/* libutf8/src/tests/random.c
 *
 *  (c)2006, Laurence Withers. Released under the GNU GPL. See file
 *  COPYING for more information / terms of license.
*/

#include "utf8.h"

#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>



void make_rand(wchar_t* buf, int ch)
{
    int fd = open("/dev/urandom", O_RDONLY);
    if(fd < 0) {
        perror("open(\"/dev/urandom\")");
        exit(1);
    }
    ch *= sizeof(wchar_t);
    if(read(fd, (char*)buf, ch) != ch) {
        perror("read(\"/dev/urandom\")");
        exit(1);
    }
    close(fd);

    ch /= sizeof(wchar_t);
    while(ch--) {
        buf[ch] &= 0x7FFFFFFF;
    }
}



int do_encode(char* dest, size_t size, wchar_t* src, size_t amt)
{
    struct utf8_encode_state ctx;
    memset(&ctx, 0, sizeof(ctx));

    ctx.rd = src;
    ctx.rd_remain = amt;
    ctx.wr = dest;
    ctx.wr_size = 20;

    while(ctx.rd_remain) {
        if(!utf8_encoder(&ctx)) {
            perror("utf8_encoder");
            exit(1);
        }

        ctx.wr += ctx.written;
        if(ctx.wr + ctx.wr_size > dest + size) {
            fprintf(stderr, "do_encode: we're going to run out of memory\n");
            exit(1);
        }
    }

    return ctx.wr - dest;
}



int MIN(int x, int y)
{
    return (x < y) ? x : y;
}



void do_decode_easy(wchar_t* dest, size_t size, const char* src, size_t amt)
{
    struct utf8_decode_state ctx;
    memset(&ctx, 0, sizeof(ctx));

    ctx.rd = src;
    ctx.rd_remain = amt;
    ctx.wr = dest;
    ctx.wr_size = size;

    if(!utf8_decoder(&ctx)) {
        perror("[easy] utf8_decoder");
        exit(1);
    }

    if(ctx.rd_remain) {
        fprintf(stderr, "do_decode_easy: %d bytes left in buffer\n", ctx.rd_remain);
        exit(1);
    }

    if(!ctx.complete) {
        fprintf(stderr, "do_decode_easy: incomplete character at end of data\n");
        exit(1);
    }
}



void do_decode(wchar_t* dest, size_t size, const char* src, size_t amt)
{
    struct utf8_decode_state ctx;
    memset(&ctx, 0, sizeof(ctx));

    ctx.rd = src;
    ctx.rd_remain = MIN(20, amt);
    amt -= ctx.rd_remain;
    ctx.wr = dest;
    ctx.wr_size = 20;

    while(ctx.rd_remain) {
        if(!utf8_decoder(&ctx)) {
            perror("utf8_decoder");
            exit(1);
        }

        if(!ctx.rd_remain) {
            ctx.rd_remain = MIN(20, amt);
            amt -= ctx.rd_remain;
        }

        ctx.wr += ctx.written;
        if(ctx.wr + ctx.wr_size > dest + size) {
            ctx.wr_size = ctx.wr - dest - size;
        }
    }
}



int main(int argc, char* argv[])
{
    wchar_t wbuf[1024], wbuf2[1025];
    char cbuf[8192];
    int amt;

    if(argc == 2 && !strcmp(argv[1], "--print-summary")) {
        printf("Encodes and decodes random well-formed strings.\n");
        return 0;
    }

    make_rand(wbuf, 1024);
    amt = do_encode(cbuf, 8192, wbuf, 1024);
    do_decode_easy(wbuf2, 1025, cbuf, amt);
    do_decode(wbuf2, 1025, cbuf, amt);

    if(memcmp(wbuf, wbuf2, 1024 * sizeof(wchar_t))) {
        fprintf(stderr, "Output doesn't match input!\n");
        for(amt = 0; amt < 1024; ++amt) {
            if(wbuf[amt] != wbuf2[amt])
                fprintf(stderr, "%4d: %08X != %08X\n", amt, wbuf[amt], wbuf2[amt]);
        }
        return 1;
    }

    printf("Success.\n");
    return 0;
}


/* options for text editors
kate: replace-trailing-space-save true; space-indent true; tab-width 4;
*/