/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * 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 com.android.contacts.activities;

import com.android.contacts.R;
import com.android.contacts.activities.ActionBarAdapter.Listener.Action;
import com.android.contacts.list.ContactsRequest;

import android.app.ActionBar;
import android.app.ActionBar.LayoutParams;
import android.app.ActionBar.Tab;
import android.app.FragmentTransaction;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.SearchView;
import android.widget.SearchView.OnCloseListener;
import android.widget.SearchView.OnQueryTextListener;

/**
 * Adapter for the action bar at the top of the Contacts activity.
 */
public class ActionBarAdapter implements OnQueryTextListener, OnCloseListener {

    public interface Listener {
        public enum Action {
            CHANGE_SEARCH_QUERY, START_SEARCH_MODE, STOP_SEARCH_MODE
        }

        void onAction(Action action);

        /**
         * Called when the user selects a tab.  The new tab can be obtained using
         * {@link #getCurrentTab}.
         */
        void onSelectedTabChanged();
    }

    private static final String EXTRA_KEY_SEARCH_MODE = "navBar.searchMode";
    private static final String EXTRA_KEY_QUERY = "navBar.query";
    private static final String EXTRA_KEY_SELECTED_TAB = "navBar.selectedTab";

    private static final String PERSISTENT_LAST_TAB = "actionBarAdapter.lastTab";

    private boolean mSearchMode;
    private String mQueryString;

    private SearchView mSearchView;

    private final Context mContext;
    private final SharedPreferences mPrefs;

    private Listener mListener;

    private final ActionBar mActionBar;
    private final MyTabListener mTabListener = new MyTabListener();

    private boolean mShowHomeIcon;
    private boolean mShowTabsAsText;

    public enum TabState {
        GROUPS,
        ALL,
        FAVORITES;

        public static TabState fromInt(int value) {
            if (GROUPS.ordinal() == value) {
                return GROUPS;
            }
            if (ALL.ordinal() == value) {
                return ALL;
            }
            if (FAVORITES.ordinal() == value) {
                return FAVORITES;
            }
            throw new IllegalArgumentException("Invalid value: " + value);
        }
    }

    private static final TabState DEFAULT_TAB = TabState.ALL;
    private TabState mCurrentTab = DEFAULT_TAB;

    public ActionBarAdapter(Context context, Listener listener, ActionBar actionBar,
            boolean isUsingTwoPanes) {
        mContext = context;
        mListener = listener;
        mActionBar = actionBar;
        mPrefs = PreferenceManager.getDefaultSharedPreferences(mContext);

        mShowHomeIcon = mContext.getResources().getBoolean(R.bool.show_home_icon);

        // On wide screens, show the tabs as text (instead of icons)
        mShowTabsAsText = isUsingTwoPanes;

        // Set up search view.
        View customSearchView = LayoutInflater.from(mActionBar.getThemedContext()).inflate(
                R.layout.custom_action_bar, null);
        int searchViewWidth = mContext.getResources().getDimensionPixelSize(
                R.dimen.search_view_width);
        if (searchViewWidth == 0) {
            searchViewWidth = LayoutParams.MATCH_PARENT;
        }
        LayoutParams layoutParams = new LayoutParams(searchViewWidth, LayoutParams.WRAP_CONTENT);
        mSearchView = (SearchView) customSearchView.findViewById(R.id.search_view);
        // Since the {@link SearchView} in this app is "click-to-expand", set the below mode on the
        // {@link SearchView} so that the magnifying glass icon appears inside the editable text
        // field. (In the "click-to-expand" search pattern, the user must explicitly expand the
        // search field and already knows a search is being conducted, so the icon is redundant
        // and can go away once the user starts typing.)
        mSearchView.setIconifiedByDefault(true);
        mSearchView.setQueryHint(mContext.getString(R.string.hint_findContacts));
        mSearchView.setOnQueryTextListener(this);
        mSearchView.setOnCloseListener(this);
        mSearchView.setQuery(mQueryString, false);
        mActionBar.setCustomView(customSearchView, layoutParams);

        // Set up tabs
        addTab(TabState.GROUPS, R.drawable.ic_tab_groups, R.string.contactsGroupsLabel);
        addTab(TabState.ALL, R.drawable.ic_tab_all, R.string.contactsAllLabel);
        addTab(TabState.FAVORITES, R.drawable.ic_tab_starred, R.string.contactsFavoritesLabel);
    }

    public void initialize(Bundle savedState, ContactsRequest request) {
        if (savedState == null) {
            mSearchMode = request.isSearchMode();
            mQueryString = request.getQueryString();
            mCurrentTab = loadLastTabPreference();
        } else {
            mSearchMode = savedState.getBoolean(EXTRA_KEY_SEARCH_MODE);
            mQueryString = savedState.getString(EXTRA_KEY_QUERY);

