package com.rnwallpapers

import android.content.Context
import android.graphics.BitmapFactory
import android.os.Build
import androidx.work.*
import java.io.File
import java.net.HttpURLConnection
import java.net.URL
import java.util.concurrent.TimeUnit

class AutoChangeWorker(
    private val context: Context,
    workerParams: WorkerParameters
) : CoroutineWorker(context, workerParams) {

    override suspend fun doWork(): Result {
        return try {
            val prefs = context.getSharedPreferences("RNWallpapers", Context.MODE_PRIVATE)

            if (!prefs.getBoolean("auto_active", false)) {
                return Result.success()
            }

            val sources = prefs.getStringSet("auto_sources", emptySet())?.toList()
                ?: return Result.failure()

            if (sources.isEmpty()) return Result.failure()

            val shuffle = prefs.getBoolean("auto_shuffle", false)
            var index = prefs.getInt("auto_index", 0)
            val target = prefs.getString("auto_target", "home") ?: "home"

            // Pick next source
            val source = if (shuffle) {
                sources.random()
            } else {
                val current = sources[index % sources.size]
                index = (index + 1) % sources.size
                prefs.edit().putInt("auto_index", index).apply()
                current
            }

            // Download and set
            val bitmap = if (source.startsWith("http")) {
                val conn = URL(source).openConnection() as HttpURLConnection
                conn.connect()
                BitmapFactory.decodeStream(conn.inputStream)
            } else {
                BitmapFactory.decodeFile(source.removePrefix("file://"))
            } ?: return Result.retry()

            val wallpaperManager = android.app.WallpaperManager.getInstance(context)

            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                val flag = when (target) {
                    "home" -> android.app.WallpaperManager.FLAG_SYSTEM
                    "lock" -> android.app.WallpaperManager.FLAG_LOCK
                    else -> android.app.WallpaperManager.FLAG_SYSTEM or android.app.WallpaperManager.FLAG_LOCK
                }
                wallpaperManager.setBitmap(bitmap, null, true, flag)
            } else {
                wallpaperManager.setBitmap(bitmap)
            }

            // Save last set info
            prefs.edit().apply {
                putString("last_set_target", target)
                putString("last_set_type", "static")
                putString("last_set_path", source)
                putLong("last_set_at", System.currentTimeMillis())
                apply()
            }

            Result.success()
        } catch (e: Exception) {
            Result.retry()
        }
    }

    companion object {
        private const val WORK_TAG = "RNWallpapers_AutoChange"

        fun schedule(context: Context, intervalMinutes: Long) {
            val constraints = Constraints.Builder()
                .setRequiredNetworkType(NetworkType.CONNECTED)
                .build()

            val request = PeriodicWorkRequestBuilder<AutoChangeWorker>(
                intervalMinutes, TimeUnit.MINUTES
            )
                .setConstraints(constraints)
                .addTag(WORK_TAG)
                .setBackoffCriteria(BackoffPolicy.LINEAR, 15, TimeUnit.MINUTES)
                .build()

            WorkManager.getInstance(context).enqueueUniquePeriodicWork(
                WORK_TAG,
                ExistingPeriodicWorkPolicy.UPDATE,
                request
            )
        }

        fun cancel(context: Context) {
            WorkManager.getInstance(context).cancelAllWorkByTag(WORK_TAG)
        }
    }
}