// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.

using System;
using System.Collections.Generic;
using System.Linq;
using NUnit.Framework;
using osu.Framework.Allocation;
using osu.Framework.Bindables;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using osu.Framework.Graphics.UserInterface;
using osu.Framework.Input;
using osu.Framework.Platform;
using osu.Framework.Testing;
using osu.Game.Graphics.UserInterface;
using osu.Game.Online.API;
using osu.Game.Online.API.Requests;
using osu.Game.Online.Chat;
using osu.Game.Overlays;
using osu.Game.Overlays.Chat.Selection;
using osu.Game.Overlays.Chat.Tabs;
using osu.Game.Users;
using osuTK.Input;

namespace osu.Game.Tests.Visual.Online
{
    public class TestSceneChatOverlay : OsuManualInputManagerTestScene
    {
        private TestChatOverlay chatOverlay;
        private ChannelManager channelManager;

        private IEnumerable<Channel> visibleChannels => chatOverlay.ChannelTabControl.VisibleItems.Where(channel => channel.Name != "+");
        private IEnumerable<Channel> joinedChannels => chatOverlay.ChannelTabControl.Items.Where(channel => channel.Name != "+");
        private readonly List<Channel> channels;

        private Channel currentChannel => channelManager.CurrentChannel.Value;
        private Channel nextChannel => joinedChannels.ElementAt(joinedChannels.ToList().IndexOf(currentChannel) + 1);
        private Channel previousChannel => joinedChannels.ElementAt(joinedChannels.ToList().IndexOf(currentChannel) - 1);
        private Channel channel1 => channels[0];
        private Channel channel2 => channels[1];
        private Channel channel3 => channels[2];

        [Resolved]
        private GameHost host { get; set; }

        public TestSceneChatOverlay()
        {
            channels = Enumerable.Range(1, 10)
                                 .Select(index => new Channel(new User())
                                 {
                                     Name = $"Channel no. {index}",
                                     Topic = index == 3 ? null : $"We talk about the number {index} here",
                                     Type = index % 2 == 0 ? ChannelType.PM : ChannelType.Temporary,
                                     Id = index
                                 })
                                 .ToList();
        }

        [SetUp]
        public void Setup()
        {
            Schedule(() =>
            {
                ChannelManagerContainer container;

                Child = container = new ChannelManagerContainer(channels)
                {
                    RelativeSizeAxes = Axes.Both,
                };

                chatOverlay = container.ChatOverlay;
                channelManager = container.ChannelManager;
            });
        }

        [SetUpSteps]
        public void SetUpSteps()
        {
            AddStep("register request handling", () =>
            {
                ((DummyAPIAccess)API).HandleRequest = req =>
                {
                    switch (req)
                    {
                        case JoinChannelRequest joinChannel:
                            joinChannel.TriggerSuccess();
                            return true;

                        case GetUserRequest getUser:
                            if (getUser.Lookup.Equals("some body", StringComparison.OrdinalIgnoreCase))
                            {
                                getUser.TriggerSuccess(new User
                                {
                                    Username = "some body",
                                    Id = 1,
                                });
                            }
                            else
                            {
                                getUser.TriggerFailure(new Exception());
                            }

                            return true;
                    }

                    return false;
                };
            });
        }

        [Test]
        public void TestHideOverlay()
        {
            AddAssert("Chat overlay is visible", () => chatOverlay.State.Value == Visibility.Visible);
            AddAssert("Selector is visible", () => chatOverlay.SelectionOverlayState == Visibility.Visible);

            AddStep("Close chat overlay", () => chatOverlay.Hide());

            AddAssert("Chat overlay was hidden", () => chatOverlay.State.Value == Visibility.Hidden);
            AddAssert("Channel selection overlay was hidden", () => chatOverlay.SelectionOverlayState == Visibility.Hidden);
        }

        [Test]
        public void TestSelectingChannelClosesSelector()
        {
            AddAssert("Selector is visible", () => chatOverlay.SelectionOverlayState == Visibility.Visible);

            AddStep("Join channel 1", () => channelManager.JoinChannel(channel1));
            AddStep("Switch to channel 1", () => clickDrawable(chatOverlay.TabMap[channel1]));

            AddAssert("Current channel is channel 1", () => currentChannel == channel1);
            AddAssert("Channel selector was closed", () => chatOverlay.SelectionOverlayState == Visibility.Hidden);
        }

