PDM2 20201112

package com.joythis.android.distancebetweendates;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.TextView;

import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.ArrayList;

import javax.net.ssl.HttpsURLConnection;

public class StarterActivity extends AppCompatActivity {

    String mRemoteContent = "";
    class MyAsyncTask extends AsyncTask<String, Void, String>{

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mRemoteContent = "";
        }

        @Override
        protected String doInBackground(String... strings) {
            //return null;
            //consumeHttpsResource(SOURCE);
            String strHttpsContent = consumeHttpsResource(strings[0]);
            mRemoteContent = strHttpsContent;
            return strHttpsContent;
        }//doInBackground

        @Override
        protected void onPostExecute(String s) {
            //super.onPostExecute(s);
            populateSpinnerWithLinesFromOnlineTSV(
                mSpnDatesFromTheWeb,
                mRemoteContent
            );
        }
    }//AsyncTask

    Context mContext;

    Button mBtnRequestDate1, mBtnRequestDate2;
    TextView mTvDate1, mTvDate2;
    Button mBtnComputeDistance;

    ListView mLvFeedback; //vis
    ArrayAdapter<String> mAd;
    ArrayList<String> mAlComputedDistances; //data

    AmCalendar mDate1, mDate2;

    Button.OnClickListener mButtonClickHandler =
        new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int id = v.getId();
                switch(id){
                    case R.id.idBtnRequestDate1:
                        actionRequestDate1();
                        break;
                    case R.id.idBtnRequestDate2:
                        actionRequestDate2();
                        break;
                    case R.id.idBtnComputeDistance:
                        actionComputeDistance();
                        break;
                }//switch
            }//onClick
        };//mButtonClickHandler

    public final
        static int
            CALL_ME_ON_THIS_CODE_WHEN_YOU_HAVE_DATE1 = 444;

    public final
    static int
            CALL_ME_ON_THIS_CODE_WHEN_YOU_HAVE_DATE2 = 888;

    public final static int DEFAULT_YEAR = 2020;
    public final static int DEFAULT_MONTH = 11;
    public final static int DEFAULT_DAY = 12;

    @Override
    protected void onActivityResult
    (int requestCode, //who is Android calling?
     int resultCode, //OK or CANCEL ?
     @Nullable Intent data //this will transport the "result(s)"
    )
    {
        super.onActivityResult(requestCode, resultCode, data);

        boolean bUserConfirmedDate = resultCode == RESULT_OK;
        boolean bUserCanceled = resultCode == RESULT_CANCELED;

        if (bUserConfirmedDate){
            //data extraction!
            boolean bIsThereDateToExtractFrom = data!=null;

            if (bIsThereDateToExtractFrom){
                //extraction time!
                int y, m, d;
                y = data.getIntExtra(
                    DateInputActivity.KEY_YEAR,
                    DEFAULT_YEAR
                );

                m = data.getIntExtra(
                    DateInputActivity.KEY_MONTH,
                    DEFAULT_MONTH
                );

                d = data.getIntExtra(
                    DateInputActivity.KEY_DAY,
                    DEFAULT_DAY
                );

                String strDate = String.format(
                    "%d-%d-%d", y, m, d
                );
                //end of extraction

                switch(requestCode){
                    case CALL_ME_ON_THIS_CODE_WHEN_YOU_HAVE_DATE1:
                        //TODO
                        //code to display the recv date in mTvDate1
                        mTvDate1.setText(strDate);
                        mDate1 = new AmCalendar(y,m,d);
                        break;
                        //TODO
                    case CALL_ME_ON_THIS_CODE_WHEN_YOU_HAVE_DATE2:
                        //code to display the recv date in mTvDate2
                        mTvDate2.setText(strDate);
                        mDate2 = new AmCalendar(y,m,d);
                        break;
                }//switch
            }//if there is data to extract from

            if (mDate1!=null && mDate2!=null){
                mBtnComputeDistance.setEnabled(true);
            }//if
        }//the user did NOT cancel, but CONFIRMED / OKed the response
    }//onActivityResult

    void actionRequestDate1(){
        Intent intentToGoPickSomeDateViaDateInputActivity =
            new Intent(
                this,
                DateInputActivity.class
            );

