/*
    This file is part of jellything (https://codeberg.org/metamuffin/jellything)
    which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
    Copyright (C) 2026 metamuffin <metamuffin.org>
*/
/// <reference lib="dom" />

import { FormatInfo, StreamContainer } from "./types_stream.ts";

const cache = new Map<string, CodecSupport>()

export type CodecSupport = "unsupported" | "supported" | "supported_smooth"

export async function test_media_capability(format: FormatInfo, container: StreamContainer): Promise<CodecSupport> {
    const cache_key = JSON.stringify(format) + container
    const cached = cache.get(cache_key);
    if (cached !== undefined) return cached
    const r = await test_media_capability_inner(format, container)
    console.log(`media caps: codec=${format.codec} sup=${r}`);
    cache.set(cache_key, r)
    return r
}
async function test_media_capability_inner(format: FormatInfo, container: StreamContainer): Promise<CodecSupport> {
    if (format.codec == "S_TEXT/WEBVTT" || format.codec == "S_TEXT/UTF8" || format.codec == "D_WEBVTT/SUBTITLES") {
        return "supported"
    }
    let res;
    if (format.codec.startsWith("A_")) {
        res = await navigator.mediaCapabilities.decodingInfo({
            type: "media-source",
            audio: {
                contentType: track_to_content_type(format, container),
                samplerate: format.samplerate,
                channels: "" + format.channels,
                bitrate: format.bitrate,
            }
        })
    } else if (format.codec.startsWith("V_")) {
        res = await navigator.mediaCapabilities.decodingInfo({
            type: "media-source",
            video: {
                contentType: track_to_content_type(format, container),
                framerate: format.samplerate ?? 60,
                width: format.width ?? 1920,
                height: format.height ?? 1080,
                bitrate: format.bitrate
            }
        })
    } else {
        res = { supported: false, smooth: false }
    }
    return res.supported ? (res.smooth ? "supported_smooth" : "supported") : "unsupported"
}

export function track_to_content_type(format: FormatInfo, container: StreamContainer): string {
    let c = CONTAINER_TO_MIME_TYPE[container];
    if (format.codec.startsWith("A_")) c = c.replace("video/", "audio/")
    return `${c}; codecs="${format.codec_param}"`
}

const CONTAINER_TO_MIME_TYPE: { [key in StreamContainer]: string } = {
    webvtt: "text/webvtt",
    webm: "video/webm",
    matroska: "video/x-matroska",
    mpeg4: "video/mp4",
    jvtt: "application/jellything-vtt+json"
}