import Foundation
import UIKit
import Display
import AsyncDisplayKit
import SwiftSignalKit
import Postbox
import TelegramCore
import TelegramPresentationData
import TelegramUIPreferences
import PresentationDataUtils
import AccountContext
import ComponentFlow
import ViewControllerComponent
import MultilineTextComponent
import BalancedTextComponent
import ListSectionComponent
import BundleIconComponent
import LottieComponent
import ListSwitchItemComponent
import ListSwitchItemComponent
import ListActionItemComponent
import Markdown
import TelegramStringFormatting
import MessagePriceItem
import ListItemComponentAdaptor

final class PostSuggestionsSettingsScreenComponent: Component {
    typealias EnvironmentType = ViewControllerComponentContainer.Environment
    
    let context: AccountContext
    let usdWithdrawRate: Int64
    let completion: () -> Void

    init(
        context: AccountContext,
        usdWithdrawRate: Int64,
        completion: @escaping () -> Void
    ) {
        self.context = context
        self.usdWithdrawRate = usdWithdrawRate
        self.completion = completion
    }

    static func ==(lhs: PostSuggestionsSettingsScreenComponent, rhs: PostSuggestionsSettingsScreenComponent) -> Bool {
        return true
    }
    
    private final class ScrollView: UIScrollView {
        override func touchesShouldCancel(in view: UIView) -> Bool {
            return true
        }
    }
    
    final class View: UIView, UIScrollViewDelegate {
        private let topOverscrollLayer = SimpleLayer()
        private let scrollView: ScrollView
        
        private let navigationTitle = ComponentView<Empty>()
        private let icon = ComponentView<Empty>()
        private let subtitle = ComponentView<Empty>()
        private let switchSection = ComponentView<Empty>()
        private let contentSection = ComponentView<Empty>()
        
        private var isUpdating: Bool = false
        
        private var component: PostSuggestionsSettingsScreenComponent?
        private(set) weak var state: EmptyComponentState?
        private var environment: EnvironmentType?
        
        private var areSuggestionsEnabled: Bool = false
        private var starCount: Int = 0
        
        override init(frame: CGRect) {
            self.scrollView = ScrollView()
            self.scrollView.showsVerticalScrollIndicator = true
            self.scrollView.showsHorizontalScrollIndicator = false
            self.scrollView.scrollsToTop = false
            self.scrollView.delaysContentTouches = false
            self.scrollView.canCancelContentTouches = true
            self.scrollView.contentInsetAdjustmentBehavior = .never
            if #available(iOS 13.0, *) {
                self.scrollView.automaticallyAdjustsScrollIndicatorInsets = false
            }
            self.scrollView.alwaysBounceVertical = true
            
            super.init(frame: frame)
            
            self.scrollView.delegate = self
            self.addSubview(self.scrollView)
            
            self.scrollView.layer.addSublayer(self.topOverscrollLayer)
        }
        
        required init?(coder: NSCoder) {
            fatalError("init(coder:) has not been implemented")
        }
        
        deinit {
        }

        func scrollToTop() {
            self.scrollView.setContentOffset(CGPoint(), animated: true)
        }
        
        func attemptNavigation(complete: @escaping () -> Void) -> Bool {
            guard let component = self.component, let environment = self.environment else {
                return true
            }
            
            let _ = component
            let _ = environment
            
            return true
        }
        
        func scrollViewDidScroll(_ scrollView: UIScrollView) {
            self.updateScrolling(transition: .immediate)
        }
        
        var scrolledUp = true
        private func updateScrolling(transition: ComponentTransition) {
            let navigationRevealOffsetY: CGFloat = 0.0
            
            let navigationAlphaDistance: CGFloat = 16.0
            let navigationAlpha: CGFloat = max(0.0, min(1.0, (self.scrollView.contentOffset.y - navigationRevealOffsetY) / navigationAlphaDistance))
            if let controller = self.environment?.controller(), let navigationBar = controller.navigationBar {
                transition.setAlpha(layer: navigationBar.backgroundNode.layer, alpha: navigationAlpha)
                transition.setAlpha(layer: navigationBar.stripeNode.layer, alpha: navigationAlpha)
            }
            
