import Foundation
import UIKit
import AsyncDisplayKit
import Display
import TelegramPresentationData

private let animationDurationFactor: Double = 1.0

final class PeekControllerNode: ViewControllerTracingNode {
    private let requestDismiss: () -> Void
    
    private let presentationData: PresentationData
    private let theme: PeekControllerTheme
    
    private weak var controller: PeekController?
    
    private let blurView: UIView
    private let dimNode: ASDisplayNode
    private let containerBackgroundNode: ASImageNode
    private let containerNode: ASDisplayNode
    private let darkDimNode: ASDisplayNode
    
    private var validLayout: ContainerViewLayout?
    
    private var content: PeekControllerContent
    var contentNode: PeekControllerContentNode & ASDisplayNode
    private var contentNodeHasValidLayout = false
    
    private var topAccessoryNode: ASDisplayNode?
    private var fullScreenAccessoryNode: (PeekControllerAccessoryNode & ASDisplayNode)?

    private var actionsContainerNode: ContextActionsContainerNode
    
    private var hapticFeedback = HapticFeedback()

    private var initialContinueGesturePoint: CGPoint?
    private var didMoveFromInitialGesturePoint = false
    private var highlightedActionNode: ContextActionNodeProtocol?
    
    init(presentationData: PresentationData, controller: PeekController, content: PeekControllerContent, requestDismiss: @escaping () -> Void) {
        self.presentationData = presentationData
        self.requestDismiss = requestDismiss
        self.theme = PeekControllerTheme(presentationTheme: presentationData.theme)
        self.controller = controller
        
        self.dimNode = ASDisplayNode()
        
        let blurView = UIVisualEffectView(effect: UIBlurEffect(style: self.theme.isDark ? .dark : .light))
        blurView.isUserInteractionEnabled = false
        self.blurView = blurView
        
        self.darkDimNode = ASDisplayNode()
        self.darkDimNode.alpha = 0.0
        self.darkDimNode.backgroundColor = presentationData.theme.contextMenu.dimColor
        self.darkDimNode.isUserInteractionEnabled = false
        
        switch content.menuActivation() {
            case .drag:
                self.dimNode.backgroundColor = nil
                self.blurView.alpha = 1.0
            case .press:
                self.dimNode.backgroundColor = UIColor(white: self.theme.isDark ? 0.0 : 1.0, alpha: 0.5)
                self.blurView.alpha = 0.0
        }
        
        self.containerBackgroundNode = ASImageNode()
        self.containerBackgroundNode.isLayerBacked = true
        self.containerBackgroundNode.displaysAsynchronously = false
        
        self.containerNode = ASDisplayNode()
        
        self.content = content
        self.contentNode = content.node()
        self.topAccessoryNode = content.topAccessoryNode()
        self.fullScreenAccessoryNode = content.fullScreenAccessoryNode(blurView: blurView)
        self.fullScreenAccessoryNode?.alpha = 0.0
        
        var feedbackTapImpl: (() -> Void)?
        var activatedActionImpl: (() -> Void)?
        var requestLayoutImpl: (() -> Void)?
        self.actionsContainerNode = ContextActionsContainerNode(presentationData: presentationData, items: ContextController.Items(content: .list(content.menuItems())), getController: { [weak controller] in
            return controller
        }, actionSelected: { result in
            activatedActionImpl?()
        }, requestLayout: {
            requestLayoutImpl?()
        }, feedbackTap: {
            feedbackTapImpl?()
        }, blurBackground: true)
        self.actionsContainerNode.alpha = 0.0

        super.init()
        
        feedbackTapImpl = { [weak self] in
            self?.hapticFeedback.tap()
        }

        requestLayoutImpl = { [weak self] in
            self?.updateLayout()
        }
        
        if content.presentation() == .freeform {
            self.containerNode.isUserInteractionEnabled = false
        } else {
            self.containerNode.clipsToBounds = true
            self.containerNode.cornerRadius = 16.0
        }
        
        self.addSubnode(self.dimNode)
        self.view.addSubview(self.blurView)
        self.addSubnode(self.darkDimNode)
        self.containerNode.addSubnode(self.contentNode)
        
        self.addSubnode(self.containerNode)
        self.addSubnode(self.actionsContainerNode)
        
        if let fullScreenAccessoryNode = self.fullScreenAccessoryNode {
            self.fullScreenAccessoryNode?.dismiss = { [weak self] in
                self?.requestDismiss()
            }
            self.addSubnode(fullScreenAccessoryNode)
        }
        
        activatedActionImpl = { [weak self] in
            self?.requestDismiss()
        }
        
        self.hapticFeedback.prepareTap()
    }
    
    deinit {
    }
    
    override func didLoad() {
        super.didLoad()
        
