/*
 * =====================================================================================
 *
 * ________        .__        __    ________               ____  ________
 * \_____  \  __ __|__| ____ |  | __\______ \   _______  _/_   |/  _____/
 *  /  / \  \|  |  \  |/ ___\|  |/ / |    |  \_/ __ \  \/ /|   /   __  \
 * /   \_/.  \  |  /  \  \___|    <  |    `   \  ___/\   / |   \  |__\  \
 * \_____\ \_/____/|__|\___  >__|_ \/_______  /\___  >\_/  |___|\_____  /
 *        \__>             \/     \/        \/     \/                 \/
 *
 *                                  www.optixx.org
 *
 *
 *        Version:  1.0
 *        Created:  07/21/2009 03:32:16 PM
 *         Author:  david@optixx.org
 *
 * =====================================================================================
 */


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

#include "sram.h"
#include "debug.h"
#include "info.h"

#define RUNCHAR 0x90

uint8_t rle_decode(PGM_VOID_P in_addr, int32_t in_len, uint32_t out_addr)
{
    uint8_t in_byte, in_repeat, last_byte;
    uint32_t out_len, out_len_left;
    info("RLE decode len=%li addr=0x%08lx\n", in_len, out_addr);
    last_byte = 0;

    out_len_left = out_len;
    sram_bulk_write_start(out_addr);
#define INBYTE(b) \
	do { \
	         if ( --in_len < 0 ) { \
			   return 1; \
		 } \
         cli();\
         b = pgm_read_byte((PGM_VOID_P)in_addr++);  \
         sei();\
	} while(0)

#define OUTBYTE(b) \
	do { \
        sram_bulk_write(b);\
        sram_bulk_write_next();\
        out_addr++;\
	} while(0)

    INBYTE(in_byte);

    if (in_byte == RUNCHAR) {
        INBYTE(in_repeat);
        if (in_repeat != 0) {
            info("Orphaned RLE code at start\n");
            return 1;
        }
        OUTBYTE(RUNCHAR);
    } else {
        OUTBYTE(in_byte);
    }

    while (in_len > 0) {
        INBYTE(in_byte);
        if (in_len % 1024 == 0)
            info(".");
        if (in_byte == RUNCHAR) {
            INBYTE(in_repeat);
            if (in_repeat == 0) {
                /*
                 * Just an escaped RUNCHAR value 
                 */
                OUTBYTE(RUNCHAR);
            } else {
                /*
                 * Pick up value and output a sequence of it 
                 */
                in_byte = last_byte;    // ;out_data[-1];
                while (--in_repeat > 0)
                    OUTBYTE(in_byte);
            }
        } else {
            /*
             * Normal byte 
             */
            OUTBYTE(in_byte);
        }
        last_byte = in_byte;
    }
    sram_bulk_write_end();
    return 0;
}