            var scrolledUp = false
            if navigationAlpha < 0.5 {
                scrolledUp = true
            } else if navigationAlpha > 0.5 {
                scrolledUp = false
            }
            
            if self.scrolledUp != scrolledUp {
                self.scrolledUp = scrolledUp
                if !self.isUpdating {
                    self.state?.updated()
                }
            }
            
            if let navigationTitleView = self.navigationTitle.view {
                transition.setAlpha(view: navigationTitleView, alpha: 1.0)
            }
        }
        
        func update(component: PostSuggestionsSettingsScreenComponent, availableSize: CGSize, state: EmptyComponentState, environment: Environment<EnvironmentType>, transition: ComponentTransition) -> CGSize {
            self.isUpdating = true
            defer {
                self.isUpdating = false
            }
            
            if self.component == nil {
                self.starCount = 20
            }
            
            let environment = environment[EnvironmentType.self].value
            let themeUpdated = self.environment?.theme !== environment.theme
            self.environment = environment
            
            self.component = component
            self.state = state
            
            let alphaTransition: ComponentTransition
            if !transition.animation.isImmediate {
                alphaTransition = .easeInOut(duration: 0.25)
            } else {
                alphaTransition = .immediate
            }
            
            if themeUpdated {
                self.backgroundColor = environment.theme.list.blocksBackgroundColor
            }
            
            let presentationData = component.context.sharedContext.currentPresentationData.with { $0 }
            
            //TODO:localize
            let navigationTitleSize = self.navigationTitle.update(
                transition: transition,
                component: AnyComponent(MultilineTextComponent(
                    text: .plain(NSAttributedString(string: "Post Suggestion", font: Font.semibold(17.0), textColor: environment.theme.rootController.navigationBar.primaryTextColor)),
                    horizontalAlignment: .center
                )),
                environment: {},
                containerSize: CGSize(width: availableSize.width, height: 100.0)
            )
            let navigationTitleFrame = CGRect(origin: CGPoint(x: floor((availableSize.width - navigationTitleSize.width) / 2.0), y: environment.statusBarHeight + floor((environment.navigationHeight - environment.statusBarHeight - navigationTitleSize.height) / 2.0)), size: navigationTitleSize)
            if let navigationTitleView = self.navigationTitle.view {
                if navigationTitleView.superview == nil {
                    if let controller = self.environment?.controller(), let navigationBar = controller.navigationBar {
                        navigationBar.view.addSubview(navigationTitleView)
                    }
                }
                transition.setFrame(view: navigationTitleView, frame: navigationTitleFrame)
            }
            
            let bottomContentInset: CGFloat = 24.0
            let sideInset: CGFloat = 16.0 + environment.safeInsets.left
            let sectionSpacing: CGFloat = 24.0
            
            var contentHeight: CGFloat = 0.0
            
            contentHeight += environment.navigationHeight
            
            let iconSize = self.icon.update(
                transition: .immediate,
                component: AnyComponent(LottieComponent(
                    content: LottieComponent.AppBundleContent(name: "LampEmoji"),
                    loop: false
                )),
                environment: {},
                containerSize: CGSize(width: 100.0, height: 100.0)
            )
            let iconFrame = CGRect(origin: CGPoint(x: floor((availableSize.width - iconSize.width) * 0.5), y: contentHeight + 11.0), size: iconSize)
            if let iconView = self.icon.view as? LottieComponent.View {
                if iconView.superview == nil {
                    self.scrollView.addSubview(iconView)
                    iconView.playOnce()
                }
                transition.setPosition(view: iconView, position: iconFrame.center)
                iconView.bounds = CGRect(origin: CGPoint(), size: iconFrame.size)
            }
            
