namespace Zcbot.WindowsNode;

internal sealed class ConfigurationForm : Form
{
    private const int ContentWidth = 800;

    private readonly TextBox server = CreateTextBox("http://127.0.0.1:8765");
    private readonly TextBox nodeName = CreateTextBox(Environment.MachineName.ToLowerInvariant());
    private readonly TextBox enrollmentCode = CreateTextBox(usePassword: true);
    private readonly Button register = CreateButton("注册并连接", 128, primary: true);
    private readonly Button resetIdentity = CreateButton("清除本机身份并重新注册", 220);
    private readonly CheckBox startAtLogin = new()
    {
        Text = "登录 Windows 后自动启动节点",
        AutoSize = true,
        Margin = new Padding(0, 4, 0, 8),
    };
    private readonly Label state = new()
    {
        AutoSize = true,
        Font = new Font("Microsoft YaHei UI", 13, FontStyle.Bold),
        Margin = new Padding(0, 2, 0, 5),
    };
    private readonly Label detail = CreateBodyLabel();
    private readonly Label identity = CreateBodyLabel();
    private readonly Label capabilitySummary = CreateBodyLabel();
    private readonly TableLayoutPanel registrationCard;
    private readonly TableLayoutPanel registeredActionsCard;
    private bool changingStartup;

    internal event Func<EnrollOptions, Task>? RegisterRequested;
    internal event Action? ResetIdentityRequested;

    internal ConfigurationForm()
    {
        Text = "zcbot Windows Node";
        AutoScaleMode = AutoScaleMode.Dpi;
        ClientSize = new Size(880, 720);
        MinimumSize = new Size(850, 680);
        StartPosition = FormStartPosition.CenterScreen;
        Font = new Font("Microsoft YaHei UI", 9);
        FormBorderStyle = FormBorderStyle.Sizable;
        BackColor = Color.FromArgb(241, 245, 249);

        var shell = new TableLayoutPanel
        {
            Dock = DockStyle.Fill,
            AutoScroll = true,
            ColumnCount = 3,
            RowCount = 1,
            Padding = new Padding(0, 22, 0, 22),
            BackColor = BackColor,
        };
        shell.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));
        shell.ColumnStyles.Add(new ColumnStyle(SizeType.Absolute, ContentWidth));
        shell.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));
        Controls.Add(shell);

        var page = new TableLayoutPanel
        {
            AutoSize = true,
            AutoSizeMode = AutoSizeMode.GrowAndShrink,
            Dock = DockStyle.Top,
            ColumnCount = 1,
            RowCount = 6,
            BackColor = BackColor,
        };
        page.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100));
        shell.Controls.Add(page, 1, 0);

        var heading = new TableLayoutPanel
        {
            AutoSize = true,
            Dock = DockStyle.Top,
            ColumnCount = 1,
            Margin = new Padding(4, 0, 4, 18),
        };
        heading.Controls.Add(new Label
        {
            Text = "zcbot Windows Node",
            AutoSize = true,
            Font = new Font("Microsoft YaHei UI", 20, FontStyle.Bold),
            ForeColor = Color.FromArgb(15, 23, 42),
        });
        heading.Controls.Add(CreateHint("连接本机科研软件与 zcbot 的受控执行节点"));
        page.Controls.Add(heading);

        var overview = new TableLayoutPanel
        {
            AutoSize = true,
            Dock = DockStyle.Top,
            ColumnCount = 2,
            Margin = new Padding(0, 0, 0, 14),
        };
        overview.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));
        overview.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));

        var statusCard = CreateCard();
        statusCard.Margin = new Padding(0, 0, 7, 0);
        statusCard.Controls.Add(CreateSectionTitle("节点状态"));
        statusCard.Controls.Add(state);
        statusCard.Controls.Add(detail);
        statusCard.Controls.Add(identity);
        overview.Controls.Add(statusCard, 0, 0);

        var capabilityCard = CreateCard();
        capabilityCard.Margin = new Padding(7, 0, 0, 0);
        capabilityCard.Controls.Add(CreateSectionTitle("节点能力"));
        capabilityCard.Controls.Add(CreateCapabilityBadge("Origin 绘图", "origin.plot@v1"));
        capabilityCard.Controls.Add(capabilitySummary);
        capabilityCard.Controls.Add(CreateHint(
            "当前 MVP 内置声明该协议，不需要手工配置；它不代表已完成 Origin 安装检测。"));
        overview.Controls.Add(capabilityCard, 1, 0);
        page.Controls.Add(overview);

