/*
 * Copyright (C) 2011 University of Washington
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package org.odk.collect.android.widgets;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.graphics.Typeface;
import android.support.v4.content.ContextCompat;
import android.util.Log;
import android.util.TypedValue;
import android.view.Display;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.view.inputmethod.InputMethodManager;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ImageView.ScaleType;
import android.widget.ListView;
import android.widget.TextView;

import org.javarosa.core.model.SelectChoice;
import org.javarosa.core.model.data.IAnswerData;
import org.javarosa.core.model.data.SelectMultiData;
import org.javarosa.core.model.data.helper.Selection;
import org.javarosa.core.reference.InvalidReferenceException;
import org.javarosa.core.reference.ReferenceManager;
import org.javarosa.form.api.FormEntryCaption;
import org.javarosa.form.api.FormEntryPrompt;
import org.javarosa.xpath.expr.XPathFuncExpr;
import org.odk.collect.android.R;
import org.odk.collect.android.application.Collect;
import org.odk.collect.android.external.ExternalDataUtil;
import org.odk.collect.android.external.ExternalSelectChoice;
import org.odk.collect.android.utilities.FileUtils;
import org.odk.collect.android.views.AudioButton.AudioHandler;
import org.odk.collect.android.views.ExpandedHeightGridView;

import java.io.File;
import java.util.Vector;

/**
 * GridWidget handles multiple selection fields using a grid of icons. The user clicks the desired icon and the
 * background changes from black to orange. If text, audio or video are specified in the select answers they are
 * ignored. This is almost identical to GridWidget, except multiple icons can be selected simultaneously.
 *
 * @author Jeff Beorse (jeff@beorse.net)
 */
public class GridMultiWidget extends QuestionWidget {

  // The RGB value for the orange background
  public static final int orangeRedVal = 255;
  public static final int orangeGreenVal = 140;
  public static final int orangeBlueVal = 0;

  private static final int HORIZONTAL_PADDING = 7;
  private static final int VERTICAL_PADDING = 5;
  private static final int SPACING = 2;
  private static final int IMAGE_PADDING = 8;
  private static final int SCROLL_WIDTH = 16;

  Vector<SelectChoice> mItems;

  // The possible select choices
  String[] choices;

  // The Gridview that will hold the icons
  ExpandedHeightGridView gridview;

  // Defines which icon is selected
  boolean[] selected;

  // The image views for each of the icons
  View[] imageViews;
  AudioHandler[] audioHandlers;

  // need to remember the last click position for audio treatment
  int lastClickPosition = 0;

  // The number of columns in the grid, can be user defined (<= 0 if unspecified)
  int numColumns;

  int resizeWidth;

  @SuppressWarnings("unchecked")
  public GridMultiWidget(Context context, FormEntryPrompt prompt, int numColumns) {
    super(context, prompt);

    // SurveyCTO-added support for dynamic select content (from .csv files)
    XPathFuncExpr xPathFuncExpr = ExternalDataUtil.getSearchXPathExpression(prompt.getAppearanceHint());
    if (xPathFuncExpr != null) {
      mItems = ExternalDataUtil.populateExternalChoices(prompt, xPathFuncExpr);
    } else {
      mItems = prompt.getSelectChoices();
    }
    mPrompt = prompt;

    selected = new boolean[mItems.size()];
    choices = new String[mItems.size()];
    gridview = new ExpandedHeightGridView(context);
    imageViews = new View[mItems.size()];
    audioHandlers = new AudioHandler[mItems.size()];
    // The max width of an icon in a given column. Used to line
    // up the columns and automatically fit the columns in when
    // they are chosen automatically
    int maxColumnWidth = -1;
    int maxCellHeight = -1;
    this.numColumns = numColumns;
    for (int i = 0; i < mItems.size(); i++) {
      imageViews[i] = new ImageView(getContext());
    }

    Display display =
        ((WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE))
            .getDefaultDisplay();
    int screenWidth = display.getWidth();
    int screenHeight = display.getHeight();

    if (display.getOrientation() % 2 == 1) {
      // rotated 90 degrees...
      int temp = screenWidth;
      screenWidth = screenHeight;
      screenHeight = temp;
    }

    if (numColumns > 0) {
      resizeWidth = ((screenWidth - 2 * HORIZONTAL_PADDING - SCROLL_WIDTH - (IMAGE_PADDING + SPACING) * numColumns) /
          numColumns);
    }

    // Build view
    for (int i = 0; i < mItems.size(); i++) {
      SelectChoice sc = mItems.get(i);

      int curHeight = -1;

