/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
 * Copyright (c) 1999 Cameron Grant <cg@FreeBSD.org>
 * All rights reserved.
 * Copyright (c) 2024-2025 The FreeBSD Foundation
 *
 * Portions of this software were developed by Christos Margiolis
 * <christos@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
 *
 * 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 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 AUTHOR 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.
 */

#ifdef HAVE_KERNEL_OPTION_HEADERS
#include "opt_snd.h"
#endif

#include <dev/sound/pcm/sound.h>

#include "feeder_if.h"

static MALLOC_DEFINE(M_FEEDER, "feeder", "pcm feeder");

static SLIST_HEAD(, feeder_class) feedertab = SLIST_HEAD_INITIALIZER(feedertab);

void
feeder_register(void *p)
{
        struct feeder_class *fc = p;

        SLIST_INSERT_HEAD(&feedertab, fc, link);
}

static void
feeder_unregisterall(void *p __unused)
{
        SLIST_INIT(&feedertab);
}

static void
feeder_destroy(struct pcm_feeder *f)
{
        FEEDER_FREE(f);
        kobj_delete((kobj_t)f, M_FEEDER);
}

static struct pcm_feeder *
feeder_create(struct feeder_class *fc, struct pcm_feederdesc *desc)
{
        struct pcm_feeder *f;
        int err;

        f = (struct pcm_feeder *)kobj_create((kobj_class_t)fc, M_FEEDER, M_NOWAIT | M_ZERO);
        if (f == NULL)
                return NULL;

        f->class = fc;
        if (desc != NULL)
                f->desc = *desc;

        err = FEEDER_INIT(f);
        if (err) {
                printf("feeder_init(%p) on %s returned %d\n", f, fc->name, err);
                feeder_destroy(f);

                return NULL;
        }

        return f;
}

struct feeder_class *
feeder_getclass(u_int32_t type)
{
        struct feeder_class *fc;

        SLIST_FOREACH(fc, &feedertab, link) {
                if (fc->type == type)
                        return (fc);
        }
        return (NULL);
}

int
feeder_add(struct pcm_channel *c, struct feeder_class *fc, struct pcm_feederdesc *desc)
{
        struct pcm_feeder *nf;

        nf = feeder_create(fc, desc);
        if (nf == NULL)
                return ENOSPC;

        nf->source = c->feeder;

        if (c->feeder != NULL)
                c->feeder->parent = nf;
        c->feeder = nf;

        return 0;
}

void
feeder_remove(struct pcm_channel *c)
{
        struct pcm_feeder *f;

        while (c->feeder != NULL) {
                f = c->feeder;
                c->feeder = c->feeder->source;
                feeder_destroy(f);
        }
}

struct pcm_feeder *
feeder_find(struct pcm_channel *c, u_int32_t type)
{
        struct pcm_feeder *f;

        f = c->feeder;
        while (f != NULL) {
                if (f->class->type == type)
                        return f;
                f = f->source;
        }

        return NULL;
}

/*
 * 14bit format scoring
 * --------------------
 *
 *  13  12  11  10   9   8        2        1   0    offset
 * +---+---+---+---+---+---+-------------+---+---+
 * | X | X | X | X | X | X | X X X X X X | X | X |
 * +---+---+---+---+---+---+-------------+---+---+
 *   |   |   |   |   |   |        |        |   |
 *   |   |   |   |   |   |        |        |   +--> signed?
 *   |   |   |   |   |   |        |        |
 *   |   |   |   |   |   |        |        +------> bigendian?
 *   |   |   |   |   |   |        |
 *   |   |   |   |   |   |        +---------------> total channels
 *   |   |   |   |   |   |
 *   |   |   |   |   |   +------------------------> AFMT_A_LAW
 *   |   |   |   |   |
 *   |   |   |   |   +----------------------------> AFMT_MU_LAW
 *   |   |   |   |
 *   |   |   |   +--------------------------------> AFMT_8BIT
 *   |   |   |
 *   |   |   +------------------------------------> AFMT_16BIT
 *   |   |
 *   |   +----------------------------------------> AFMT_24BIT
 *   |
 *   +--------------------------------------------> AFMT_32BIT
 */
#define score_signeq(s1, s2)    (((s1) & 0x1) == ((s2) & 0x1))
#define score_endianeq(s1, s2)  (((s1) & 0x2) == ((s2) & 0x2))
#define score_cheq(s1, s2)      (((s1) & 0xfc) == ((s2) & 0xfc))
#define score_chgt(s1, s2)      (((s1) & 0xfc) > ((s2) & 0xfc))
#define score_chlt(s1, s2)      (((s1) & 0xfc) < ((s2) & 0xfc))
#define score_val(s1)           ((s1) & 0x3f00)
#define score_cse(s1)           ((s1) & 0x7f)

static u_int32_t
snd_fmtscore(u_int32_t fmt)
{
        u_int32_t ret;

        ret = 0;
        if (fmt & AFMT_SIGNED)
                ret |= 1 << 0;
        if (fmt & AFMT_BIGENDIAN)
                ret |= 1 << 1;
        /*if (fmt & AFMT_STEREO)
                ret |= (2 & 0x3f) << 2;
        else
                ret |= (1 & 0x3f) << 2;*/
        ret |= (AFMT_CHANNEL(fmt) & 0x3f) << 2;
        if (fmt & AFMT_A_LAW)
                ret |= 1 << 8;
        else if (fmt & AFMT_MU_LAW)
                ret |= 1 << 9;
        else if (fmt & AFMT_8BIT)
                ret |= 1 << 10;
        else if (fmt & AFMT_16BIT)
                ret |= 1 << 11;
        else if (fmt & AFMT_24BIT)
                ret |= 1 << 12;
        else if (fmt & AFMT_32BIT)
                ret |= 1 << 13;

