import Foundation
import UIKit
import Display
import AsyncDisplayKit
import Postbox
import TelegramCore
import SwiftSignalKit
import TelegramPresentationData
import TelegramUIPreferences
import TelegramAudio
import AccountContext
import LocalizedPeerData
import PhotoResources
import CallsEmoji
import TooltipUI
import AlertUI
import PresentationDataUtils
import DeviceAccess
import ContextUI
import AppBundle

private func interpolateFrame(from fromValue: CGRect, to toValue: CGRect, t: CGFloat) -> CGRect {
    return CGRect(x: floorToScreenPixels(toValue.origin.x * t + fromValue.origin.x * (1.0 - t)), y: floorToScreenPixels(toValue.origin.y * t + fromValue.origin.y * (1.0 - t)), width: floorToScreenPixels(toValue.size.width * t + fromValue.size.width * (1.0 - t)), height: floorToScreenPixels(toValue.size.height * t + fromValue.size.height * (1.0 - t)))
}

private func interpolate(from: CGFloat, to: CGFloat, value: CGFloat) -> CGFloat {
    return (1.0 - value) * from + value * to
}

final class CallVideoNode: ASDisplayNode, PreviewVideoNode {
    private var placeholderImageNode: ASImageNode?
    
    private let videoTransformContainer: ASDisplayNode
    private let videoView: PresentationCallVideoView
    
    private var effectView: UIVisualEffectView?
    private let videoPausedNode: ImmediateTextNode
    
    private var isBlurred: Bool = false
    private var currentCornerRadius: CGFloat = 0.0
    
    private let isReadyUpdated: () -> Void
    private(set) var isReady: Bool = false
    private var isReadyTimer: SwiftSignalKit.Timer?
    
    private let readyPromise = ValuePromise(false)
    var ready: Signal<Bool, NoError> {
        return self.readyPromise.get()
    }
    
    private let isFlippedUpdated: (CallVideoNode) -> Void
    
    private(set) var currentOrientation: PresentationCallVideoView.Orientation
    private(set) var currentAspect: CGFloat = 0.0
    
    private var previousVideoHeight: CGFloat?
    
    init(videoView: PresentationCallVideoView, displayPlaceholderUntilReady: Bool = false, disabledText: String?, assumeReadyAfterTimeout: Bool, isReadyUpdated: @escaping () -> Void, orientationUpdated: @escaping () -> Void, isFlippedUpdated: @escaping (CallVideoNode) -> Void) {
        self.isReadyUpdated = isReadyUpdated
        self.isFlippedUpdated = isFlippedUpdated
        
        self.videoTransformContainer = ASDisplayNode()
        self.videoView = videoView
        videoView.view.clipsToBounds = true
        videoView.view.backgroundColor = .black
        
        self.currentOrientation = videoView.getOrientation()
        self.currentAspect = videoView.getAspect()
        
        self.videoPausedNode = ImmediateTextNode()
        self.videoPausedNode.alpha = 0.0
        self.videoPausedNode.maximumNumberOfLines = 3
        
        super.init()
        
        self.backgroundColor = .black
        self.clipsToBounds = true
        
        if #available(iOS 13.0, *) {
            self.layer.cornerCurve = .continuous
        }
        
        self.videoTransformContainer.view.addSubview(self.videoView.view)
        self.addSubnode(self.videoTransformContainer)
        
        if displayPlaceholderUntilReady {
            let placeholderImageNode = ASImageNode()
            placeholderImageNode.image = UIImage(bundleImageName: "Camera/SelfiePlaceholder")
            self.placeholderImageNode = placeholderImageNode
            self.addSubnode(placeholderImageNode)
        }
        
        if let disabledText = disabledText {
            self.videoPausedNode.attributedText = NSAttributedString(string: disabledText, font: Font.regular(17.0), textColor: .white)
            self.addSubnode(self.videoPausedNode)
        }
        
        self.videoView.setOnFirstFrameReceived { [weak self] aspectRatio in
            Queue.mainQueue().async {
                guard let strongSelf = self else {
                    return
                }
                if !strongSelf.isReady {
                    strongSelf.isReady = true
                    strongSelf.readyPromise.set(true)
                    strongSelf.isReadyTimer?.invalidate()
                    strongSelf.isReadyUpdated()
                    
                    if let placeholderImageNode = strongSelf.placeholderImageNode {
                        strongSelf.placeholderImageNode = nil
                        placeholderImageNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.3, removeOnCompletion: false, completion: { [weak placeholderImageNode] _ in
                            placeholderImageNode?.removeFromSupernode()
                        })
                    }
                }
            }
        }
        
        self.videoView.setOnOrientationUpdated { [weak self] orientation, aspect in
            Queue.mainQueue().async {
                guard let strongSelf = self else {
                    return
                }
                if strongSelf.currentOrientation != orientation || strongSelf.currentAspect != aspect {
                    strongSelf.currentOrientation = orientation
                    strongSelf.currentAspect = aspect
                    orientationUpdated()
                }
            }
        }
        
