using System.Text.Json;
using Kochstube.Models;

namespace Kochstube.Services;

public class RezeptService
{
    private readonly string _rezeptPath;
    private List<Rezept>? _cache;
    private DateTime _lastLoad;

    public RezeptService(IConfiguration config)
    {
        _rezeptPath = config["RezeptPath"] ?? Path.Combine(Directory.GetCurrentDirectory(), "..", "..", "rezepte");
    }

    public List<Rezept> GetAll()
    {
        // Reload if older than 10 seconds (good enough for dev)
        if (_cache == null || DateTime.UtcNow - _lastLoad > TimeSpan.FromSeconds(10))
        {
            _cache = LoadFromDisk();
            _lastLoad = DateTime.UtcNow;
        }
        return _cache;
    }

    public Rezept? GetById(string id) => GetAll().FirstOrDefault(r => r.Id == id);

    public List<string> GetAllTags() => GetAll().SelectMany(r => r.Tags).Distinct().OrderBy(t => t).ToList();

    public List<string> GetAllKategorien() => GetAll().Select(r => r.Kategorie).Distinct().OrderBy(k => k).ToList();

    public List<Rezept> Search(string? query, string? tag, string? kategorie)
    {
        var results = GetAll().AsEnumerable();

        if (!string.IsNullOrWhiteSpace(query))
        {
            var q = query.ToLowerInvariant();
            results = results.Where(r =>
                r.Titel.Contains(q, StringComparison.OrdinalIgnoreCase) ||
                r.Beschreibung.Contains(q, StringComparison.OrdinalIgnoreCase) ||
                r.Zutaten.Any(z => z.Name.Contains(q, StringComparison.OrdinalIgnoreCase)));
        }

        if (!string.IsNullOrWhiteSpace(tag))
            results = results.Where(r => r.Tags.Contains(tag, StringComparer.OrdinalIgnoreCase));

        if (!string.IsNullOrWhiteSpace(kategorie))
            results = results.Where(r => r.Kategorie.Equals(kategorie, StringComparison.OrdinalIgnoreCase));

        return results.ToList();
    }

    private List<Rezept> LoadFromDisk()
    {
        var dir = Path.GetFullPath(_rezeptPath);
        if (!Directory.Exists(dir)) return [];

        var rezepte = new List<Rezept>();
        foreach (var file in Directory.GetFiles(dir, "*.json"))
        {
            try
            {
                var json = File.ReadAllText(file);
                var r = JsonSerializer.Deserialize<Rezept>(json);
                if (r != null) rezepte.Add(r);
            }
            catch { /* skip broken files */ }
        }
        return rezepte.OrderByDescending(r => r.Erstellt ?? "").ThenBy(r => r.Titel).ToList();
    }
}