/*      $NetBSD: wav.c,v 1.24 2024/03/20 20:18:39 mrg Exp $     */

/*
 * Copyright (c) 2002, 2009, 2013, 2015, 2019, 2024 Matthew R. Green
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/*
 * WAV support for the audio tools; thanks go to the sox utility for
 * clearing up issues with WAV files.
 */
#include <sys/cdefs.h>

#ifndef lint
__RCSID("$NetBSD: wav.c,v 1.24 2024/03/20 20:18:39 mrg Exp $");
#endif


#include <sys/types.h>
#include <sys/audioio.h>
#include <sys/ioctl.h>
#include <sys/time.h>

#include <ctype.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <unistd.h>
#include <stdbool.h>

#include "libaudio.h"
#include "auconv.h"

static const struct {
        int     wenc;
        const char *wname;
} wavencs[] = {
        { WAVE_FORMAT_UNKNOWN,  "Microsoft Official Unknown" },
        { WAVE_FORMAT_PCM,      "Microsoft PCM" },
        { WAVE_FORMAT_ADPCM,    "Microsoft ADPCM" },
        { WAVE_FORMAT_IEEE_FLOAT,"Microsoft IEEE Floating-Point" },
        { WAVE_FORMAT_ALAW,     "Microsoft A-law" },
        { WAVE_FORMAT_MULAW,    "Microsoft mu-law" },
        { WAVE_FORMAT_OKI_ADPCM,"OKI ADPCM" },
        { WAVE_FORMAT_DIGISTD,  "Digistd format" },
        { WAVE_FORMAT_DIGIFIX,  "Digifix format" },
        { -1,                   "?Unknown?" },
};

const char *
wav_enc_from_val(int encoding)
{
        int     i;

        for (i = 0; wavencs[i].wenc != -1; i++)
                if (wavencs[i].wenc == encoding)
                        break;
        return (wavencs[i].wname);
}

/*
 * sample header is:
 *
 *   RIFF\^@^C^@WAVEfmt ^P^@^@^@^A^@^B^@D<AC>^@^@^P<B1>^B^@^D^@^P^@data^@^@^C^@^@^@^@^@^@^@^@^@^@
 *
 */
/*
 * WAV format helpers
 */

#define RIFFNAMELEN     4

static bool
find_riff_chunk(const char *search, size_t *remainp, char **wherep, uint32_t *partlen)
{
        wav_audioheaderpart part;

        *partlen = 0;

#define ADJUST(l) do {                          \
        if (l > *(remainp))                     \
                return false;                   \
        *(wherep) += (l);                       \
        *(remainp) -= (l);                      \
} while (0)

        while (*remainp >= sizeof part) {
                const char *emsg = "";
                uint32_t len;

                memcpy(&part, *wherep, sizeof part);
                ADJUST(sizeof part);
                len = getle32(part.len);
                if (len % 2) {
                        emsg = " (odd length, adjusted)";
                        len += 1;
                }
                if (strncmp(part.name, search, RIFFNAMELEN) == 0) {
                        *partlen = len;
                        if (verbose > 1)
                                fprintf(stderr, "Found part %.04s length %d%s\n",
                                    part.name, len, emsg);
                        return true;
                }
                ADJUST(len);
                if (verbose > 1)
                        fprintf(stderr, "Skipping part %.04s length %d%s\n",
                            part.name, len, emsg);
        }
#undef ADJUST

        return false;
}

/*
 * find a .wav header, etc. returns header length on success
 */
ssize_t
audio_wav_parse_hdr(void *hdr, size_t sz, u_int *enc, u_int *prec,
    u_int *sample, u_int *channels, off_t *datasize)
{
        char    *where = hdr;
        wav_audioheaderfmt fmt;
        wav_audiohdrextensible ext;
        size_t remain = sz;
        u_int   newenc, newprec;
        uint32_t len = 0;
        u_int16_t fmttag;
        static const char
            strfmt[RIFFNAMELEN] = "fmt ",
            strRIFF[RIFFNAMELEN] = "RIFF",
            strWAVE[RIFFNAMELEN] = "WAVE",
            strdata[RIFFNAMELEN] = "data";
        bool found;

        if (sz < 32)
                return (AUDIO_ENOENT);

