/*
 * Copyright (C) 2015 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 androidx.leanback.widget;

import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP_PREFIX;

import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.view.inputmethod.EditorInfo;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.TextView.OnEditorActionListener;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RestrictTo;
import androidx.recyclerview.widget.DiffUtil;
import androidx.recyclerview.widget.RecyclerView;
import androidx.recyclerview.widget.RecyclerView.ViewHolder;

import java.util.ArrayList;
import java.util.List;

/**
 * GuidedActionAdapter instantiates views for guided actions, and manages their interactions.
 * Presentation (view creation and state animation) is delegated to a {@link
 * GuidedActionsStylist}, while clients are notified of interactions via
 * {@link GuidedActionAdapter.ClickListener} and {@link GuidedActionAdapter.FocusListener}.
 */
@RestrictTo(LIBRARY_GROUP_PREFIX)
public class GuidedActionAdapter extends RecyclerView.Adapter {
    static final String TAG = "GuidedActionAdapter";
    static final boolean DEBUG = false;

    static final String TAG_EDIT = "EditableAction";
    static final boolean DEBUG_EDIT = false;

    /**
     * Object listening for click events within a {@link GuidedActionAdapter}.
     */
    public interface ClickListener {

        /**
         * Called when the user clicks on an action.
         */
        void onGuidedActionClicked(GuidedAction action);

    }

    /**
     * Object listening for focus events within a {@link GuidedActionAdapter}.
     */
    public interface FocusListener {

        /**
         * Called when the user focuses on an action.
         */
        void onGuidedActionFocused(@NonNull GuidedAction action);
    }

    /**
     * Object listening for edit events within a {@link GuidedActionAdapter}.
     */
    public interface EditListener {

        /**
         * Called when the user exits edit mode on an action.
         */
        void onGuidedActionEditCanceled(@NonNull GuidedAction action);

        /**
         * Called when the user exits edit mode on an action and process confirm button in IME.
         */
        long onGuidedActionEditedAndProceed(@NonNull GuidedAction action);

        /**
         * Called when Ime Open
         */
        void onImeOpen();

        /**
         * Called when Ime Close
         */
        void onImeClose();
    }

    final RecyclerView mRecyclerView;
    private final boolean mIsSubAdapter;
    private final ActionOnKeyListener mActionOnKeyListener;
    private final ActionOnFocusListener mActionOnFocusListener;
    private final ActionEditListener mActionEditListener;
    private final ActionAutofillListener mActionAutofillListener;
    @SuppressWarnings("WeakerAccess") /* synthetic access */
    final List<GuidedAction> mActions;
    private ClickListener mClickListener;
    final GuidedActionsStylist mStylist;
    GuidedActionAdapterGroup mGroup;
    DiffCallback<GuidedAction> mDiffCallback;

    private final View.OnClickListener mOnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (v != null && v.getWindowToken() != null && mRecyclerView.isAttachedToWindow()) {
                GuidedActionsStylist.ViewHolder avh = (GuidedActionsStylist.ViewHolder)
                        mRecyclerView.getChildViewHolder(v);
                GuidedAction action = avh.getAction();
                if (action.hasTextEditable()) {
                    if (DEBUG_EDIT) Log.v(TAG_EDIT, "openIme by click");
                    mGroup.openIme(GuidedActionAdapter.this, avh);
                } else if (action.hasEditableActivatorView()) {
                    if (DEBUG_EDIT) Log.v(TAG_EDIT, "toggle editing mode by click");
                    performOnActionClick(avh);
                } else {
                    handleCheckedActions(avh);
                    if (action.isEnabled() && !action.infoOnly()) {
                        performOnActionClick(avh);
                    }
                }
            }
        }
    };

    /**
     * Constructs a GuidedActionAdapter with the given list of guided actions, the given click and
     * focus listeners, and the given presenter.
     * @param actions The list of guided actions this adapter will manage.
     * @param focusListener The focus listener for items in this adapter.
     * @param presenter The presenter that will manage the display of items in this adapter.
     */
    public GuidedActionAdapter(List<GuidedAction> actions, ClickListener clickListener,
            FocusListener focusListener, GuidedActionsStylist presenter, boolean isSubAdapter) {
        super();
        mActions = actions == null ? new ArrayList<GuidedAction>() :
                new ArrayList<GuidedAction>(actions);
        mClickListener = clickListener;
        mStylist = presenter;
        mActionOnKeyListener = new ActionOnKeyListener();
        mActionOnFocusListener = new ActionOnFocusListener(focusListener);
        mActionEditListener = new ActionEditListener();
        mActionAutofillListener = new ActionAutofillListener();
        mIsSubAdapter = isSubAdapter;
        if (!isSubAdapter) {
            mDiffCallback = GuidedActionDiffCallback.getInstance();
        }
        mRecyclerView = isSubAdapter ? mStylist.getSubActionsGridView() :
                mStylist.getActionsGridView();
    }

