/*
 * This file is part of mplayer.
 *
 * mplayer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * mplayer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with mplayer.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <assert.h>

#include "config.h"
#include "core/mp_msg.h"

#include "video/img_format.h"
#include "video/mp_image.h"
#include "vf.h"

#include "core/m_option.h"
#include "core/m_struct.h"

#include "vf_dlopen.h"

#ifdef _WIN32
# include <windows.h>
# define DLLOpen(name)           LoadLibrary(name)
# define DLLClose(handle)        FreeLibrary(handle)
# define DLLSymbol(handle, name) ((void *)GetProcAddress(handle, name))
#else
# include <dlfcn.h>
# define DLLOpen(name)           dlopen(name, RTLD_NOW)
# define DLLClose(handle)        dlclose(handle)
# define DLLSymbol(handle, name) dlsym(handle, name)
#endif

static struct vf_priv_s {
    const char *cfg_dllname;
    int cfg_argc;
    const char *cfg_argv[4];
    void *dll;
    struct vf_dlopen_context filter;

    // output mp_image_t stuff
    mp_image_t *outpic[FILTER_MAX_OUTCNT];

    // generic
    unsigned int out_cnt, out_width, out_height;

    // multi frame output
    unsigned int outbufferpos;
    unsigned int outbufferlen;
    mp_image_t *outbuffermpi;

    // qscale buffer
    unsigned char *qbuffer;
    size_t qbuffersize;

    unsigned int outfmt;

    int argc;
} const vf_priv_dflt = {};

struct fmtname {
    const char *name;
    enum mp_imgfmt fmt;
};

// This table defines the pixel format names that are guaranteed to work.
static const struct fmtname format_names[] = {
    {"yv12", IMGFMT_420P},
    {0}
};

//===========================================================================//

static const char *imgfmt_to_name(int fmt)
{
    for (int n = 0; format_names[n].name; n++) {
        if (format_names[n].fmt == fmt)
            return format_names[n].name;
    }
    return mp_imgfmt_to_name(fmt);
}

static int name_to_imgfmt(const char *name)
{
    for (int n = 0; format_names[n].name; n++) {
        if (strcasecmp(format_names[n].name, name) == 0)
            return format_names[n].fmt;
    }
    return mp_imgfmt_from_name(bstr0(name), false);
}

static void set_imgprop(struct vf_dlopen_picdata *out, const mp_image_t *mpi)
{
    int i;
    out->planes = mpi->num_planes;
    for (i = 0; i < mpi->num_planes; ++i) {
        out->plane[i] = mpi->planes[i];
        out->planestride[i] = mpi->stride[i];
        out->planewidth[i] =
            i ? (/*mpi->chroma_width*/ mpi->w >> mpi->chroma_x_shift) : mpi->w;
        out->planeheight[i] =
            i ? (/*mpi->chroma_height*/ mpi->h >> mpi->chroma_y_shift) : mpi->h;
        out->planexshift[i] = i ? mpi->chroma_x_shift : 0;
        out->planeyshift[i] = i ? mpi->chroma_y_shift : 0;
    }
}

static int config(struct vf_instance *vf,
                  int width, int height, int d_width, int d_height,
                  unsigned int flags, unsigned int fmt)
{
    vf->priv->filter.in_width = width;
    vf->priv->filter.in_height = height;
    vf->priv->filter.in_d_width = d_width;
    vf->priv->filter.in_d_height = d_height;
    vf->priv->filter.in_fmt = imgfmt_to_name(fmt);
    vf->priv->filter.out_width = width;
    vf->priv->filter.out_height = height;
    vf->priv->filter.out_d_width = d_width;
    vf->priv->filter.out_d_height = d_height;
    vf->priv->filter.out_fmt = NULL;
    vf->priv->filter.out_cnt = 1;

    if (!vf->priv->filter.in_fmt) {
        mp_msg(MSGT_VFILTER, MSGL_ERR, "invalid input/output format\n");
        return 0;
    }
    if (vf->priv->filter.config && vf->priv->filter.config(&vf->priv->filter) < 0) {
        mp_msg(MSGT_VFILTER, MSGL_ERR, "filter config failed\n");
        return 0;
    }

