import { ControlStateChangeListener } from "../core/control-state-change";
import {
    ButtonBase, PseudoClassHandler, Length, layout,
    borderTopWidthProperty, borderRightWidthProperty, borderBottomWidthProperty, borderLeftWidthProperty,
    paddingTopProperty, paddingRightProperty, paddingBottomProperty, paddingLeftProperty,
    whiteSpaceProperty, WhiteSpace, textAlignmentProperty, TextAlignment, View
} from "./button-common";

export * from "./button-common";

export class Button extends ButtonBase {
    public nativeViewProtected: UIButton;

    private _tapHandler: NSObject;
    private _stateChangedHandler: ControlStateChangeListener;

    constructor() {
        super();
        this.nativeViewProtected = UIButton.buttonWithType(UIButtonType.System);

        this._tapHandler = TapHandlerImpl.initWithOwner(new WeakRef(this));
        this.nativeViewProtected.addTargetActionForControlEvents(this._tapHandler, "tap", UIControlEvents.TouchUpInside);
    }

    get ios() {
        return this.nativeViewProtected;
    }

    public onUnloaded() {
        super.onUnloaded();
        if (this._stateChangedHandler) {
            this._stateChangedHandler.stop();
        }
    }

    @PseudoClassHandler("normal", "highlighted", "pressed", "active")
    _updateHandler(subscribe: boolean) {
        if (subscribe) {
            if (!this._stateChangedHandler) {
                this._stateChangedHandler = new ControlStateChangeListener(this.nativeViewProtected, (s: string) => {
                    this._goToVisualState(s);
                });
            }
            this._stateChangedHandler.start();
        } else {
            this._stateChangedHandler.stop();
        }
    }

    [borderTopWidthProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.top,
            unit: "px"
        };
    }
    [borderTopWidthProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let top = layout.toDeviceIndependentPixels(this.effectivePaddingTop + this.effectiveBorderTopWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: top, left: inset.left, bottom: inset.bottom, right: inset.right };
    }

    [borderRightWidthProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.right,
            unit: "px"
        };
    }
    [borderRightWidthProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let right = layout.toDeviceIndependentPixels(this.effectivePaddingRight + this.effectiveBorderRightWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: inset.top, left: inset.left, bottom: inset.bottom, right: right };
    }

    [borderBottomWidthProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.bottom,
            unit: "px"
        };
    }
    [borderBottomWidthProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let bottom = layout.toDeviceIndependentPixels(this.effectivePaddingBottom + this.effectiveBorderBottomWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: inset.top, left: inset.left, bottom: bottom, right: inset.right };
    }

    [borderLeftWidthProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.left,
            unit: "px"
        };
    }
    [borderLeftWidthProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let left = layout.toDeviceIndependentPixels(this.effectivePaddingLeft + this.effectiveBorderLeftWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: inset.top, left: left, bottom: inset.bottom, right: inset.right };
    }

    [paddingTopProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.top,
            unit: "px"
        };
    }
    [paddingTopProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let top = layout.toDeviceIndependentPixels(this.effectivePaddingTop + this.effectiveBorderTopWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: top, left: inset.left, bottom: inset.bottom, right: inset.right };
    }

    [paddingRightProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.right,
            unit: "px"
        };
    }
    [paddingRightProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let right = layout.toDeviceIndependentPixels(this.effectivePaddingRight + this.effectiveBorderRightWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: inset.top, left: inset.left, bottom: inset.bottom, right: right };
    }

    [paddingBottomProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.bottom,
            unit: "px"
        };
    }
    [paddingBottomProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let bottom = layout.toDeviceIndependentPixels(this.effectivePaddingBottom + this.effectiveBorderBottomWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: inset.top, left: inset.left, bottom: bottom, right: inset.right };
    }

    [paddingLeftProperty.getDefault](): Length {
        return {
            value: this.nativeViewProtected.contentEdgeInsets.left,
            unit: "px"
        };
    }
    [paddingLeftProperty.setNative](value: Length) {
        let inset = this.nativeViewProtected.contentEdgeInsets;
        let left = layout.toDeviceIndependentPixels(this.effectivePaddingLeft + this.effectiveBorderLeftWidth);
        this.nativeViewProtected.contentEdgeInsets = { top: inset.top, left: left, bottom: inset.bottom, right: inset.right };
    }