        //startActivity(intentToGoPickSomeDateViaDateInputActivity);

        startActivityForResult(
            intentToGoPickSomeDateViaDateInputActivity,
            CALL_ME_ON_THIS_CODE_WHEN_YOU_HAVE_DATE1
        );
    }//actionRequestDate1

    void actionRequestDate2(){
        Intent intentToGoPickSomeDateViaDateInputActivity =
            new Intent(
                this,
                DateInputActivity.class
            );

        //startActivity(intentToGoPickSomeDateViaDateInputActivity);

        startActivityForResult(
            intentToGoPickSomeDateViaDateInputActivity,
            CALL_ME_ON_THIS_CODE_WHEN_YOU_HAVE_DATE2
        );
    }//actionRequestDate2

    void actionComputeDistance(){
        boolean bCanEnableComputeDistance =
            mDate1!=null & mDate2!=null;

        if (bCanEnableComputeDistance){
            int iDistanceInDays =
                mDate1.distanceInDaysToOtherAmCalendar(mDate2);

            /*
            int iDistanceInDays =
                mDate2.distanceInDaysToOtherAmCalendar(mDate1);
             */

            String strMsg = getString(
                R.string.strDistanceBetweenDays,
                mDate1.toString(),
                mDate2.toString(),
                iDistanceInDays
            );
            mAlComputedDistances.add(0, strMsg);
            mAd.notifyDataSetChanged();
        }//if
    }//actionComputeDistance

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_starter_rl);

        init();
    }//onCreate

    Spinner mSpnDatesFromTheWeb;
    void init(){
        mContext = this;

        mSpnDatesFromTheWeb = findViewById(R.id.idSpnDatesFromTheWeb);

        //DO NOT!
        //android.os.NetworkOnMainThreadException
        /*
        populateSpinnerWithLinesFromOnlineTSV(
            mSpnDatesFromTheWeb,
            consumeHttpsResource(SOURCE)
        );

         */

        //do it async
        MyAsyncTask t = new MyAsyncTask();
        t.execute(SOURCE);

        mBtnRequestDate1 = findViewById(R.id.idBtnRequestDate1);
        mBtnRequestDate2 = findViewById(R.id.idBtnRequestDate2);

        mTvDate1 = findViewById(R.id.idTvDate1);
        mTvDate2 = findViewById(R.id.idTvDate2);

        mBtnComputeDistance =
            findViewById(R.id.idBtnComputeDistance);

        mLvFeedback = findViewById(R.id.idLvFeedback);
        mAlComputedDistances = new ArrayList<>();
        mAd = new ArrayAdapter<>(
            mContext,
            android.R.layout.simple_list_item_1,
            mAlComputedDistances
        );
        mLvFeedback.setAdapter(mAd);

        Button[] aBtns = {
            mBtnRequestDate1,
            mBtnRequestDate2,
            mBtnComputeDistance
        };
        for (Button b : aBtns){
            b.setOnClickListener(mButtonClickHandler);
        }//for

        //makes the Button ignore any user input
        mBtnComputeDistance.setEnabled(false);
    }//init

    /*
    TODO: put it in AmUtil?
     */
    void populateSpinnerWithLinesFromOnlineTSV(
        Spinner pSpn,
        String pOnlineTSVContent

    ){
        String[] aLinesFromTheWWW = pOnlineTSVContent.split("\n");

        ArrayAdapter<String> ad = new ArrayAdapter<>(
            mContext,
            android.R.layout.simple_spinner_item,
            aLinesFromTheWWW
        );

        ad.setDropDownViewResource(
            android.R.layout.simple_spinner_dropdown_item
        );

        pSpn.setAdapter(ad);
    }//populateSpinnerWithLinesFromOnlineTSV

    public final static String SOURCE =
        "https://arturmarques.com/edu/pdm2/dates.TSV";

    public String consumeHttpsResource(
        String pUrl
    ){
        try{
            URL url = new URL(pUrl);
            HttpsURLConnection httpsCon =
                (HttpsURLConnection)url.openConnection();
            InputStream is = httpsCon.getInputStream();
            InputStreamReader isr = new InputStreamReader(is);

            char c; int iByte; String strAll = "";

            while((iByte=isr.read())!=-1){
                c = (char)iByte;
                strAll += c;
            }//while

            isr.close();
            is.close();
            httpsCon.disconnect();

            return strAll;
        }//try
        catch (Exception e){
            Log.e(
                getClass().getName(),
                e.toString()
            );
        }//catch

        return "";
    }//consumeHttpsResource
}//StarterActivity