: %i\n",rx_remaining,len);
         len = rx_remaining;
     }
     if (req_state==REQ_UPLOAD){
    
        rx_remaining -= len;
        #if 1  
        printf("usbFunctionWrite addr: 0x%08lx len: %i rx_remaining=%i\n",req_addr,len,rx_remaining);
        #endif    
        cli();
        sram_copy(req_addr,data,len);
        sei();
        req_addr +=len;
    }
    return len;
}

uint8_t usbFunctionRead(uint8_t *data, uint8_t len)
{
    uint8_t i;
    if(len > tx_remaining)
        len = tx_remaining;
    tx_remaining -= len;
    #if 1    
    printf("usbFunctionRead len=%i tx_remaining=%i \n",len,tx_remaining);
    #endif    
    for (i = 0; i < len; i++) {
        *data = tx_buffer[len];
        data++;
    }
    return len;
}

/* ------------------------------------------------------------------------- */

int main(void)
{
    uint8_t i;
    wdt_enable(WDTO_1S);
    uart_init();
    stdout = &uart_stdout;
    sram_init();
 	printf("SRAM Init\n");
 	spi_init();
 	printf("SPI Init\n");
    usbInit();
 	printf("USB Init\n");
    usbDeviceDisconnect();  /* enforce re-enumeration, do this while interrupts are disabled! */
 	printf("USB disconnect\n");
    i = 10;
    while(--i){             /* fake USB disconnect for > 250 ms */
        wdt_reset();
        _delay_ms(1);
    }
    usbDeviceConnect();
 	printf("USB connect\n");
    sei();
 	printf("USB poll\n");
    for(;;){                /* main event loop */
        wdt_reset();
        usbPoll();
    }
    return 0;
}

/* ------------------------------------------------------------------------- */