/* spellchecker: disable */

import { auxiliaries, vec3 } from 'webgl-operate';

import {
    Camera,
    Canvas,
    Context,
    DefaultFramebuffer,
    EventProvider,
    FontFace,
    Invalidate,
    Label,
    LabelRenderPass,
    Navigation,
    Position3DLabel,
    Renderer,
    Text,
    Wizard,
} from 'webgl-operate';

import { Example } from './example';

/* spellchecker: enable */

// tslint:disable:max-classes-per-file


class Label3DRenderer extends Renderer {

    protected _extensions = false;

    protected _labelPass: LabelRenderPass;

    protected _labelWrap: Position3DLabel;
    protected _labelCentered: Position3DLabel;

    protected _camera: Camera;
    protected _navigation: Navigation;

    protected _defaultFBO: DefaultFramebuffer;

    protected _fontFace: FontFace | undefined;

    /**
     * Initializes and sets up rendering passes, navigation, loads a font face and links shaders with program.
     * @param context - valid context to create the object for.
     * @param identifier - meaningful name for identification of this instance.
     * @param eventProvider - required for mouse interaction
     * @returns - whether initialization was successful
     */
    protected onInitialize(context: Context, callback: Invalidate,
        eventProvider: EventProvider): boolean {

        /* Create framebuffers, textures, and render buffers. */

        this._defaultFBO = new DefaultFramebuffer(this._context, 'DefaultFBO');
        this._defaultFBO.initialize();

        /* Create and configure test navigation. */

        this._camera = new Camera();
        this._camera.eye = vec3.fromValues(0.0, 0.0, 1.0);
        this._camera.center = vec3.fromValues(0.0, 0.0, 0.0);
        this._camera.up = vec3.fromValues(0.0, 1.0, 0.0);
        this._camera.near = 0.1;
        this._camera.far = 4.0;

        this._navigation = new Navigation(callback, eventProvider);
        this._navigation.camera = this._camera;

        /* Create and configure label pass. */

        this._labelPass = new LabelRenderPass(context);
        this._labelPass.initialize();
        this._labelPass.camera = this._camera;
        this._labelPass.target = this._defaultFBO;
        this._labelPass.depthMask = false;

        FontFace.fromFile('./data/opensans2048p160d16.fnt', context)
            .then((fontFace) => {
                for (const label of this._labelPass.labels) {
                    label.fontFace = fontFace;
                }
                this._fontFace = fontFace;
                this.updateLabels();

                this.finishLoading();
                this.invalidate(true);
            })
            .catch((reason) => auxiliaries.log(auxiliaries.LogLevel.Error, reason));

        this.setupScene();

        return true;
    }

    /**
     * Uninitializes Buffers, Textures, and Program.
     */
    protected onUninitialize(): void {
        super.uninitialize();

        this._defaultFBO.uninitialize();
        this._labelPass.uninitialize();
    }

    protected onDiscarded(): void {
        this._altered.alter('canvasSize');
        this._altered.alter('clearColor');
        this._altered.alter('frameSize');
        this._altered.alter('multiFrameNumber');
    }

    /**
     * This is invoked in order to check if rendering of a frame is required by means of implementation specific
     * evaluation (e.g., lazy non continuous rendering). Regardless of the return value a new frame (preparation,
     * frame, swap) might be invoked anyway, e.g., when update is forced or canvas or context properties have
     * changed or the renderer was invalidated @see{@link invalidate}.
     * @returns whether to redraw
     */
    protected onUpdate(): boolean {
        this._navigation.update();

        for (const label of this._labelPass.labels) {
            if (label.altered || label.color.altered) {
                return true;
            }
        }
        return this._altered.any || this._camera.altered;
    }

