package moe.yuuta.workmode.access

import android.content.Context
import android.content.pm.LauncherApps
import android.content.pm.PackageManager
import android.os.Bundle
import android.os.PersistableBundle
import android.os.Process
import android.os.UserHandle
import android.system.Os
import moe.yuuta.workmode.BuildConfig
import java.lang.reflect.Field
import java.lang.reflect.Method

/**
 * An layer to access package suspending related APIs, it is a low-level layer which is used to call System APIs directly.
 *
 * TODO: Multi-user support
 */
internal class AccessLayer(private val mContext: Context) {
    private val mPM: PackageManager = mContext.packageManager

    fun setPackagesSuspended(packageNames: Array<String>, suspended: Boolean,
                             appExtras: PersistableBundle, launcherExtras: PersistableBundle,
                             dialogMessage: String): Array<String> {
        // ApplicationPackageManager ALWAYS uses context.getOpPackageName() as the argument "callingPackage"
        // My callingPackage MUSTN'T equals to 'android'
        // If we are using packageName of 'android', system will show disabled
        // by admin dialog instead of suspended dialog
        // F**k Google
        val func: Method = Class.forName("android.content.pm.IPackageManager")
                .getDeclaredMethod("setPackagesSuspendedAsUser",
                        Array<String>::class.java,
                        Boolean::class.java,
                        PersistableBundle::class.java,
                        PersistableBundle::class.java,
                        String::class.java,
                        String::class.java,
                        Int::class.java)

        // It's an unstable design
        val iPM: Field = mPM::class.java.getDeclaredField("mPM")
        iPM.isAccessible = true

        return func.invoke(iPM.get(mPM),
                packageNames,
                suspended,
                appExtras,
                launcherExtras,
                dialogMessage,
                BuildConfig.APPLICATION_ID,
                UserHandle.getUserHandleForUid(mPM.getPackageUid(mContext.packageName, 0)).hashCode()) as Array<String>
    }

    /**
     * This method will SET your UID and you WON'T BE ABLE TO GO BACK.
     * Create a new process and access it.
     */
    fun getSuspendedPackageAppExtras(packageName: String): PersistableBundle? {
        Os.setuid(mPM.getPackageUid(packageName, 0))
        // ApplicationPackageManager ALWAYS uses context.getOpPackageName() as the package name
        // F**k Google
        val func: Method = Class.forName("android.content.pm.IPackageManager")
                .getDeclaredMethod("getSuspendedPackageAppExtras",
                        String::class.java,
                        Int::class.java)

        // It's an unstable design
        val iPM: Field = mPM::class.java.getDeclaredField("mPM")
        iPM.isAccessible = true

        return func.invoke(iPM.get(mPM),
                packageName,
                UserHandle.getUserHandleForUid(mPM.getPackageUid(packageName, 0)).hashCode()) as PersistableBundle?
    }

    @Throws(PackageManager.NameNotFoundException::class)
    fun isPackageSuspended(packageName: String): Boolean {
        val func: Method = PackageManager::class.java.getDeclaredMethod("isPackageSuspended",
                String::class.java)
        return func.invoke(mPM, packageName) as Boolean
    }

    fun getSuspendedPackageLauncherExtras(packageName: String): Bundle? =
            mContext.getSystemService(LauncherApps::class.java).getSuspendedPackageLauncherExtras(packageName, Process.myUserHandle())
}