            // Just set to the field here.  The listener will be notified by update().
            mCurrentTab = TabState.fromInt(savedState.getInt(EXTRA_KEY_SELECTED_TAB));
        }
        // Show tabs or the expanded {@link SearchView}, depending on whether or not we are in
        // search mode.
        update();
        // Expanding the {@link SearchView} clears the query, so set the query from the
        // {@link ContactsRequest} after it has been expanded, if applicable.
        if (mSearchMode && !TextUtils.isEmpty(mQueryString)) {
            setQueryString(mQueryString);
        }
    }

    public void setListener(Listener listener) {
        mListener = listener;
    }

    private void addTab(TabState tabState, int icon, int description) {
        final Tab tab = mActionBar.newTab();
        tab.setTag(tabState);
        tab.setTabListener(mTabListener);
        if (mShowTabsAsText) {
            tab.setText(description);
        } else {
            tab.setIcon(icon);
            tab.setContentDescription(description);
        }
        mActionBar.addTab(tab);
    }

    private class MyTabListener implements ActionBar.TabListener {
        /**
         * If true, it won't call {@link #setCurrentTab} in {@link #onTabSelected}.
         * This flag is used when we want to programmatically update the current tab without
         * {@link #onTabSelected} getting called.
         */
        public boolean mIgnoreTabSelected;

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

        @Override public void onTabSelected(Tab tab, FragmentTransaction ft) {
            if (!mIgnoreTabSelected) {
                setCurrentTab((TabState)tab.getTag());
            }
        }
    }

    /**
     * Change the current tab, and notify the listener.
     */
    public void setCurrentTab(TabState tab) {
        setCurrentTab(tab, true);
    }

    /**
     * Change the current tab
     */
    public void setCurrentTab(TabState tab, boolean notifyListener) {
        if (tab == null) throw new NullPointerException();
        if (tab == mCurrentTab) {
            return;
        }
        mCurrentTab = tab;

        int index = mCurrentTab.ordinal();
        if ((mActionBar.getNavigationMode() == ActionBar.NAVIGATION_MODE_TABS)
                && (index != mActionBar.getSelectedNavigationIndex())) {
            mActionBar.setSelectedNavigationItem(index);
        }

        if (notifyListener && mListener != null) mListener.onSelectedTabChanged();
        saveLastTabPreference(mCurrentTab);
    }

    public TabState getCurrentTab() {
        return mCurrentTab;
    }

    /**
     * @return Whether in search mode, i.e. if the search view is visible/expanded.
     *
     * Note even if the action bar is in search mode, if the query is empty, the search fragment
     * will not be in search mode.
     */
    public boolean isSearchMode() {
        return mSearchMode;
    }

    public void setSearchMode(boolean flag) {
        if (mSearchMode != flag) {
            mSearchMode = flag;
            update();
            if (mSearchView == null) {
                return;
            }
            if (mSearchMode) {
                setFocusOnSearchView();
            } else {
                mSearchView.setQuery(null, false);
            }
        }
    }

    public String getQueryString() {
        return mSearchMode ? mQueryString : null;
    }

    public void setQueryString(String query) {
        mQueryString = query;
        if (mSearchView != null) {
            mSearchView.setQuery(query, false);
        }
    }

    /** @return true if the "UP" icon is showing. */
    public boolean isUpShowing() {
        return mSearchMode; // Only shown on the search mode.
    }

    private void updateDisplayOptions() {
        // All the flags we may change in this method.
        final int MASK = ActionBar.DISPLAY_SHOW_TITLE | ActionBar.DISPLAY_SHOW_HOME
                | ActionBar.DISPLAY_HOME_AS_UP | ActionBar.DISPLAY_SHOW_CUSTOM;

        // The current flags set to the action bar.  (only the ones that we may change here)
        final int current = mActionBar.getDisplayOptions() & MASK;

