/* vi: set sw=4 ts=4: */
/*
 * Progress bar code.
 */
/* Original copyright notice which applies to the CONFIG_FEATURE_WGET_STATUSBAR stuff,
 * much of which was blatantly stolen from openssh.
 */
/*-
 * Copyright (c) 1992, 1993
 * The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. BSD Advertising Clause omitted per the July 22, 1999 licensing change
 *    ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
 *
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
#include "libbb.h"
#include "unicode.h"

enum {
        /* Seconds when xfer considered "stalled" */
        STALLTIME = 5
};

void FAST_FUNC bb_progress_init(bb_progress_t *p, const char *curfile)
{
#if ENABLE_UNICODE_SUPPORT
        init_unicode();
        p->curfile = unicode_conv_to_printable_fixedwidth(/*NULL,*/ curfile, 20);
#else
        p->curfile = curfile;
#endif
        p->start_sec = monotonic_sec();
        p->last_update_sec = p->start_sec;
        p->last_change_sec = p->start_sec;
        p->last_size = 0;
}

/* File already had beg_size bytes.
 * Then we started downloading.
 * We downloaded "transferred" bytes so far.
 * Download is expected to stop when total size (beg_size + transferred)
 * will be "totalsize" bytes.
 * If totalsize == 0, then it is unknown.
 */
void FAST_FUNC bb_progress_update(bb_progress_t *p,
                uoff_t beg_size,
                uoff_t transferred,
                uoff_t totalsize)
{
        uoff_t beg_and_transferred;
        unsigned since_last_update, elapsed;
        int notty;
        int kiloscale;

        //transferred = 1234; /* use for stall detection testing */
        //totalsize = 0; /* use for unknown size download testing */

        elapsed = monotonic_sec();
        since_last_update = elapsed - p->last_update_sec;
        p->last_update_sec = elapsed;

        if (totalsize != 0 && transferred >= totalsize - beg_size) {
                /* Last call. Do not skip this update */
                transferred = totalsize - beg_size; /* sanitize just in case */
        }
        else if (since_last_update == 0) {
                /*
                 * Do not update on every call
                 * (we can be called on every network read!)
                 */
                return;
        }

        kiloscale = 0;
        /*
         * Scale sizes down if they are close to overflowing.
         * This allows calculations like (100 * transferred / totalsize)
         * without risking overflow: we guarantee 10 highest bits to be 0.
         * Introduced error is less than 1 / 2^12 ~= 0.025%
         */
        if (ULONG_MAX > 0xffffffff || sizeof(off_t) == 4 || sizeof(off_t) != 8) {
                /*
                 * 64-bit CPU || small off_t: in either case,
                 * >> is cheap, single-word operation.
                 * ... || strange off_t: also use this code
                 * (it is safe, just suboptimal wrt code size),
                 * because 32/64 optimized one works only for 64-bit off_t.
                 */
                if (totalsize >= (1 << 22)) {
                        totalsize >>= 10;
                        beg_size >>= 10;
                        transferred >>= 10;
                        kiloscale = 1;
                }
        } else {
                /* 32-bit CPU and 64-bit off_t.
                 * Use a 40-bit shift, it is easier to do on 32-bit CPU.
                 */
/* ONE suppresses "warning: shift count >= width of type" */
#define ONE (sizeof(off_t) > 4)
                if (totalsize >= (uoff_t)(1ULL << 54*ONE)) {
                        totalsize = (uint32_t)(totalsize >> 32*ONE) >> 8;
                        beg_size = (uint32_t)(beg_size >> 32*ONE) >> 8;
                        transferred = (uint32_t)(transferred >> 32*ONE) >> 8;
                        kiloscale = 4;
                }
        }

        notty = !isatty(STDERR_FILENO);

        if (ENABLE_UNICODE_SUPPORT)
                fprintf(stderr, "\r%s" + notty, p->curfile);
        else
                fprintf(stderr, "\r%-20.20s" + notty, p->curfile);

        beg_and_transferred = beg_size + transferred;

        if (totalsize != 0) {
                int barlength;
                unsigned ratio = 100 * beg_and_transferred / totalsize;
                fprintf(stderr, "%4u%%", ratio);

                barlength = get_terminal_width(2) - 49;
                if (barlength > 0) {
                        /* god bless gcc for variable arrays :) */
                        char buf[barlength + 1];
                        unsigned stars = (unsigned)barlength * beg_and_transferred / totalsize;
                        memset(buf, ' ', barlength);
                        buf[barlength] = '\0';
                        memset(buf, '*', stars);
                        fprintf(stderr, " |%s|", buf);
                }
        }

        while (beg_and_transferred >= 100000) {
                beg_and_transferred >>= 10;
                kiloscale++;
        }
        /* see http://en.wikipedia.org/wiki/Tera */
        fprintf(stderr, "%6u%c", (unsigned)beg_and_transferred, " kMGTPEZY"[kiloscale]);
#define beg_and_transferred dont_use_beg_and_transferred_below()

        since_last_update = elapsed - p->last_change_sec;
        if ((unsigned)transferred != p->last_size) {
                p->last_change_sec = elapsed;
                p->last_size = (unsigned)transferred;
                if (since_last_update >= STALLTIME) {
                        /* We "cut out" these seconds from elapsed time
                         * by adjusting start time */
                        p->start_sec += since_last_update;
                }
                since_last_update = 0; /* we are un-stalled now */
        }

        elapsed -= p->start_sec; /* now it's "elapsed since start" */

        if (since_last_update >= STALLTIME) {
                fprintf(stderr, "  - stalled -");
        } else if (!totalsize || !transferred || (int)elapsed < 0) {
                fprintf(stderr, " --:--:-- ETA");
        } else {
                unsigned eta, secs, hours;

                totalsize -= beg_size; /* now it's "total to upload" */

                /* Estimated remaining time =
                 * estimated_sec_to_dl_totalsize_bytes - elapsed_sec =
                 * totalsize / average_bytes_sec_so_far - elapsed =
                 * totalsize / (transferred/elapsed) - elapsed =
                 * totalsize * elapsed / transferred - elapsed
                 */
                eta = totalsize * elapsed / transferred - elapsed;
                if (eta >= 1000*60*60)
                        eta = 1000*60*60 - 1;
                secs = eta % 3600;
                hours = eta / 3600;
                fprintf(stderr, "%3u:%02u:%02u ETA", hours, secs / 60, secs % 60);
        }
        if (notty)
                fputc('\n', stderr);
}