using System.Text.Json;

using System.Text.Json.Nodes;

namespace NpgsqlRestClient;

public static class Config

{

public static IConfigurationRoot Cfg { get; private set; } = null!;

public static IConfigurationSection NpgsqlRestCfg { get; private set; } = null!;

public static IConfigurationSection AuthCfg { get; private set; } = null!;

public static string CurrentDir => Directory.GetCurrentDirectory();

public static void Build(string[] args)

{

IConfigurationBuilder configBuilder;

var tempBuilder = new ConfigurationBuilder();

IConfigurationRoot tempCfg;

if (args.Length > 0)

{

foreach (var (fileName, optional) in Arguments.EnumerateConfigFiles(args))

{

tempBuilder.AddJsonFile(Path.GetFullPath(fileName, CurrentDir), optional: optional);

}

tempCfg = tempBuilder.Build();

}

else

{

tempCfg = tempBuilder

.AddJsonFile("appsettings.json", optional: false)

.AddJsonFile("appsettings.Development.json", optional: true)

.Build();

}

var cfgCfg = tempCfg.GetSection("Config");

if (cfgCfg != null && GetConfigBool("AddEnvironmentVariables", cfgCfg))

{

configBuilder = new ConfigurationBuilder().AddEnvironmentVariables();

}

else

{

configBuilder = new ConfigurationBuilder();

}

if (args.Length > 0)

{

foreach (var (fileName, optional) in Arguments.EnumerateConfigFiles(args))

{

configBuilder.AddJsonFile(Path.GetFullPath(fileName, CurrentDir), optional: optional);

}

Cfg = configBuilder.Build();

}

else

{

Cfg = configBuilder

.AddJsonFile("appsettings.json", optional: false)

.AddJsonFile("appsettings.Development.json", optional: true)

.Build();

}

NpgsqlRestCfg = Cfg.GetSection("NpgsqlRest");

AuthCfg = NpgsqlRestCfg.GetSection("AuthenticationOptions");

}

public static bool Exists(this IConfigurationSection? section)

{

if (section is null)

{

return false;

}

if (section.GetChildren().Any() is false)

{

return false;

}

return true;

}

public static bool GetConfigBool(string key, IConfiguration? subsection = null, bool defaultVal = false)

{

var section = subsection?.GetSection(key) ?? Cfg.GetSection(key);

if (string.IsNullOrEmpty(section?.Value))

{

return defaultVal;

}

return string.Equals(section?.Value, "true", StringComparison.OrdinalIgnoreCase);

}

public static string? GetConfigStr(string key, IConfiguration? subsection = null)

{

var section = subsection?.GetSection(key) ?? Cfg.GetSection(key);

return string.IsNullOrEmpty(section?.Value) ? null : section.Value;

}

public static int? GetConfigInt(string key, IConfiguration? subsection = null)

{

var section = subsection?.GetSection(key) ?? Cfg.GetSection(key);

if (section?.Value is null)

{

return null;

}

if (int.TryParse(section.Value, out var value))

{

return value;

}

return null;

}

public static T? GetConfigEnum<T>(string key, IConfiguration? subsection = null)

{

var section = subsection?.GetSection(key) ?? Cfg.GetSection(key);

if (string.IsNullOrEmpty(section?.Value))

{

return default;

}

return GetEnum<T>(section?.Value);

}

public static T? GetEnum<T>(string? value)

{

if (value is null)

{

return default;

}

var type = typeof(T);

var nullable = Nullable.GetUnderlyingType(type);

var names = Enum.GetNames(nullable ?? type);

foreach (var name in names)

{

if (string.Equals(value, name, StringComparison.OrdinalIgnoreCase))

{

return (T)Enum.Parse(nullable ?? type, name);

}

}

return default;

}

public static IEnumerable<string>? GetConfigEnumerable(string key, IConfiguration? subsection = null)

{

var section = subsection is not null ? subsection?.GetSection(key) : Cfg.GetSection(key);

var children = section?.GetChildren().ToArray();

if (children is null || (children.Length == 0 && section?.Value == ""))

{

return null;

}

return children.Select(c => c.Value ?? "");

}

public static T? GetConfigFlag<T>(string key, IConfiguration? subsection = null)

{

var array = GetConfigEnumerable(key, subsection)?.ToArray();

if (array is null)

{

return default;

}

var type = typeof(T);

var nullable = Nullable.GetUnderlyingType(type);

var names = Enum.GetNames(nullable ?? type);

T? result = default;

foreach (var value in array)

{

foreach (var name in names)

{

if (string.Equals(value, name, StringComparison.OrdinalIgnoreCase))

{

var e = (T)Enum.Parse(nullable ?? type, name);

if (result is null)

{

result = e;

}

else

{

result = (T)Enum.ToObject(type, Convert.ToInt32(result) | Convert.ToInt32(e));

}

}

}

}

return result;

}

public static string Serialize()

{

var json = SerializeConfig(Cfg);

return json?.ToJsonString(new JsonSerializerOptions() { WriteIndented = true }) ?? "{}";

}

private static JsonNode? SerializeConfig(IConfiguration config)

{

JsonObject obj = new();

foreach (var child in config.GetChildren())

{

if (child.Path.EndsWith(":0"))

{

var arr = new JsonArray();

foreach (var arrayChild in config.GetChildren())

{

arr.Add(SerializeConfig(arrayChild));

}

return arr;

}

else

{

obj.Add(child.Key, SerializeConfig(child));

}

}

if (obj.Count() == 0 && config is IConfigurationSection section)

{

if (bool.TryParse(section.Value, out bool boolean))

{

return JsonValue.Create(boolean);

}

else if (decimal.TryParse(section.Value, out decimal real))

{

return JsonValue.Create(real);

}

else if (long.TryParse(section.Value, out long integer))

{

return JsonValue.Create(integer);

}

if (section.Path.StartsWith("ConnectionStrings:"))

{

return JsonValue.Create(string.Join(';',

section?.Value?.Split(';')?.Where(p => p.StartsWith("password", StringComparison.OrdinalIgnoreCase) is false) ?? []));

}

return JsonValue.Create(section.Value);

}

return obj;

}

}