    /**
     * Change DiffCallback used in {@link #setActions(List)}. Set to null for firing a
     * general {@link #notifyDataSetChanged()}.
     *
     * @param diffCallback
     */
    public void setDiffCallback(DiffCallback<GuidedAction> diffCallback) {
        mDiffCallback = diffCallback;
    }

    /**
     * Sets the list of actions managed by this adapter. Use {@link #setDiffCallback(DiffCallback)}
     * to change DiffCallback.
     * @param actions The list of actions to be managed.
     */
    public void setActions(final List<GuidedAction> actions) {
        if (!mIsSubAdapter) {
            mStylist.collapseAction(false);
        }
        mActionOnFocusListener.unFocus();
        if (mDiffCallback != null) {
            // temporary variable used for DiffCallback
            final List<GuidedAction> oldActions = new ArrayList<>();
            oldActions.addAll(mActions);

            // update items.
            mActions.clear();
            mActions.addAll(actions);

            DiffUtil.DiffResult diffResult = DiffUtil.calculateDiff(new DiffUtil.Callback() {
                @Override
                public int getOldListSize() {
                    return oldActions.size();
                }

                @Override
                public int getNewListSize() {
                    return mActions.size();
                }

                @Override
                public boolean areItemsTheSame(int oldItemPosition, int newItemPosition) {
                    return mDiffCallback.areItemsTheSame(oldActions.get(oldItemPosition),
                            mActions.get(newItemPosition));
                }

                @Override
                public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
                    return mDiffCallback.areContentsTheSame(oldActions.get(oldItemPosition),
                            mActions.get(newItemPosition));
                }

                @Nullable
                @Override
                public Object getChangePayload(int oldItemPosition, int newItemPosition) {
                    return mDiffCallback.getChangePayload(oldActions.get(oldItemPosition),
                            mActions.get(newItemPosition));
                }
            });

            // dispatch diff result
            diffResult.dispatchUpdatesTo(this);
        } else {
            mActions.clear();
            mActions.addAll(actions);
            notifyDataSetChanged();
        }
    }

    /**
     * Returns the count of actions managed by this adapter.
     * @return The count of actions managed by this adapter.
     */
    public int getCount() {
        return mActions.size();
    }

    /**
     * Returns the GuidedAction at the given position in the managed list.
     * @param position The position of the desired GuidedAction.
     * @return The GuidedAction at the given position.
     */
    public GuidedAction getItem(int position) {
        return mActions.get(position);
    }

    /**
     * Return index of action in array
     * @param action Action to search index.
     * @return Index of Action in array.
     */
    public int indexOf(GuidedAction action) {
        return mActions.indexOf(action);
    }

    /**
     * @return GuidedActionsStylist used to build the actions list UI.
     */
    public GuidedActionsStylist getGuidedActionsStylist() {
        return mStylist;
    }

    /**
     * Sets the click listener for items managed by this adapter.
     * @param clickListener The click listener for this adapter.
     */
    public void setClickListener(ClickListener clickListener) {
        mClickListener = clickListener;
    }

    /**
     * Sets the focus listener for items managed by this adapter.
     * @param focusListener The focus listener for this adapter.
     */
    public void setFocusListener(FocusListener focusListener) {
        mActionOnFocusListener.setFocusListener(focusListener);
    }