            contentHeight += 129.0
            
            //TODO:localize
            let subtitleString = NSMutableAttributedString(attributedString: parseMarkdownIntoAttributedString("Allow users to suggest posts for your channel.", attributes: MarkdownAttributes(
                body: MarkdownAttributeSet(font: Font.regular(15.0), textColor: environment.theme.list.freeTextColor),
                bold: MarkdownAttributeSet(font: Font.semibold(15.0), textColor: environment.theme.list.freeTextColor),
                link: MarkdownAttributeSet(font: Font.regular(15.0), textColor: environment.theme.list.itemAccentColor),
                linkAttribute: { attributes in
                    return ("URL", "")
                }), textAlignment: .center
            ))
            
            let subtitleSize = self.subtitle.update(
                transition: .immediate,
                component: AnyComponent(BalancedTextComponent(
                    text: .plain(subtitleString),
                    horizontalAlignment: .center,
                    maximumNumberOfLines: 0,
                    lineSpacing: 0.25,
                    highlightColor: environment.theme.list.itemAccentColor.withMultipliedAlpha(0.1),
                    highlightAction: { attributes in
                        if let _ = attributes[NSAttributedString.Key(rawValue: "URL")] {
                            return NSAttributedString.Key(rawValue: "URL")
                        } else {
                            return nil
                        }
                    },
                    tapAction: { [weak self] _, _ in
                        guard let self, let component = self.component else {
                            return
                        }
                        let _ = component
                    }
                )),
                environment: {},
                containerSize: CGSize(width: availableSize.width - sideInset * 2.0, height: 1000.0)
            )
            let subtitleFrame = CGRect(origin: CGPoint(x: floor((availableSize.width - subtitleSize.width) * 0.5), y: contentHeight), size: subtitleSize)
            if let subtitleView = self.subtitle.view {
                if subtitleView.superview == nil {
                    self.scrollView.addSubview(subtitleView)
                }
                transition.setPosition(view: subtitleView, position: subtitleFrame.center)
                subtitleView.bounds = CGRect(origin: CGPoint(), size: subtitleFrame.size)
            }
            contentHeight += subtitleSize.height
            contentHeight += 27.0
            
            var switchSectionItems: [AnyComponentWithIdentity<Empty>] = []
            switchSectionItems.append(AnyComponentWithIdentity(id: 0, component: AnyComponent(ListActionItemComponent(
                theme: environment.theme,
                title: AnyComponent(VStack([
                    AnyComponentWithIdentity(id: AnyHashable(0), component: AnyComponent(MultilineTextComponent(
                        text: .plain(NSAttributedString(
                            string: "Allow Post Suggestions",
                            font: Font.regular(presentationData.listsFontSize.baseDisplaySize),
                            textColor: environment.theme.list.itemPrimaryTextColor
                        )),
                        maximumNumberOfLines: 1
                    ))),
                ], alignment: .left, spacing: 2.0)),
                accessory: .toggle(ListActionItemComponent.Toggle(style: .regular, isOn: self.areSuggestionsEnabled, isInteractive: false)),
                action: { [weak self] _ in
                    guard let self else {
                        return
                    }
                    self.areSuggestionsEnabled = !self.areSuggestionsEnabled
                    self.state?.updated(transition: .spring(duration: 0.4))
                }
            ))))
            
            let switchSectionSize = self.switchSection.update(
                transition: transition,
                component: AnyComponent(ListSectionComponent(
                    theme: environment.theme,
                    header: nil,
                    footer: nil,
                    items: switchSectionItems
                )),
                environment: {},
                containerSize: CGSize(width: availableSize.width - sideInset * 2.0, height: 10000.0)
            )
            let switchSectionFrame = CGRect(origin: CGPoint(x: sideInset, y: contentHeight), size: switchSectionSize)
            if let switchSectionView = self.switchSection.view {
                if switchSectionView.superview == nil {
                    self.scrollView.addSubview(switchSectionView)
                    self.switchSection.parentState = state
                }
                transition.setFrame(view: switchSectionView, frame: switchSectionFrame)
            }
            contentHeight += switchSectionSize.height
            contentHeight += sectionSpacing
            
