package com.catlas.escapepenacony.data

import android.content.Context
import android.content.Intent
import android.net.Uri
import android.os.Build
import android.os.Environment
import android.provider.Settings
import androidx.core.content.FileProvider
import com.catlas.escapepenacony.BuildConfig
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.withContext
import org.json.JSONObject
import java.io.File
import java.io.FileOutputStream
import java.net.HttpURLConnection
import java.net.URL

data class ReleaseInfo(
    val tagName: String,
    val releaseTitle: String,
    val changelog: String,
    val apkDownloadUrl: String,
    val isNewer: Boolean
)

object UpdateManager {

    private const val GITHUB_RELEASES_API =
        "https://api.github.com/repos/CAtlas0784/Escape-penacony/releases/latest"

    private const val GITHUB_RAW_SCENES_URL =
        "https://raw.githubusercontent.com/CAtlas0784/Escape-penacony/main/scenes.json"

    suspend fun checkForAppUpdate(currentVersion: String = BuildConfig.VERSION_NAME): Result<ReleaseInfo?> =
        withContext(Dispatchers.IO) {
            try {
                val url = URL(GITHUB_RELEASES_API)
                val conn = url.openConnection() as HttpURLConnection
                conn.connectTimeout = 8000
                conn.readTimeout = 8000
                conn.setRequestProperty("Accept", "application/vnd.github.v3+json")
                conn.setRequestProperty("User-Agent", "Escape-Penacony-Android-App")

                if (conn.responseCode == 200) {
                    val body = conn.inputStream.bufferedReader().use { it.readText() }
                    val json = JSONObject(body)
                    val tagName = json.getString("tag_name")
                    val title = json.optString("name", tagName)
                    val changelog = json.optString("body", "No changelog provided.")

                    var downloadUrl = ""
                    val assets = json.optJSONArray("assets")
                    if (assets != null) {
                        for (i in 0 until assets.length()) {
                            val asset = assets.getJSONObject(i)
                            val name = asset.optString("name", "")
                            if (name.endsWith(".apk", ignoreCase = true)) {
                                downloadUrl = asset.getString("browser_download_url")
                                break
                            }
                        }
                    }

                    val isNewer = isNewerVersion(currentVersion, tagName)
                    Result.success(
                        ReleaseInfo(
                            tagName = tagName,
                            releaseTitle = title,
                            changelog = changelog,
                            apkDownloadUrl = downloadUrl,
                            isNewer = isNewer
                        )
                    )
                } else {
                    Result.success(null)
                }
            } catch (e: Exception) {
                e.printStackTrace()
                Result.failure(e)
            }
        }

    suspend fun downloadApk(
        context: Context,
        downloadUrl: String,
        onProgress: (Int) -> Unit
    ): Result<File> = withContext(Dispatchers.IO) {
        try {
            val url = URL(downloadUrl)
            val conn = url.openConnection() as HttpURLConnection
            conn.connectTimeout = 15000
            conn.readTimeout = 15000
            conn.setRequestProperty("User-Agent", "Escape-Penacony-Android-App")

            val fileLength = conn.contentLength
            val dir = context.getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS) ?: context.filesDir
            val apkFile = File(dir, "Escape-penacony-update.apk")

            conn.inputStream.use { input ->
                FileOutputStream(apkFile).use { output ->
                    val buffer = ByteArray(8 * 1024)
                    var total: Long = 0
                    var count: Int
                    while (input.read(buffer).also { count = it } != -1) {
                        total += count
                        if (fileLength > 0) {
                            val progress = ((total * 100) / fileLength).toInt()
                            withContext(Dispatchers.Main) {
                                onProgress(progress)
                            }
                        }
                        output.write(buffer, 0, count)
                    }
                }
            }

            Result.success(apkFile)
        } catch (e: Exception) {
            e.printStackTrace()
            Result.failure(e)
        }
    }

    fun promptInstallApk(context: Context, apkFile: File) {
        // Android 8.0+ Check Unknown App Sources permission
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            if (!context.packageManager.canRequestPackageInstalls()) {
                val settingsIntent = Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES).apply {
                    data = Uri.parse("package:${context.packageName}")
                    addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                }
                context.startActivity(settingsIntent)
                return
            }
        }

        val apkUri: Uri = FileProvider.getUriForFile(
            context,
            "${context.packageName}.fileprovider",
            apkFile
        )

        val installIntent = Intent(Intent.ACTION_VIEW).apply {
            setDataAndType(apkUri, "application/vnd.android.package-archive")
            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
            addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
        }
        context.startActivity(installIntent)
    }

    suspend fun fetchLatestScenesJson(): Result<String> = withContext(Dispatchers.IO) {
        try {
            val url = URL(GITHUB_RAW_SCENES_URL)
            val conn = url.openConnection() as HttpURLConnection
            conn.connectTimeout = 8000
            conn.readTimeout = 8000
            conn.setRequestProperty("User-Agent", "Escape-Penacony-Android-App")

            if (conn.responseCode == 200) {
                val content = conn.inputStream.bufferedReader().use { it.readText() }
                Result.success(content)
            } else {
                Result.failure(Exception("HTTP error ${conn.responseCode}"))
            }
        } catch (e: Exception) {
            Result.failure(e)
        }
    }

    private fun isNewerVersion(current: String, latest: String): Boolean {
        val c = current.removePrefix("v").split(".").map { it.toIntOrNull() ?: 0 }
        val l = latest.removePrefix("v").split(".").map { it.toIntOrNull() ?: 0 }
        val maxLen = maxOf(c.size, l.size)
        for (i in 0 until maxLen) {
            val cv = c.getOrElse(i) { 0 }
            val lv = l.getOrElse(i) { 0 }
            if (lv > cv) return true
            if (lv < cv) return false
        }
        return false
    }
}