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package com.example.firebasestorageexample

import android.app.Activity
import android.content.Intent
import android.net.Uri
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.provider.MediaStore
import com.google.android.gms.tasks.Continuation
import com.google.android.gms.tasks.Task
import com.google.firebase.storage.FirebaseStorage
import com.google.firebase.storage.StorageReference
import com.google.firebase.storage.UploadTask
import kotlinx.android.synthetic.main.activity_main.*
import java.io.IOException
import java.util.*

class MainActivity : AppCompatActivity() {

    private val PICK_IMAGE_REQUEST = 71
    private var filePath: Uri? = null
    private var FirebaseStorage: FirebaseStorage? = null
    private var storageReference: StorageReference? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        btn_chose_img.setOnClickListener{ launchGallery() }
        btn_upload_img.setOnClickListener{ uploadImage() }
    }

    private fun launchGallery(){
        val i = Intent()
        i.type = "image/*"
        i.action = Intent.ACTION_GET_CONTENT
        startActivityForResult(Intent.createChooser(i, "Select Picture"), PICK_IMAGE_REQUEST)
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (requestCode == PICK_IMAGE_REQUEST && resultCode == Activity.RESULT_OK){
            if (data == null || data.data == null){
                return
            }
            filePath = data.data
            try {
                val bitmap = MediaStore.Images.Media.getBitmap(contentResolver, filePath)
                img_preview.setImageBitmap(bitmap)
            }catch (e : IOException){
                e.printStackTrace()
            }
        }
    }

    private fun uploadImage(){
        if (filePath != null){
            val ref = storageReference?.child("Uploads/" + UUID.randomUUID().toString())
            val uploadTask = ref?.putFile(filePath!!)

            val urlTask = uploadTask?.continueWithTask(Continuation<UploadTask.TaskSnapshot, Task<Uri>>{
                if (!it.isSuccessful) {
                    it.exception?.let { throw it}
                }
                return@Continuation ref.downloadUrl
            })?.addOnCompleteListener{
                if (it.isSuccessful) {
                    val downloadUri = it.result
                    addUploadRecordToDb (downloadUri.toString())
                }else {

                }
            }?.addOnFailureListener{

            }
        }
    }

    private fun addUploadRecordToDb(uri: String) {

    }
}