QuestionsActivity.java

/*
    Copyright (C) 2014 Prasanna Thirumalai
    
    This file is part of StackX.

    StackX is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    StackX is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with StackX.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.prasanna.android.stacknetwork;

import java.util.HashMap;

import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.app.SearchManager;
import android.content.Intent;
import android.database.SQLException;
import android.os.Bundle;
import android.provider.SearchRecentSuggestions;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

import com.prasanna.android.provider.RecentQueriesProvider;
import com.prasanna.android.stacknetwork.fragment.QuestionListFragment;
import com.prasanna.android.stacknetwork.fragment.TagListFragment;
import com.prasanna.android.stacknetwork.fragment.TagListFragment.OnTagSelectListener;
import com.prasanna.android.stacknetwork.model.SearchCriteria;
import com.prasanna.android.stacknetwork.service.QuestionsIntentService;
import com.prasanna.android.stacknetwork.sqlite.TagDAO;
import com.prasanna.android.stacknetwork.utils.DbRequestThreadExecutor;
import com.prasanna.android.stacknetwork.utils.OperatingSite;
import com.prasanna.android.stacknetwork.utils.SharedPreferencesUtil;
import com.prasanna.android.stacknetwork.utils.StackUri.Sort;
import com.prasanna.android.stacknetwork.utils.StringConstants;

public class QuestionsActivity extends AbstractUserActionBarActivity implements OnTagSelectListener {
  private static final String TAB_TITLE_ACTIVE = "Active";
  private static final String TAB_TITLE_NEW = "New";
  private static final String TAB_TITLE_FEATURED = "Featured";
  private static final String TAB_TITLE_MOST_VOTED = "Most Voted";
  private static final String TAB_TITLE_FAQ = "FAQ";
  private static final String LAST_SELECTED_TAB = "last_selected_tab";

  private static QuestionsActivity self;

  private boolean showTagsFragment = false;
  private TagListFragment tagListFragment;
  private String intentAction;
  private String tag;
  private int action;

  public static QuestionListFragment getFragment(String fragmentTag) {
    if (self != null) return (QuestionListFragment) self.getFragmentManager().findFragmentByTag(fragmentTag);
    else return null;
  }

  public class TabListener implements ActionBar.TabListener {
    private final QuestionListFragment fragment;

    public TabListener(QuestionListFragment fragment) {
      this.fragment = fragment;
    }

    public void onTabSelected(Tab tab, FragmentTransaction ft) {
      Fragment existingFragment = getFragmentManager().findFragmentByTag(fragment.fragmentTag);
      ft.setCustomAnimations(R.anim.slide_in_left, 0);

      if (existingFragment == null) ft.add(R.id.fragmentContainer, fragment, fragment.fragmentTag);
      else ft.attach(existingFragment);
    }

    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
      ft.setCustomAnimations(0, R.anim.slide_out_left);
      ft.remove(fragment);
    }

    public void onTabReselected(Tab tab, FragmentTransaction ft) {
    }
  }

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    self = this;

    setContentView(R.layout.fragment_container);

    if (savedInstanceState != null) {
      action = savedInstanceState.getInt(StringConstants.ACTION, 0);

      if (action != 0) {
        if (action == QuestionsIntentService.GET_QUESTIONS_FOR_TAG) showLastTagQuestionListFragment(savedInstanceState);
        else showFrontPageForSite();

        int lastSelectedTab = savedInstanceState.getInt(LAST_SELECTED_TAB, 0);
        if (lastSelectedTab > 0) getActionBar().setSelectedNavigationItem(lastSelectedTab);
      }
    }
  }

  private void showFrontPageForSite() {
    showTagsFragment = true;
    getActionBar().setDisplayHomeAsUpEnabled(true);
    setupActionBarTabs(QuestionsIntentService.GET_FRONT_PAGE, OperatingSite.getSite().name, true);
  }

  private void showLastTagQuestionListFragment(Bundle savedInstanceState) {
    showTagsFragment = true;
    getActionBar().setDisplayHomeAsUpEnabled(true);
    setupActionBarTabs(action, savedInstanceState.getString(StringConstants.TAG), false);
  }

  private void setupActionBarTabs(int action, String tag, boolean frontPage) {
    getActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    this.action = action;
    this.tag = tag;

    createTab(TAB_TITLE_ACTIVE, QuestionListFragment.newFragment(action, tag, Sort.ACTIVITY), true);
    createTab(TAB_TITLE_NEW, QuestionListFragment.newFragment(action, tag, Sort.CREATION), false);
    createTab(TAB_TITLE_FEATURED, QuestionListFragment.newFragment(QuestionsIntentService.GET_FEATURED, tag), false);
    createTab(TAB_TITLE_MOST_VOTED, QuestionListFragment.newFragment(action, tag, Sort.VOTES), false);