        [Test]
        public void TestSearchInSelector()
        {
            AddStep("Search for 'no. 2'", () => chatOverlay.ChildrenOfType<SearchTextBox>().First().Text = "no. 2");
            AddUntilStep("Only channel 2 visible", () =>
            {
                var listItems = chatOverlay.ChildrenOfType<ChannelListItem>().Where(c => c.IsPresent);
                return listItems.Count() == 1 && listItems.Single().Channel == channel2;
            });
        }

        [Test]
        public void TestChannelShortcutKeys()
        {
            AddStep("Join channels", () => channels.ForEach(channel => channelManager.JoinChannel(channel)));
            AddStep("Close channel selector", () => InputManager.Key(Key.Escape));
            AddUntilStep("Wait for close", () => chatOverlay.SelectionOverlayState == Visibility.Hidden);

            for (int zeroBasedIndex = 0; zeroBasedIndex < 10; ++zeroBasedIndex)
            {
                var oneBasedIndex = zeroBasedIndex + 1;
                var targetNumberKey = oneBasedIndex % 10;
                var targetChannel = channels[zeroBasedIndex];
                AddStep($"Press Alt+{targetNumberKey}", () => pressChannelHotkey(targetNumberKey));
                AddAssert($"Channel #{oneBasedIndex} is selected", () => currentChannel == targetChannel);
            }
        }

        private Channel expectedChannel;

        [Test]
        public void TestCloseChannelBehaviour()
        {
            AddUntilStep("Join until dropdown has channels", () =>
            {
                if (visibleChannels.Count() < joinedChannels.Count())
                    return true;

                // Using temporary channels because they don't hide their names when not active
                channelManager.JoinChannel(new Channel
                {
                    Name = $"Channel no. {joinedChannels.Count() + 11}",
                    Type = ChannelType.Temporary
                });

                return false;
            });

            AddStep("Switch to last tab", () => clickDrawable(chatOverlay.TabMap[visibleChannels.Last()]));
            AddAssert("Last visible selected", () => currentChannel == visibleChannels.Last());

            // Closing the last channel before dropdown
            AddStep("Close current channel", () =>
            {
                expectedChannel = nextChannel;
                chatOverlay.ChannelTabControl.RemoveChannel(currentChannel);
            });
            AddAssert("Next channel selected", () => currentChannel == expectedChannel);
            AddAssert("Selector remained closed", () => chatOverlay.SelectionOverlayState == Visibility.Hidden);

            // Depending on the window size, one more channel might need to be closed for the selectorTab to appear
            AddUntilStep("Close channels until selector visible", () =>
            {
                if (chatOverlay.ChannelTabControl.VisibleItems.Last().Name == "+")
                    return true;

                chatOverlay.ChannelTabControl.RemoveChannel(visibleChannels.Last());
                return false;
            });
            AddAssert("Last visible selected", () => currentChannel == visibleChannels.Last());

            // Closing the last channel with dropdown no longer present
            AddStep("Close last when selector next", () =>
            {
                expectedChannel = previousChannel;
                chatOverlay.ChannelTabControl.RemoveChannel(currentChannel);
            });
            AddAssert("Previous channel selected", () => currentChannel == expectedChannel);

            // Standard channel closing
            AddStep("Switch to previous channel", () => chatOverlay.ChannelTabControl.SwitchTab(-1));
            AddStep("Close current channel", () =>
            {
                expectedChannel = nextChannel;
                chatOverlay.ChannelTabControl.RemoveChannel(currentChannel);
            });
            AddAssert("Next channel selected", () => currentChannel == expectedChannel);

            // Selector reappearing after all channels closed
            AddUntilStep("Close all channels", () =>
            {
                if (!joinedChannels.Any())
                    return true;

                chatOverlay.ChannelTabControl.RemoveChannel(joinedChannels.Last());
                return false;
            });
            AddAssert("Selector is visible", () => chatOverlay.SelectionOverlayState == Visibility.Visible);
        }

        [Test]
        public void TestChannelCloseButton()
        {
            AddStep("Join 2 channels", () =>
            {
                channelManager.JoinChannel(channel1);
                channelManager.JoinChannel(channel2);
            });

            // PM channel close button only appears when active
            AddStep("Select PM channel", () => clickDrawable(chatOverlay.TabMap[channel2]));
            AddStep("Click PM close button", () => clickDrawable(((TestPrivateChannelTabItem)chatOverlay.TabMap[channel2]).CloseButton.Child));
            AddAssert("PM channel closed", () => !channelManager.JoinedChannels.Contains(channel2));

