// inMOLA Analytics — Android SDK (tek dosya, bağımlılık yok). minSdk 16+.
//
// Kurulum: bu dosyayı projenize ekleyin (paket adını değiştirebilirsiniz). AndroidManifest.xml'de INTERNET izni olmalı:
//   <uses-permission android:name="android.permission.INTERNET" />
//   Application.onCreate():   InmolaAnalytics.init(this, "SITE_ANAHTARI")
//   Ekran:                    InmolaAnalytics.screen("Ürün Detay")
//                             (Activity'ler kendiliğinden ekran sayılır; Compose / tek Activity'de screen() çağırın)
//   Olay:                     InmolaAnalytics.event("sepete_ekle", "SKU-1")
//   Satın alma:               InmolaAnalytics.purchase("SIP-1001", 1499.90, "TRY",
//                                 listOf(InmolaAnalytics.Item("SKU-1", "Ürün", 1499.90, 1)))
//
// Gizlilik: reklam kimliği / Android ID KULLANILMAZ, cihaza hiçbir şey yazılmaz, kişisel veri gönderilmez.
// Kayıtlar bellekte toplanır, ~10 sn'de bir ve uygulama arka plana geçerken gönderilir.

package com.inmola.analytics

import android.app.Activity
import android.app.Application
import android.os.Build
import android.os.Bundle
import java.net.HttpURLConnection
import java.util.Locale
import java.util.concurrent.Executors
import java.util.concurrent.ScheduledExecutorService
import java.util.concurrent.TimeUnit

object InmolaAnalytics {
    data class Item(val id: String, val name: String, val price: Double, val quantity: Int = 1)

    /** Gönderim kapalı (ör. kullanıcı analitiği reddettiyse). Kapalıyken hiçbir şey toplanmaz. */
    @Volatile var enabled = true
    /** Activity'leri kendiliğinden ekran olarak say (sınıf adıyla, "Activity" eki atılır). */
    @Volatile var autoScreens = true

    private var core: Core? = null
    private var started = 0

    @JvmStatic @JvmOverloads
    fun init(app: Application, siteKey: String, endpoint: String = Core.DEFAULT_ENDPOINT) {
        if (core != null) return
        val res = app.resources
        val version = try { app.packageManager.getPackageInfo(app.packageName, 0).versionName ?: "" } catch (e: Exception) { "" }
        val loc = Locale.getDefault()
        val c = Core(siteKey, endpoint, mapOf(
            "b" to app.packageName.lowercase(Locale.ROOT), "p" to "android", "ov" to (Build.VERSION.RELEASE ?: ""),
            "dm" to (Build.MODEL ?: ""), "av" to version, "l" to loc.language + (if (loc.country.isNotEmpty()) "-" + loc.country else ""),
            "tab" to (if (res.configuration.smallestScreenWidthDp >= 600) 1 else 0),
            "w" to (res.displayMetrics.widthPixels / res.displayMetrics.density).toInt()))
        core = c
        app.registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {
            override fun onActivityStarted(a: Activity) { if (started++ == 0) c.foreground() }
            override fun onActivityStopped(a: Activity) { if (--started == 0) c.background() }
            override fun onActivityResumed(a: Activity) { if (autoScreens) c.screen(a.javaClass.simpleName.removeSuffix("Activity").ifEmpty { "Main" }) }
            override fun onActivityCreated(a: Activity, b: Bundle?) {}
            override fun onActivityPaused(a: Activity) {}
            override fun onActivitySaveInstanceState(a: Activity, b: Bundle) {}
            override fun onActivityDestroyed(a: Activity) {}
        })
    }

    /** Ekran açıldı. Elle çağırdığınızda Activity adıyla otomatik sayımı kapatmak için autoScreens = false yapın. */
    @JvmStatic fun screen(name: String) { if (enabled) core?.screen(name) }

    @JvmStatic @JvmOverloads fun event(name: String, detail: String = "") { if (enabled) core?.event(name, detail) }

    @JvmStatic @JvmOverloads
    fun purchase(transactionId: String, value: Double, currency: String, items: List<Item> = emptyList()) {
        if (enabled) core?.purchase(transactionId, value, currency, items)
    }

