import { App } from "../../App";
import { Atom } from "../../Atom";
import { AtomBinder } from "../../core/AtomBinder";
import { AtomBridge } from "../../core/AtomBridge";
import { AtomComponent } from "../../core/AtomComponent";
import { AtomDispatcher } from "../../core/AtomDispatcher";
import { BindableProperty } from "../../core/BindableProperty";
import FormattedString from "../../core/FormattedString";
import { IClassOf, UMD } from "../../core/types";
import WebImage from "../../core/WebImage";
import { TypeKey } from "../../di/TypeKey";
import { NavigationService } from "../../services/NavigationService";
import { AtomStyle } from "../styles/AtomStyle";
import { AtomStyleSheet } from "../styles/AtomStyleSheet";
import { IStyleDeclaration } from "../styles/IStyleDeclaration";

declare global {
    // tslint:disable-next-line:interface-name
    export interface HTMLElement {
        atomControl: AtomControl;
        _logicalParent: HTMLElement;
        _templateParent: AtomControl;
    }
}

const defaultStyleSheets: { [key: string]: AtomStyle } = {};

/**
 * AtomControl class represents UI Component for a web browser.
 */

export class AtomControl extends AtomComponent<HTMLElement, AtomControl> {

    public defaultControlStyle: any;

    private mControlStyle: AtomStyle = undefined;
    public get controlStyle(): any {
        if (this.mControlStyle === undefined) {
            const key = TypeKey.get(this.defaultControlStyle || this.constructor);

            this.mControlStyle = defaultStyleSheets[key];
            if (this.mControlStyle) {
                return this.mControlStyle;
            }

            // let c = Object.getPrototypeOf(this);
            const t = this.theme;
            let c = this.constructor;
            while (c) {
                const style = t.getDefaultStyle(c);
                if (style) {
                    this.mControlStyle = style;
                    break;
                }
                if (this.defaultControlStyle) {
                    break;
                }
                c = Object.getPrototypeOf(c);
            }
            if (this.mControlStyle) {
                defaultStyleSheets[key] = this.mControlStyle;
                return this.mControlStyle;
            }
            if (this.defaultControlStyle) {
                this.mControlStyle = defaultStyleSheets[key] ||
                ( defaultStyleSheets[key] = this.theme.createNamedStyle(this.defaultControlStyle, key));
            }
            this.mControlStyle = this.mControlStyle || null;
        }
        return this.mControlStyle;
    }

    public set controlStyle(v: any) {
        if (v instanceof AtomStyle) {
            this.mControlStyle = v;
        } else {
            const key = TypeKey.get(v);
            this.mControlStyle = defaultStyleSheets[key] ||
            ( defaultStyleSheets[key] = this.theme.createNamedStyle(v, key));
        }
        AtomBinder.refreshValue(this, "controlStyle");
        this.invalidate();
    }

    private mTheme: AtomStyleSheet;
    private mCachedTheme: AtomStyleSheet;

    /**
     * Represents associated AtomStyleSheet with this visual hierarchy. AtomStyleSheet is
     * inherited by default.
     */
    public get theme(): AtomStyleSheet {
        return this.mTheme ||
            this.mCachedTheme ||
            (this.mCachedTheme = (this.parent ? this.parent.theme : this.app.resolve(AtomStyleSheet, false, null) ));
    }
    public set theme(v: AtomStyleSheet) {
        this.mTheme = v;
        AtomBridge.instance.refreshInherited(this, "theme");
    }

    /**
     * Gets Parent AtomControl of this control.
     */
    public get parent(): AtomControl {
        const ep = this.element._logicalParent || this.element.parentElement;
        if (!ep) {
            return null;
        }
        return this.atomParent(ep);
    }

    constructor(app: App, e?: HTMLElement) {
        super(app, e || document.createElement("div"));
    }

    public onPropertyChanged(name: string): void {
        super.onPropertyChanged(name);
        switch (name) {
            case "theme":
                this.mCachedTheme = null;
                AtomBinder.refreshValue(this, "style");
                break;
        }
    }

    public atomParent(e: HTMLElement): AtomControl {
        if (!e) {
            return;
        }
        const ep = e;
        if (ep.atomControl) {
            return ep.atomControl;
        }
        return this.atomParent(ep._logicalParent || ep.parentElement as HTMLElement);
    }

    public append(element: AtomControl | HTMLElement | Text): AtomControl {
        if (element instanceof AtomControl) {
            this.element.appendChild(element.element);
        } else {
            this.element.appendChild(element);
        }
        return this;
    }

