添加M3U8内容修改功能

[refgd]

功能范围

插件能力, 播放器

功能描述

如题, 以下是代码参考

fun getMediaSourceFactory(playerInfo: PlayerInfo): MediaSource.Factory {
    val httpDataSourceFactory = DefaultHttpDataSource.Factory()
        .setDefaultRequestProperties(playerInfo.header ?: emptyMap())
    val dataSourceFactory = DefaultDataSource.Factory(APP, httpDataSourceFactory)
    val streamDataSinkFactory = CacheDataSink.Factory().setCache(normalCache)
    val normalCacheDataSourceFactory = CacheDataSource.Factory()
        .setCache(normalCache)
        .setUpstreamDataSourceFactory(dataSourceFactory)
        .setCacheWriteDataSinkFactory(streamDataSinkFactory)
        .setFlags(CacheDataSource.FLAG_IGNORE_CACHE_ON_ERROR)

    return when (playerInfo.decodeType) {
        C.CONTENT_TYPE_DASH -> DashMediaSource.Factory(normalCacheDataSourceFactory)
        C.CONTENT_TYPE_HLS -> {
            // Use custom DataSource.Factory to modify M3U8 content
            val customHlsDataSourceFactory = CustomDataSourceFactory(
                normalCacheDataSourceFactory, playerInfo.replaces
            )
            HlsMediaSource.Factory(customHlsDataSourceFactory)
        }
        else -> ProgressiveMediaSource.Factory(normalCacheDataSourceFactory)
    }
}

// Custom DataSource.Factory that modifies M3U8 content
class CustomDataSourceFactory(
    private val upstreamFactory: DataSource.Factory,
    private val replaces: List>
) : DataSource.Factory {

    override fun createDataSource(): DataSource {
        return object : DataSource {
            private var upstream: DataSource = upstreamFactory.createDataSource()

            override fun open(dataSpec: DataSpec): Long {
                return upstream.open(dataSpec)
            }

            override fun read(buffer: ByteArray, offset: Int, readLength: Int): Int {
                val result = upstream.read(buffer, offset, readLength)
                if (result == C.RESULT_END_OF_INPUT) {
                    val m3u8Content = String(buffer, StandardCharsets.UTF_8)
                    val modifiedM3u8Content = modifyM3u8Content(m3u8Content, replaces)
                    val byteArrayInputStream: InputStream = ByteArrayInputStream(
                        modifiedM3u8Content.toByteArray(StandardCharsets.UTF_8)
                    )
                    return byteArrayInputStream.read(buffer, offset, readLength)
                }
                return result
            }

            override fun getUri(): Uri? = upstream.uri

            override fun close() {
                upstream.close()
            }
        }
    }

    // Function to modify M3U8 content using the list of regex replacements
    private fun modifyM3u8Content(content: String, replaces: List>): String {
        var modifiedContent = content
        for ((regex, replacement) in replaces) {
            modifiedContent = regex.replace(modifiedContent, replacement)
        }
        return modifiedContent
    }
}