package joaocsousa.github.com.myapplication;

import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.annotation.StringRes;
import android.support.v4.view.LayoutInflaterCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.TextView;

import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        LayoutInflaterCompat.setFactory2(getLayoutInflater(), new CustomLayoutInflater(this, new StringIdExtractor(), new Translations()));
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public static class CustomLayoutInflater implements LayoutInflater.Factory2 {

        private final AppCompatActivity appCompatActivity;
        private final StringIdExtractor stringIdExtractor;
        private final Translations translations;

        public CustomLayoutInflater(AppCompatActivity appCompatActivity, StringIdExtractor stringIdExtractor, Translations translations) {
            this.appCompatActivity = appCompatActivity;
            this.stringIdExtractor = stringIdExtractor;
            this.translations = translations;
        }

        @Override
        public View onCreateView(View parent, String name, Context context, AttributeSet attributeSet) {
            View view = appCompatActivity.getDelegate().createView(parent, name, context, attributeSet);
            if (view == null) {
                view = appCompatActivity.onCreateView(parent, name, context, attributeSet);
            }
            if (view == null) {
                view = appCompatActivity.onCreateView(name, context, attributeSet);
            }
            if (view != null && view instanceof TextView) {
                int stringId = stringIdExtractor.getStringId(attributeSet);
                String translation = translations.getTranslationFor(stringId);
                ((TextView) view).setText(translation);
            }
            return view;
        }

        @Override
        public View onCreateView(String name, Context context, AttributeSet attributeSet) {
            return null;
        }
    }

    public static class StringIdExtractor {

        public static final int NOT_FOUND = Integer.MIN_VALUE;
        private static final String NAMESPACE = "http://schemas.android.com/apk/res/android";
        private static final String TAG_TEXT = "text";

        @StringRes
        public int getStringId(@Nullable AttributeSet attributeSet) {
            if (attributeSet == null) {
                return NOT_FOUND;
            }
            String stringId = attributeSet.getAttributeValue(NAMESPACE, TAG_TEXT);
            if (stringId != null) {
                stringId = stringId.replace("@", "");
                try {
                    return Integer.valueOf(stringId);
                } catch (NumberFormatException e) {
                    return NOT_FOUND;
                }
            }
            return NOT_FOUND;
        }
    }

    public static class Translations {

        private static final Map<Integer, String> enTranslations = new HashMap<>();
        private static final Map<Integer, String> frTranslations = new HashMap<>();
        private static final Map<Integer, String> DEFAULT_TRANSLATIONS = enTranslations;

        static {
            enTranslations.put(R.string.whatever, "Whatever (English)");
            frTranslations.put(R.string.whatever, "Whatever (French)");
            
            enTranslations.put(R.string.hello, "Hello (English)");
            frTranslations.put(R.string.hello, "Hello (French)");
        }

        public String getTranslationFor(@StringRes int resId) {
            if (Locale.getDefault().getISO3Language().equals(Locale.FRANCE.getISO3Language())) {
                return frTranslations.get(resId);
            } else if (Locale.getDefault().getISO3Language().equals(Locale.UK.getISO3Language())) {
                return enTranslations.get(resId);
            } else {
                return DEFAULT_TRANSLATIONS.get(resId);
            }
        }
    }

}