package org.schabi.newpipe.fragments.detail

import android.view.ViewGroup
import androidx.fragment.app.Fragment
import androidx.fragment.app.FragmentManager
import androidx.fragment.app.FragmentPagerAdapter

class TabAdapter // if changed to BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT => crash if enqueueing stream in
// the background and then clicking on it to open VideoDetailFragment:
// "Cannot setMaxLifecycle for Fragment not attached to FragmentManager"
(private val fragmentManager: FragmentManager) : FragmentPagerAdapter(fragmentManager, BEHAVIOR_SET_USER_VISIBLE_HINT) {
    private val mFragmentList: MutableList<Fragment> = ArrayList()
    private val mFragmentTitleList: MutableList<String?> = ArrayList()
    public override fun getItem(position: Int): Fragment {
        return mFragmentList.get(position)
    }

    public override fun getCount(): Int {
        return mFragmentList.size
    }

    fun addFragment(fragment: Fragment, title: String?) {
        mFragmentList.add(fragment)
        mFragmentTitleList.add(title)
    }

    fun clearAllItems() {
        mFragmentList.clear()
        mFragmentTitleList.clear()
    }

    fun removeItem(position: Int) {
        mFragmentList.removeAt(if (position == 0) 0 else position - 1)
        mFragmentTitleList.removeAt(if (position == 0) 0 else position - 1)
    }

    fun updateItem(position: Int, fragment: Fragment) {
        mFragmentList.set(position, fragment)
    }

    fun updateItem(title: String?, fragment: Fragment) {
        val index: Int = mFragmentTitleList.indexOf(title)
        if (index != -1) {
            updateItem(index, fragment)
        }
    }

    public override fun getItemPosition(`object`: Any): Int {
        if (mFragmentList.contains(`object`)) {
            return mFragmentList.indexOf(`object`)
        } else {
            return POSITION_NONE
        }
    }

    fun getItemPositionByTitle(title: String?): Int {
        return mFragmentTitleList.indexOf(title)
    }

    fun getItemTitle(position: Int): String? {
        if (position < 0 || position >= mFragmentTitleList.size) {
            return null
        }
        return mFragmentTitleList.get(position)
    }

    fun notifyDataSetUpdate() {
        notifyDataSetChanged()
    }

    public override fun destroyItem(container: ViewGroup,
                                    position: Int,
                                    `object`: Any) {
        fragmentManager.beginTransaction().remove((`object` as Fragment?)!!).commitNowAllowingStateLoss()
    }
}