    [textAlignmentProperty.setNative](value: TextAlignment) {
        switch (value) {
            case "left":
                this.nativeViewProtected.titleLabel.textAlignment = NSTextAlignment.Left;
                this.nativeViewProtected.contentHorizontalAlignment = UIControlContentHorizontalAlignment.Left;
                break;
            case "initial":
            case "center":
                this.nativeViewProtected.titleLabel.textAlignment = NSTextAlignment.Center;
                this.nativeViewProtected.contentHorizontalAlignment = UIControlContentHorizontalAlignment.Center;
                break;
            case "right":
                this.nativeViewProtected.titleLabel.textAlignment = NSTextAlignment.Right;
                this.nativeViewProtected.contentHorizontalAlignment = UIControlContentHorizontalAlignment.Right;
                break;
        }
    }

    [whiteSpaceProperty.setNative](value: WhiteSpace) {
        const nativeView = this.nativeViewProtected.titleLabel;
        switch (value) {
            case "normal":
                nativeView.lineBreakMode = NSLineBreakMode.ByWordWrapping;
                nativeView.numberOfLines = 0;
                break;
            case "nowrap":
            case "initial":
                nativeView.lineBreakMode = NSLineBreakMode.ByTruncatingMiddle;
                nativeView.numberOfLines = 1;
                break;
        }
    }

    public onMeasure(widthMeasureSpec: number, heightMeasureSpec: number): void {
        // If there is text-wrap UIButton.sizeThatFits will return wrong result (not respecting the text wrap).
        // So fallback to original onMeasure if there is no text-wrap and use custom measure otherwise.
        if (!this.textWrap) {
            return super.onMeasure(widthMeasureSpec, heightMeasureSpec)
        }

        let nativeView = this.nativeViewProtected;
        if (nativeView) {
            const width = layout.getMeasureSpecSize(widthMeasureSpec);
            const widthMode = layout.getMeasureSpecMode(widthMeasureSpec);
            const height = layout.getMeasureSpecSize(heightMeasureSpec);
            const heightMode = layout.getMeasureSpecMode(heightMeasureSpec);

            const horizontalPadding = this.effectivePaddingLeft + this.effectiveBorderLeftWidth + this.effectivePaddingRight + this.effectiveBorderRightWidth;
            let verticalPadding = this.effectivePaddingTop + this.effectiveBorderTopWidth + this.effectivePaddingBottom + this.effectiveBorderBottomWidth;

            // The default button padding for UIButton - 6dip top and bottom.
            if (verticalPadding === 0) {
                verticalPadding = layout.toDevicePixels(12);
            }

            const desiredSize = layout.measureNativeView(
                nativeView.titleLabel,
                width - horizontalPadding, widthMode,
                height - verticalPadding, heightMode);

            desiredSize.width = desiredSize.width + horizontalPadding;
            desiredSize.height = desiredSize.height + verticalPadding;

            const measureWidth = Math.max(desiredSize.width, this.effectiveMinWidth);
            const measureHeight = Math.max(desiredSize.height, this.effectiveMinHeight);

            const widthAndState = View.resolveSizeAndState(measureWidth, width, widthMode, 0);
            const heightAndState = View.resolveSizeAndState(measureHeight, height, heightMode, 0);

            this.setMeasuredDimension(widthAndState, heightAndState);
        }
    }
}

class TapHandlerImpl extends NSObject {
    private _owner: WeakRef<Button>;

    public static initWithOwner(owner: WeakRef<Button>): TapHandlerImpl {
        let handler = <TapHandlerImpl>TapHandlerImpl.new();
        handler._owner = owner;
        return handler;
    }

    public tap(args) {
        let owner = this._owner.get();
        if (owner) {
            owner._emit(ButtonBase.tapEvent);
        }
    }

    public static ObjCExposedMethods = {
        "tap": { returns: interop.types.void, params: [interop.types.id] }
    };
}
