/*
 * Copyright (C) 2016 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 android.text.style;

import static android.view.accessibility.AccessibilityNodeInfo.ACTION_ARGUMENT_ACCESSIBLE_CLICKABLE_SPAN;
import static android.view.accessibility.AccessibilityNodeInfo.UNDEFINED_CONNECTION_ID;
import static android.view.accessibility.AccessibilityNodeInfo.UNDEFINED_NODE_ID;
import static android.view.accessibility.AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;

import android.os.Bundle;
import android.os.Parcel;
import android.os.Parcelable;
import android.text.ParcelableSpan;
import android.text.Spanned;
import android.text.TextUtils;
import android.view.View;
import android.view.accessibility.AccessibilityInteractionClient;
import android.view.accessibility.AccessibilityNodeInfo;

import com.android.internal.R;

ClickableSpan cannot be parceled, but accessibility services need to be able to cause their callback handlers to be called. This class serves as a parcelable placeholder for the real spans. This span is also passed back to an app's process when an accessibility service tries to click it. It contains enough information to track down the original clickable span so it can be called. 
@hide
/**
 * {@link ClickableSpan} cannot be parceled, but accessibility services need to be able to cause
 * their callback handlers to be called. This class serves as a parcelable placeholder for the
 * real spans.
 *
 * This span is also passed back to an app's process when an accessibility service tries to click
 * it. It contains enough information to track down the original clickable span so it can be
 * called.
 *
 * @hide
 */
public class AccessibilityClickableSpan extends ClickableSpan
        implements ParcelableSpan {
    // The id of the span this one replaces
    private final int mOriginalClickableSpanId;

    private int mWindowId = UNDEFINED_WINDOW_ID;
    private long mSourceNodeId = UNDEFINED_NODE_ID;
    private int mConnectionId = UNDEFINED_CONNECTION_ID;

    
Params:
originalClickableSpanId – The id of the span this one replaces/**
     * @param originalClickableSpanId The id of the span this one replaces
     */
    public AccessibilityClickableSpan(int originalClickableSpanId) {
        mOriginalClickableSpanId = originalClickableSpanId;
    }

    public AccessibilityClickableSpan(Parcel p) {
        mOriginalClickableSpanId = p.readInt();
    }

    @Override
    public int getSpanTypeId() {
        return getSpanTypeIdInternal();
    }

    @Override
    public int getSpanTypeIdInternal() {
        return TextUtils.ACCESSIBILITY_CLICKABLE_SPAN;
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        writeToParcelInternal(dest, flags);
    }

    @Override
    public void writeToParcelInternal(Parcel dest, int flags) {
        dest.writeInt(mOriginalClickableSpanId);
    }

    
Find the ClickableSpan that matches the one used to create this object.
Params:
text – The text that contains the original ClickableSpan.
Returns:
The ClickableSpan that matches this object, or null if no such object can be found./**
     * Find the ClickableSpan that matches the one used to create this object.
     *
     * @param text The text that contains the original ClickableSpan.
     * @return The ClickableSpan that matches this object, or {@code null} if no such object
     * can be found.
     */
    public ClickableSpan findClickableSpan(CharSequence text) {
        if (!(text instanceof Spanned)) {
            return null;
        }
        Spanned sp = (Spanned) text;
        ClickableSpan[] os = sp.getSpans(0, text.length(), ClickableSpan.class);
        for (int i = 0; i < os.length; i++) {
            if (os[i].getId() == mOriginalClickableSpanId) {
                return os[i];
            }
        }
        return null;
    }

    
Configure this object to perform clicks on the view that contains the original span.
Params:
accessibilityNodeInfo – The info corresponding to the view containing the original
                             span./**
     * Configure this object to perform clicks on the view that contains the original span.
     *
     * @param accessibilityNodeInfo The info corresponding to the view containing the original
     *                              span.
     */
    public void copyConnectionDataFrom(AccessibilityNodeInfo accessibilityNodeInfo) {
        mConnectionId = accessibilityNodeInfo.getConnectionId();
        mWindowId = accessibilityNodeInfo.getWindowId();
        mSourceNodeId = accessibilityNodeInfo.getSourceNodeId();
    }

    
Perform the click from an accessibility service. Will not work unless
setAccessibilityNodeInfo is called with a properly initialized node.
Params:
unused – This argument is required by the superclass but is unused. The real view will
be determined by the AccessibilityNodeInfo./**
     * Perform the click from an accessibility service. Will not work unless
     * setAccessibilityNodeInfo is called with a properly initialized node.
     *
     * @param unused This argument is required by the superclass but is unused. The real view will
     * be determined by the AccessibilityNodeInfo.
     */
    @Override
    public void onClick(View unused) {
        Bundle arguments = new Bundle();
        arguments.putParcelable(ACTION_ARGUMENT_ACCESSIBLE_CLICKABLE_SPAN, this);

        if ((mWindowId == UNDEFINED_WINDOW_ID) || (mSourceNodeId == UNDEFINED_NODE_ID)
                || (mConnectionId == UNDEFINED_CONNECTION_ID)) {
            throw new RuntimeException(
                    "ClickableSpan for accessibility service not properly initialized");
        }

        AccessibilityInteractionClient client = AccessibilityInteractionClient.getInstance();
        client.performAccessibilityAction(mConnectionId, mWindowId, mSourceNodeId,
                R.id.accessibilityActionClickOnClickableSpan, arguments);
    }

    public static final Parcelable.Creator<AccessibilityClickableSpan> CREATOR =
            new Parcelable.Creator<AccessibilityClickableSpan>() {
                @Override
                public AccessibilityClickableSpan createFromParcel(Parcel parcel) {
                    return new AccessibilityClickableSpan(parcel);
                }

                @Override
                public AccessibilityClickableSpan[] newArray(int size) {
                    return new AccessibilityClickableSpan[size];
                }
            };
}