/*
 * Copyright (c) Lynne
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/opt.h"
#include "vulkan_filter.h"
#include "scale_eval.h"
#include "filters.h"
#include "colorspace.h"
#include "video.h"
#include "libswscale/swscale.h"

extern const unsigned char ff_scale_comp_spv_data[];
extern const unsigned int ff_scale_comp_spv_len;

extern const unsigned char ff_debayer_comp_spv_data[];
extern const unsigned int ff_debayer_comp_spv_len;

enum ScalerFunc {
    F_BILINEAR = 0,
    F_NEAREST,

    F_NB,
};

enum DebayerFunc {
    DB_BILINEAR = 0,
    DB_BILINEAR_HQ,

    DB_NB,
};

/* Output modes, must match scale.comp.glsl */
enum ScaleMode {
    MODE_COPY = 0,
    MODE_NV12,
    MODE_YUV420,
    MODE_YUV444,
};

typedef struct ScaleVulkanContext {
    FFVulkanContext vkctx;
    SwsContext *sws;

    int initialized;
    FFVkExecPool e;
    AVVulkanDeviceQueueFamily *qf;
    FFVulkanShader shd;
    VkSampler sampler;

    /* Push constants / options */
    struct {
        float yuv_matrix[4][4];
        int crop_x;
        int crop_y;
        int crop_w;
        int crop_h;
        float in_dims[2];
    } opts;

    char *out_format_string;
    char *w_expr;
    char *h_expr;

    enum ScalerFunc scaler;
    enum AVColorRange out_range;
    enum DebayerFunc debayer;
} ScaleVulkanContext;

static av_cold int init_filter(AVFilterContext *ctx, AVFrame *in)
{
    int err;
    VkFilter sampler_mode;
    enum ScaleMode mode;
    ScaleVulkanContext *s = ctx->priv;
    FFVulkanContext *vkctx = &s->vkctx;
    FFVulkanShader *shd = &s->shd;

    int in_planes = av_pix_fmt_count_planes(s->vkctx.input_format);
    int out_planes = av_pix_fmt_count_planes(s->vkctx.output_format);

    switch (s->scaler) {
    case F_NEAREST:
        sampler_mode = VK_FILTER_NEAREST;
        break;
    case F_BILINEAR:
        sampler_mode = VK_FILTER_LINEAR;
        break;
    };

    if (s->vkctx.output_format == s->vkctx.input_format) {
        mode = MODE_COPY;
    } else {
        switch (s->vkctx.output_format) {
        case AV_PIX_FMT_NV12:    mode = MODE_NV12;   break;
        case AV_PIX_FMT_YUV420P: mode = MODE_YUV420; break;
        case AV_PIX_FMT_YUV444P: mode = MODE_YUV444; break;
        default: return AVERROR(EINVAL);
        }
    }

    RET(ff_vk_exec_pool_init(vkctx, s->qf, &s->e, FF_VK_DEFAULT_EXEC_CONTEXTS, 0, 0, 0, NULL));

    RET(ff_vk_init_sampler(vkctx, &s->sampler, 0, sampler_mode));

    SPEC_LIST_CREATE(sl, 3, 3*sizeof(int32_t))
    SPEC_LIST_ADD(sl, 0, 32, out_planes);
    SPEC_LIST_ADD(sl, 1, 32, mode);
    SPEC_LIST_ADD(sl, 2, 32, s->out_range == AVCOL_RANGE_JPEG);

    ff_vk_shader_load(&s->shd, VK_SHADER_STAGE_COMPUTE_BIT, sl,
                      (uint32_t []) { 32, 32, 1 }, 0);

    const FFVulkanDescriptorSetBinding desc[] = {
        {
            .name       = "input_img",
            .type       = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
            .elems      = in_planes,
            .stages     = VK_SHADER_STAGE_COMPUTE_BIT,
            .samplers   = DUP_SAMPLER(s->sampler),
        },
        {
            .name       = "output_img",
            .type       = VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
            .elems      = out_planes,
            .stages     = VK_SHADER_STAGE_COMPUTE_BIT,
        },
    };

    ff_vk_shader_add_descriptor_set(vkctx, &s->shd, desc, 2, 0);

    ff_vk_shader_add_push_const(&s->shd, 0, sizeof(s->opts),
                                VK_SHADER_STAGE_COMPUTE_BIT);

    if (mode != MODE_COPY) {
        const AVLumaCoefficients *lcoeffs;
        double tmp_mat[3][3];