      // Create an audioHandler iff there is an audio prompt associated with this selection.
      String audioURI =
          prompt.getSpecialFormSelectChoiceText(sc, FormEntryCaption.TEXT_FORM_AUDIO);
      if (audioURI != null) {
        audioHandlers[i] = new AudioHandler(prompt.getIndex(), sc.getValue(), audioURI);
      } else {
        audioHandlers[i] = null;
      }
      // Read the image sizes and set maxColumnWidth. This allows us to make sure all of our
      // columns are going to fit
      String imageURI;
      if (mItems.get(i) instanceof ExternalSelectChoice) {
        imageURI = ((ExternalSelectChoice) sc).getImage();
      } else {
        imageURI = prompt.getSpecialFormSelectChoiceText(sc, FormEntryCaption.TEXT_FORM_IMAGE);
      }

      String errorMsg = null;
      if (imageURI != null) {
        choices[i] = imageURI;

        String imageFilename;
        try {
          imageFilename = ReferenceManager._().DeriveReference(imageURI).getLocalURI();
          final File imageFile = new File(imageFilename);
          if (imageFile.exists()) {
            Bitmap b =
                FileUtils
                    .getBitmapScaledToDisplay(imageFile, screenHeight, screenWidth);
            if (b != null) {

              if (b.getWidth() > maxColumnWidth) {
                maxColumnWidth = b.getWidth();
              }

              ImageView imageView = (ImageView) imageViews[i];

              imageView.setBackgroundColor(Color.WHITE);

              if (numColumns > 0) {
                int resizeHeight = (b.getHeight() * resizeWidth) / b.getWidth();
                b = Bitmap.createScaledBitmap(b, resizeWidth, resizeHeight, false);
              }

              imageView.setPadding(IMAGE_PADDING, IMAGE_PADDING, IMAGE_PADDING, IMAGE_PADDING);
              imageView.setImageBitmap(b);
              imageView.setLayoutParams(new ListView.LayoutParams(ListView.LayoutParams.WRAP_CONTENT, ListView
                  .LayoutParams.WRAP_CONTENT));
              imageView.setScaleType(ScaleType.FIT_XY);

              imageView.measure(0, 0);
              curHeight = imageView.getMeasuredHeight();
            } else {
              // Loading the image failed, so it's likely a bad file.
              errorMsg = getContext().getString(R.string.file_invalid, imageFile);
            }
          } else {
            // We should have an image, but the file doesn't exist.
            errorMsg = getContext().getString(R.string.file_missing, imageFile);
          }
        } catch (InvalidReferenceException e) {
          Log.e("GridMultiWidget", "image invalid reference exception");
          e.printStackTrace();
        }
      } else {
        errorMsg = "";
      }

      if (errorMsg != null) {
        choices[i] = prompt.getSelectChoiceText(sc);

        TextView missingImage = new TextView(getContext());
        missingImage.setTextSize(TypedValue.COMPLEX_UNIT_DIP, mAnswerFontsize);
        missingImage.setGravity(Gravity.CENTER_VERTICAL | Gravity.START);
        missingImage.setPadding(IMAGE_PADDING, IMAGE_PADDING, IMAGE_PADDING, IMAGE_PADDING);
        missingImage.setTextSize(TypedValue.COMPLEX_UNIT_PX, getResources().getDimension(R.dimen.question_text));
        missingImage.setTextColor(ContextCompat.getColor(context, R.color.question_text));
        missingImage.setTypeface(null, Typeface.NORMAL);

        if (choices[i] != null && choices[i].length() != 0) {
          missingImage.setText(choices[i]);
        } else {
          // errorMsg is only set when an error has occurred
          Log.e("GridMultiWidget", errorMsg);
          missingImage.setText(errorMsg);
        }

        if (numColumns > 0) {
          maxColumnWidth = resizeWidth;
          // force the max width to find the needed height...
          missingImage.setMaxWidth(resizeWidth);
          missingImage.measure(MeasureSpec.makeMeasureSpec(resizeWidth, MeasureSpec.EXACTLY), 0);
          curHeight = missingImage.getMeasuredHeight();
        } else {
          missingImage.measure(0, 0);
          int width = missingImage.getMeasuredWidth();
          if (width > maxColumnWidth) {
            maxColumnWidth = width;
          }
          curHeight = missingImage.getMeasuredHeight();
        }
        imageViews[i] = missingImage;
      }

      // if we get a taller image/text, force all cells to be that height
      // could also set cell heights on a per-row basis if user feedback requests it.
      if (curHeight > maxCellHeight) {
        maxCellHeight = curHeight;
        for (int j = 0; j < i; j++) {
          imageViews[j].setMinimumHeight(maxCellHeight);
        }
      }
      imageViews[i].setMinimumHeight(maxCellHeight);
    }

    // Read the screen dimensions and fit the grid view to them. It is important that the grid
    // knows how far out it can stretch.

