import Foundation
import UIKit
import AsyncDisplayKit
import Display
import Postbox
import TelegramCore
import SyncCore
import SwiftSignalKit
import TelegramPresentationData
import MergeLists
import ActivityIndicator
import AccountContext
import SearchBarNode
import SearchUI
import ContextUI

private final class ChatListControllerNodeView: UITracingLayerView, PreviewingHostView {
    var previewingDelegate: PreviewingHostViewDelegate? {
        return PreviewingHostViewDelegate(controllerForLocation: { [weak self] sourceView, point in
            return self?.controller?.previewingController(from: sourceView, for: point)
        }, commitController: { [weak self] controller in
            self?.controller?.previewingCommit(controller)
        })
    }
    
    weak var controller: ChatListControllerImpl?
}

private struct TestItem: Comparable, Identifiable {
    var value: Int
    var version: Int
    
    var stableId: Int {
        return self.value
    }
    
    static func <(lhs: TestItem, rhs: TestItem) -> Bool {
        if lhs.version != rhs.version {
            return lhs.version < rhs.version
        }
        return lhs.value < rhs.value
    }
}

final class ChatListControllerNode: ASDisplayNode {
    private let context: AccountContext
    private let groupId: PeerGroupId
    private var presentationData: PresentationData
    
    private var chatListEmptyNode: ChatListEmptyNode?
    private var chatListEmptyIndicator: ActivityIndicator?
    let chatListNode: ChatListNode
    var navigationBar: NavigationBar?
    weak var controller: ChatListControllerImpl?
    
    var toolbar: Toolbar?
    private var toolbarNode: ToolbarNode?
    var toolbarActionSelected: ((ToolbarActionOption) -> Void)?
    
    private(set) var searchDisplayController: SearchDisplayController?
    
    private var containerLayout: (ContainerViewLayout, CGFloat, CGFloat)?
    
    var requestDeactivateSearch: (() -> Void)?
    var requestOpenPeerFromSearch: ((Peer, Bool) -> Void)?
    var requestOpenRecentPeerOptions: ((Peer) -> Void)?
    var requestOpenMessageFromSearch: ((Peer, MessageId) -> Void)?
    var requestAddContact: ((String) -> Void)?
    var peerContextAction: ((Peer, ChatListSearchContextActionSource, ASDisplayNode, ContextGesture?) -> Void)?
    var dismissSelf: (() -> Void)?
    var isEmptyUpdated: ((Bool) -> Void)?

    let debugListView = ListView()
    
    init(context: AccountContext, groupId: PeerGroupId, controlsHistoryPreload: Bool, presentationData: PresentationData, controller: ChatListControllerImpl) {
        self.context = context
        self.groupId = groupId
        self.presentationData = presentationData
        
        self.chatListNode = ChatListNode(context: context, groupId: groupId, controlsHistoryPreload: controlsHistoryPreload, mode: .chatList, theme: presentationData.theme, fontSize: presentationData.fontSize, strings: presentationData.strings, dateTimeFormat: presentationData.dateTimeFormat, nameSortOrder: presentationData.nameSortOrder, nameDisplayOrder: presentationData.nameDisplayOrder, disableAnimations: presentationData.disableAnimations)
        
        self.controller = controller
        
        super.init()
        
        self.setViewBlock({
            return ChatListControllerNodeView()
        })
        
        self.backgroundColor = presentationData.theme.chatList.backgroundColor
        
        self.addSubnode(self.chatListNode)
        self.chatListNode.isEmptyUpdated = { [weak self] isEmptyState in
            guard let strongSelf = self else {
                return
            }
            switch isEmptyState {
                case .empty(false):
                    if case .group = strongSelf.groupId {
                        strongSelf.dismissSelf?()
                    } else if strongSelf.chatListEmptyNode == nil {
                        let chatListEmptyNode = ChatListEmptyNode(theme: strongSelf.presentationData.theme, strings: strongSelf.presentationData.strings)
                        strongSelf.chatListEmptyNode = chatListEmptyNode
                        strongSelf.insertSubnode(chatListEmptyNode, belowSubnode: strongSelf.chatListNode)
                        if let (layout, navigationHeight, visualNavigationHeight) = strongSelf.containerLayout {
                            strongSelf.containerLayoutUpdated(layout, navigationBarHeight: navigationHeight, visualNavigationHeight: visualNavigationHeight, transition: .immediate)
                        }
                        strongSelf.isEmptyUpdated?(true)
                    }
                case .notEmpty(false):
                    if case .group = strongSelf.groupId {
                        strongSelf.dismissSelf?()
                    }
                default:
                    if let chatListEmptyNode = strongSelf.chatListEmptyNode {
                        strongSelf.chatListEmptyNode = nil
                        chatListEmptyNode.layer.animateAlpha(from: 1.0, to: 0.0, duration: 0.2, removeOnCompletion: false, completion: { [weak chatListEmptyNode] _ in
                            chatListEmptyNode?.removeFromSupernode()
                        })
                    }
            }
            switch isEmptyState {
                case .empty(true):
                    if strongSelf.chatListEmptyIndicator == nil {
                        let chatListEmptyIndicator = ActivityIndicator(type: .custom(strongSelf.presentationData.theme.list.itemSecondaryTextColor, 22.0, 1.0, false))
                        strongSelf.chatListEmptyIndicator = chatListEmptyIndicator
                        strongSelf.insertSubnode(chatListEmptyIndicator, belowSubnode: strongSelf.chatListNode)
                        if let (layout, navigationHeight, visualNavigationHeight) = strongSelf.containerLayout {
                            strongSelf.containerLayoutUpdated(layout, navigationBarHeight: navigationHeight, visualNavigationHeight: visualNavigationHeight, transition: .immediate)
                        }
                    }
                default:
                    if let chatListEmptyIndicator = strongSelf.chatListEmptyIndicator {
                        strongSelf.chatListEmptyIndicator = nil
                        chatListEmptyIndicator.removeFromSupernode()
                    }
            }
        }
        