#define ADJUST(l) do {                          \
        if ((l) > remain)                       \
                return (AUDIO_ESHORTHDR);       \
        where += (l);                           \
        remain -= (l);                          \
} while (0)

        if (memcmp(where, strRIFF, sizeof strRIFF) != 0)
                return (AUDIO_ENOENT);
        ADJUST(sizeof strRIFF);
        /* XXX we ignore the RIFF length here */
        ADJUST(4);
        if (memcmp(where, strWAVE, sizeof strWAVE) != 0)
                return (AUDIO_ENOENT);
        ADJUST(sizeof strWAVE);

        found = find_riff_chunk(strfmt, &remain, &where, &len);

        /* too short ? */
        if (!found || remain <= sizeof fmt)
                return (AUDIO_ESHORTHDR);

        memcpy(&fmt, where, sizeof fmt);
        fmttag = getle16(fmt.tag);
        if (verbose)
                printf("WAVE format tag/len: %04x/%u\n", fmttag, len);

        if (fmttag == WAVE_FORMAT_EXTENSIBLE) {
                if (len < sizeof(fmt) + sizeof(ext)) {
                        if (verbose)
                                fprintf(stderr, "short WAVE ext fmt\n");
                        return (AUDIO_ESHORTHDR);
                }
                if (remain <= sizeof ext + sizeof fmt) {
                        if (verbose)
                                fprintf(stderr, "WAVE ext truncated\n");
                        return (AUDIO_ESHORTHDR);
                }
                memcpy(&ext, where + sizeof fmt, sizeof ext);
                fmttag = getle16(ext.sub_tag);
                uint16_t sublen = getle16(ext.len);
                if (verbose)
                        printf("WAVE extensible tag/len: %04x/%u\n", fmttag, sublen);

                /*
                 * XXXMRG: it may be that part.len (aka sizeof fmt + sizeof ext)
                 * should equal sizeof fmt + sizeof ext.len + sublen?  this block
                 * is only entered for part.len == 40, where ext.len is expected
                 * to be 22 (sizeof ext.len = 2, sizeof fmt = 16).
                 *
                 * warn about this, but don't consider it an error.
                 */
                if (getle16(ext.len) != 22 && verbose) {
                        fprintf(stderr, "warning: WAVE ext.len %u not 22\n",
                            getle16(ext.len));
                }
        } else if (len < sizeof(fmt)) {
                if (verbose)
                        fprintf(stderr, "WAVE fmt unsupported size %u\n", len);
                return (AUDIO_EWAVUNSUPP);
        }
        ADJUST(len);

        switch (fmttag) {
        default:
                return (AUDIO_EWAVUNSUPP);

        case WAVE_FORMAT_PCM:
        case WAVE_FORMAT_ADPCM:
        case WAVE_FORMAT_OKI_ADPCM:
        case WAVE_FORMAT_IMA_ADPCM:
        case WAVE_FORMAT_DIGIFIX:
        case WAVE_FORMAT_DIGISTD:
                switch (getle16(fmt.bits_per_sample)) {
                case 8:
                        newprec = 8;
                        break;
                case 16:
                        newprec = 16;
                        break;
                case 24:
                        newprec = 24;
                        break;
                case 32:
                        newprec = 32;
                        break;
                default:
                        return (AUDIO_EWAVBADPCM);
                }
                if (newprec == 8)
                        newenc = AUDIO_ENCODING_ULINEAR_LE;
                else
                        newenc = AUDIO_ENCODING_SLINEAR_LE;
                break;
        case WAVE_FORMAT_ALAW:
                newenc = AUDIO_ENCODING_ALAW;
                newprec = 8;
                break;
        case WAVE_FORMAT_MULAW:
                newenc = AUDIO_ENCODING_ULAW;
                newprec = 8;
                break;
        case WAVE_FORMAT_IEEE_FLOAT:
                switch (getle16(fmt.bits_per_sample)) {
                case 32:
                        newenc = AUDIO_ENCODING_LIBAUDIO_FLOAT32;
                        newprec = 32;
                        break;
                case 64:
                        newenc = AUDIO_ENCODING_LIBAUDIO_FLOAT64;
                        newprec = 32;
                        break;
                default:
                        return (AUDIO_EWAVBADPCM);
                }
                break;
        }

        found = find_riff_chunk(strdata, &remain, &where, &len);
        if (!found)
                return (AUDIO_EWAVNODATA);

        if (channels)
                *channels = (u_int)getle16(fmt.channels);
        if (sample)
                *sample = getle32(fmt.sample_rate);
        if (enc)
                *enc = newenc;
        if (prec)
                *prec = newprec;
        if (datasize)
                *datasize = (off_t)len;
        return (where - (char *)hdr);

