using System;
using System.IO;
using System.Linq;
using Microsoft.Extensions.Configuration;

namespace Sozsoft.Platform.Data.Seeds;

/// <summary>
/// Runtime'da duzenlenebilen seed dosyalarinin klasorunu cozer.
/// <para>
/// Kod ile birlikte versiyonlanan sabit seed'ler (DbMigrator projesindeki *Data.json dosyalari)
/// buraya dahil degildir; onlar kendi projelerinin ciktisinda kalir.
/// </para>
/// <para>
/// Klasor bilincli olarak hicbir projenin icinde degildir: depoda <c>configs/seeds</c> altinda durur ve
/// konteynere bind mount ile baglanir. Boylece bir seed dosyasi degistiginde ne api ne de migrator
/// imaji yeniden derlenir; deploy sirasindaki <c>git pull</c> yeterlidir. Ayni klasor File Manager
/// uzerinden de duzenlenebildigi icin yapilan degisiklik dogrudan host diskinde kalici olur.
/// </para>
/// <para>
/// Klasor duzeni CDN ile ayni kapsam mantigini izler — once kapsam, sonra icerik turu:
/// <code>
/// seeds/
///   host/                      → host (varsayilan) veritabani kapsami
///     crud/
///     wizard/
///     data/
///     sql/                     → SQL Server saglayicisi
///       object/                → nesne olusturulur/guncellenir
///       execute/               → nesne olusturulur, ayrica tum migration'lar bitince calistirilir
///     postgres/                → PostgreSQL saglayicisi
///       object/
///       execute/
///   tenants/
///     {tenantId}/              → her tenant kendi klasorunde
///       crud/ wizard/ data/ sql/{object,execute}/ postgres/{object,execute}/
/// </code>
/// </para>
/// <para>
/// Cozum sirasi:
/// 1) <c>App:SeedsPath</c> ayari (konteynerde mount noktasi),
/// 2) calisma dizininden yukari dogru <c>configs/seeds</c> aramasi (local gelistirme),
/// 3) calisma dizininin altindaki <c>Seeds</c> klasoru (son care).
/// </para>
/// </summary>
public static class SeedPathResolver
{
    public const string ConfigurationKey = "App:SeedsPath";

    /// <summary>Host veritabani kapsamindaki seed'lerin kok klasoru.</summary>
    public const string HostFolder = "host";

    /// <summary>Tenant kapsamindaki seed'lerin kok klasoru; altinda tenant Id'si ile klasorler bulunur.</summary>
    public const string TenantsFolder = "tenants";

    /// <summary>SQL Server saglayicisinin script klasoru.</summary>
    public const string SqlFolder = "sql";

    /// <summary>PostgreSQL saglayicisinin script klasoru.</summary>
    public const string PostgresFolder = "postgres";

    /// <summary>Yalnizca olusturulan/guncellenen nesne scriptleri.</summary>
    public const string ObjectFolder = "object";

    /// <summary>Olusturulan, ayrica tum migration'lar bittikten sonra calistirilan scriptler.</summary>
    public const string ExecuteFolder = "execute";

    /// <summary>Wizard'in urettigi konfigurasyon dosyalari.</summary>
    public const string WizardFolder = "wizard";

    /// <summary>Crud endpoint konfigurasyon dosyalari.</summary>
    public const string CrudFolder = "crud";

    /// <summary>Liste verisinin aynalandigi seed dosyalari (<c>data/{ListFormCode}.json</c>).</summary>
    public const string DataFolder = "data";

    /// <summary>Bir ListForm icin varsayilan veri seed dosyasinin kapsam klasorune gore goreli yolu.</summary>
    public static string GetDataFilePath(string listFormCode)
    {
        return $"{DataFolder}/{listFormCode}.json";
    }

    private const string RepositorySeedsFolder = "seeds";
    private const string RepositoryConfigsFolder = "configs";
    private const string FallbackFolderName = "Seeds";

    /// <summary>Seed kok klasorunun tam yolunu dondurur. Klasorun var olmasi garanti edilmez.</summary>
    public static string GetRootPath(IConfiguration? configuration)
    {
        var configuredPath = configuration?[ConfigurationKey];
        if (!string.IsNullOrWhiteSpace(configuredPath))
        {
            return Path.GetFullPath(configuredPath);
        }

        var repositoryPath = FindRepositorySeedsPath();
        if (repositoryPath != null)
        {
            return repositoryPath;
        }

        return Path.Combine(Directory.GetCurrentDirectory(), FallbackFolderName);
    }

    /// <summary>Seed kok klasorunun altindaki bir alt yolu dondurur.</summary>
    public static string GetPath(IConfiguration? configuration, params string[] subPaths)
    {
        var path = GetRootPath(configuration);

        foreach (var subPath in subPaths)
        {
            path = Path.Combine(path, subPath);
        }

        return path;
    }

    /// <summary>
    /// Kapsam klasorunun (host ya da ilgili tenant) altindaki yolu dondurur.
    /// <paramref name="tenantId"/> null ise <c>host/</c>, aksi halde <c>tenants/{tenantId}/</c> kullanilir.
    /// </summary>
    public static string GetScopePath(IConfiguration? configuration, Guid? tenantId, params string[] subPaths)
    {
        return GetPath(configuration, BuildScopeSubPaths(tenantId, subPaths));
    }

    /// <summary>Kapsam klasorunun seed koküne gore goreli adi (<c>host</c> ya da <c>tenants/{tenantId}</c>).</summary>
    public static string GetScopeFolderName(Guid? tenantId)
    {
        return tenantId == null
            ? HostFolder
            : $"{TenantsFolder}/{tenantId.Value}";
    }

    /// <summary>Aktif veritabani saglayicisina karsilik gelen script klasorunun adi.</summary>
    public static string GetProviderFolderName(bool isPostgreSql)
    {
        return isPostgreSql ? PostgresFolder : SqlFolder;
    }

    private static string[] BuildScopeSubPaths(Guid? tenantId, string[] subPaths)
    {
        var scopeSegments = tenantId == null
            ? new[] { HostFolder }
            : new[] { TenantsFolder, tenantId.Value.ToString() };

        return scopeSegments.Concat(subPaths ?? Array.Empty<string>()).ToArray();
    }

    /// <summary>Calisma dizininden yukari dogru cikarak depodaki configs/seeds klasorunu arar.</summary>
    private static string? FindRepositorySeedsPath()
    {
        var dir = new DirectoryInfo(Directory.GetCurrentDirectory());

        while (dir != null)
        {
            var candidate = Path.Combine(dir.FullName, RepositoryConfigsFolder, RepositorySeedsFolder);
            if (Directory.Exists(candidate))
            {
                return candidate;
            }

            dir = dir.Parent;
        }

        return null;
    }
}