    /** Android'den bağımsız çekirdek (JVM'de test edilebilir): kuyruk, oturum, gönderim. */
    class Core(private val key: String, private val endpoint: String, private val base: Map<String, Any>) {
        companion object { const val DEFAULT_ENDPOINT = "https://inmola-analytics.iletisim-845.workers.dev/m" }
        private val ex: ScheduledExecutorService = Executors.newSingleThreadScheduledExecutor()
        private val pending = ArrayList<Map<String, Any>>()
        private var screen: String? = null
        private var screenStart = 0L
        private var screenEntry = false
        private var newSession = true
        private var backgroundAt = 0L

        init { ex.scheduleWithFixedDelay({ flush() }, 10, 10, TimeUnit.SECONDS) }

        fun screen(name: String) = ex.execute { show(name, System.currentTimeMillis()) }
        fun event(name: String, detail: String) = ex.execute { add(mapOf("t" to "ev", "sc" to (screen ?: ""), "n" to name, "dd" to detail)) }
        fun purchase(tx: String, value: Double, currency: String, items: List<Item>) = ex.execute {
            add(mapOf("t" to "ev", "sc" to (screen ?: ""), "n" to "purchase", "dd" to tx, "v" to value,
                "cur" to currency.uppercase(Locale.ROOT),
                "it" to items.take(50).map { mapOf("n" to it.name, "id" to it.id, "p" to it.price, "q" to it.quantity) }))
            flush()
        }
        fun background() = ex.execute { backgroundAt = System.currentTimeMillis(); end(false, backgroundAt); flush() }
        fun foreground() = ex.execute {
            val away = if (backgroundAt > 0) System.currentTimeMillis() - backgroundAt else 0
            backgroundAt = 0
            val s = screen ?: return@execute
            newSession = away > 30 * 60 * 1000   // 30 dk'dan uzun arka plan = yeni oturum
            screen = null
            show(s, System.currentTimeMillis())
        }
        /** Test için: bekleyen kayıtları hemen gönder ve bitmesini bekle. */
        fun flushNow() { ex.submit { flush() }.get() }

        private fun show(name: String, now: Long) {
            if (name == screen) return
            end(true, now)
            screen = name; screenStart = now; screenEntry = newSession
            add(mapOf("t" to "pv", "sc" to name, "ent" to if (newSession) 1 else 0))
            newSession = false
        }
        private fun end(next: Boolean, now: Long) {
            val s = screen ?: return
            add(mapOf("t" to "en", "sc" to s, "sec" to minOf((now - screenStart) / 1000, 3600L), "nx" to if (next) 1 else 0,
                "ent" to if (screenEntry) 1 else 0))
        }
        private fun add(e: Map<String, Any>) {
            if (!InmolaAnalytics.enabled || key.isEmpty()) return
            pending.add(e)
            if (pending.size >= 20) flush()
        }
        private fun flush() {
            if (pending.isEmpty()) return
            val batch = ArrayList(pending.take(50))
            repeat(batch.size) { pending.removeAt(0) }
            val body = HashMap(base).apply { put("s", key); put("ev", batch) }
            var ok = false
            try {
                val c = java.net.URI(endpoint).toURL().openConnection() as HttpURLConnection
                c.requestMethod = "POST"; c.doOutput = true; c.connectTimeout = 10000; c.readTimeout = 10000
                c.setRequestProperty("Content-Type", "text/plain")
                c.outputStream.use { it.write(json(body).toByteArray(Charsets.UTF_8)) }
                ok = c.responseCode < 500
                c.disconnect()
            } catch (e: Exception) { }
            // Ağ yoksa geri koy (bellekte en fazla 200 kayıt), sonraki turda tekrar denenir
            if (!ok && pending.size < 200) pending.addAll(0, batch)
        }
        private fun json(v: Any?): String = when (v) {
            null -> "null"
            is String -> "\"" + v.flatMap { ch -> when {
                ch == '"' -> listOf('\\', '"'); ch == '\\' -> listOf('\\', '\\')
                ch < ' ' -> String.format("\\u%04x", ch.code).toList(); else -> listOf(ch) } }.joinToString("") + "\""
            is Number, is Boolean -> v.toString()
            is Map<*, *> -> v.entries.joinToString(",", "{", "}") { json(it.key.toString()) + ":" + json(it.value) }
            is List<*> -> v.joinToString(",", "[", "]") { json(it) }
            else -> json(v.toString())
        }
    }
}