/*
 * This file provided by Facebook is for non-commercial testing and evaluation
 * purposes only.  Facebook reserves all rights not expressly granted.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package org.goodev.material.widget.zoomable;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.RectF;
import android.graphics.drawable.Animatable;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.MotionEvent;

import com.facebook.common.internal.Preconditions;
import com.facebook.common.logging.FLog;
import com.facebook.drawee.controller.AbstractDraweeController;
import com.facebook.drawee.controller.BaseControllerListener;
import com.facebook.drawee.controller.ControllerListener;
import com.facebook.drawee.generic.GenericDraweeHierarchy;
import com.facebook.drawee.interfaces.DraweeController;
import com.facebook.drawee.view.DraweeView;

/**
 * DraweeView that has zoomable capabilities.
 * <p>
 * Once the image loads, pinch-to-zoom and translation gestures are enabled.
 */
public class ZoomableDraweeView extends DraweeView<GenericDraweeHierarchy>
        implements ZoomableController.Listener {

    private static final Class<?> TAG = ZoomableDraweeView.class;

    private static final float HUGE_IMAGE_SCALE_FACTOR_THRESHOLD = 1.1f;

    private final RectF mImageBounds = new RectF();
    private final RectF mViewBounds = new RectF();

    private final ControllerListener mControllerListener = new BaseControllerListener<Object>() {
        @Override
        public void onFinalImageSet(
                String id,
                @Nullable Object imageInfo,
                @Nullable Animatable animatable) {
            ZoomableDraweeView.this.onFinalImageSet();
        }

        @Override
        public void onRelease(String id) {
            ZoomableDraweeView.this.onRelease();
        }
    };

    private DraweeController mHugeImageController;
    private ZoomableController mZoomableController;

    public ZoomableDraweeView(Context context) {
        super(context);
        init();
    }

    public ZoomableDraweeView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public ZoomableDraweeView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }

    private void init() {
        mZoomableController = DoubleTapZoomableController.newInstance(getContext());
        mZoomableController.setListener(this);
    }

    public void setZoomableController(ZoomableController zoomableController) {
        Preconditions.checkNotNull(zoomableController);
        mZoomableController.setListener(null);
        mZoomableController = zoomableController;
        mZoomableController.setListener(this);
    }

    @Override
    public void setController(@Nullable DraweeController controller) {
        setControllers(controller, null);
    }

    private void setControllersInternal(
            @Nullable DraweeController controller,
            @Nullable DraweeController hugeImageController) {
        removeControllerListener(getController());
        addControllerListener(controller);
        mHugeImageController = hugeImageController;
        super.setController(controller);
    }

    /**
     * Sets the controllers for the normal and huge image.
     * <p>
     * <p> IMPORTANT: in order to avoid a flicker when switching to the huge image, the huge image
     * controller should have the normal-image-uri set as its low-res-uri.
     *
     * @param controller          controller to be initially used
     * @param hugeImageController controller to be used after the client starts zooming-in
     */
    public void setControllers(
            @Nullable DraweeController controller,
            @Nullable DraweeController hugeImageController) {
        setControllersInternal(null, null);
        mZoomableController.setEnabled(false);
        setControllersInternal(controller, hugeImageController);
    }

    private void maybeSetHugeImageController() {
        if (mHugeImageController != null &&
                mZoomableController.getScaleFactor() > HUGE_IMAGE_SCALE_FACTOR_THRESHOLD) {
            setControllersInternal(mHugeImageController, null);
        }
    }

    private void removeControllerListener(DraweeController controller) {
        if (controller instanceof AbstractDraweeController) {
            ((AbstractDraweeController) controller)
                    .removeControllerListener(mControllerListener);
        }
    }

    private void addControllerListener(DraweeController controller) {
        if (controller instanceof AbstractDraweeController) {
            ((AbstractDraweeController) controller)
                    .addControllerListener(mControllerListener);
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        int saveCount = canvas.save();
        canvas.concat(mZoomableController.getTransform());
        super.onDraw(canvas);
        canvas.restoreToCount(saveCount);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (mZoomableController.onTouchEvent(event)) {
            if (mZoomableController.getScaleFactor() > 1.0f) {
                getParent().requestDisallowInterceptTouchEvent(true);
            }
            //FLog.v(TAG, "onTouchEvent: view %x, handled by zoomable controller", this.hashCode());
            return true;
        }
        //FLog.v(TAG, "onTouchEvent: view %x, handled by the super", this.hashCode());
        return super.onTouchEvent(event);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        FLog.v(TAG, "onLayout: view %x", this.hashCode());
        super.onLayout(changed, left, top, right, bottom);
        updateZoomableControllerBounds();
    }

    private void onFinalImageSet() {
        FLog.v(TAG, "onFinalImageSet: view %x", this.hashCode());
        if (!mZoomableController.isEnabled()) {
            updateZoomableControllerBounds();
            mZoomableController.setEnabled(true);
        }
    }

    private void onRelease() {
        FLog.v(TAG, "onRelease: view %x", this.hashCode());
        mZoomableController.setEnabled(false);
    }

    @Override
    public void onTransformChanged(Matrix transform) {
        FLog.v(TAG, "onTransformChanged: view %x", this.hashCode());
        maybeSetHugeImageController();
        invalidate();
    }

    private void updateZoomableControllerBounds() {
        getHierarchy().getActualImageBounds(mImageBounds);
        mViewBounds.set(0, 0, getWidth(), getHeight());
        mZoomableController.setImageBounds(mImageBounds);
        mZoomableController.setViewBounds(mViewBounds);
        FLog.v(
                TAG,
                "updateZoomableControllerBounds: view %x, view bounds: %s, image bounds: %s",
                this.hashCode(),
                mViewBounds,
                mImageBounds);
    }
}