        self.addSubnode(self.debugListView)
    }
    
    override func didLoad() {
        super.didLoad()
        
        (self.view as? ChatListControllerNodeView)?.controller = self.controller
    }
    
    func updatePresentationData(_ presentationData: PresentationData) {
        self.presentationData = presentationData
        
        self.backgroundColor = self.presentationData.theme.chatList.backgroundColor
        
        self.chatListNode.updateThemeAndStrings(theme: self.presentationData.theme, fontSize: self.presentationData.fontSize, strings: self.presentationData.strings, dateTimeFormat: self.presentationData.dateTimeFormat, nameSortOrder: self.presentationData.nameSortOrder, nameDisplayOrder: self.presentationData.nameDisplayOrder, disableAnimations: self.presentationData.disableAnimations)
        self.searchDisplayController?.updatePresentationData(presentationData)
        self.chatListEmptyNode?.updateThemeAndStrings(theme: self.presentationData.theme, strings: self.presentationData.strings)
        
        if let toolbarNode = self.toolbarNode {
            toolbarNode.updateTheme(TabBarControllerTheme(rootControllerTheme: self.presentationData.theme))
        }
    }
    
    func containerLayoutUpdated(_ layout: ContainerViewLayout, navigationBarHeight: CGFloat, visualNavigationHeight: CGFloat, transition: ContainedViewLayoutTransition) {
        self.containerLayout = (layout, navigationBarHeight, visualNavigationHeight)
        
        var insets = layout.insets(options: [.input])
        insets.top += navigationBarHeight
        
        insets.left += layout.safeInsets.left
        insets.right += layout.safeInsets.right
        
        if let toolbar = self.toolbar {
            var tabBarHeight: CGFloat
            var options: ContainerViewLayoutInsetOptions = []
            if layout.metrics.widthClass == .regular {
                options.insert(.input)
            }
            let bottomInset: CGFloat = layout.insets(options: options).bottom
            if !layout.safeInsets.left.isZero {
                tabBarHeight = 34.0 + bottomInset
                insets.bottom += 34.0
            } else {
                tabBarHeight = 49.0 + bottomInset
                insets.bottom += 49.0
            }
            
            let tabBarFrame = CGRect(origin: CGPoint(x: 0.0, y: layout.size.height - tabBarHeight), size: CGSize(width: layout.size.width, height: tabBarHeight))
            
            if let toolbarNode = self.toolbarNode {
                transition.updateFrame(node: toolbarNode, frame: tabBarFrame)
                toolbarNode.updateLayout(size: tabBarFrame.size, leftInset: layout.safeInsets.left, rightInset: layout.safeInsets.right,  bottomInset: bottomInset, toolbar: toolbar, transition: transition)
            } else {
                let toolbarNode = ToolbarNode(theme: TabBarControllerTheme(rootControllerTheme: self.presentationData.theme), displaySeparator: true, left: { [weak self] in
                    self?.toolbarActionSelected?(.left)
                }, right: { [weak self] in
                    self?.toolbarActionSelected?(.right)
                }, middle: { [weak self] in
                    self?.toolbarActionSelected?(.middle)
                })
                toolbarNode.frame = tabBarFrame
                toolbarNode.updateLayout(size: tabBarFrame.size, leftInset: layout.safeInsets.left, rightInset: layout.safeInsets.right, bottomInset: bottomInset, toolbar: toolbar, transition: .immediate)
                self.addSubnode(toolbarNode)
                self.toolbarNode = toolbarNode
                if transition.isAnimated {
                    toolbarNode.layer.animateAlpha(from: 0.0, to: 1.0, duration: 0.2)
                }
            }
        } else if let toolbarNode = self.toolbarNode {
            self.toolbarNode = nil
            transition.updateAlpha(node: toolbarNode, alpha: 0.0, completion: { [weak toolbarNode] _ in
                toolbarNode?.removeFromSupernode()
            })
        }
        
        self.chatListNode.bounds = CGRect(x: 0.0, y: 0.0, width: layout.size.width, height: layout.size.height)
        self.chatListNode.position = CGPoint(x: layout.size.width / 2.0, y: layout.size.height / 2.0)
        