    // copy away stuff to sanity island
    vf->priv->out_cnt = vf->priv->filter.out_cnt;
    vf->priv->out_width = vf->priv->filter.out_width;
    vf->priv->out_height = vf->priv->filter.out_height;

    if (vf->priv->filter.out_fmt)
        vf->priv->outfmt = name_to_imgfmt(vf->priv->filter.out_fmt);
    else {
        struct vf_dlopen_formatpair *p = vf->priv->filter.format_mapping;
        vf->priv->outfmt = 0;
        if (p) {
            for (; p->from; ++p) {
                // TODO support pixel format classes in matching
                if (!strcmp(p->from, vf->priv->filter.in_fmt)) {
                    vf->priv->outfmt = name_to_imgfmt(p->to);
                    break;
                }
            }
        } else
            vf->priv->outfmt = fmt;
        vf->priv->filter.out_fmt = imgfmt_to_name(vf->priv->outfmt);
    }

    if (!vf->priv->outfmt) {
        mp_msg(MSGT_VFILTER, MSGL_ERR,
               "filter config wants an unsupported output format\n");
        return 0;
    }
    if (!vf->priv->out_cnt || vf->priv->out_cnt > FILTER_MAX_OUTCNT) {
        mp_msg(MSGT_VFILTER, MSGL_ERR,
               "filter config wants to yield zero or too many output frames\n");
        return 0;
    }

    for (int i = 0; i < vf->priv->out_cnt; ++i) {
        talloc_free(vf->priv->outpic[i]);
        vf->priv->outpic[i] =
            mp_image_alloc(vf->priv->out_width, vf->priv->out_height,
                           vf->priv->outfmt);
        set_imgprop(&vf->priv->filter.outpic[i], vf->priv->outpic[i]);
        talloc_steal(vf, vf->priv->outpic[i]);
    }

    return vf_next_config(vf, vf->priv->out_width,
                          vf->priv->out_height,
                          vf->priv->filter.out_d_width,
                          vf->priv->filter.out_d_height,
                          flags, vf->priv->outfmt);
}

static void uninit(struct vf_instance *vf)
{
    if (vf->priv->filter.uninit)
        vf->priv->filter.uninit(&vf->priv->filter);
    memset(&vf->priv->filter, 0, sizeof(vf->priv->filter));
    if (vf->priv->dll) {
        DLLClose(vf->priv->dll);
        vf->priv->dll = NULL;
    }
    if (vf->priv->qbuffer) {
        free(vf->priv->qbuffer);
        vf->priv->qbuffer = NULL;
    }
}

static int filter(struct vf_instance *vf, struct mp_image *mpi)
{
    int i, k;

    set_imgprop(&vf->priv->filter.inpic, mpi);
    if (mpi->qscale) {
        if (mpi->qscale_type != 0) {
            k = mpi->qstride * ((mpi->h + 15) >> 4);
            if (vf->priv->qbuffersize != k) {
                vf->priv->qbuffer = realloc(vf->priv->qbuffer, k);
                vf->priv->qbuffersize = k;
            }
            for (i = 0; i < k; ++i)
                vf->priv->qbuffer[i] = norm_qscale(mpi->qscale[i],
                                                   mpi->qscale_type);
            vf->priv->filter.inpic_qscale = vf->priv->qbuffer;
        } else
            vf->priv->filter.inpic_qscale = mpi->qscale;
        vf->priv->filter.inpic_qscalestride = mpi->qstride;
        vf->priv->filter.inpic_qscaleshift = 4;
    } else {
        vf->priv->filter.inpic_qscale = NULL;
        vf->priv->filter.inpic_qscalestride = 0;
        vf->priv->filter.inpic_qscaleshift = 0;
    }
    vf->priv->filter.inpic.pts = mpi->pts;

    struct mp_image *out[FILTER_MAX_OUTCNT] = {0};

    for (int n = 0; n < vf->priv->out_cnt; n++) {
        out[n] = vf_alloc_out_image(vf);
        mp_image_copy_attributes(out[n], mpi);
        set_imgprop(&vf->priv->filter.outpic[n], out[n]);
    }