            var contentSectionItems: [AnyComponentWithIdentity<Empty>] = []
            
            let usdRate = Double(component.usdWithdrawRate) / 1000.0 / 100.0
            let price = self.starCount == 0 ? "" : "≈\(formatTonUsdValue(Int64(self.starCount), divide: false, rate: usdRate, dateTimeFormat: presentationData.dateTimeFormat))"
            
            contentSectionItems.append(AnyComponentWithIdentity(id: 0, component: AnyComponent(ListItemComponentAdaptor(
                itemGenerator: MessagePriceItem(
                    theme: environment.theme,
                    strings: environment.strings,
                    isEnabled: true, minValue: 0, maxValue: 10000,
                    value: Int64(self.starCount),
                    price: price,
                    sectionId: 0,
                    updated: { [weak self] value, _ in
                        guard let self else {
                            return
                        }
                        
                        self.starCount = Int(value)
                        if !self.isUpdating {
                            self.state?.updated(transition: .immediate)
                        }
                    },
                    openSetCustom: { [weak self] in
                        guard let self, let component = self.component, let environment = self.environment else {
                            return
                        }
                        
                        let currentAmount: StarsAmount = StarsAmount(value: Int64(self.starCount), nanos: 0)
                        let starsScreen = component.context.sharedContext.makeStarsWithdrawalScreen(context: component.context, subject: .enterAmount(current: currentAmount, minValue: StarsAmount(value: 0, nanos: 0), fractionAfterCommission: 85, kind: .postSuggestion), completion: { [weak self] amount in
                            guard let self else {
                                return
                            }
                            
                            self.starCount = Int(amount)
                            if !self.isUpdating {
                                self.state?.updated(transition: .immediate)
                            }
                        })
                        environment.controller()?.push(starsScreen)
                    },
                    openPremiumInfo: nil
                ),
                params: ListViewItemLayoutParams(width: availableSize.width - sideInset * 2.0, leftInset: 0.0, rightInset: 0.0, availableHeight: 10000.0, isStandalone: true)
            ))))
            /*contentSectionItems.append(AnyComponentWithIdentity(id: 0, component: AnyComponent(ListItemSliderSelectorComponent(
                theme: environment.theme,
                content: .discrete(ListItemSliderSelectorComponent.Discrete(
                    values: sliderValueList.map { item in
                        return item
                    },
                    markPositions: false,
                    selectedIndex: max(0, min(sliderValueList.count - 1, self.starCount - 1)),
                    title: sliderTitle,
                    secondaryTitle: sliderSecondaryTitle,
                    selectedIndexUpdated: { [weak self] index in
                        guard let self else {
                            return
                        }
                        let index = max(0, min(sliderValueList.count, index))
                        self.starCount = index
                        self.state?.updated(transition: .immediate)
                    }
                ))
            ))))*/
            
            let contentSectionSize = self.contentSection.update(
                transition: transition,
                component: AnyComponent(ListSectionComponent(
                    theme: environment.theme,
                    header: AnyComponent(MultilineTextComponent(
                        text: .plain(NSAttributedString(
                            string: "PRICE FOR EACH SUGGESTION",
                            font: Font.regular(13.0),
                            textColor: environment.theme.list.freeTextColor
                        )),
                        maximumNumberOfLines: 0
                    )),
                    footer: AnyComponent(MultilineTextComponent(
                        text: .plain(NSAttributedString(
                            string: "Charge users for the ability to suggest one post for your channel. You're not required to publish any suggestions by charging this. You'll receive 85% of the selected fee for each incoming suggestion.",
                            font: Font.regular(13.0),
                            textColor: environment.theme.list.freeTextColor
                        )),
                        maximumNumberOfLines: 0
                    )),
                    items: contentSectionItems,
                    displaySeparators: false
                )),
                environment: {},
                containerSize: CGSize(width: availableSize.width - sideInset * 2.0, height: 10000.0)
            )
            let contentSectionFrame = CGRect(origin: CGPoint(x: sideInset, y: contentHeight), size: contentSectionSize)
            if let contentSectionView = self.contentSection.view {
                if contentSectionView.superview == nil {
                    self.scrollView.addSubview(contentSectionView)
                }
                transition.setFrame(view: contentSectionView, frame: contentSectionFrame)
                alphaTransition.setAlpha(view: contentSectionView, alpha: self.areSuggestionsEnabled ? 1.0 : 0.0)
            }
            