        registrationCard = CreateCard();
        registrationCard.Controls.Add(CreateSectionTitle("首次注册"));
        registrationCard.Controls.Add(CreateHint(
            "从 zcbot 管理后台生成注册码。注册码默认 10 分钟有效，成功注册一次后立即失效。"));
        AddField(registrationCard, "zcbot 服务地址", server, "云端填写站点根地址；本机测试使用 http://127.0.0.1:8765");
        AddField(registrationCard, "节点名称", nodeName, "必须与注册码限定的节点名称完全一致");
        AddField(registrationCard, "一次性注册码", enrollmentCode, "格式类似 ZCN-…；仅用于首次注册，不会长期保存");
        var registerActions = CreateActions();
        registerActions.Controls.Add(register);
        registrationCard.Controls.Add(registerActions);
        page.Controls.Add(registrationCard);

        registeredActionsCard = CreateCard();
        registeredActionsCard.Controls.Add(CreateSectionTitle("节点身份"));
        registeredActionsCard.Controls.Add(CreateHint(
            "服务地址、节点名称和能力在首次注册时确定。需要修改时，请先在管理后台删除旧节点，再清除本机身份并重新注册。"));
        var identityActions = CreateActions();
        identityActions.Controls.Add(resetIdentity);
        registeredActionsCard.Controls.Add(identityActions);
        page.Controls.Add(registeredActionsCard);

        var runtimeCard = CreateCard();
        runtimeCard.Controls.Add(CreateSectionTitle("运行设置"));
        runtimeCard.Controls.Add(startAtLogin);
        runtimeCard.Controls.Add(CreateHint(
            "关闭此窗口后，节点仍在系统托盘运行。右键托盘图标可以立即重连或退出。"));
        page.Controls.Add(runtimeCard);

        var securityNote = CreateHint(
            "安全说明：Node Token 由 Windows DPAPI 加密保存，不在界面显示，也不会写入日志。");
        securityNote.Margin = new Padding(4, 8, 4, 0);
        page.Controls.Add(securityNote);

        register.Click += async (_, _) => await RegisterAsync();
        resetIdentity.Click += (_, _) => ResetIdentity();
        startAtLogin.CheckedChanged += (_, _) => ToggleStartup();
        FormClosing += (_, eventArgs) =>
        {
            if (eventArgs.CloseReason == CloseReason.UserClosing)
            {
                eventArgs.Cancel = true;
                Hide();
            }
        };
        startAtLogin.Checked = StartupRegistration.IsEnabled;
        ApplyStatus(NodeStatus.Create(NodeState.NotRegistered, "尚未注册"), null);
    }

    internal void ApplyStatus(NodeStatus status, NodeConfig? config)
    {
        state.Text = status.State switch
        {
            NodeState.Online => "● 在线",
            NodeState.Connecting => "● 正在连接",
            NodeState.NotRegistered => "● 尚未注册",
            NodeState.AuthenticationRequired => "● 需要重新注册",
            NodeState.Offline => "● 离线",
            _ => "● 已停止",
        };
        state.ForeColor = status.State switch
        {
            NodeState.Online => Color.ForestGreen,
            NodeState.Connecting => Color.DarkOrange,
            NodeState.NotRegistered or NodeState.AuthenticationRequired => Color.Firebrick,
            _ => Color.DimGray,
        };
        detail.Text = $"{status.Message}　{status.ChangedAt:HH:mm:ss}";
        identity.Text = config is null
            ? "尚未建立节点身份"
            : $"节点：{config.NodeName}\nNode ID：{config.NodeId}\n服务：{config.ServerUrl}";
        capabilitySummary.Text = config is null
            ? "注册后启用"
            : $"已声明 {config.Capabilities.Count} 项能力";

        var registered = config is not null;
        registrationCard.Visible = !registered;
        registeredActionsCard.Visible = registered;
        register.Enabled = !registered && status.State != NodeState.Connecting;
        if (registered)
        {
            server.Text = config!.ServerUrl.AbsoluteUri.TrimEnd('/');
            nodeName.Text = config.NodeName;
            enrollmentCode.Clear();
        }
    }

    private void ResetIdentity()
    {
        var answer = MessageBox.Show(
            "这会删除本机加密身份，随后需要使用新注册码重新注册。请先在管理后台删除或禁用云端旧节点。是否继续？",
            "清除本机节点身份", MessageBoxButtons.YesNo, MessageBoxIcon.Warning,
            MessageBoxDefaultButton.Button2);
        if (answer == DialogResult.Yes)
        {
            ResetIdentityRequested?.Invoke();
        }
    }

    private async Task RegisterAsync()
    {
        if (RegisterRequested is null)
        {
            return;
        }
        try
        {
            register.Enabled = false;
            detail.Text = "正在注册…";
            var options = EnrollOptions.Parse([
                "--server", server.Text, "--name", nodeName.Text, "--code", enrollmentCode.Text]);
            await RegisterRequested(options);
        }
        catch (Exception exception) when (exception is NodeConfigurationException or HttpRequestException)
        {
            MessageBox.Show(exception.Message, "注册失败", MessageBoxButtons.OK, MessageBoxIcon.Error);
            register.Enabled = true;
        }
    }