    if (!frontPage) {
      createTab(TAB_TITLE_FAQ, QuestionListFragment.newFragment(QuestionsIntentService.GET_FAQ_FOR_TAG, tag, null),
          false);
    } else {
      HashMap<String, SearchCriteria> customTabs =
          DbRequestThreadExecutor.getSearchesMarkedForTab(getApplicationContext(),
              OperatingSite.getSite().apiSiteParameter);

      if (customTabs != null) {
        for (String key : customTabs.keySet())
          createTab(key, QuestionListFragment.newFragment(key, customTabs.get(key)), false);
      }
    }
  }

  private void createTab(String title, QuestionListFragment fragment, boolean setSelected) {
    Tab tab = getActionBar().newTab();
    tab.setText(title).setTabListener(new TabListener(fragment));
    getActionBar().addTab(tab, setSelected);
  }

  @Override
  public void onSaveInstanceState(Bundle outState) {
    removeTagListFragment();

    if (getActionBar().getNavigationMode() == ActionBar.NAVIGATION_MODE_TABS)
      outState.putInt(LAST_SELECTED_TAB, getActionBar().getSelectedNavigationIndex());

    outState.putInt(StringConstants.ACTION, action);
    outState.putString(StringConstants.TAG, tag);

    super.onSaveInstanceState(outState);
  }

  private void removeTagListFragment() {
    if (tagListFragment != null) {
      FragmentTransaction ft = getFragmentManager().beginTransaction();
      ft.remove(tagListFragment);
      ft.commit();
      tagListFragment = null;
    }
  }

  @Override
  public void onResume() {
    super.onResume();

    if (getActionBar().getTabCount() == 0) showFragmentForIntentAction();
    else {
      Fragment fragment = getFragmentManager().findFragmentById(R.id.fragmentContainer);
      if (fragment != null) {
        FragmentTransaction ft = getFragmentManager().beginTransaction();
        ft.show(fragment);
        ft.commit();
      } else {
        if (getIntent().getAction() == null || StringConstants.TAG.equals(getIntent().getAction())) {
          getActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
          getActionBar().setDisplayHomeAsUpEnabled(true);
          getActionBar().setSelectedNavigationItem(0);
        }
      }
    }
  }

  private void showFragmentForIntentAction() {
    intentAction = getIntent().getAction();

    if (Intent.ACTION_SEARCH.equals(intentAction)) showSearchFragment();
    else if (StringConstants.SIMILAR.equals(intentAction)) showSimilarQuestionListFragment();
    else if (StringConstants.RELATED.equals(intentAction)) showRelatedQuestionListFragment();
    else if (StringConstants.TAG.equals(intentAction)) showTagQuestionListFragment();
    else showFrontPageForSite();
  }

  private void showSearchFragment() {
    String query = getIntent().getStringExtra(SearchManager.QUERY);
    saveSearchQuery(query);

    String fragmentTag = "search -" + query;
    QuestionListFragment questionListFragment = getFragment(fragmentTag);

    if (questionListFragment == null)
      questionListFragment = QuestionListFragment.newFragment(QuestionsIntentService.SEARCH, query, null);

    replaceFragment(questionListFragment, fragmentTag, false);
  }

  private void saveSearchQuery(String query) {
    SearchRecentSuggestions suggestions =
        new SearchRecentSuggestions(this, RecentQueriesProvider.AUTHORITY, RecentQueriesProvider.MODE);
    suggestions.saveRecentQuery(query, null);
  }

  private void showSimilarQuestionListFragment() {
    String title = getIntent().getStringExtra(StringConstants.TITLE);
    String fragmentTag = QuestionsIntentService.GET_SIMILAR + "-" + title.hashCode();
    setActionBarTitle(getString(R.string.similar) + " to " + title);

    QuestionListFragment questionListFragment = getFragment(fragmentTag);
    if (questionListFragment == null) {
      questionListFragment = QuestionListFragment.newFragment(QuestionsIntentService.GET_SIMILAR, fragmentTag);
      questionListFragment.getBundle().putString(StringConstants.TITLE, title);
      replaceFragment(questionListFragment, fragmentTag, false);
    }
  }

  private void showRelatedQuestionListFragment() {
    long questionId = getIntent().getLongExtra(StringConstants.QUESTION_ID, 0);
    String fragmentTag = QuestionsIntentService.GET_RELATED + "-" + questionId;

    QuestionListFragment questionListFragment = getFragment(fragmentTag);
    if (questionListFragment == null) {
      questionListFragment = QuestionListFragment.newFragment(QuestionsIntentService.GET_RELATED, fragmentTag);
      questionListFragment.getBundle().putLong(StringConstants.QUESTION_ID, questionId);
      replaceFragment(questionListFragment, fragmentTag, false);
    }
  }

  private void showTagQuestionListFragment() {
    String tag = getIntent().getStringExtra(StringConstants.TAG);
    setupActionBarTabs(QuestionsIntentService.GET_QUESTIONS_FOR_TAG, tag, false);
  }