        var duration: Double = 0.0
        var curve: UInt = 0
        switch transition {
            case .immediate:
                break
            case let .animated(animationDuration, animationCurve):
                duration = animationDuration
                switch animationCurve {
                    case .easeInOut, .custom:
                        break
                    case .spring:
                        curve = 7
                }
        }
        
        let listViewCurve: ListViewAnimationCurve
        if curve == 7 {
            listViewCurve = .Spring(duration: duration)
        } else {
            listViewCurve = .Default(duration: duration)
        } 
        
        let updateSizeAndInsets = ListViewUpdateSizeAndInsets(size: layout.size, insets: insets, duration: duration, curve: listViewCurve)
        
        self.chatListNode.visualInsets = UIEdgeInsets(top: visualNavigationHeight, left: 0.0, bottom: 0.0, right: 0.0)
        self.chatListNode.updateLayout(transition: transition, updateSizeAndInsets: updateSizeAndInsets)
        
        if let chatListEmptyNode = self.chatListEmptyNode {
            let emptySize = CGSize(width: updateSizeAndInsets.size.width, height: updateSizeAndInsets.size.height - updateSizeAndInsets.insets.top - updateSizeAndInsets.insets.bottom)
            transition.updateFrame(node: chatListEmptyNode, frame: CGRect(origin: CGPoint(x: 0.0, y: updateSizeAndInsets.insets.top), size: emptySize))
            chatListEmptyNode.updateLayout(size: emptySize, transition: transition)
        }
        
        if let chatListEmptyIndicator = self.chatListEmptyIndicator {
            let indicatorSize = chatListEmptyIndicator.measure(CGSize(width: 100.0, height: 100.0))
            transition.updateFrame(node: chatListEmptyIndicator, frame: CGRect(origin: CGPoint(x: floor((layout.size.width - indicatorSize.width) / 2.0), y: updateSizeAndInsets.insets.top + floor((layout.size.height -  updateSizeAndInsets.insets.top - updateSizeAndInsets.insets.bottom - indicatorSize.height) / 2.0)), size: indicatorSize))
        }
        
        if let searchDisplayController = self.searchDisplayController {
            searchDisplayController.containerLayoutUpdated(layout, navigationBarHeight: navigationBarHeight, transition: transition)
        }
    }
    
    func activateSearch(placeholderNode: SearchBarPlaceholderNode) {
        guard let (containerLayout, navigationBarHeight, _) = self.containerLayout, let navigationBar = self.navigationBar, self.searchDisplayController == nil else {
            return
        }
        
        self.searchDisplayController = SearchDisplayController(presentationData: self.presentationData, contentNode: ChatListSearchContainerNode(context: self.context, filter: [], groupId: self.groupId, openPeer: { [weak self] peer, dismissSearch in
            self?.requestOpenPeerFromSearch?(peer, dismissSearch)
        }, openRecentPeerOptions: { [weak self] peer in
            self?.requestOpenRecentPeerOptions?(peer)
        }, openMessage: { [weak self] peer, messageId in
            if let requestOpenMessageFromSearch = self?.requestOpenMessageFromSearch {
                requestOpenMessageFromSearch(peer, messageId)
            }
        }, addContact: { [weak self] phoneNumber in
            if let requestAddContact = self?.requestAddContact {
                requestAddContact(phoneNumber)
            }
        }, peerContextAction: self.peerContextAction), cancel: { [weak self] in
            if let requestDeactivateSearch = self?.requestDeactivateSearch {
                requestDeactivateSearch()
            }
        })
        self.chatListNode.accessibilityElementsHidden = true
        
        self.searchDisplayController?.containerLayoutUpdated(containerLayout, navigationBarHeight: navigationBarHeight, transition: .immediate)
        self.searchDisplayController?.activate(insertSubnode: { [weak self, weak placeholderNode] subnode, isSearchBar in
            if let strongSelf = self, let strongPlaceholderNode = placeholderNode {
                if isSearchBar {
                    strongPlaceholderNode.supernode?.insertSubnode(subnode, aboveSubnode: strongPlaceholderNode)
                } else {
                    strongSelf.insertSubnode(subnode, belowSubnode: navigationBar)
                }
            }
        }, placeholder: placeholderNode)
    }
    
    func deactivateSearch(placeholderNode: SearchBarPlaceholderNode, animated: Bool) {
        if let searchDisplayController = self.searchDisplayController {
            searchDisplayController.deactivate(placeholder: placeholderNode, animated: animated)
            self.searchDisplayController = nil
            self.chatListNode.accessibilityElementsHidden = false
        }
    }
    
    func playArchiveAnimation() {
        self.chatListNode.forEachVisibleItemNode { node in
            if let node = node as? ChatListItemNode {
                node.playArchiveAnimation()
            }
        }
    }
    
    func scrollToTop() {
        if let searchDisplayController = self.searchDisplayController {
            searchDisplayController.contentNode.scrollToTop()
        } else {
            self.chatListNode.scrollToPosition(.top)
        }
    }
}