package expo.modules.esimmanager

import android.app.Service
import android.content.Intent
import android.os.IBinder
import android.service.euicc.ICarrierEuiccProvisioningService
import android.service.euicc.IGetActivationCodeCallback
import android.util.Log


class CarrierEuiccProvisioningService : Service() {

    override fun onBind(intent: Intent): IBinder {
        return binder
    }

    private val binder = object : ICarrierEuiccProvisioningService.Stub() {
        override fun getActivationCode(callback: IGetActivationCodeCallback?) {
            callback?.onSuccess(activationCode)
        }

        override fun getActivationCodeForEid(eid: String?, callback: IGetActivationCodeCallback?) {
            callback?.onSuccess(activationCode)
        }
    }

    companion object {
        var activationCode = ""
            private set

        fun setActivationCode(value: String) {
            try {
                val validatedCode = validateAndFormatLpaCode(value)
                activationCode = validatedCode
                Log.d("CarrierEuiccProvisioningService", "Activation code set successfully")
            } catch (e: IllegalArgumentException) {
                Log.e("CarrierEuiccProvisioningService", "Invalid activation code: ${e.message}")
                throw e
            }
        }

        private fun validateAndFormatLpaCode(code: String): String {
            if (code.isBlank()) {
                throw IllegalArgumentException("Activation code cannot be empty")
            }

            if (code.length > 1000) {
                throw IllegalArgumentException("Activation code too long (max 1000 characters)")
            }

            val dangerousChars = listOf("<", ">", "\"", "'", "&", "script", "javascript")
            for (char in dangerousChars) {
                if (code.contains(char, ignoreCase = true)) {
                    throw IllegalArgumentException("Activation code contains invalid characters")
                }
            }

            val formattedCode = if (code.startsWith("LPA:")) {
                code
            } else {
                "LPA:$code"
            }

            if (!isValidLpaFormat(formattedCode)) {
                throw IllegalArgumentException("Invalid LPA code format. Expected: LPA:1\$server\$code")
            }

            return formattedCode
        }

        private fun isValidLpaFormat(code: String): Boolean {
            val pattern = Regex("^LPA:\\d+\\$[^\\$]+\\$[A-Z0-9-]+$")
            
            if (!pattern.matches(code)) {
                return false
            }

            val parts = code.split("$")
            if (parts.size != 3) {
                return false
            }

            if (parts[0] != "LPA:1") {
                return false
            }

            if (parts[1].isBlank()) {
                return false
            }

            if (parts[2].isBlank()) {
                return false
            }

            return true
        }

        fun clearActivationCode() {
            activationCode = ""
            Log.d("CarrierEuiccProvisioningService", "Activation code cleared")
        }
    }
}