#undef ADJUST
}


/*
 * prepare a WAV header for writing; we fill in hdrp, lenp and leftp,
 * and expect our caller (wav_write_header()) to use them.
 */
int
wav_prepare_header(struct track_info *ti, void **hdrp, size_t *lenp, int *leftp)
{
        /*
         * WAV header we write looks like this:
         *
         *      bytes   purpose
         *      0-3     "RIFF"
         *      4-7     RIFF chunk length (file length minus 8)
         *      8-15    "WAVEfmt "
         *      16-19   format size
         *      20-21   format tag
         *      22-23   number of channels
         *      24-27   sample rate
         *      28-31   average bytes per second
         *      32-33   block alignment
         *      34-35   bits per sample
         *
         * then for ULAW and ALAW outputs, we have an extended chunk size
         * and a WAV "fact" to add:
         *
         *      36-37   length of extension (== 0)
         *      38-41   "fact"
         *      42-45   fact size
         *      46-49   number of samples written
         *      50-53   "data"
         *      54-57   data length
         *      58-     raw audio data
         *
         * for PCM outputs we have just the data remaining:
         *
         *      36-39   "data"
         *      40-43   data length
         *      44-     raw audio data
         *
         *      RIFF\^@^C^@WAVEfmt ^P^@^@^@^A^@^B^@D<AC>^@^@^P<B1>^B^@^D^@^P^@data^@^@^C^@^@^@^@^@^@^@^@^@^@
         */
        static char wavheaderbuf[64];
        char    *p = wavheaderbuf;
        const char *riff = "RIFF",
            *wavefmt = "WAVEfmt ",
            *fact = "fact",
            *data = "data";
        u_int32_t filelen, fmtsz, sps, abps, factsz = 4, nsample, datalen;
        u_int16_t fmttag, nchan, align, extln = 0;

        if (ti->header_info)
                warnx("header information not supported for WAV");
        *leftp = 0;

        switch (ti->precision) {
        case 8:
                break;
        case 16:
                break;
        case 24:
                break;
        case 32:
                break;
        default:
                {
                        static int warned = 0;

                        if (warned == 0) {
                                warnx("can not support precision of %d", ti->precision);
                                warned = 1;
                        }
                }
                return (-1);
        }

        switch (ti->encoding) {
        case AUDIO_ENCODING_ULAW:
                fmttag = WAVE_FORMAT_MULAW;
                fmtsz = 18;
                align = ti->channels;
                break;

        case AUDIO_ENCODING_ALAW:
                fmttag = WAVE_FORMAT_ALAW;
                fmtsz = 18;
                align = ti->channels;
                break;

        /*
         * we could try to support RIFX but it seems to be more portable
         * to output little-endian data for WAV files.
         */
        case AUDIO_ENCODING_ULINEAR_BE:
        case AUDIO_ENCODING_SLINEAR_BE:
        case AUDIO_ENCODING_ULINEAR_LE:
        case AUDIO_ENCODING_SLINEAR_LE:
        case AUDIO_ENCODING_PCM16:

#if BYTE_ORDER == LITTLE_ENDIAN
        case AUDIO_ENCODING_ULINEAR:
        case AUDIO_ENCODING_SLINEAR:
#endif
                fmttag = WAVE_FORMAT_PCM;
                fmtsz = 16;
                align = ti->channels * (ti->precision / 8);
                break;

        default:
#if 0 // move into record.c, and maybe merge.c
                {
                        static int warned = 0;

                        if (warned == 0) {
                                const char *s = wav_enc_from_val(ti->encoding);