        self.dimNode.view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(self.dimNodeTap(_:))))
        self.view.addGestureRecognizer(UIPanGestureRecognizer(target: self, action: #selector(self.panGesture(_:))))
    }

    func updateLayout() {
        if let layout = self.validLayout {
            self.containerLayoutUpdated(layout, transition: .immediate)
        }
    }
    
    func containerLayoutUpdated(_ layout: ContainerViewLayout, transition: ContainedViewLayoutTransition) {
        self.validLayout = layout
        
        transition.updateFrame(node: self.dimNode, frame: CGRect(origin: CGPoint(), size: layout.size))
        transition.updateFrame(node: self.darkDimNode, frame: CGRect(origin: CGPoint(), size: layout.size))
        transition.updateFrame(view: self.blurView, frame: CGRect(origin: CGPoint(), size: layout.size))
        
        var layoutInsets = layout.insets(options: [])
        let containerWidth = horizontalContainerFillingSizeForLayout(layout: layout, sideInset: layout.safeInsets.left)
       
        layoutInsets.left = floor((layout.size.width - containerWidth) / 2.0)
        layoutInsets.right = layoutInsets.left
        if !layoutInsets.bottom.isZero {
            layoutInsets.bottom -= 12.0
        }
        
        let maxContainerSize = CGSize(width: layout.size.width - 14.0 * 2.0, height: layout.size.height - layoutInsets.top - layoutInsets.bottom - 90.0)
        
        let contentSize = self.contentNode.updateLayout(size: maxContainerSize, transition: self.contentNodeHasValidLayout ? transition : .immediate)
        if self.contentNodeHasValidLayout {
            transition.updateFrame(node: self.contentNode, frame: CGRect(origin: CGPoint(), size: contentSize))
        } else {
            self.contentNode.frame = CGRect(origin: CGPoint(), size: contentSize)
        }
        
        let actionsSideInset: CGFloat = layout.safeInsets.left + 11.0
        let actionsSize = self.actionsContainerNode.updateLayout(widthClass: layout.metrics.widthClass, constrainedWidth: layout.size.width - actionsSideInset * 2.0, constrainedHeight: layout.size.height, transition: .immediate)
        
        let containerFrame: CGRect
        let actionsFrame: CGRect
        if layout.size.width > layout.size.height {
            if self.actionsContainerNode.alpha.isZero {
                containerFrame = CGRect(origin: CGPoint(x: floor((layout.size.width - contentSize.width) / 2.0), y: floor((layout.size.height - contentSize.height) / 2.0)), size: contentSize)
            } else {
                containerFrame = CGRect(origin: CGPoint(x: floor((layout.size.width - contentSize.width) / 3.0), y: floor((layout.size.height - contentSize.height) / 2.0)), size: contentSize)
            }
            actionsFrame = CGRect(origin: CGPoint(x: containerFrame.maxX + 32.0, y: floor((layout.size.height - actionsSize.height) / 2.0)), size: actionsSize)
        } else {
            switch self.content.presentation() {
                case .contained:
                    containerFrame = CGRect(origin: CGPoint(x: floor((layout.size.width - contentSize.width) / 2.0), y: floor((layout.size.height - contentSize.height) / 2.0)), size: contentSize)
                case .freeform:
                    containerFrame = CGRect(origin: CGPoint(x: floor((layout.size.width - contentSize.width) / 2.0), y: floor((layout.size.height - contentSize.height) / 3.0)), size: contentSize)
            }
            actionsFrame = CGRect(origin: CGPoint(x: floor((layout.size.width - actionsSize.width) / 2.0), y: containerFrame.maxY + 64.0), size: actionsSize)
        }
        transition.updateFrame(node: self.containerNode, frame: containerFrame)
                
        self.actionsContainerNode.updateSize(containerSize: actionsSize, contentSize: actionsSize)
        transition.updateFrame(node: self.actionsContainerNode, frame: actionsFrame)
        
        if let fullScreenAccessoryNode = self.fullScreenAccessoryNode {
            fullScreenAccessoryNode.updateLayout(size: layout.size, transition: transition)
            transition.updateFrame(node: fullScreenAccessoryNode, frame: CGRect(origin: .zero, size: layout.size))
        }
        
        self.contentNodeHasValidLayout = true
    }
    
    func animateIn(from rect: CGRect) {
        self.dimNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.3)
        self.blurView.layer.animateAlpha(from: 0.0, to: self.blurView.alpha, duration: 0.3)
        