        lcoeffs = av_csp_luma_coeffs_from_avcsp(in->colorspace);
        if (!lcoeffs) {
            av_log(ctx, AV_LOG_ERROR, "Unsupported colorspace\n");
            err = AVERROR(EINVAL);
            goto fail;
        }

        ff_fill_rgb2yuv_table(lcoeffs, tmp_mat);

        for (int y = 0; y < 3; y++)
            for (int x = 0; x < 3; x++)
                s->opts.yuv_matrix[x][y] = tmp_mat[x][y];
        s->opts.yuv_matrix[3][3] = 1.0;
    }

    s->opts.in_dims[0] = in->width;
    s->opts.in_dims[1] = in->height;

    RET(ff_vk_shader_link(vkctx, shd,
                          ff_scale_comp_spv_data,
                          ff_scale_comp_spv_len, "main"));

    RET(ff_vk_shader_register_exec(vkctx, &s->e, &s->shd));

    s->initialized = 1;

fail:
    return err;
}

static av_cold int init_debayer(AVFilterContext *ctx, AVFrame *in)
{
    int err;
    ScaleVulkanContext *s = ctx->priv;
    FFVulkanContext *vkctx = &s->vkctx;
    FFVulkanShader *shd = &s->shd;

    RET(ff_vk_exec_pool_init(vkctx, s->qf, &s->e, FF_VK_DEFAULT_EXEC_CONTEXTS, 0, 0, 0, NULL));

    SPEC_LIST_CREATE(sl, 1, 1*sizeof(int32_t))
    SPEC_LIST_ADD(sl, 0, 32, s->debayer);
    ff_vk_shader_load(&s->shd, VK_SHADER_STAGE_COMPUTE_BIT, sl,
                      (uint32_t []) { 32, 32, 1 }, 0);

    ff_vk_shader_add_push_const(&s->shd, 0, sizeof(s->opts),
                                VK_SHADER_STAGE_COMPUTE_BIT);

    const FFVulkanDescriptorSetBinding desc[] = {
        {
            .name       = "src",
            .type       = VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
            .stages     = VK_SHADER_STAGE_COMPUTE_BIT,
        },
        {
            .name       = "dst",
            .type       = VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
            .stages     = VK_SHADER_STAGE_COMPUTE_BIT,
        },
    };
    ff_vk_shader_add_descriptor_set(vkctx, &s->shd, desc, 2, 0);

    RET(ff_vk_shader_link(vkctx, shd,
                          ff_debayer_comp_spv_data,
                          ff_debayer_comp_spv_len, "main"));

    RET(ff_vk_shader_register_exec(vkctx, &s->e, &s->shd));

    shd->lg_size[0] <<= 1;
    shd->lg_size[1] <<= 1;

    s->initialized = 1;

fail:
    return err;
}

static int scale_vulkan_filter_frame(AVFilterLink *link, AVFrame *in)
{
    int err;
    AVFilterContext *ctx = link->dst;
    ScaleVulkanContext *s = ctx->priv;
    AVFilterLink *outlink = ctx->outputs[0];

    AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
    if (!out) {
        err = AVERROR(ENOMEM);
        goto fail;
    }

    s->opts.crop_x = in->crop_left;
    s->opts.crop_y = in->crop_top;
    s->opts.crop_w = in->width - (in->crop_left + in->crop_right);
    s->opts.crop_h = in->height - (in->crop_top + in->crop_bottom);

    err = av_frame_copy_props(out, in);
    if (err < 0)
        goto fail;

    if (out->width != in->width || out->height != in->height) {
        av_frame_side_data_remove_by_props(&out->side_data, &out->nb_side_data,
                                           AV_SIDE_DATA_PROP_SIZE_DEPENDENT);
    }

    if (s->out_range != AVCOL_RANGE_UNSPECIFIED)
        out->color_range = s->out_range;
    if (s->vkctx.output_format != s->vkctx.input_format)
        out->chroma_location = AVCHROMA_LOC_TOPLEFT;

    if (!s->sws) {
        if (!s->initialized) {
            s->qf = ff_vk_qf_find(&s->vkctx, VK_QUEUE_COMPUTE_BIT, 0);
            if (!s->qf) {
                av_log(ctx, AV_LOG_ERROR, "Device has no compute queues\n");
                err = AVERROR(ENOTSUP);
                goto fail;
            }

            if (s->vkctx.input_format == AV_PIX_FMT_BAYER_RGGB16)
                RET(init_debayer(ctx, in));
            else
                RET(init_filter(ctx, in));
        }