                                if (s == NULL)
                                        warnx("can not support encoding of %s", s);
                                else
                                        warnx("can not support encoding of %d", ti->encoding);
                                warned = 1;
                        }
                }
#endif
                ti->format = AUDIO_FORMAT_NONE;
                return (-1);
        }

        nchan = ti->channels;
        sps = ti->sample_rate;

        /* data length */
        if (ti->outfd == STDOUT_FILENO)
                datalen = 0;
        else if (ti->total_size != -1)
                datalen = ti->total_size;
        else
                datalen = 0;

        /* file length */
        filelen = 4 + (8 + fmtsz) + (8 + datalen);
        if (fmttag != WAVE_FORMAT_PCM)
                filelen += 8 + factsz;

        abps = (double)align*ti->sample_rate / (double)1 + 0.5;

        nsample = (datalen / ti->precision) / ti->sample_rate;

        /*
         * now we've calculated the info, write it out!
         */
#define put32(x) do { \
        u_int32_t _f; \
        putle32(_f, (x)); \
        memcpy(p, &_f, 4); \
} while (0)
#define put16(x) do { \
        u_int16_t _f; \
        putle16(_f, (x)); \
        memcpy(p, &_f, 2); \
} while (0)
        memcpy(p, riff, 4);
        p += 4;                         /* 4 */
        put32(filelen);
        p += 4;                         /* 8 */
        memcpy(p, wavefmt, 8);
        p += 8;                         /* 16 */
        put32(fmtsz);
        p += 4;                         /* 20 */
        put16(fmttag);
        p += 2;                         /* 22 */
        put16(nchan);
        p += 2;                         /* 24 */
        put32(sps);
        p += 4;                         /* 28 */
        put32(abps);
        p += 4;                         /* 32 */
        put16(align);
        p += 2;                         /* 34 */
        put16(ti->precision);
        p += 2;                         /* 36 */
        /* NON PCM formats have an extended chunk; write it */
        if (fmttag != WAVE_FORMAT_PCM) {
                put16(extln);
                p += 2;                 /* 38 */
                memcpy(p, fact, 4);
                p += 4;                 /* 42 */
                put32(factsz);
                p += 4;                 /* 46 */
                put32(nsample);
                p += 4;                 /* 50 */
        }
        memcpy(p, data, 4);
        p += 4;                         /* 40/54 */
        put32(datalen);
        p += 4;                         /* 44/58 */
#undef put32
#undef put16

        *hdrp = wavheaderbuf;
        *lenp = (p - wavheaderbuf);

        return 0;
}

write_conv_func
wav_write_get_conv_func(struct track_info *ti)
{
        write_conv_func conv_func = NULL;

        switch (ti->encoding) {

        /*
         * we could try to support RIFX but it seems to be more portable
         * to output little-endian data for WAV files.
         */
        case AUDIO_ENCODING_ULINEAR_BE:
#if BYTE_ORDER == BIG_ENDIAN
        case AUDIO_ENCODING_ULINEAR:
#endif
                if (ti->precision == 16)
                        conv_func = change_sign16_swap_bytes_be;
                else if (ti->precision == 32)
                        conv_func = change_sign32_swap_bytes_be;
                break;

        case AUDIO_ENCODING_SLINEAR_BE:
#if BYTE_ORDER == BIG_ENDIAN
        case AUDIO_ENCODING_SLINEAR:
#endif
                if (ti->precision == 8)
                        conv_func = change_sign8;
                else if (ti->precision == 16)
                        conv_func = swap_bytes;
                else if (ti->precision == 32)
                        conv_func = swap_bytes32;
                break;

        case AUDIO_ENCODING_ULINEAR_LE:
#if BYTE_ORDER == LITTLE_ENDIAN
        case AUDIO_ENCODING_ULINEAR:
#endif
                if (ti->precision == 16)
                        conv_func = change_sign16_le;
                else if (ti->precision == 32)
                        conv_func = change_sign32_le;
                break;

        case AUDIO_ENCODING_SLINEAR_LE:
        case AUDIO_ENCODING_PCM16:
#if BYTE_ORDER == LITTLE_ENDIAN
        case AUDIO_ENCODING_SLINEAR:
#endif
                if (ti->precision == 8)
                        conv_func = change_sign8;
                break;

        default:
                ti->format = AUDIO_FORMAT_NONE;
        }

        return conv_func;
}