    /**
     * This is invoked in order to prepare rendering of one or more frames, regarding multi-frame rendering and
     * camera-updates.
     */
    protected onPrepare(): void {

        if (this._altered.canvasSize) {
            this._camera.aspect = this._canvasSize[0] / this._canvasSize[1];
            this._camera.viewport = this._canvasSize;

            this.updateLabels();
        }

        if (this._altered.clearColor) {
            this._defaultFBO.clearColor(this._clearColor);
        }

        this._labelPass.update();

        this._altered.reset();
        this._camera.altered = false;
    }

    /**
     * After (1) update and (2) preparation are invoked, a frame is invoked. Renders both 2D and 3D labels.
     * @param frameNumber - for intermediate frames in accumulation rendering
     */
    protected onFrame(frameNumber: number): void {
        const gl = this._context.gl;

        gl.viewport(0, 0, this._camera.viewport[0], this._camera.viewport[1]);

        this._defaultFBO.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT, true, false);
        this._labelPass.frame();
    }

    /**
     * Sets up an example scene with 2D and 3D labels and sets the corresponding data on LabelGeometries. The
     * FontFace is set on each label by the LabelRenderPass.
     */
    protected setupScene(): void {

        /** Wrapped labels, showcasing Ellipsis and NewLine */

        const kafka = 'One morning, when Gregor Samsa woke from troubled dreams, he found himself transformed in \
his bed into a horrible vermin. He lay on his armour-like back, and if he lifted his head a little he could see his \
brown belly, slightly domed and divided by arches into stiff sections.';

        this._labelWrap = new Position3DLabel(new Text(`Wrap: ${kafka}`), Label.Type.Dynamic);
        this._labelWrap.wrap = true;
        this._labelWrap.lineWidth = 0.8;

        this._labelCentered = new Position3DLabel(new Text(`Label.LineAnchor\n+\nLabel.Alignment.Center`),
            Label.Type.Dynamic);
        this._labelCentered.lineAnchor = Label.LineAnchor.Center;
        this._labelCentered.alignment = Label.Alignment.Center;

        this._labelPass.labels = [this._labelWrap, this._labelCentered];

        for (const label of this._labelPass.labels) {
            label.fontSize = 0.05;
            label.color.fromHex('#fff');
            label.fontSizeUnit = Label.Unit.World;
        }
    }

    protected updateLabels(): void {
        if (!this._labelWrap.valid) {
            return;
        }

        this._labelWrap.position = [-0.3, 0.0, 0.0];
        this._labelWrap.up = [0.0, 0.0, -1.0];

        this._labelCentered.position = [0.0, 0.0, 0.0];
    }

}


export class Label3DExample extends Example {

    private _canvas: Canvas;
    private _renderer: Label3DRenderer;

    onInitialize(element: HTMLCanvasElement | string): boolean {

        this._canvas = new Canvas(element, { antialias: false });
        this._canvas.controller.multiFrameNumber = 1;
        this._canvas.framePrecision = Wizard.Precision.byte;
        this._canvas.frameScale = [1.0, 1.0];

        this._renderer = new Label3DRenderer();
        this._canvas.renderer = this._renderer;

        // Create a target cross as reference for coordinate origin [0,0,0]

        const hlStyle = 'z-index: 1; position: absolute; width: 100%; margin: 0; margin-left: 0%;'
            + 'border: none; border-bottom: 1pt solid #1c75bc; border-top: 1pt solid #1c75bc;';
        const vlStyle = 'z-index: 1; position: absolute; height: 100%; margin: 0; margin-top: 0%;'
            + 'border: none; border-left: 1pt solid #1cbc75; border-right: 1pt solid #1cbc75;';

        const hl = document.createElement('hl');
        hl.setAttribute('style', `${hlStyle} top: 50%;`);
        const vl = document.createElement('vl');
        vl.setAttribute('style', `${vlStyle} left: 50%;`);


        const parent = this._canvas.element!.parentElement!;
        const reference = this._canvas.element!;
        parent.insertBefore(hl, reference);
        parent.insertBefore(vl, reference);

        return true;
    }

    onUninitialize(): void {
        this._canvas.dispose();
        (this._renderer as Renderer).uninitialize();
    }

    get canvas(): Canvas {
        return this._canvas;
    }

    get renderer(): Label3DRenderer {
        return this._renderer;
    }

}