conventionschedule-android/app/src/main/java/com/adlerosn/brasilfurfest/schedule/managers/OfflineCacheManager.kt

package com.adlerosn.brasilfurfest.schedule.managers

import android.content.Context
import android.content.res.Resources
import com.adlerosn.brasilfurfest.helper.joinFile
import com.adlerosn.brasilfurfest.helper.lastPathPart
import com.adlerosn.brasilfurfest.helper.nullFun
import java.io.File
import java.io.InputStream
import java.lang.Exception

class OfflineCacheManager(context: Context): CacheManager() {
    private val assets = context.assets
    private val cacheDir = context.cacheDir
    override val goesOnline = false
    override val preloaded = false
    override fun getStamp(file: String): String? = get(file)?.second
    override fun get(file: String): Pair<InputStream, String>? = try {
        Pair(assets.open("out/$file"), UNIX_TIMESTAMP_START)
    } catch (e: Exception) { null }
    override fun set(file: String, requestResult: Pair<ByteArray, String>) = nullFun()
    override fun delete(file: String) = false
    override fun sanitize() = 0
    override fun startMonitoringNeededFiles() = nullFun()
    override fun removeNotNeededFiles() = 0
    override val files get() = (assets.list("out") ?: arrayOf()).toSet()
    override fun getFileFor(asset: String): File {
        val cachedFile = cacheDir.joinFile(asset.lastPathPart())
        if(!cachedFile.exists()){
            val assetDescriptor = get(asset.lastPathPart())
            if (assetDescriptor == null)
                throw Resources.NotFoundException("Unavailable asset: $asset")
            else
                cachedFile.writeBytes(assetDescriptor.first.readBytes())
        }
        return cachedFile
    }
}