        RET(ff_vk_filter_process_simple(&s->vkctx, &s->e, &s->shd, out, in,
                                        s->sampler, 1, &s->opts, sizeof(s->opts)));
    } else {
        err = sws_scale_frame(s->sws, out, in);
        if (err < 0)
            goto fail;
    }

    av_frame_free(&in);

    return ff_filter_frame(outlink, out);

fail:
    av_frame_free(&in);
    av_frame_free(&out);
    return err;
}

static int scale_vulkan_config_output(AVFilterLink *outlink)
{
    int err;
    AVFilterContext *avctx = outlink->src;
    ScaleVulkanContext *s  = avctx->priv;
    FFVulkanContext *vkctx = &s->vkctx;
    AVFilterLink *inlink   = outlink->src->inputs[0];

    err = ff_scale_eval_dimensions(s, s->w_expr, s->h_expr, inlink, outlink,
                                   &vkctx->output_width,
                                   &vkctx->output_height);
    if (err < 0)
        return err;

    err = ff_scale_adjust_dimensions(inlink, &vkctx->output_width, &vkctx->output_height,
                                     SCALE_FORCE_OAR_DISABLE, 1, 1.f);
    if (err < 0)
        return err;

    outlink->w = vkctx->output_width;
    outlink->h = vkctx->output_height;

    if (s->out_format_string) {
        s->vkctx.output_format = av_get_pix_fmt(s->out_format_string);
        if (s->vkctx.output_format == AV_PIX_FMT_NONE) {
            av_log(avctx, AV_LOG_ERROR, "Invalid output format.\n");
            return AVERROR(EINVAL);
        }
    } else {
        s->vkctx.output_format = s->vkctx.input_format;
    }

    if (s->vkctx.input_format == AV_PIX_FMT_BAYER_RGGB16) {
        if (s->vkctx.output_format == s->vkctx.input_format) {
            s->vkctx.output_format = AV_PIX_FMT_RGBA64;
        } else if (!ff_vk_mt_is_np_rgb(s->vkctx.output_format)) {
            av_log(avctx, AV_LOG_ERROR, "Unsupported output format for debayer\n");
            return AVERROR(EINVAL);
        }
        if (inlink->w != outlink->w || inlink->w != outlink->w) {
            av_log(avctx, AV_LOG_ERROR, "Scaling is not supported with debayering\n");
            return AVERROR_PATCHWELCOME;
        }
    } else if ((inlink->w == outlink->w || inlink->h == outlink->h) &&
               (s->vkctx.input_format != s->vkctx.output_format)) {
        s->sws = sws_alloc_context();
        if (!s->sws)
            return AVERROR(ENOMEM);
        av_opt_set(s->sws, "sws_flags", "unstable", 0);
        av_opt_set(s->sws, "scaler",
                   s->scaler == F_NEAREST ? "point" : "bilinear", 0);
    } else if (s->vkctx.output_format != s->vkctx.input_format) {
        if (!ff_vk_mt_is_np_rgb(s->vkctx.input_format)) {
            av_log(avctx, AV_LOG_ERROR, "Unsupported input format for conversion\n");
            return AVERROR(EINVAL);
        }
        if (s->vkctx.output_format != AV_PIX_FMT_NV12 &&
            s->vkctx.output_format != AV_PIX_FMT_YUV420P &&
            s->vkctx.output_format != AV_PIX_FMT_YUV444P) {
            av_log(avctx, AV_LOG_ERROR, "Unsupported output format\n");
            return AVERROR(EINVAL);
        }
    } else if (s->out_range != AVCOL_RANGE_UNSPECIFIED) {
        av_log(avctx, AV_LOG_ERROR, "Cannot change range without converting format\n");
        return AVERROR(EINVAL);
    }

    return ff_vk_filter_config_output(outlink);
}

static void scale_vulkan_uninit(AVFilterContext *avctx)
{
    ScaleVulkanContext *s = avctx->priv;
    FFVulkanContext *vkctx = &s->vkctx;
    FFVulkanFunctions *vk = &vkctx->vkfn;

    ff_vk_exec_pool_free(vkctx, &s->e);
    ff_vk_shader_free(vkctx, &s->shd);
    sws_free_context(&s->sws);

    if (s->sampler)
        vk->DestroySampler(vkctx->hwctx->act_dev, s->sampler,
                           vkctx->hwctx->alloc);