    /**
     * Used for serialization only.
     */
    @RestrictTo(LIBRARY_GROUP_PREFIX)
    public List<GuidedAction> getActions() {
        return new ArrayList<GuidedAction>(mActions);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int getItemViewType(int position) {
        return mStylist.getItemViewType(mActions.get(position));
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        GuidedActionsStylist.ViewHolder vh = mStylist.onCreateViewHolder(parent, viewType);
        View v = vh.itemView;
        v.setOnKeyListener(mActionOnKeyListener);
        v.setOnClickListener(mOnClickListener);
        v.setOnFocusChangeListener(mActionOnFocusListener);

        setupListeners(vh.getEditableTitleView());
        setupListeners(vh.getEditableDescriptionView());

        return vh;
    }

    private void setupListeners(EditText edit) {
        if (edit != null) {
            edit.setPrivateImeOptions("escapeNorth");
            edit.setOnEditorActionListener(mActionEditListener);
            if (edit instanceof ImeKeyMonitor) {
                ImeKeyMonitor monitor = (ImeKeyMonitor)edit;
                monitor.setImeKeyListener(mActionEditListener);
            }
            if (edit instanceof GuidedActionAutofillSupport) {
                ((GuidedActionAutofillSupport) edit).setOnAutofillListener(mActionAutofillListener);
            }
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        if (position >= mActions.size()) {
            return;
        }
        final GuidedActionsStylist.ViewHolder avh = (GuidedActionsStylist.ViewHolder)holder;
        GuidedAction action = mActions.get(position);
        mStylist.onBindViewHolder(avh, action);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int getItemCount() {
        return mActions.size();
    }

    private class ActionOnFocusListener implements View.OnFocusChangeListener {

        private FocusListener mFocusListener;
        private View mSelectedView;

        ActionOnFocusListener(FocusListener focusListener) {
            mFocusListener = focusListener;
        }

        public void setFocusListener(FocusListener focusListener) {
            mFocusListener = focusListener;
        }

        public void unFocus() {
            if (mSelectedView != null && mRecyclerView.isAttachedToWindow()) {
                ViewHolder vh = mRecyclerView.getChildViewHolder(mSelectedView);
                if (vh != null) {
                    GuidedActionsStylist.ViewHolder avh = (GuidedActionsStylist.ViewHolder)vh;
                    mStylist.onAnimateItemFocused(avh, false);
                } else {
                    Log.w(TAG, "RecyclerView returned null view holder",
                            new Throwable());
                }
            }
        }

        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (!mRecyclerView.isAttachedToWindow()) {
                return;
            }
            GuidedActionsStylist.ViewHolder avh = (GuidedActionsStylist.ViewHolder)
                    mRecyclerView.getChildViewHolder(v);
            if (hasFocus) {
                mSelectedView = v;
                if (mFocusListener != null) {
                    // We still call onGuidedActionFocused so that listeners can clear
                    // state if they want.
                    mFocusListener.onGuidedActionFocused(avh.getAction());
                }
            } else {
                if (mSelectedView == v) {
                    mStylist.onAnimateItemPressedCancelled(avh);
                    mSelectedView = null;
                }
            }
            mStylist.onAnimateItemFocused(avh, hasFocus);
        }
    }

    public GuidedActionsStylist.ViewHolder findSubChildViewHolder(View v) {
        if (!mRecyclerView.isAttachedToWindow()) {
            return null;
        }
        GuidedActionsStylist.ViewHolder result = null;
        ViewParent parent = v.getParent();
        while (parent != mRecyclerView && parent != null && v != null) {
            v = (View)parent;
            parent = parent.getParent();
        }
        if (parent != null && v != null) {
            result = (GuidedActionsStylist.ViewHolder) mRecyclerView.getChildViewHolder(v);
        }
        return result;
    }

    public void handleCheckedActions(GuidedActionsStylist.ViewHolder avh) {
        GuidedAction action = avh.getAction();
        int actionCheckSetId = action.getCheckSetId();
        if (mRecyclerView.isAttachedToWindow() && actionCheckSetId != GuidedAction.NO_CHECK_SET) {
            // Find any actions that are checked and are in the same group
            // as the selected action. Fade their checkmarks out.
            if (actionCheckSetId != GuidedAction.CHECKBOX_CHECK_SET_ID) {
                for (int i = 0, size = mActions.size(); i < size; i++) {
                    GuidedAction a = mActions.get(i);
                    if (a != action && a.getCheckSetId() == actionCheckSetId && a.isChecked()) {
                        a.setChecked(false);
                        GuidedActionsStylist.ViewHolder vh = (GuidedActionsStylist.ViewHolder)
                                mRecyclerView.findViewHolderForPosition(i);
                        if (vh != null) {
                            mStylist.onAnimateItemChecked(vh, false);
                        }
                    }
                }
            }