        return ret;
}

static u_int32_t
snd_fmtbestfunc(u_int32_t fmt, u_int32_t *fmts, int cheq)
{
        u_int32_t best, score, score2, oldscore;
        int i;

        if (fmt == 0 || fmts == NULL || fmts[0] == 0)
                return 0;

        if (snd_fmtvalid(fmt, fmts))
                return fmt;

        best = 0;
        score = snd_fmtscore(fmt);
        oldscore = 0;
        for (i = 0; fmts[i] != 0; i++) {
                score2 = snd_fmtscore(fmts[i]);
                if (cheq && !score_cheq(score, score2) &&
                    (score_chlt(score2, score) ||
                    (oldscore != 0 && score_chgt(score2, oldscore))))
                                continue;
                if (oldscore == 0 ||
                            (score_val(score2) == score_val(score)) ||
                            (score_val(score2) == score_val(oldscore)) ||
                            (score_val(score2) > score_val(oldscore) &&
                            score_val(score2) < score_val(score)) ||
                            (score_val(score2) < score_val(oldscore) &&
                            score_val(score2) > score_val(score)) ||
                            (score_val(oldscore) < score_val(score) &&
                            score_val(score2) > score_val(oldscore))) {
                        if (score_val(oldscore) != score_val(score2) ||
                                    score_cse(score) == score_cse(score2) ||
                                    ((score_cse(oldscore) != score_cse(score) &&
                                    !score_endianeq(score, oldscore) &&
                                    (score_endianeq(score, score2) ||
                                    (!score_signeq(score, oldscore) &&
                                    score_signeq(score, score2)))))) {
                                best = fmts[i];
                                oldscore = score2;
                        }
                }
        }
        return best;
}

static u_int32_t
snd_fmtbestbit(u_int32_t fmt, u_int32_t *fmts)
{
        return snd_fmtbestfunc(fmt, fmts, 0);
}

static u_int32_t
snd_fmtbestchannel(u_int32_t fmt, u_int32_t *fmts)
{
        return snd_fmtbestfunc(fmt, fmts, 1);
}

u_int32_t
snd_fmtbest(u_int32_t fmt, u_int32_t *fmts)
{
        u_int32_t best1, best2;
        u_int32_t score, score1, score2;

        if (snd_fmtvalid(fmt, fmts))
                return fmt;

        best1 = snd_fmtbestchannel(fmt, fmts);
        best2 = snd_fmtbestbit(fmt, fmts);

        if (best1 != 0 && best2 != 0 && best1 != best2) {
                /*if (fmt & AFMT_STEREO)*/
                if (AFMT_CHANNEL(fmt) > 1)
                        return best1;
                else {
                        score = score_val(snd_fmtscore(fmt));
                        score1 = score_val(snd_fmtscore(best1));
                        score2 = score_val(snd_fmtscore(best2));
                        if (score1 == score2 || score1 == score)
                                return best1;
                        else if (score2 == score)
                                return best2;
                        else if (score1 > score2)
                                return best1;
                        return best2;
                }
        } else if (best2 == 0)
                return best1;
        else
                return best2;
}

static int
feed_root(struct pcm_feeder *feeder, struct pcm_channel *ch, u_int8_t *buffer, u_int32_t count, void *source)
{
        struct snd_dbuf *src = source;
        int l, offset;

        KASSERT(count > 0, ("feed_root: count == 0"));

        if (++ch->feedcount == 0)
                ch->feedcount = 2;

        l = min(count, sndbuf_getready(src));

        /* When recording only return as much data as available */
        if (ch->direction == PCMDIR_REC) {
                sndbuf_dispose(src, buffer, l);
                return l;
        }

        offset = count - l;

        if (offset > 0) {
                if (snd_verbose > 3)
                        printf("%s: (%s) %spending %d bytes "
                            "(count=%d l=%d feed=%d)\n",
                            __func__,
                            (ch->flags & CHN_F_VIRTUAL) ? "virtual" : "hardware",
                            (ch->feedcount == 1) ? "pre" : "ap",
                            offset, count, l, ch->feedcount);

                if (ch->feedcount == 1) {
                        memset(buffer, sndbuf_zerodata(src->fmt), offset);
                        if (l > 0)
                                sndbuf_dispose(src, buffer + offset, l);
                        else
                                ch->feedcount--;
                } else {
                        if (l > 0)
                                sndbuf_dispose(src, buffer, l);
                        memset(buffer + l, sndbuf_zerodata(src->fmt), offset);
                        if (!(ch->flags & CHN_F_CLOSING))
                                ch->xruns++;
                }
        } else if (l > 0)
                sndbuf_dispose(src, buffer, l);

        return count;
}

static kobj_method_t feeder_root_methods[] = {
        KOBJMETHOD(feeder_feed,         feed_root),
        KOBJMETHOD_END
};
static struct feeder_class feeder_root_class = {
        .name =         "feeder_root",
        .methods =      feeder_root_methods,
        .size =         sizeof(struct pcm_feeder),
        .type =         FEEDER_ROOT,
};
/*
 * Register the root feeder first so that pcm_addchan() and subsequent
 * functions can use it.
 */
SYSINIT(feeder_root, SI_SUB_DRIVERS, SI_ORDER_FIRST, feeder_register,
    &feeder_root_class);
SYSUNINIT(feeder_root, SI_SUB_DRIVERS, SI_ORDER_FIRST, feeder_unregisterall, NULL);