    public updateSize(): void {
        this.onUpdateSize();
        AtomBridge.instance.visitDescendents(this.element, (e, ac) => {
            if (ac) {
                ac.updateSize();
                return false;
            }
            return true;
        });
    }

    protected preCreate(): void {
        // if (!this.element) {
        //     this.element = document.createElement("div");
        // }
    }

    protected setElementValue(element: HTMLElement, name: string, value: any): void {

        if (value === undefined) {
            return;
        }

        if (/^style/.test(name)) {

            if (name.length === 5) {
                element.setAttribute("style", value);
                return;
            }

            name = name.substr(5);
            name = name.charAt(0).toLowerCase() + name.substr(1);

            // this is style class...
            if (name === "class") {
                this.setElementClass(element, value);
                return;
            }
            if (value instanceof WebImage) {
                value = `url(${value})`;
            }
            element.style[name] = value;
            return;
        }

        if (/^event/.test(name)) {
            name = name.substr(5);
            name = name.charAt(0).toLowerCase() + name.substr(1);

            // element.style[name] = value;
            this.bindEvent(element, name, async (...e: any[]) => {
                try {
                    let pendingPromises = (element as any).pendingPromises;
                    if (pendingPromises) {
                        const last = pendingPromises[name];
                        if (last) {
                            if (UMD.debug) {
                                // tslint:disable-next-line:no-console
                                console.warn(`Previous promise exists for event ${name}`);
                            }
                            return;
                        }
                    }
                    const f = value as (...v: any[]) => any;
                    const pr = f.apply(this, e) as Promise<any>;
                    if (pr) {
                        if (!pendingPromises) {
                            (element as any).pendingPromises = pendingPromises = {};
                        }
                        pendingPromises[name] = pr;
                        try {
                            await pr;
                        } catch (error) {
                            if (/canceled|cancelled/i.test(error)) {
                                return;
                            }

                            const nav: NavigationService = this.app.resolve(NavigationService);
                            await nav.alert(error, "Error");
                        } finally {
                            delete pendingPromises[name];
                        }
                    }
                } catch (er1) {
                    // tslint:disable-next-line:no-console
                    console.error(er1);
                }
            });
            return;
        }

        switch (name) {
            case "text":
                element.textContent = value;
                break;
            case "formattedText":
                if (value instanceof FormattedString) {
                    (value as FormattedString).applyTo(this.app, element);
                } else {
                    element.textContent = (value || "").toString();
                }
                break;
            case "class":
                this.setElementClass(element, value, true);
                break;
            case "autofocus":
                this.app.callLater(() => {
                    const ie = element as HTMLInputElement;
                    if (ie) { ie.focus(); }
                });
            case "src":
                if (value && /^http\:/i.test(value)) {
                    (element as any).src = value.substr(5);
                } else {
                    (element as any).src = value;
                }
                break;
            default:
                element[name] = value;
        }
    }

    protected setElementClass(element: HTMLElement, value: any, clear?: boolean): void {
        const s = value as IStyleDeclaration;
        if (s && typeof s === "object") {
            if (!s.className) {
                if (clear) {
                    let sr = "";
                    for (const key in s) {
                        if (s.hasOwnProperty(key)) {
                            const sv = s[key];
                            if (sv) {
                                sr += (sr ? (" " + key) : key);
                            }
                        }
                    }
                    element.className = sr;
                    return;
                }
                for (const key in s) {
                    if (s.hasOwnProperty(key)) {
                        const sv = s[key];
                        if (sv) {
                            if (!element.classList.contains(key)) {
                                element.classList.add(key);
                            }
                        } else {
                            if (element.classList.contains(key)) {
                                element.classList.remove(key);
                            }
                        }
                    }
                }
                return;
            }
        }
        const sv1 = s ? (s.className || s.toString()) : "";
        element.className = sv1;
    }

    protected onUpdateSize(): void {
        // pending !!
    }

    protected removeAllChildren(e: HTMLElement): void {
        let child = e.firstElementChild as HTMLElement;
        while (child) {
            const c = child;
            child = child.nextElementSibling as HTMLElement;
            const ac = c;
            if (ac && ac.atomControl) {
                ac.atomControl.dispose();
            } else {
                // remove all children events
                this.unbindEvent(child);
                // remove all bindings
                this.unbind(child);
            }
            c.remove();
        }
    }

}