            // Non-PM chat channel close button only appears when hovered
            AddStep("Hover normal channel tab", () => InputManager.MoveMouseTo(chatOverlay.TabMap[channel1]));
            AddStep("Click normal close button", () => clickDrawable(((TestChannelTabItem)chatOverlay.TabMap[channel1]).CloseButton.Child));
            AddAssert("All channels closed", () => !channelManager.JoinedChannels.Any());
        }

        [Test]
        public void TestCloseTabShortcut()
        {
            AddStep("Join 2 channels", () =>
            {
                channelManager.JoinChannel(channel1);
                channelManager.JoinChannel(channel2);
            });

            // Want to close channel 2
            AddStep("Select channel 2", () => clickDrawable(chatOverlay.TabMap[channel2]));
            AddStep("Close tab via shortcut", pressCloseDocumentKeys);

            // Channel 2 should be closed
            AddAssert("Channel 1 open", () => channelManager.JoinedChannels.Contains(channel1));
            AddAssert("Channel 2 closed", () => !channelManager.JoinedChannels.Contains(channel2));

            // Want to close channel 1
            AddStep("Select channel 1", () => clickDrawable(chatOverlay.TabMap[channel1]));

            AddStep("Close tab via shortcut", pressCloseDocumentKeys);
            // Channel 1 and channel 2 should be closed
            AddAssert("All channels closed", () => !channelManager.JoinedChannels.Any());
        }

        [Test]
        public void TestNewTabShortcut()
        {
            AddStep("Join 2 channels", () =>
            {
                channelManager.JoinChannel(channel1);
                channelManager.JoinChannel(channel2);
            });

            // Want to join another channel
            AddStep("Press new tab shortcut", pressNewTabKeys);

            // Selector should be visible
            AddAssert("Selector is visible", () => chatOverlay.SelectionOverlayState == Visibility.Visible);
        }

        [Test]
        public void TestRestoreTabShortcut()
        {
            AddStep("Join 3 channels", () =>
            {
                channelManager.JoinChannel(channel1);
                channelManager.JoinChannel(channel2);
                channelManager.JoinChannel(channel3);
            });

            // Should do nothing
            AddStep("Restore tab via shortcut", pressRestoreTabKeys);
            AddAssert("All channels still open", () => channelManager.JoinedChannels.Count == 3);

            // Close channel 1
            AddStep("Select channel 1", () => clickDrawable(chatOverlay.TabMap[channel1]));
            AddStep("Click normal close button", () => clickDrawable(((TestChannelTabItem)chatOverlay.TabMap[channel1]).CloseButton.Child));
            AddAssert("Channel 1 closed", () => !channelManager.JoinedChannels.Contains(channel1));
            AddAssert("Other channels still open", () => channelManager.JoinedChannels.Count == 2);

            // Reopen channel 1
            AddStep("Restore tab via shortcut", pressRestoreTabKeys);
            AddAssert("All channels now open", () => channelManager.JoinedChannels.Count == 3);
            AddAssert("Current channel is channel 1", () => currentChannel == channel1);

            // Close two channels
            AddStep("Select channel 1", () => clickDrawable(chatOverlay.TabMap[channel1]));
            AddStep("Close channel 1", () => clickDrawable(((TestChannelTabItem)chatOverlay.TabMap[channel1]).CloseButton.Child));
            AddStep("Select channel 2", () => clickDrawable(chatOverlay.TabMap[channel2]));
            AddStep("Close channel 2", () => clickDrawable(((TestPrivateChannelTabItem)chatOverlay.TabMap[channel2]).CloseButton.Child));
            AddAssert("Only one channel open", () => channelManager.JoinedChannels.Count == 1);
            AddAssert("Current channel is channel 3", () => currentChannel == channel3);

            // Should first re-open channel 2
            AddStep("Restore tab via shortcut", pressRestoreTabKeys);
            AddAssert("Channel 1 still closed", () => !channelManager.JoinedChannels.Contains(channel1));
            AddAssert("Channel 2 now open", () => channelManager.JoinedChannels.Contains(channel2));
            AddAssert("Current channel is channel 2", () => currentChannel == channel2);