        let offset = CGPoint(x: rect.midX - self.containerNode.position.x, y: rect.midY - self.containerNode.position.y)
        self.containerNode.layer.animateSpring(from: NSValue(cgPoint: offset), to: NSValue(cgPoint: CGPoint()), keyPath: "position", duration: 0.4, initialVelocity: 0.0, damping: 110.0, additive: true)
        self.containerNode.layer.animateSpring(from: 0.1 as NSNumber, to: 1.0 as NSNumber, keyPath: "transform.scale", duration: 0.4, initialVelocity: 0.0, damping: 110.0)
        self.containerNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.15)
        
        if let topAccessoryNode = self.topAccessoryNode {
            topAccessoryNode.layer.animateSpring(from: NSValue(cgPoint: offset), to: NSValue(cgPoint: CGPoint()), keyPath: "position", duration: 0.4, initialVelocity: 0.0, damping: 110.0, additive: true)
            topAccessoryNode.layer.animateSpring(from: 0.1 as NSNumber, to: 1.0 as NSNumber, keyPath: "transform.scale", duration: 0.4, initialVelocity: 0.0, damping: 110.0)
            topAccessoryNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.15)
        }
                
        if case .press = self.content.menuActivation() {
            self.hapticFeedback.tap()
        } else {
            self.hapticFeedback.impact()
        }
    }
    
    func animateOut(to rect: CGRect, completion: @escaping () -> Void) {
        self.dimNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.2, removeOnCompletion: false)
        self.blurView.layer.animateAlpha(from: self.blurView.alpha, to: 0.0, duration: 0.25, removeOnCompletion: false)
        self.darkDimNode.layer.animateAlpha(from: self.darkDimNode.alpha, to: 0.0, duration: 0.2, removeOnCompletion: false)
        
        let springDuration: Double = 0.42 * animationDurationFactor
        let springDamping: CGFloat = 104.0
        
        let offset = CGPoint(x: rect.midX - self.containerNode.position.x, y: rect.midY - self.containerNode.position.y)
        self.containerNode.layer.animateSpring(from: NSValue(cgPoint: CGPoint()), to: NSValue(cgPoint: offset), keyPath: "position", duration: springDuration, initialVelocity: 0.0, damping: springDamping, additive: true, completion: { _ in
            completion()
        })
        self.containerNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.2, removeOnCompletion: false)
        self.containerNode.layer.animateScale(from: 1.0, to: 0.1, duration: 0.25, removeOnCompletion: false)
           
        if !self.actionsContainerNode.alpha.isZero {
            let actionsOffset = CGPoint(x: rect.midX - self.actionsContainerNode.position.x, y: rect.midY - self.actionsContainerNode.position.y)
            self.actionsContainerNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.2 * animationDurationFactor, removeOnCompletion: false)
            self.actionsContainerNode.layer.animateSpring(from: 1.0 as NSNumber, to: 0.0 as NSNumber, keyPath: "transform.scale", duration: springDuration, initialVelocity: 0.0, damping: springDamping, removeOnCompletion: false)
            self.actionsContainerNode.layer.animateSpring(from: NSValue(cgPoint: CGPoint()), to: NSValue(cgPoint: actionsOffset), keyPath: "position", duration: springDuration, initialVelocity: 0.0, damping: springDamping, additive: true)
        }
        
        if let fullScreenAccessoryNode = self.fullScreenAccessoryNode, !fullScreenAccessoryNode.alpha.isZero {
            fullScreenAccessoryNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.2 * animationDurationFactor, removeOnCompletion: false)
        }
    }
    
    @objc func dimNodeTap(_ recognizer: UITapGestureRecognizer) {
        if case .ended = recognizer.state {
            self.requestDismiss()
        }
    }
    
    @objc func panGesture(_ recognizer: UIPanGestureRecognizer) {
        guard case .drag = self.content.menuActivation() else {
            return
        }
        
        let location = recognizer.location(in: self.view)
        switch recognizer.state {
            case .began:
                break
            case .changed:
                self.applyDraggingOffset(location)
            case .cancelled, .ended:
                self.endDragging(location)
            default:
                break
        }
    }
    
    func applyDraggingOffset(_ offset: CGPoint) {
        let localPoint = offset
        let initialPoint: CGPoint
        if let current = self.initialContinueGesturePoint {
            initialPoint = current
        } else {
            initialPoint = localPoint
            self.initialContinueGesturePoint = localPoint
        }
        if !self.actionsContainerNode.alpha.isZero {
            if !self.didMoveFromInitialGesturePoint {
                let distance = abs(localPoint.y - initialPoint.y)
                if distance > 12.0 {
                    self.didMoveFromInitialGesturePoint = true
                }
            }
            if self.didMoveFromInitialGesturePoint {
                let actionPoint = self.view.convert(localPoint, to: self.actionsContainerNode.view)
                let actionNode = self.actionsContainerNode.actionNode(at: actionPoint)
                if self.highlightedActionNode !== actionNode {
                    self.highlightedActionNode?.setIsHighlighted(false)
                    self.highlightedActionNode = actionNode
                    if let actionNode = actionNode {
                        actionNode.setIsHighlighted(true)
                        self.hapticFeedback.tap()
                    }
                }
            }
        }
    }
    