        // Build the new flags...
        int newFlags = 0;
        newFlags |= ActionBar.DISPLAY_SHOW_TITLE;
        if (mShowHomeIcon) {
            newFlags |= ActionBar.DISPLAY_SHOW_HOME;
        }
        if (mSearchMode) {
            newFlags |= ActionBar.DISPLAY_SHOW_HOME;
            newFlags |= ActionBar.DISPLAY_HOME_AS_UP;
            newFlags |= ActionBar.DISPLAY_SHOW_CUSTOM;
        }
        mActionBar.setHomeButtonEnabled(mSearchMode);

        if (current != newFlags) {
            // Pass the mask here to preserve other flags that we're not interested here.
            mActionBar.setDisplayOptions(newFlags, MASK);
        }
    }

    private void update() {
        if (mSearchMode) {
            setFocusOnSearchView();
            // Since we have the {@link SearchView} in a custom action bar, we must manually handle
            // expanding the {@link SearchView} when a search is initiated. Note that a side effect
            // of this method is that the {@link SearchView} query text is set to empty string.
            mSearchView.onActionViewExpanded();
            if (mActionBar.getNavigationMode() != ActionBar.NAVIGATION_MODE_STANDARD) {
                mActionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
            }
            if (mListener != null) {
                mListener.onAction(Action.START_SEARCH_MODE);
            }
        } else {
            if (mActionBar.getNavigationMode() != ActionBar.NAVIGATION_MODE_TABS) {
                // setNavigationMode will trigger onTabSelected() with the tab which was previously
                // selected.
                // The issue is that when we're first switching to the tab navigation mode after
                // screen orientation changes, onTabSelected() will get called with the first tab
                // (i.e. favorite), which would results in mCurrentTab getting set to FAVORITES and
                // we'd lose restored tab.
                // So let's just disable the callback here temporarily.  We'll notify the listener
                // after this anyway.
                mTabListener.mIgnoreTabSelected = true;
                mActionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
                mActionBar.setSelectedNavigationItem(mCurrentTab.ordinal());
                mTabListener.mIgnoreTabSelected = false;
            }
            mActionBar.setTitle(null);
            // Since we have the {@link SearchView} in a custom action bar, we must manually handle
            // collapsing the {@link SearchView} when search mode is exited.
            mSearchView.onActionViewCollapsed();
            if (mListener != null) {
                mListener.onAction(Action.STOP_SEARCH_MODE);
                mListener.onSelectedTabChanged();
            }
        }
        updateDisplayOptions();
    }

    @Override
    public boolean onQueryTextChange(String queryString) {
        // TODO: Clean up SearchView code because it keeps setting the SearchView query,
        // invoking onQueryChanged, setting up the fragment again, invalidating the options menu,
        // storing the SearchView again, and etc... unless we add in the early return statements.
        if (queryString.equals(mQueryString)) {
            return false;
        }
        mQueryString = queryString;
        if (!mSearchMode) {
            if (!TextUtils.isEmpty(queryString)) {
                setSearchMode(true);
            }
        } else if (mListener != null) {
            mListener.onAction(Action.CHANGE_SEARCH_QUERY);
        }

        return true;
    }

    @Override
    public boolean onQueryTextSubmit(String query) {
        // When the search is "committed" by the user, then hide the keyboard so the user can
        // more easily browse the list of results.
        if (mSearchView != null) {
            InputMethodManager imm = (InputMethodManager) mContext.getSystemService(
                    Context.INPUT_METHOD_SERVICE);
            if (imm != null) {
                imm.hideSoftInputFromWindow(mSearchView.getWindowToken(), 0);
            }
            mSearchView.clearFocus();
        }
        return true;
    }

    @Override
    public boolean onClose() {
        setSearchMode(false);
        return false;
    }

    public void onSaveInstanceState(Bundle outState) {
        outState.putBoolean(EXTRA_KEY_SEARCH_MODE, mSearchMode);
        outState.putString(EXTRA_KEY_QUERY, mQueryString);
        outState.putInt(EXTRA_KEY_SELECTED_TAB, mCurrentTab.ordinal());
    }

    /**
     * Clears the focus from the {@link SearchView} if we are in search mode.
     * This will suppress the IME if it is visible.
     */
    public void clearFocusOnSearchView() {
        if (isSearchMode()) {
            if (mSearchView != null) {
                mSearchView.clearFocus();
            }
        }
    }

    private void setFocusOnSearchView() {
        mSearchView.requestFocus();
        mSearchView.setIconified(false); // Workaround for the "IME not popping up" issue.
    }

    private void saveLastTabPreference(TabState tab) {
        mPrefs.edit().putInt(PERSISTENT_LAST_TAB, tab.ordinal()).apply();
    }

    private TabState loadLastTabPreference() {
        try {
            return TabState.fromInt(mPrefs.getInt(PERSISTENT_LAST_TAB, DEFAULT_TAB.ordinal()));
        } catch (IllegalArgumentException e) {
            // Preference is corrupt?
            return DEFAULT_TAB;
        }
    }
}