    // more than one out pic
    int ret = vf->priv->filter.put_image(&vf->priv->filter);
    if (ret < 0)
        ret = 0;
    assert(ret <= vf->priv->out_cnt);

    for (int n = 0; n < ret; n++) {
        out[n]->pts = vf->priv->filter.outpic[n].pts;
        vf_add_output_frame(vf, out[n]);
    }
    for (int n = ret; n < FILTER_MAX_OUTCNT; n++) {
        talloc_free(out[n]);
    }

    talloc_free(mpi);
    return 0;
}

//===========================================================================//

static int query_format(struct vf_instance *vf, unsigned int fmt)
{
    if (IMGFMT_IS_HWACCEL(fmt))
        return 0;  // these can't really be filtered
    if (fmt == IMGFMT_PAL8)
        return 0;  // we don't have palette support, sorry
    const char *fmtname = imgfmt_to_name(fmt);
    if (!fmtname)
        return 0;
    struct vf_dlopen_formatpair *p = vf->priv->filter.format_mapping;
    unsigned int outfmt = 0;
    if (p) {
        for (; p->from; ++p) {
            // TODO support pixel format classes in matching
            if (!strcmp(p->from, fmtname)) {
                outfmt = name_to_imgfmt(p->to);
                break;
            }
        }
    } else
        outfmt = fmt;
    if (!outfmt)
        return 0;
    return vf_next_query_format(vf, outfmt);
}

static int vf_open(vf_instance_t *vf, char *args)
{
    if (!vf->priv->cfg_dllname) {
        mp_msg(MSGT_VFILTER, MSGL_ERR,
               "usage: -vf dlopen=filename.so:function:args\n");
        return 0;
    }

    vf->priv->dll = DLLOpen(vf->priv->cfg_dllname);
    if (!vf->priv->dll) {
        mp_msg(MSGT_VFILTER, MSGL_ERR, "library not found: %s\n",
               vf->priv->cfg_dllname);
        return 0;
    }

    vf_dlopen_getcontext_func *func =
        (vf_dlopen_getcontext_func *) DLLSymbol(vf->priv->dll, "vf_dlopen_getcontext");
    if (!func) {
        mp_msg(MSGT_VFILTER, MSGL_ERR, "library is not a filter: %s\n",
               vf->priv->cfg_dllname);
        return 0;
    }

    memset(&vf->priv->filter, 0, sizeof(vf->priv->filter));
    vf->priv->filter.major_version = VF_DLOPEN_MAJOR_VERSION;
    vf->priv->filter.minor_version = VF_DLOPEN_MINOR_VERSION;

    // count arguments
    for (vf->priv->cfg_argc = 0;
         vf->priv->cfg_argc < sizeof(vf->priv->cfg_argv) / sizeof(vf->priv->cfg_argv[0]) && vf->priv->cfg_argv[vf->priv->cfg_argc];
         ++vf->priv->cfg_argc)
        ;

    if (func(&vf->priv->filter, vf->priv->cfg_argc, vf->priv->cfg_argv) < 0) {
        mp_msg(MSGT_VFILTER, MSGL_ERR,
               "function did not create a filter: %s\n",
               vf->priv->cfg_dllname);
        return 0;
    }

    if (!vf->priv->filter.put_image) {
        mp_msg(MSGT_VFILTER, MSGL_ERR,
               "function did not create a filter that can put images: %s\n",
               vf->priv->cfg_dllname);
        return 0;
    }

    vf->filter_ext = filter;
    vf->query_format = query_format;
    vf->config = config;
    vf->uninit = uninit;

    return 1;
}

#define ST_OFF(f) M_ST_OFF(struct vf_priv_s, f)
static m_option_t vf_opts_fields[] = {
    {"dll", ST_OFF(cfg_dllname), CONF_TYPE_STRING, 0, 0, 0, NULL},
    {"a0", ST_OFF(cfg_argv[0]), CONF_TYPE_STRING, 0, 0, 0, NULL},
    {"a1", ST_OFF(cfg_argv[1]), CONF_TYPE_STRING, 0, 0, 0, NULL},
    {"a2", ST_OFF(cfg_argv[2]), CONF_TYPE_STRING, 0, 0, 0, NULL},
    {"a3", ST_OFF(cfg_argv[3]), CONF_TYPE_STRING, 0, 0, 0, NULL},
    { NULL, NULL, 0, 0, 0, 0, NULL }
};

static const m_struct_t vf_opts = {
    "dlopen",
    sizeof(struct vf_priv_s),
    &vf_priv_dflt,
    vf_opts_fields
};

const vf_info_t vf_info_dlopen = {
    "Dynamic library filter",
    "dlopen",
    "Rudolf Polzer",
    "",
    vf_open,
    &vf_opts
};

//===========================================================================//