    func activateMenu() {
        if self.content.menuItems().isEmpty {
            if let fullScreenAccessoryNode = self.fullScreenAccessoryNode {
                fullScreenAccessoryNode.alpha = 1.0
                fullScreenAccessoryNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.15)
                
                let previousBlurAlpha = self.blurView.alpha
                self.blurView.alpha = 1.0
                self.blurView.layer.animateAlpha(from: previousBlurAlpha, to: self.blurView.alpha, duration: 0.3)
            }
            return
        }
        if case .press = self.content.menuActivation() {
            self.hapticFeedback.impact()
        }
        
        let springDuration: Double = 0.42 * animationDurationFactor
        let springDamping: CGFloat = 104.0
        
        let previousBlurAlpha = self.blurView.alpha
        self.blurView.alpha = 1.0
        self.blurView.layer.animateAlpha(from: previousBlurAlpha, to: self.blurView.alpha, duration: 0.3)
        
        let previousDarkDimAlpha = self.darkDimNode.alpha
        self.darkDimNode.alpha = 1.0
        self.darkDimNode.layer.animateAlpha(from: previousDarkDimAlpha, to: 1.0, duration: 0.3)
        
        self.actionsContainerNode.alpha = 1.0
        self.actionsContainerNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.2 * animationDurationFactor)
        self.actionsContainerNode.layer.animateSpring(from: 0.1 as NSNumber, to: 1.0 as NSNumber, keyPath: "transform.scale", duration: springDuration, initialVelocity: 0.0, damping: springDamping)
        
        let localContentSourceFrame = self.containerNode.frame
        self.actionsContainerNode.layer.animateSpring(from: NSValue(cgPoint: CGPoint(x: localContentSourceFrame.center.x - self.actionsContainerNode.position.x, y: localContentSourceFrame.center.y - self.actionsContainerNode.position.y)), to: NSValue(cgPoint: CGPoint()), keyPath: "position", duration: springDuration, initialVelocity: 0.0, damping: springDamping, additive: true)
        
        if let layout = self.validLayout {
            self.containerLayoutUpdated(layout, transition: .animated(duration: springDuration, curve: .spring))
        }
    }
    
    func endDragging(_ location: CGPoint) {
        if self.didMoveFromInitialGesturePoint {
            if let highlightedActionNode = self.highlightedActionNode {
                self.highlightedActionNode = nil
                highlightedActionNode.performAction()
            }
        } else if self.actionsContainerNode.alpha.isZero {
            if let fullScreenAccessoryNode = self.fullScreenAccessoryNode, !fullScreenAccessoryNode.alpha.isZero {
            } else {
                self.requestDismiss()
            }
        }
    }
    
    func updateContent(content: PeekControllerContent) {
        let contentNode = self.contentNode
        contentNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.15, removeOnCompletion: false, completion: { [weak contentNode] _ in
            contentNode?.removeFromSupernode()
        })
        contentNode.layer.animateScale(from: 1.0, to: 0.2, duration: 0.15, removeOnCompletion: false)
        
        self.content = content
        self.contentNode = content.node()
        self.containerNode.addSubnode(self.contentNode)
        self.contentNodeHasValidLayout = false
        
        let previousActionsContainerNode = self.actionsContainerNode
        self.actionsContainerNode = ContextActionsContainerNode(presentationData: self.presentationData, items: ContextController.Items(content: .list(content.menuItems())), getController: { [weak self] in
            return self?.controller
        }, actionSelected: { [weak self] result in
            self?.requestDismiss()
        }, requestLayout: { [weak self] in
            self?.updateLayout()
        }, feedbackTap: { [weak self] in
            self?.hapticFeedback.tap()
        }, blurBackground: true)
        self.actionsContainerNode.alpha = 0.0
        self.insertSubnode(self.actionsContainerNode, aboveSubnode: previousActionsContainerNode)
        previousActionsContainerNode.removeFromSupernode()
        
        self.contentNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.1)
        self.contentNode.layer.animateSpring(from: 0.35 as NSNumber, to: 1.0 as NSNumber, keyPath: "transform.scale", duration: 0.5)
        
        if let layout = self.validLayout {
            self.containerLayoutUpdated(layout, transition: .animated(duration: 0.15, curve: .easeInOut))
        }
        
        self.hapticFeedback.tap()
    }
}