        self.videoView.setOnIsMirroredUpdated { [weak self] _ in
            Queue.mainQueue().async {
                guard let strongSelf = self else {
                    return
                }
                strongSelf.isFlippedUpdated(strongSelf)
            }
        }
        
        if assumeReadyAfterTimeout {
            self.isReadyTimer = SwiftSignalKit.Timer(timeout: 3.0, repeat: false, completion: { [weak self] in
                guard let strongSelf = self else {
                    return
                }
                if !strongSelf.isReady {
                    strongSelf.isReady = true
                    strongSelf.readyPromise.set(true)
                    strongSelf.isReadyUpdated()
                }
            }, queue: .mainQueue())
        }
        self.isReadyTimer?.start()
    }
    
    deinit {
        self.isReadyTimer?.invalidate()
    }
    
    override func didLoad() {
        super.didLoad()
        
        if #available(iOS 13.0, *) {
            self.layer.cornerCurve = .continuous
        }
    }
    
    func animateRadialMask(from fromRect: CGRect, to toRect: CGRect) {
        let maskLayer = CAShapeLayer()
        maskLayer.frame = fromRect
        
        let path = CGMutablePath()
        path.addEllipse(in: CGRect(origin: CGPoint(), size: fromRect.size))
        maskLayer.path = path
        
        self.layer.mask = maskLayer
        
        let topLeft = CGPoint(x: 0.0, y: 0.0)
        let topRight = CGPoint(x: self.bounds.width, y: 0.0)
        let bottomLeft = CGPoint(x: 0.0, y: self.bounds.height)
        let bottomRight = CGPoint(x: self.bounds.width, y: self.bounds.height)
        
        func distance(_ v1: CGPoint, _ v2: CGPoint) -> CGFloat {
            let dx = v1.x - v2.x
            let dy = v1.y - v2.y
            return sqrt(dx * dx + dy * dy)
        }
        
        var maxRadius = distance(toRect.center, topLeft)
        maxRadius = max(maxRadius, distance(toRect.center, topRight))
        maxRadius = max(maxRadius, distance(toRect.center, bottomLeft))
        maxRadius = max(maxRadius, distance(toRect.center, bottomRight))
        maxRadius = ceil(maxRadius)
        
        let targetFrame = CGRect(origin: CGPoint(x: toRect.center.x - maxRadius, y: toRect.center.y - maxRadius), size: CGSize(width: maxRadius * 2.0, height: maxRadius * 2.0))
        
        let transition: ContainedViewLayoutTransition = .animated(duration: 0.3, curve: .easeInOut)
        transition.updatePosition(layer: maskLayer, position: targetFrame.center)
        transition.updateTransformScale(layer: maskLayer, scale: maxRadius * 2.0 / fromRect.width, completion: { [weak self] _ in
            self?.layer.mask = nil
        })
    }
    
    func updateLayout(size: CGSize, layoutMode: VideoNodeLayoutMode, transition: ContainedViewLayoutTransition) {
        self.updateLayout(size: size, cornerRadius: self.currentCornerRadius, isOutgoing: true, deviceOrientation: .portrait, isCompactLayout: false, transition: transition)
    }
    
    func updateLayout(size: CGSize, cornerRadius: CGFloat, isOutgoing: Bool, deviceOrientation: UIDeviceOrientation, isCompactLayout: Bool, transition: ContainedViewLayoutTransition) {
        self.currentCornerRadius = cornerRadius
        
        if let placeholderImageNode = self.placeholderImageNode, let image = placeholderImageNode.image {
            let placeholderSize = image.size.aspectFilled(size)
            transition.updateFrame(node: placeholderImageNode, frame: CGRect(origin: CGPoint(x: (size.width - placeholderSize.width) * 0.5, y: (size.height - placeholderSize.height) * 0.5), size: placeholderSize))
        }
        
        var rotationAngle: CGFloat
        if false && isOutgoing && isCompactLayout {
            rotationAngle = CGFloat.pi / 2.0
        } else {
            switch self.currentOrientation {
            case .rotation0:
                rotationAngle = 0.0
            case .rotation90:
                rotationAngle = CGFloat.pi / 2.0
            case .rotation180:
                rotationAngle = CGFloat.pi
            case .rotation270:
                rotationAngle = -CGFloat.pi / 2.0
            }
            
            var additionalAngle: CGFloat = 0.0
            switch deviceOrientation {
            case .portrait:
                additionalAngle = 0.0
            case .landscapeLeft:
                additionalAngle = CGFloat.pi / 2.0
            case .landscapeRight:
                additionalAngle = -CGFloat.pi / 2.0
            case .portraitUpsideDown:
                rotationAngle = CGFloat.pi
            default:
                additionalAngle = 0.0
            }
            rotationAngle += additionalAngle
            if abs(rotationAngle - CGFloat.pi * 3.0 / 2.0) < 0.01 {
                rotationAngle = -CGFloat.pi / 2.0
            }
            if abs(rotationAngle - (-CGFloat.pi)) < 0.01 {
                rotationAngle = -CGFloat.pi + 0.001
            }
        }
        
        let rotateFrame = abs(rotationAngle.remainder(dividingBy: CGFloat.pi)) > 1.0
        let fittingSize: CGSize
        if rotateFrame {
            fittingSize = CGSize(width: size.height, height: size.width)
        } else {
            fittingSize = size
        }
        