    if (numColumns > 0) {
      // gridview.setNumColumns(numColumns);
      gridview.setNumColumns(GridView.AUTO_FIT);
    } else {
      resizeWidth = maxColumnWidth;
      gridview.setNumColumns(GridView.AUTO_FIT);
    }

    gridview.setColumnWidth(resizeWidth);

    gridview.setPadding(HORIZONTAL_PADDING, VERTICAL_PADDING, HORIZONTAL_PADDING, VERTICAL_PADDING);
    gridview.setHorizontalSpacing(SPACING);
    gridview.setVerticalSpacing(SPACING);
    gridview.setGravity(Gravity.CENTER);
    gridview.setScrollContainer(false);
    gridview.setStretchMode(GridView.NO_STRETCH);

    gridview.setOnItemClickListener(new OnItemClickListener() {
      public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
        if (selected[position]) {
          selected[position] = false;
          if (audioHandlers[position] != null) {
            audioHandlers[position].stopPlaying();
          }
          imageViews[position].setBackgroundColor(Color.WHITE);
          Collect.getInstance().getActivityLogger().logInstanceAction(this, "onItemClick.deselect",
              mItems.get(position).getValue(), mPrompt.getIndex());

        } else {
          selected[position] = true;
          if (audioHandlers[lastClickPosition] != null) {
            audioHandlers[lastClickPosition].stopPlaying();
          }
          imageViews[position].setBackgroundColor(Color.rgb(orangeRedVal, orangeGreenVal,
              orangeBlueVal));
          Collect.getInstance().getActivityLogger().logInstanceAction(this, "onItemClick.select",
              mItems.get(position).getValue(), mPrompt.getIndex());
          if (audioHandlers[position] != null) {
            audioHandlers[position].playAudio(getContext());
          }
          lastClickPosition = position;
        }

      }
    });

    // Fill in answer
    IAnswerData answer = prompt.getAnswerValue();
    Vector<Selection> ve;
    if ((answer == null) || (answer.getValue() == null)) {
      ve = new Vector<>();
    } else {
      ve = (Vector<Selection>) answer.getValue();
    }

    for (int i = 0; i < choices.length; ++i) {

      String value = mItems.get(i).getValue();
      boolean found = false;
      for (Selection s : ve) {
        if (value.equals(s.getValue())) {
          found = true;
          break;
        }
      }

      selected[i] = found;
      if (selected[i]) {
        imageViews[i].setBackgroundColor(Color.rgb(orangeRedVal, orangeGreenVal,
            orangeBlueVal));
      } else {
        imageViews[i].setBackgroundColor(Color.WHITE);
      }
    }

    // Use the custom image adapter and initialize the grid view
    ImageAdapter ia = new ImageAdapter(getContext(), choices);
    gridview.setAdapter(ia);
    final LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
    params.setMarginStart(getResources().getDimensionPixelSize(R.dimen.question_padding_start));
    addView(gridview, params);
  }


  @Override
  public IAnswerData getAnswer() {
    Vector<Selection> vc = new Vector<>();
    for (int i = 0; i < mItems.size(); i++) {
      if (selected[i]) {
        SelectChoice sc = mItems.get(i);
        vc.add(new Selection(sc));
      }
    }

    if (vc.size() == 0) {
      return null;
    } else {
      return new SelectMultiData(vc);
    }
  }


  @Override
  public void clearAnswer() {
    final int itemCount = mItems.size();
    for (int i = 0; i < itemCount; ++i) {
      selected[i] = false;
      imageViews[i].setBackgroundColor(Color.WHITE);
    }

  }


  @Override
  public void setFocus(Context context) {
    // Hide the soft keyboard if it's showing.
    InputMethodManager inputManager =
        (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
    inputManager.hideSoftInputFromWindow(this.getWindowToken(), 0);

  }

  // Custom image adapter. Most of the code is copied from
  // media layout for using a picture.
  private class ImageAdapter extends BaseAdapter {
    private String[] choices;


    public ImageAdapter(Context c, String[] choices) {
      this.choices = choices;
    }


    public int getCount() {
      return choices.length;
    }


    public Object getItem(int position) {
      return null;
    }


    public long getItemId(int position) {
      return 0;
    }


    // create a new ImageView for each item referenced by the Adapter
    public View getView(int position, View convertView, ViewGroup parent) {
      if (position < imageViews.length) {
        return imageViews[position];
      } else {
        return convertView;
      }
    }
  }


  @Override
  public void setOnLongClickListener(OnLongClickListener l) {
    gridview.setOnLongClickListener(l);
  }


  @Override
  public void cancelLongPress() {
    super.cancelLongPress();
    gridview.cancelLongPress();
  }
}
