using System.Text.Json;
using System.Text.Json.Serialization;
using ClaudeDo.Data;

namespace ClaudeDo.Ui;

public sealed class AppSettings
{
    public string DbPath { get; set; } = "~/.claudeDo/todo.db";
    public string SignalRUrl { get; set; } = "http://127.0.0.1:47821/hub";
    public string Language { get; set; } = "";
    public string AccentPreset { get; set; } = "";

    /// Diff viewer layout: "unified" or "split". A view preference, so it lives here in
    /// ui.config.json rather than in the worker-owned AppSettingsEntity.
    public string DiffViewMode { get; set; } = "unified";
    public bool DiffWrapLines { get; set; }

    /// <summary>Mission Control overview column count; 0 = auto (derived from the pane count).</summary>
    public int MissionControlColumns { get; set; }

    private static readonly string DefaultConfigPath = Paths.Expand("~/.claudeDo/ui.config.json");

    /// Where this instance persists. Instance-level (not static) so tests can redirect it —
    /// the diff-viewer toggles call Save() on every flip.
    [JsonIgnore]
    public string ConfigPath { get; set; } = DefaultConfigPath;

    public static AppSettings Load(string? configPath = null)
    {
        var path = configPath ?? DefaultConfigPath;
        try
        {
            if (File.Exists(path))
            {
                var json = File.ReadAllText(path);
                var loaded = JsonSerializer.Deserialize<AppSettings>(json,
                    new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
                if (loaded is not null)
                {
                    loaded.ConfigPath = path;
                    return loaded;
                }
            }
        }
        catch
        {
            // Fall through to defaults
        }
        return new AppSettings { ConfigPath = path };
    }

    public void Save()
    {
        var dir = Path.GetDirectoryName(ConfigPath);
        if (!string.IsNullOrEmpty(dir)) Directory.CreateDirectory(dir);
        var json = JsonSerializer.Serialize(this, new JsonSerializerOptions { WriteIndented = true });
        File.WriteAllText(ConfigPath, json);
    }
}