        let unboundVideoSize = CGSize(width: self.currentAspect * 10000.0, height: 10000.0)
        
        var fittedVideoSize = unboundVideoSize.fitted(fittingSize)
        if fittedVideoSize.width < fittingSize.width || fittedVideoSize.height < fittingSize.height {
            let isVideoPortrait = unboundVideoSize.width < unboundVideoSize.height
            let isFittingSizePortrait = fittingSize.width < fittingSize.height
            
            if isCompactLayout && isVideoPortrait == isFittingSizePortrait {
                fittedVideoSize = unboundVideoSize.aspectFilled(fittingSize)
            } else {
                let maxFittingEdgeDistance: CGFloat
                if isCompactLayout {
                    maxFittingEdgeDistance = 200.0
                } else {
                    maxFittingEdgeDistance = 400.0
                }
                if fittedVideoSize.width > fittingSize.width - maxFittingEdgeDistance && fittedVideoSize.height > fittingSize.height - maxFittingEdgeDistance {
                    fittedVideoSize = unboundVideoSize.aspectFilled(fittingSize)
                }
            }
        }
        
        let rotatedVideoHeight: CGFloat = max(fittedVideoSize.height, fittedVideoSize.width)
        
        let videoFrame: CGRect = CGRect(origin: CGPoint(), size: fittedVideoSize)
        
        let videoPausedSize = self.videoPausedNode.updateLayout(CGSize(width: size.width - 16.0, height: 100.0))
        transition.updateFrame(node: self.videoPausedNode, frame: CGRect(origin: CGPoint(x: floor((size.width - videoPausedSize.width) / 2.0), y: floor((size.height - videoPausedSize.height) / 2.0)), size: videoPausedSize))
        
        self.videoTransformContainer.bounds = CGRect(origin: CGPoint(), size: videoFrame.size)
        if transition.isAnimated && !videoFrame.height.isZero, let previousVideoHeight = self.previousVideoHeight, !previousVideoHeight.isZero {
            let scaleDifference = previousVideoHeight / rotatedVideoHeight
            if abs(scaleDifference - 1.0) > 0.001 {
                transition.animateTransformScale(node: self.videoTransformContainer, from: scaleDifference, additive: true)
            }
        }
        self.previousVideoHeight = rotatedVideoHeight
        transition.updatePosition(node: self.videoTransformContainer, position: CGPoint(x: size.width / 2.0, y: size.height / 2.0))
        transition.updateTransformRotation(view: self.videoTransformContainer.view, angle: rotationAngle)
        
        let localVideoFrame = CGRect(origin: CGPoint(), size: videoFrame.size)
        self.videoView.view.bounds = localVideoFrame
        self.videoView.view.center = localVideoFrame.center
        // TODO: properly fix the issue
        // On iOS 13 and later metal layer transformation is broken if the layer does not require compositing
        self.videoView.view.alpha = 0.995
        
        if let effectView = self.effectView {
            transition.updateFrame(view: effectView, frame: localVideoFrame)
        }
        
        transition.updateCornerRadius(layer: self.layer, cornerRadius: self.currentCornerRadius)
    }
    
    func updateIsBlurred(isBlurred: Bool, light: Bool = false, animated: Bool = true) {
        if self.hasScheduledUnblur {
            self.hasScheduledUnblur = false
        }
        if self.isBlurred == isBlurred {
            return
        }
        self.isBlurred = isBlurred
        
        if isBlurred {
            if self.effectView == nil {
                let effectView = UIVisualEffectView()
                self.effectView = effectView
                effectView.frame = self.videoTransformContainer.bounds
                self.videoTransformContainer.view.addSubview(effectView)
            }
            if animated {
                UIView.animate(withDuration: 0.3, animations: {
                    self.videoPausedNode.alpha = 1.0
                    self.effectView?.effect = UIBlurEffect(style: light ? .light : .dark)
                })
            } else {
                self.effectView?.effect = UIBlurEffect(style: light ? .light : .dark)
            }
        } else if let effectView = self.effectView {
            self.effectView = nil
            UIView.animate(withDuration: 0.3, animations: {
                self.videoPausedNode.alpha = 0.0
                effectView.effect = nil
            }, completion: { [weak effectView] _ in
                effectView?.removeFromSuperview()
            })
        }
    }
    
    private var hasScheduledUnblur = false
    func flip(withBackground: Bool) {
        if withBackground {
            self.backgroundColor = .black
        }
        UIView.transition(with: withBackground ? self.videoTransformContainer.view : self.view, duration: 0.4, options: [.transitionFlipFromLeft, .curveEaseOut], animations: {
            UIView.performWithoutAnimation {
                self.updateIsBlurred(isBlurred: true, light: false, animated: false)
            }
        }) { finished in
            self.backgroundColor = nil
            self.hasScheduledUnblur = true
            Queue.mainQueue().after(0.5) {
                if self.hasScheduledUnblur {
                    self.updateIsBlurred(isBlurred: false)
                }
            }
        }
    }
}