/*===============================================================================
Copyright (c) 2016,2018 PTC Inc. All Rights Reserved.

Copyright (c) 2012-2014 Qualcomm Connected Experiences, Inc. All Rights Reserved.

Vuforia is a trademark of PTC Inc., registered in the United States and other 
countries.
===============================================================================*/

package com.hoperun.cordova.vuforia;

import android.app.Activity;
import android.util.Log;

import com.vuforia.ImageTargetBuilder;
import com.vuforia.ObjectTracker;
import com.vuforia.Renderer;
import com.vuforia.TrackableSource;
import com.vuforia.TrackerManager;
import com.vuforia.Vec2F;
import com.vuforia.VideoBackgroundConfig;


public class RefFreeFrame {
    
    private static final String LOGTAG = "RefFreeFrame";
    
    // Some helper functions
    enum STATUS {
        STATUS_IDLE, STATUS_SCANNING, STATUS_CREATING, STATUS_SUCCESS
    }
    
    private STATUS curStatus;
    
    // / Current color of the target finder. This changes color
    // / depending on frame quality.
    private final float[] colorFrame;
    
    // / Half of the screen size, used often in the rendering pipeline
    private final Vec2F halfScreenSize;
    
    // / Keep track of the time between frames for color transitions
    private long lastFrameTime;
    
    // All rendering methods are contained in this class for easy
    // extraction/abstraction
    private final RefFreeFrameGL frameGL;
    
    // The latest trackable source to be extracted from the Target Builder
    private TrackableSource trackableSource;

    private final CordovaVuforia mCordovaVuforia;

    // Function used to transition in the range [0, 1]
    private float transition(float v0, float inc) {

        float minValue = 0.0f;
        float maxValue = 1.0f;

        float vOut = v0 + inc;

        return (vOut < minValue ? minValue : (vOut > maxValue ? maxValue : vOut));

    }
    
    public RefFreeFrame(Activity activity, CordovaVuforia cordovaVuforia) {

        mCordovaVuforia = cordovaVuforia;
        colorFrame = new float[4];
        curStatus = STATUS.STATUS_IDLE;
        trackableSource = null;
        colorFrame[0] = 1.0f;
        colorFrame[1] = 0.0f;
        colorFrame[2] = 0.0f;
        colorFrame[3] = 0.75f;
        
        frameGL = new RefFreeFrameGL(activity);
        halfScreenSize = new Vec2F();

    }

    public void init() {

        // load the frame texture
        frameGL.getTextures();
        
        trackableSource = null;

    }

    public void deInit() {

        TrackerManager trackerManager = TrackerManager.getInstance();
        ObjectTracker objectTracker = (ObjectTracker) (trackerManager.getTracker(ObjectTracker.getClassType()));
        if (objectTracker != null) {
            ImageTargetBuilder targetBuilder = objectTracker.getImageTargetBuilder();
            if (targetBuilder != null && (targetBuilder.getFrameQuality() != ImageTargetBuilder.FRAME_QUALITY.FRAME_QUALITY_NONE)) {
                targetBuilder.stopScan();
            }
        }

    }

    public void initGL(int screenWidth, int screenHeight) {

        if (!frameGL.init(screenWidth, screenHeight)) {
            Log.e(LOGTAG, "Failed to init RefFreeFrameGL");
            return;
        }
        
        Renderer renderer = Renderer.getInstance();
        VideoBackgroundConfig vc = renderer.getVideoBackgroundConfig();
        int temp[] = vc.getSize().getData();
        float[] videoBackgroundConfigSize = new float[2];
        videoBackgroundConfigSize[0] = temp[0] * 0.5f;
        videoBackgroundConfigSize[1] = temp[1] * 0.5f;
        
        halfScreenSize.setData(videoBackgroundConfigSize);
        
        // sets last frame timer
        lastFrameTime = System.currentTimeMillis();
        
        reset();

    }

    public void reset() {

        curStatus = STATUS.STATUS_IDLE;
        
    }

    public void setCreating() {

        curStatus = STATUS.STATUS_CREATING;

    }

    private void updateUIState(ImageTargetBuilder targetBuilder, int frameQuality) {

        // ** Elapsed time
        long elapsedTimeMS = System.currentTimeMillis() - lastFrameTime;
        lastFrameTime += elapsedTimeMS;
        
        // This is a time-dependent value used for transitions in 
        // the range [0,1] over the period of half of a second.
        float transitionHalfSecond = elapsedTimeMS * 0.002f;
        
        STATUS newStatus = curStatus;
        
        switch (curStatus) {
            case STATUS_IDLE:
                if (frameQuality != ImageTargetBuilder.FRAME_QUALITY.FRAME_QUALITY_NONE)
                    newStatus = STATUS.STATUS_SCANNING;
                
                break;
            case STATUS_SCANNING:
                switch (frameQuality) {
                // bad target quality, render the frame white until a match is
                // made, then go to green
                    case ImageTargetBuilder.FRAME_QUALITY.FRAME_QUALITY_LOW:
                        colorFrame[0] = 1.0f;
                        colorFrame[1] = 1.0f;
                        colorFrame[2] = 1.0f;

                        break;
                    // good target, switch to green over half a second
                    case ImageTargetBuilder.FRAME_QUALITY.FRAME_QUALITY_HIGH:
                    case ImageTargetBuilder.FRAME_QUALITY.FRAME_QUALITY_MEDIUM:
                        colorFrame[0] = transition(colorFrame[0],
                            -transitionHalfSecond);
                        colorFrame[1] = transition(colorFrame[1],
                            transitionHalfSecond);
                        colorFrame[2] = transition(colorFrame[2],
                            -transitionHalfSecond);
                        
                        break;
                }

                break;
            case STATUS_CREATING:
                // check for new result
                // if found, set to success, success time and:
                TrackableSource newTrackableSource = targetBuilder.getTrackableSource();
                if (newTrackableSource != null) {
                    newStatus = STATUS.STATUS_SUCCESS;
                    trackableSource = newTrackableSource;
                    
                    mCordovaVuforia.targetCreated();
                }
            default:
                break;
        }
        
        curStatus = newStatus;

    }

    public void render() {

        // Get the image tracker
        TrackerManager trackerManager = TrackerManager.getInstance();
        ObjectTracker objectTracker = (ObjectTracker) (trackerManager.getTracker(ObjectTracker.getClassType()));
        
        // Get the frame quality from the target builder
        ImageTargetBuilder targetBuilder = objectTracker.getImageTargetBuilder();
        int frameQuality = targetBuilder.getFrameQuality();
        
        // Update the UI internal state variables
        updateUIState(targetBuilder, frameQuality);

        if (curStatus == STATUS.STATUS_SUCCESS) {
            curStatus = STATUS.STATUS_IDLE;
            
            Log.d(LOGTAG, "Built target, reactivating dataset with new target");
            mCordovaVuforia.doStartTrackers();
        }

        // Renders the hints
        switch (curStatus) {
            case STATUS_SCANNING:
                renderScanningViewfinder();
                break;
            default:
                break;
        
        }

    }

    private void renderScanningViewfinder() {

        frameGL.setModelViewScale();
        frameGL.setColor(colorFrame);
        frameGL.renderViewfinder();

    }

    public boolean hasNewTrackableSource() {

        return (trackableSource != null);

    }

    public TrackableSource getNewTrackableSource() {

        TrackableSource result = trackableSource;
        trackableSource = null;

        return result;

    }

}