    private void ToggleStartup()
    {
        if (changingStartup)
        {
            return;
        }
        try
        {
            StartupRegistration.SetEnabled(startAtLogin.Checked);
        }
        catch (Exception exception) when (exception is UnauthorizedAccessException or IOException)
        {
            MessageBox.Show(exception.Message, "自动启动设置失败", MessageBoxButtons.OK, MessageBoxIcon.Error);
            changingStartup = true;
            try
            {
                startAtLogin.Checked = StartupRegistration.IsEnabled;
            }
            finally
            {
                changingStartup = false;
            }
        }
    }

    private static TableLayoutPanel CreateCard()
    {
        var card = new TableLayoutPanel
        {
            AutoSize = true,
            AutoSizeMode = AutoSizeMode.GrowAndShrink,
            Dock = DockStyle.Top,
            ColumnCount = 1,
            Padding = new Padding(20, 17, 20, 17),
            Margin = new Padding(0, 0, 0, 14),
            BackColor = Color.White,
        };
        card.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100));
        return card;
    }

    private static Label CreateSectionTitle(string text) => new()
    {
        Text = text,
        AutoSize = true,
        Font = new Font("Microsoft YaHei UI", 11, FontStyle.Bold),
        ForeColor = Color.FromArgb(30, 41, 59),
        Margin = new Padding(0, 0, 0, 8),
    };

    private static Label CreateBodyLabel() => new()
    {
        AutoSize = true,
        Dock = DockStyle.Fill,
        ForeColor = Color.FromArgb(71, 85, 105),
        MaximumSize = new Size(340, 0),
        Margin = new Padding(0, 2, 0, 5),
    };

    private static Label CreateHint(string text) => new()
    {
        Text = text,
        AutoSize = true,
        Dock = DockStyle.Fill,
        ForeColor = Color.FromArgb(100, 116, 139),
        Margin = new Padding(0, 2, 0, 4),
    };

    private static Panel CreateCapabilityBadge(string title, string protocol)
    {
        var badge = new Panel
        {
            AutoSize = false,
            Height = 54,
            Dock = DockStyle.Top,
            BackColor = Color.FromArgb(239, 246, 255),
            Margin = new Padding(0, 2, 0, 8),
            Padding = new Padding(12, 7, 12, 7),
        };
        badge.Controls.Add(new Label
        {
            Text = $"{title}\n协议：{protocol}",
            AutoSize = true,
            Font = new Font("Microsoft YaHei UI", 9, FontStyle.Bold),
            ForeColor = Color.FromArgb(29, 78, 216),
        });
        return badge;
    }

    private static TextBox CreateTextBox(string text = "", bool usePassword = false) => new()
    {
        Text = text,
        UseSystemPasswordChar = usePassword,
        AutoSize = false,
        Height = 34,
        BorderStyle = BorderStyle.FixedSingle,
        Font = new Font("Segoe UI", 10),
    };

    private static Button CreateButton(string text, int width, bool primary = false)
    {
        var button = new Button
        {
            Text = text,
            AutoSize = false,
            Size = new Size(width, 36),
            FlatStyle = FlatStyle.Flat,
            BackColor = primary ? Color.FromArgb(37, 99, 235) : Color.White,
            ForeColor = primary ? Color.White : Color.FromArgb(51, 65, 85),
            Margin = new Padding(0, 0, 10, 0),
        };
        button.FlatAppearance.BorderColor = primary
            ? Color.FromArgb(37, 99, 235)
            : Color.FromArgb(203, 213, 225);
        return button;
    }

    private static FlowLayoutPanel CreateActions() => new()
    {
        AutoSize = true,
        FlowDirection = FlowDirection.LeftToRight,
        WrapContents = false,
        Dock = DockStyle.Fill,
        Margin = new Padding(0, 10, 0, 0),
    };

    private static void AddField(
        TableLayoutPanel layout, string label, Control control, string hint)
    {
        layout.Controls.Add(new Label
        {
            Text = label,
            AutoSize = true,
            Font = new Font("Microsoft YaHei UI", 9, FontStyle.Bold),
            ForeColor = Color.FromArgb(51, 65, 85),
            Margin = new Padding(0, 8, 0, 4),
        });
        control.Dock = DockStyle.Top;
        control.Margin = new Padding(0, 0, 0, 2);
        layout.Controls.Add(control);
        layout.Controls.Add(CreateHint(hint));
    }
}