    ff_vk_uninit(&s->vkctx);

    s->initialized = 0;
}

#define OFFSET(x) offsetof(ScaleVulkanContext, x)
#define FLAGS (AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
static const AVOption scale_vulkan_options[] = {
    { "w", "Output video width",  OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, .flags = FLAGS },
    { "h", "Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, .flags = FLAGS },
    { "scaler", "Scaler function", OFFSET(scaler), AV_OPT_TYPE_INT, {.i64 = F_BILINEAR}, 0, F_NB, .flags = FLAGS, .unit = "scaler" },
        { "bilinear", "Bilinear interpolation (fastest)", 0, AV_OPT_TYPE_CONST, {.i64 = F_BILINEAR}, 0, 0, .flags = FLAGS, .unit = "scaler" },
        { "nearest", "Nearest (useful for pixel art)", 0, AV_OPT_TYPE_CONST, {.i64 = F_NEAREST}, 0, 0, .flags = FLAGS, .unit = "scaler" },
    { "debayer", "Debayer algorithm to use", OFFSET(debayer), AV_OPT_TYPE_INT, {.i64 = DB_BILINEAR_HQ}, 0, DB_NB, .flags = FLAGS, .unit = "debayer" },
        { "bilinear", "Bilinear debayering (fastest)", 0, AV_OPT_TYPE_CONST, {.i64 = DB_BILINEAR}, 0, 0, .flags = FLAGS, .unit = "debayer" },
        { "bilinear_hq", "Bilinear debayering (high quality)", 0, AV_OPT_TYPE_CONST, {.i64 = DB_BILINEAR_HQ}, 0, 0, .flags = FLAGS, .unit = "debayer" },
    { "format", "Output video format (software format of hardware frames)", OFFSET(out_format_string), AV_OPT_TYPE_STRING, .flags = FLAGS },
    { "out_range", "Output colour range (from 0 to 2) (default 0)", OFFSET(out_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED}, AVCOL_RANGE_UNSPECIFIED, AVCOL_RANGE_JPEG, .flags = FLAGS, .unit = "range" },
        { "full", "Full range", 0, AV_OPT_TYPE_CONST, { .i64 = AVCOL_RANGE_JPEG }, 0, 0, FLAGS, .unit = "range" },
        { "limited", "Limited range", 0, AV_OPT_TYPE_CONST, { .i64 = AVCOL_RANGE_MPEG }, 0, 0, FLAGS, .unit = "range" },
        { "jpeg", "Full range", 0, AV_OPT_TYPE_CONST, { .i64 = AVCOL_RANGE_JPEG }, 0, 0, FLAGS, .unit = "range" },
        { "mpeg", "Limited range", 0, AV_OPT_TYPE_CONST, { .i64 = AVCOL_RANGE_MPEG }, 0, 0, FLAGS, .unit = "range" },
        { "tv", "Limited range", 0, AV_OPT_TYPE_CONST, { .i64 = AVCOL_RANGE_MPEG }, 0, 0, FLAGS, .unit = "range" },
        { "pc", "Full range", 0, AV_OPT_TYPE_CONST, { .i64 = AVCOL_RANGE_JPEG }, 0, 0, FLAGS, .unit = "range" },
    { NULL },
};

AVFILTER_DEFINE_CLASS(scale_vulkan);

static const AVFilterPad scale_vulkan_inputs[] = {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_VIDEO,
        .filter_frame = &scale_vulkan_filter_frame,
        .config_props = &ff_vk_filter_config_input,
    },
};

static const AVFilterPad scale_vulkan_outputs[] = {
    {
        .name = "default",
        .type = AVMEDIA_TYPE_VIDEO,
        .config_props = &scale_vulkan_config_output,
    },
};

const FFFilter ff_vf_scale_vulkan = {
    .p.name         = "scale_vulkan",
    .p.description  = NULL_IF_CONFIG_SMALL("Scale Vulkan frames"),
    .p.priv_class   = &scale_vulkan_class,
    .p.flags        = AVFILTER_FLAG_HWDEVICE,
    .priv_size      = sizeof(ScaleVulkanContext),
    .init           = &ff_vk_filter_init,
    .uninit         = &scale_vulkan_uninit,
    FILTER_INPUTS(scale_vulkan_inputs),
    FILTER_OUTPUTS(scale_vulkan_outputs),
    FILTER_SINGLE_PIXFMT(AV_PIX_FMT_VULKAN),
    .flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE,
};
