using System.Management;
using System.Runtime.InteropServices;

namespace VisitorSystemInfo;

public sealed class MainForm : Form
{
    private readonly Label _osValue;
    private readonly Label _cpuValue;
    private readonly Label _gpuValue;
    private readonly Label _ramValue;

    public MainForm()
    {
        Text = "Systeminfo";
        StartPosition = FormStartPosition.CenterScreen;
        MinimumSize = new Size(720, 420);
        BackColor = Color.FromArgb(8, 20, 26);
        ForeColor = Color.FromArgb(241, 255, 253);
        Font = new Font("Segoe UI", 10F, FontStyle.Regular, GraphicsUnit.Point);

        var title = new Label
        {
            AutoSize = true,
            Font = new Font("Segoe UI Semibold", 22F, FontStyle.Bold, GraphicsUnit.Point),
            Text = "Systeminfo",
            ForeColor = Color.FromArgb(118, 225, 214),
            Margin = new Padding(0, 0, 0, 8),
        };

        var subtitle = new Label
        {
            AutoSize = true,
            MaximumSize = new Size(640, 0),
            Text = "Visar datorns operativsystem, CPU, GPU och RAM direkt i Windows.",
            ForeColor = Color.FromArgb(155, 201, 196),
            Margin = new Padding(0, 0, 0, 18),
        };

        var layout = new TableLayoutPanel
        {
            Dock = DockStyle.Fill,
            ColumnCount = 1,
            RowCount = 6,
            Padding = new Padding(24),
            BackColor = Color.FromArgb(8, 20, 26),
        };

        layout.Controls.Add(title);
        layout.Controls.Add(subtitle);

        _osValue = AddInfoCard(layout, "OS");
        _cpuValue = AddInfoCard(layout, "CPU");
        _gpuValue = AddInfoCard(layout, "GPU");
        _ramValue = AddInfoCard(layout, "RAM");

        Controls.Add(layout);
        Load += (_, _) => PopulateInfo();
    }

    private static Label AddInfoCard(TableLayoutPanel layout, string labelText)
    {
        var card = new Panel
        {
            Height = 68,
            Width = 640,
            Margin = new Padding(0, 0, 0, 12),
            Padding = new Padding(16, 12, 16, 12),
            BackColor = Color.FromArgb(15, 38, 49),
        };

        var label = new Label
        {
            AutoSize = true,
            Text = labelText,
            Font = new Font("Segoe UI", 9F, FontStyle.Bold, GraphicsUnit.Point),
            ForeColor = Color.FromArgb(255, 209, 102),
            Dock = DockStyle.Top,
        };

        var value = new Label
        {
            AutoEllipsis = true,
            Dock = DockStyle.Bottom,
            Height = 26,
            Text = "Läser in...",
            ForeColor = Color.FromArgb(241, 255, 253),
        };

        card.Controls.Add(value);
        card.Controls.Add(label);
        layout.Controls.Add(card);
        return value;
    }

    private void PopulateInfo()
    {
        _osValue.Text = GetOsName();
        _cpuValue.Text = QueryFirst("Win32_Processor", "Name");
        _gpuValue.Text = QueryJoined("Win32_VideoController", "Name");
        _ramValue.Text = GetRamText();
    }

    private static string GetOsName()
    {
        var caption = QueryFirst("Win32_OperatingSystem", "Caption");
        var version = QueryFirst("Win32_OperatingSystem", "Version");

        if (!string.IsNullOrWhiteSpace(caption) && !string.IsNullOrWhiteSpace(version))
        {
            return $"{caption} ({version})";
        }

        return RuntimeInformation.OSDescription;
    }

    private static string GetRamText()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT TotalPhysicalMemory FROM Win32_ComputerSystem");
            foreach (ManagementObject obj in searcher.Get())
            {
                if (obj["TotalPhysicalMemory"] is not null &&
                    ulong.TryParse(obj["TotalPhysicalMemory"].ToString(), out var totalBytes))
                {
                    var gib = totalBytes / 1024d / 1024d / 1024d;
                    return $"{gib:F1} GB";
                }
            }
        }
        catch
        {
        }

        return "Okänt";
    }

    private static string QueryFirst(string className, string propertyName)
    {
        try
        {
            using var searcher = new ManagementObjectSearcher($"SELECT {propertyName} FROM {className}");
            foreach (ManagementObject obj in searcher.Get())
            {
                var value = obj[propertyName]?.ToString();
                if (!string.IsNullOrWhiteSpace(value))
                {
                    return value.Trim();
                }
            }
        }
        catch
        {
        }

        return "Okänt";
    }

    private static string QueryJoined(string className, string propertyName)
    {
        try
        {
            using var searcher = new ManagementObjectSearcher($"SELECT {propertyName} FROM {className}");
            var values = new List<string>();

            foreach (ManagementObject obj in searcher.Get())
            {
                var value = obj[propertyName]?.ToString();
                if (!string.IsNullOrWhiteSpace(value))
                {
                    values.Add(value.Trim());
                }
            }

            if (values.Count > 0)
            {
                return string.Join(", ", values.Distinct(StringComparer.OrdinalIgnoreCase));
            }
        }
        catch
        {
        }

        return "Okänt";
    }
}