            // Should then re-open channel 1
            AddStep("Restore tab via shortcut", pressRestoreTabKeys);
            AddAssert("All channels now open", () => channelManager.JoinedChannels.Count == 3);
            AddAssert("Current channel is channel 1", () => currentChannel == channel1);
        }

        [Test]
        public void TestChatCommand()
        {
            AddStep("Join channel 1", () => channelManager.JoinChannel(channel1));
            AddStep("Select channel 1", () => clickDrawable(chatOverlay.TabMap[channel1]));

            AddStep("Open chat with user", () => channelManager.PostCommand("chat some body"));
            AddAssert("PM channel is selected", () =>
                channelManager.CurrentChannel.Value.Type == ChannelType.PM && channelManager.CurrentChannel.Value.Users.Single().Username == "some body");

            AddStep("Open chat with non-existent user", () => channelManager.PostCommand("chat nobody"));
            AddAssert("Last message is error", () => channelManager.CurrentChannel.Value.Messages.Last() is ErrorMessage);

            // Make sure no unnecessary requests are made when the PM channel is already open.
            AddStep("Select channel 1", () => clickDrawable(chatOverlay.TabMap[channel1]));
            AddStep("Unregister request handling", () => ((DummyAPIAccess)API).HandleRequest = null);
            AddStep("Open chat with user", () => channelManager.PostCommand("chat some body"));
            AddAssert("PM channel is selected", () =>
                channelManager.CurrentChannel.Value.Type == ChannelType.PM && channelManager.CurrentChannel.Value.Users.Single().Username == "some body");
        }

        private void pressChannelHotkey(int number)
        {
            var channelKey = Key.Number0 + number;
            InputManager.PressKey(Key.AltLeft);
            InputManager.Key(channelKey);
            InputManager.ReleaseKey(Key.AltLeft);
        }

        private void pressCloseDocumentKeys() => InputManager.Keys(PlatformAction.DocumentClose);

        private void pressNewTabKeys() => InputManager.Keys(PlatformAction.TabNew);

        private void pressRestoreTabKeys() => InputManager.Keys(PlatformAction.TabRestore);

        private void clickDrawable(Drawable d)
        {
            InputManager.MoveMouseTo(d);
            InputManager.Click(MouseButton.Left);
        }

        private class ChannelManagerContainer : Container
        {
            public TestChatOverlay ChatOverlay { get; private set; }

            [Cached]
            public ChannelManager ChannelManager { get; } = new ChannelManager();

            private readonly List<Channel> channels;

            public ChannelManagerContainer(List<Channel> channels)
            {
                this.channels = channels;
            }

            [BackgroundDependencyLoader]
            private void load()
            {
                ((BindableList<Channel>)ChannelManager.AvailableChannels).AddRange(channels);

                InternalChildren = new Drawable[]
                {
                    ChannelManager,
                    ChatOverlay = new TestChatOverlay { RelativeSizeAxes = Axes.Both, },
                };

                ChatOverlay.Show();
            }
        }

        private class TestChatOverlay : ChatOverlay
        {
            public Visibility SelectionOverlayState => ChannelSelectionOverlay.State.Value;

            public new ChannelTabControl ChannelTabControl => base.ChannelTabControl;

            public new ChannelSelectionOverlay ChannelSelectionOverlay => base.ChannelSelectionOverlay;

            protected override ChannelTabControl CreateChannelTabControl() => new TestTabControl();

            public IReadOnlyDictionary<Channel, TabItem<Channel>> TabMap => ((TestTabControl)ChannelTabControl).TabMap;
        }

        private class TestTabControl : ChannelTabControl
        {
            protected override TabItem<Channel> CreateTabItem(Channel value)
            {
                switch (value.Type)
                {
                    case ChannelType.PM:
                        return new TestPrivateChannelTabItem(value);

                    default:
                        return new TestChannelTabItem(value);
                }
            }

            public new IReadOnlyDictionary<Channel, TabItem<Channel>> TabMap => base.TabMap;
        }

        private class TestChannelTabItem : ChannelTabItem
        {
            public TestChannelTabItem(Channel channel)
                : base(channel)
            {
            }

            public new ClickableContainer CloseButton => base.CloseButton;
        }

        private class TestPrivateChannelTabItem : PrivateChannelTabItem
        {
            public TestPrivateChannelTabItem(Channel channel)
                : base(channel)
            {
            }

            public new ClickableContainer CloseButton => base.CloseButton;
        }
    }
}