// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using osu.Framework.Allocation;
using osu.Framework.Extensions.IEnumerableExtensions;
using osu.Framework.Graphics;
using osu.Framework.Graphics.Containers;
using osu.Framework.Graphics.Sprites;
using osu.Framework.MathUtils;
using osu.Framework.Screens;
using osu.Game.Graphics;
using osu.Game.Graphics.Containers;
using osu.Game.Graphics.Sprites;
using osu.Game.Graphics.UserInterface;
using osu.Game.Online.API;
using osu.Game.Overlays.Settings;
using osuTK;
using osuTK.Graphics;

namespace osu.Game.Overlays.AccountCreation
{
    public class ScreenEntry : AccountCreationScreen
    {
        private ErrorTextFlowContainer usernameDescription;
        private ErrorTextFlowContainer emailAddressDescription;
        private ErrorTextFlowContainer passwordDescription;

        private OsuTextBox usernameTextBox;
        private OsuTextBox emailTextBox;
        private OsuPasswordTextBox passwordTextBox;

        private APIAccess api;
        private ShakeContainer registerShake;
        private IEnumerable<SpriteText> characterCheckText;

        protected override void OnEntering(Screen last)
        {
            base.OnEntering(last);

            var nextTextbox = nextUnfilledTextbox();
            if (nextTextbox != null)
                Schedule(() => GetContainingInputManager().ChangeFocus(nextTextbox));
        }

        [BackgroundDependencyLoader]
        private void load(OsuColour colours, APIAccess api)
        {
            this.api = api;

            Child = new FillFlowContainer
            {
                RelativeSizeAxes = Axes.Both,
                Direction = FillDirection.Vertical,
                Anchor = Anchor.TopCentre,
                Origin = Anchor.TopCentre,
                Padding = new MarginPadding(20),
                Spacing = new Vector2(0, 10),
                Children = new Drawable[]
                {
                    new OsuSpriteText
                    {
                        TextSize = 20,
                        Margin = new MarginPadding { Vertical = 10 },
                        Anchor = Anchor.TopCentre,
                        Origin = Anchor.TopCentre,
                        Text = "Let's create an account!",
                    },
                    usernameTextBox = new OsuTextBox
                    {
                        PlaceholderText = "username",
                        RelativeSizeAxes = Axes.X,
                        TabbableContentContainer = this
                    },
                    usernameDescription = new ErrorTextFlowContainer
                    {
                        RelativeSizeAxes = Axes.X,
                        AutoSizeAxes = Axes.Y
                    },
                    emailTextBox = new OsuTextBox
                    {
                        PlaceholderText = "email address",
                        RelativeSizeAxes = Axes.X,
                        TabbableContentContainer = this
                    },
                    emailAddressDescription = new ErrorTextFlowContainer
                    {
                        RelativeSizeAxes = Axes.X,
                        AutoSizeAxes = Axes.Y
                    },
                    passwordTextBox = new OsuPasswordTextBox
                    {
                        PlaceholderText = "password",
                        RelativeSizeAxes = Axes.X,
                        TabbableContentContainer = this,
                    },
                    passwordDescription = new ErrorTextFlowContainer
                    {
                        RelativeSizeAxes = Axes.X,
                        AutoSizeAxes = Axes.Y
                    },
                    new Container
                    {
                        RelativeSizeAxes = Axes.X,
                        AutoSizeAxes = Axes.Y,
                        Children = new Drawable[]
                        {
                            registerShake = new ShakeContainer
                            {
                                RelativeSizeAxes = Axes.X,
                                AutoSizeAxes = Axes.Y,
                                Child = new SettingsButton
                                {
                                    Text = "Register",
                                    Margin = new MarginPadding { Vertical = 20 },
                                    Action = performRegistration
                                }
                            }
                        }
                    },
                }
            };

            usernameDescription.AddText("This will be your public presence. No profanity, no impersonation. Avoid exposing your own personal details, too!");

            emailAddressDescription.AddText("Will be used for notifications, account verification and in the case you forget your password. No spam, ever.");
            emailAddressDescription.AddText(" Make sure to get it right!", cp => cp.Font = "Exo2.0-Bold");

            passwordDescription.AddText("At least ");
            characterCheckText = passwordDescription.AddText("8 characters long");
            passwordDescription.AddText(". Choose something long but also something you will remember, like a line from your favourite song.");

            passwordTextBox.Current.ValueChanged += text => { characterCheckText.ForEach(s => s.Colour = text.Length == 0 ? Color4.White : Interpolation.ValueAt(text.Length, Color4.OrangeRed, Color4.YellowGreen, 0, 8, Easing.In)); };
        }

        private void performRegistration()
        {
            var textbox = nextUnfilledTextbox();

            if (textbox != null)
            {
                Schedule(() => GetContainingInputManager().ChangeFocus(textbox));
                registerShake.Shake();
                return;
            }

            usernameDescription.ClearErrors();
            emailAddressDescription.ClearErrors();
            passwordDescription.ClearErrors();

            Task.Run(() =>
            {
                bool success;
                RegistrationRequest.RegistrationRequestErrors errors = null;

                try
                {
                    errors = api.CreateAccount(emailTextBox.Text, usernameTextBox.Text, passwordTextBox.Text);
                    success = errors == null;
                }
                catch (Exception)
                {
                    success = false;
                }

                Schedule(() =>
                {
                    if (!success)
                    {
                        if (errors != null)
                        {
                            usernameDescription.AddErrors(errors.User.Username);
                            emailAddressDescription.AddErrors(errors.User.Email);
                            passwordDescription.AddErrors(errors.User.Password);
                        }
                        else
                        {
                            passwordDescription.AddErrors(new[] { "Something happened... but we're not sure what." });
                        }

                        registerShake.Shake();
                        return;
                    }

                    api.Login(emailTextBox.Text, passwordTextBox.Text);
                });
            });
        }

        private OsuTextBox nextUnfilledTextbox()
        {
            OsuTextBox textboxIfUsable(OsuTextBox textbox)
            {
                return !string.IsNullOrEmpty(textbox.Text) ? null : textbox;
            }

            return textboxIfUsable(usernameTextBox) ?? textboxIfUsable(emailTextBox) ?? textboxIfUsable(passwordTextBox);
        }
    }
}