Dantotsu/app/src/main/java/ani/dantotsu/connections/mal/MAL.kt

package ani.dantotsu.connections.mal

import android.content.ActivityNotFoundException
import android.content.Context
import android.net.Uri
import android.util.Base64
import androidx.browser.customtabs.CustomTabsIntent
import androidx.fragment.app.FragmentActivity
import ani.dantotsu.*
import kotlinx.serialization.SerialName
import kotlinx.serialization.Serializable
import java.io.File
import java.security.SecureRandom

object MAL {
    val query: MALQueries = MALQueries()
    const val clientId = "86b35cf02205a0303da3aaea1c9e33f3"
    var username: String? = null
    var avatar: String? = null
    var token: String? = null
    var userid: Int? = null

    fun loginIntent(context: Context) {
        val codeVerifierBytes = ByteArray(96)
        SecureRandom().nextBytes(codeVerifierBytes)
        val codeChallenge = Base64.encodeToString(codeVerifierBytes, Base64.DEFAULT).trimEnd('=')
            .replace("+", "-")
            .replace("/", "_")
            .replace("\n", "")

        saveData("malCodeChallenge", codeChallenge, context)
        val request =
            "https://myanimelist.net/v1/oauth2/authorize?response_type=code&client_id=$clientId&code_challenge=$codeChallenge"
        try {
            CustomTabsIntent.Builder().build().launchUrl(
                context,
                Uri.parse(request)
            )
        } catch (e: ActivityNotFoundException) {
            openLinkInBrowser(request)
        }
    }

    private const val MAL_TOKEN = "malToken"

    private suspend fun refreshToken(): ResponseToken? {
        return tryWithSuspend {
            val token = loadData<ResponseToken>(MAL_TOKEN)
                ?: throw Exception(currContext()?.getString(R.string.refresh_token_load_failed))
            val res = client.post(
                "https://myanimelist.net/v1/oauth2/token",
                data = mapOf(
                    "client_id" to clientId,
                    "grant_type" to "refresh_token",
                    "refresh_token" to token.refreshToken
                )
            ).parsed<ResponseToken>()
            saveResponse(res)
            return@tryWithSuspend res
        }
    }


    suspend fun getSavedToken(context: FragmentActivity): Boolean {
        return tryWithSuspend(false) {
            var res: ResponseToken = loadData(MAL_TOKEN, context)
                ?: return@tryWithSuspend false
            if (System.currentTimeMillis() > res.expiresIn)
                res = refreshToken()
                    ?: throw Exception(currContext()?.getString(R.string.refreshing_token_failed))
            token = res.accessToken
            return@tryWithSuspend true
        } ?: false
    }

    fun removeSavedToken(context: Context) {
        token = null
        username = null
        userid = null
        avatar = null
        if (MAL_TOKEN in context.fileList()) {
            File(context.filesDir, MAL_TOKEN).delete()
        }
    }

    fun saveResponse(res: ResponseToken) {
        res.expiresIn += System.currentTimeMillis()
        saveData(MAL_TOKEN, res)
    }

    @Serializable
    data class ResponseToken(
        @SerialName("token_type") val tokenType: String,
        @SerialName("expires_in") var expiresIn: Long,
        @SerialName("access_token") val accessToken: String,
        @SerialName("refresh_token") val refreshToken: String,
    ): java.io.Serializable

}