package com.peachpasswords.license

import android.content.Context
import androidx.security.crypto.EncryptedSharedPreferences
import androidx.security.crypto.MasterKey
import dagger.hilt.android.qualifiers.ApplicationContext
import javax.inject.Inject
import javax.inject.Singleton

/**
 * Validation lives in [LicenseCodec]; this class owns storage only.
 */
@Singleton
class LicenseRepository @Inject constructor(@ApplicationContext context: Context) {
    companion object {
        private const val PREFS_FILE = "peach_license_prefs"
        private const val KEY_LICENSE = "peach_license"
        private const val KEY_PRO_CELEBRATED = "peach_pro_celebrated"
    }

    private val masterKey = MasterKey.Builder(context)
        .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
        .build()

    private val prefs = EncryptedSharedPreferences.create(
        context,
        PREFS_FILE,
        masterKey,
        EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
        EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM,
    )

    fun storeLicense(key: String): Boolean {
        if (!validateLicense(key)) return false
        prefs.edit()
            .putString(KEY_LICENSE, key)
            .remove(KEY_PRO_CELEBRATED)
            .apply()
        return true
    }

    fun getLicenseKey(): String? = prefs.getString(KEY_LICENSE, null)

    fun getLicenseIssuedAtMillis(): Long? = getLicenseKey()?.let(::licenseIssuedAtMillis)

    fun clearLicense() = prefs.edit().remove(KEY_LICENSE).apply()

    fun isProCelebrated(): Boolean = prefs.getBoolean(KEY_PRO_CELEBRATED, false)

    fun markProCelebrated() = prefs.edit().putBoolean(KEY_PRO_CELEBRATED, true).apply()

    fun isProActive(): Boolean = getLicenseKey()?.let(::validateLicense) == true

    // The signed payload is only 12 bytes and carries no per-feature data; gates use the licence verdict directly.
    fun hasFeature(): Boolean = isProActive()

    fun validateLicense(licenseKey: String): Boolean = LicenseCodec.validate(licenseKey)

    fun licenseIssuedAtMillis(licenseKey: String): Long? = LicenseCodec.issuedAtMillis(licenseKey)
}