            // If we we'ren't already checked, fade our checkmark in.
            if (!action.isChecked()) {
                action.setChecked(true);
                mStylist.onAnimateItemChecked(avh, true);
            } else {
                if (actionCheckSetId == GuidedAction.CHECKBOX_CHECK_SET_ID) {
                    action.setChecked(false);
                    mStylist.onAnimateItemChecked(avh, false);
                }
            }
        }
    }

    public void performOnActionClick(GuidedActionsStylist.ViewHolder avh) {
        if (mClickListener != null) {
            mClickListener.onGuidedActionClicked(avh.getAction());
        }
    }

    private class ActionOnKeyListener implements View.OnKeyListener {

        private boolean mKeyPressed = false;

        ActionOnKeyListener() {
        }

        /**
         * Now only handles KEYCODE_ENTER and KEYCODE_NUMPAD_ENTER key event.
         */
        @Override
        public boolean onKey(View v, int keyCode, KeyEvent event) {
            if (v == null || event == null || !mRecyclerView.isAttachedToWindow()) {
                return false;
            }
            boolean handled = false;
            switch (keyCode) {
                case KeyEvent.KEYCODE_DPAD_CENTER:
                case KeyEvent.KEYCODE_NUMPAD_ENTER:
                case KeyEvent.KEYCODE_BUTTON_X:
                case KeyEvent.KEYCODE_BUTTON_Y:
                case KeyEvent.KEYCODE_ENTER:

                    GuidedActionsStylist.ViewHolder avh = (GuidedActionsStylist.ViewHolder)
                            mRecyclerView.getChildViewHolder(v);
                    GuidedAction action = avh.getAction();

                    if (!action.isEnabled() || action.infoOnly()) {
                        if (event.getAction() == KeyEvent.ACTION_DOWN) {
                            // TODO: requires API 19
                            //playSound(v, AudioManager.FX_KEYPRESS_INVALID);
                        }
                        return true;
                    }

                    switch (event.getAction()) {
                        case KeyEvent.ACTION_DOWN:
                            if (DEBUG) {
                                Log.d(TAG, "Enter Key down");
                            }
                            if (!mKeyPressed) {
                                mKeyPressed = true;
                                mStylist.onAnimateItemPressed(avh, mKeyPressed);
                            }
                            break;
                        case KeyEvent.ACTION_UP:
                            if (DEBUG) {
                                Log.d(TAG, "Enter Key up");
                            }
                            // Sometimes we are losing ACTION_DOWN for the first ENTER after pressed
                            // Escape in IME.
                            if (mKeyPressed) {
                                mKeyPressed = false;
                                mStylist.onAnimateItemPressed(avh, mKeyPressed);
                            }
                            break;
                        default:
                            break;
                    }
                    break;
                default:
                    break;
            }
            return handled;
        }

    }

    private class ActionEditListener implements OnEditorActionListener,
            ImeKeyMonitor.ImeKeyListener {

        ActionEditListener() {
        }

        @Override
        public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
            if (DEBUG_EDIT) Log.v(TAG_EDIT, "IME action: " + actionId);
            boolean handled = false;
            if (actionId == EditorInfo.IME_ACTION_NEXT
                    || actionId == EditorInfo.IME_ACTION_DONE) {
                mGroup.fillAndGoNext(GuidedActionAdapter.this, v);
                handled = true;
            } else if (actionId == EditorInfo.IME_ACTION_NONE) {
                if (DEBUG_EDIT) Log.v(TAG_EDIT, "closeIme escape north");
                // Escape north handling: stay on current item, but close editor
                handled = true;
                mGroup.fillAndStay(GuidedActionAdapter.this, v);
            }
            return handled;
        }

        @Override
        public boolean onKeyPreIme(EditText editText, int keyCode, KeyEvent event) {
            if (DEBUG_EDIT) Log.v(TAG_EDIT, "IME key: " + keyCode);
            if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_UP) {
                mGroup.fillAndStay(GuidedActionAdapter.this, editText);
                return true;
            } else if (keyCode == KeyEvent.KEYCODE_ENTER
                    && event.getAction() == KeyEvent.ACTION_UP) {
                mGroup.fillAndGoNext(GuidedActionAdapter.this, editText);
                return true;
            }
            return false;
        }
    }

    private class ActionAutofillListener implements GuidedActionAutofillSupport.OnAutofillListener {
        ActionAutofillListener() {
        }

        @Override
        public void onAutofill(View view) {
            mGroup.fillAndGoNext(GuidedActionAdapter.this, (EditText) view);
        }
    }
}