            if self.areSuggestionsEnabled {
                contentHeight += contentSectionSize.height
            }
            
            contentHeight += bottomContentInset
            contentHeight += environment.safeInsets.bottom
            
            let previousBounds = self.scrollView.bounds
            
            let contentSize = CGSize(width: availableSize.width, height: contentHeight)
            if self.scrollView.frame != CGRect(origin: CGPoint(), size: availableSize) {
                self.scrollView.frame = CGRect(origin: CGPoint(), size: availableSize)
            }
            if self.scrollView.contentSize != contentSize {
                self.scrollView.contentSize = contentSize
            }
            let scrollInsets = UIEdgeInsets(top: environment.navigationHeight, left: 0.0, bottom: 0.0, right: 0.0)
            if self.scrollView.scrollIndicatorInsets != scrollInsets {
                self.scrollView.scrollIndicatorInsets = scrollInsets
            }
                        
            if !previousBounds.isEmpty, !transition.animation.isImmediate {
                let bounds = self.scrollView.bounds
                if bounds.maxY != previousBounds.maxY {
                    let offsetY = previousBounds.maxY - bounds.maxY
                    transition.animateBoundsOrigin(view: self.scrollView, from: CGPoint(x: 0.0, y: offsetY), to: CGPoint(), additive: true)
                }
            }
            
            self.topOverscrollLayer.frame = CGRect(origin: CGPoint(x: 0.0, y: -3000.0), size: CGSize(width: availableSize.width, height: 3000.0))
            
            self.updateScrolling(transition: transition)
            
            return availableSize
        }
    }
    
    func makeView() -> View {
        return View()
    }
    
    func update(view: View, availableSize: CGSize, state: EmptyComponentState, environment: Environment<EnvironmentType>, transition: ComponentTransition) -> CGSize {
        return view.update(component: self, availableSize: availableSize, state: state, environment: environment, transition: transition)
    }
}

public final class PostSuggestionsSettingsScreen: ViewControllerComponentContainer {
    private let context: AccountContext
    
    public init(
        context: AccountContext,
        completion: @escaping () -> Void
    ) {
        self.context = context
        
        let configuration = StarsSubscriptionConfiguration.with(appConfiguration: context.currentAppConfiguration.with({ $0 }))
        
        super.init(context: context, component: PostSuggestionsSettingsScreenComponent(
            context: context,
            usdWithdrawRate: configuration.usdWithdrawRate,
            completion: completion
        ), navigationBarAppearance: .default, theme: .default, updatedPresentationData: nil)
        
        let presentationData = context.sharedContext.currentPresentationData.with { $0 }
        self.title = ""
        self.navigationItem.backBarButtonItem = UIBarButtonItem(title: presentationData.strings.Common_Back, style: .plain, target: nil, action: nil)
        
        self.scrollToTop = { [weak self] in
            guard let self, let componentView = self.node.hostView.componentView as? PostSuggestionsSettingsScreenComponent.View else {
                return
            }
            componentView.scrollToTop()
        }
        
        self.attemptNavigation = { [weak self] complete in
            guard let self, let componentView = self.node.hostView.componentView as? PostSuggestionsSettingsScreenComponent.View else {
                return true
            }
            
            return componentView.attemptNavigation(complete: complete)
        }
    }
    
    required public init(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    deinit {
    }
    
    @objc private func cancelPressed() {
        self.dismiss()
    }
    
    override public func containerLayoutUpdated(_ layout: ContainerViewLayout, transition: ContainedViewLayoutTransition) {
        super.containerLayoutUpdated(layout, transition: transition)
    }
}