import { Component } from 'react';
import React from 'react';
import PropTypes from 'prop-types';
import { connect } from 'react-redux';

import { LayoutManager } from 'react-viewerbase';
import { OHIF } from 'ohif-core';

// Local Modules
import { unloadHandlers } from '../../../lib/unloadHandlers';
import { cornerstone, cornerstoneTools } from 'meteor/ohif:cornerstone';
import ConnectedCornerstoneViewport from '../ConnectedCornerstoneViewport.js';
import StackManager from '../../../lib/StackManager.js';

const { StudyLoadingListener, StudyPrefetcher, ResizeViewportManager } = OHIF.classes;

import './ViewerMain.styl';

window.ResizeViewportManager = window.ResizeViewportManager || new ResizeViewportManager();

function getCornerstoneStack(viewportData) {
    const {
        displaySetInstanceUid,
        studyInstanceUid,
    } = viewportData;

    // Create shortcut to displaySet
    const study = OHIF.viewer.Studies.findBy({
        studyInstanceUid,
    });

    const displaySet = study.displaySets.find((set) => {
        return set.displaySetInstanceUid === displaySetInstanceUid;
    });

    // Get stack from Stack Manager
    const stack = StackManager.findOrCreateStack(study, displaySet);
    stack.currentImageIdIndex = 0;

    return stack;
}

class ViewerMain extends Component {
    constructor(props) {
        super(props);

        this.state = {
            displaySets: []
        };

        this.getCornerstoneViewport = this.getCornerstoneViewport.bind(this);
    }

    componentDidMount() {
        // Attach the Window resize listener
        // Don't use jQuery here. "window.onresize" will always be null
        // If its necessary, check all the code for window.onresize getter
        // and change it to jQuery._data(window, 'events')['resize'].
        // Otherwise this function will be probably overrided.
        // See cineDialog instance.setResizeHandler function
        window.addEventListener('resize', window.ResizeViewportManager.getResizeHandler());

        // Add beforeUnload event handler to check for unsaved changes
        window.addEventListener('beforeunload', unloadHandlers.beforeUnload);

        const { studies } = this.props;
        this.studyPrefetcher = StudyPrefetcher.getInstance();
        this.studyPrefetcher.setStudies(studies);
        this.studyLoadingListener = StudyLoadingListener.getInstance();
        this.studyLoadingListener.clear();
        this.studyLoadingListener.addStudies(studies);

        // Get all the display sets for the viewer studies
        const displaySets = [];
        studies.forEach((study) => {
            study.displaySets.forEach(dSet => dSet.images.length && displaySets.push(dSet));
        });

        this.setState({
            displaySets
        });
    }

    getCornerstoneViewport(data, index) {
        const stack = getCornerstoneStack(data)
        const viewportData = {
            stack,
            ...data
        };

        return (<ConnectedCornerstoneViewport
            key={index}
            viewportData={viewportData}
            cornerstone={cornerstone}
            cornerstoneTools={cornerstoneTools}
        />);
    };

    render() {
        // TODO: re-add plugins back in
        const viewportData = this.state.displaySets.map((dSet, index) => {
            return this.getCornerstoneViewport(dSet, index);
        })

        // TODO: Connect LayoutManager to redux
        return (
            <div className="ViewerMain">
                <LayoutManager viewportData={viewportData}/>
            </div>
        );
    }

    componentWillUnmount() {
        // Remove the Window resize listener
        window.removeEventListener('resize', window.ResizeViewportManager.getResizeHandler());

        // Remove beforeUnload event handler...
        window.removeEventListener('beforeunload', unloadHandlers.beforeUnload);

        // Destroy the synchronizer used to update reference lines
        OHIF.viewer.updateImageSynchronizer.destroy();

        ProtocolEngine = null;

        // Stop prefetching when we close the viewer
        this.studyPrefetcher.destroy();

        // Destroy stack loading listeners when we close the viewer
        this.studyLoadingListener.clear();

        // Clear references to all stacks in the StackManager
        OHIF.viewerbase.stackManager.clearStacks();

        // @TypeSafeStudies
        // Clears OHIF.viewer.Studies collection
        OHIF.viewer.Studies.removeAll();

        // @TypeSafeStudies
        // Clears OHIF.viewer.StudyMetadataList collection
        OHIF.viewer.StudyMetadataList.removeAll();
    }
}

ViewerMain.propTypes = {
    studies: PropTypes.array.isRequired
};

export default ViewerMain;