  @Override
  public void onBackPressed() {
    if (!hideTagFragmentIfShown()) super.onBackPressed();
  }

  private boolean hideTagFragmentIfShown() {
    Fragment currentFragment = getFragmentManager().findFragmentById(R.id.fragmentContainer);

    if (currentFragment instanceof TagListFragment) {
      hideTagFragment();
      toggleDisplayForTags(false);
      return true;
    }

    return false;
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    boolean ret = super.onCreateOptionsMenu(menu);

    if (menu != null && intentAction != null && StringConstants.TAG.equals(intentAction))
      menu.findItem(R.id.menu_new_label).setVisible(true);

    return ret;
  }

  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
    if (intentAction != null && StringConstants.TAG.equals(intentAction)) {
      if (item.getItemId() == R.id.menu_new_label) {
        insertTagToDb();
        return true;
      }
    }

    return super.onOptionsItemSelected(item);
  }

  private void insertTagToDb() {
    TagDAO tagDAO = new TagDAO(this);
    String tagLabel = getIntent().getStringExtra(StringConstants.TAG);
    try {
      tagDAO.open();
      tagDAO.insert(OperatingSite.getSite().apiSiteParameter, tagLabel, true);

      Toast.makeText(this, tagLabel + " added to your tags", Toast.LENGTH_LONG).show();
      SharedPreferencesUtil.setBoolean(this, TagListFragment.TAGS_DIRTY, true);
    } catch (SQLException e) {
      Toast.makeText(this, "Failed to add " + tagLabel + " to your tags", Toast.LENGTH_LONG).show();
    } finally {
      tagDAO.close();
    }
  }

  @Override
  public void refresh() {
    QuestionListFragment questionsFragment =
        (QuestionListFragment) getFragmentManager().findFragmentById(R.id.fragmentContainer);
    questionsFragment.refresh();
  }

  @Override
  protected boolean shouldSearchViewBeEnabled() {
    return true;
  }

  @Override
  protected boolean onActionBarHomeButtonClick(MenuItem menuItem) {
    if (showTagsFragment && menuItem.getItemId() == android.R.id.home) {
      tagListFragment = (TagListFragment) getFragmentManager().findFragmentByTag(StringConstants.TAGS);

      if (tagListFragment == null) {
        tagListFragment = TagListFragment.newFragment(this);
        addAndHideFragment(tagListFragment, StringConstants.TAGS);
      } else tagListFragment.setOnTagSelectListener(this);

      toggleDisplayForTags(true);
      showTagFragment();
      return true;
    }

    return super.onActionBarHomeButtonClick(menuItem);
  }

  private void toggleDisplayForTags(boolean forTags) {
    getActionBar().setDisplayHomeAsUpEnabled(!forTags);

    if (forTags) {
      getActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
      setActionBarTitle(StringConstants.TAGS);
    } else getActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    actionBarMenu.findItem(R.id.menu_search).setVisible(!forTags);
    actionBarMenu.findItem(R.id.menu_refresh).setVisible(!forTags);
  }

  @Override
  public void onFrontPageSelected() {
    hideTagFragment();
    setupTabsForTag(QuestionsIntentService.GET_FRONT_PAGE, OperatingSite.getSite().name, true);
  }

  @Override
  public void onTagSelected(String tag) {
    hideTagFragment();
    setupTabsForTag(QuestionsIntentService.GET_QUESTIONS_FOR_TAG, tag, false);
  }

  private void addAndHideFragment(TagListFragment fragment, String fragmentTag) {
    FragmentTransaction ft = getFragmentManager().beginTransaction();
    ft.add(R.id.fragmentContainer, fragment, fragmentTag);
    ft.hide(fragment);
    ft.commit();
  }

  private void setupTabsForTag(int action, String newTag, boolean frontPage) {
    toggleDisplayForTags(false);

    if (tag == null || !tag.equals(newTag)) {
      getActionBar().removeAllTabs();
      setupActionBarTabs(action, newTag, frontPage);
    }
  }

  private void showTagFragment() {
    FragmentTransaction ft = getFragmentManager().beginTransaction();
    ft.setCustomAnimations(R.anim.slide_in_left, 0);
    ft.show(tagListFragment);
    ft.commit();
  }

  private void hideTagFragment() {
    FragmentTransaction ft = getFragmentManager().beginTransaction();
    ft.setCustomAnimations(0, R.anim.slide_out_left);
    ft.hide(tagListFragment);
    ft.commit();
    getFragmentManager().executePendingTransactions();
  }

  private void replaceFragment(Fragment fragment, String fragmentTag, boolean addToBackStack) {
    FragmentTransaction ft = getFragmentManager().beginTransaction();
    ft.setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out);
    ft.replace(R.id.fragmentContainer, fragment, fragmentTag);
    if (addToBackStack) ft.addToBackStack(fragmentTag);
    ft.commit();
  }
}