// Copyright © 2010 Xamasoft

using Newtonsoft.Json;
using System.Globalization;
using System.Text;

namespace Json2CSharpCodeGenerator.Lib;

public class FieldInfo
{
    public FieldInfo(
        IJsonClassGeneratorConfig generator,
        string jsonMemberName,
        JsonType type,
        bool usePascalCase,
        IReadOnlyList<object> examples
    )
    {
        this._Generator = generator ?? throw new ArgumentNullException(nameof(generator));
        JsonMemberName = jsonMemberName ?? throw new ArgumentNullException(nameof(jsonMemberName));
        MemberName = jsonMemberName;
        ContainsSpecialChars = IsContainsSpecialChars(MemberName);

        if (usePascalCase || ContainsSpecialChars)
        {
            MemberName = JsonClassGenerator.ToTitleCase(MemberName);
        }

        Type = type ?? throw new ArgumentNullException(nameof(type));
        Examples = examples ?? Array.Empty<object>();
    }

    private readonly IJsonClassGeneratorConfig _Generator;

    /// <summary>Pascal-cased.</summary>
    public string MemberName { get; }
    /// <summary>Normally camelCased.</summary>
    public string JsonMemberName { get; }
    public JsonType Type { get; }
    public IReadOnlyList<object> Examples { get; }

    public bool ContainsSpecialChars { get; set; }
    public int MyProperty { get; set; }

    private static bool IsContainsSpecialChars(string text)
    {
        for (int i = 0; i < text.Length; i++)
        {
            char c = text[i];
            if (!char.IsLetterOrDigit(c) && c != '_')
            {
                return true;
            }
        }

        return false;
    }

    internal static string ToTitleCase(string text)
    {
        if (text is null)
            throw new ArgumentNullException(nameof(text));
        if (string.IsNullOrWhiteSpace(text))
            return text;

        StringBuilder sb = new(text.Length);
        bool lastCharWasSpecial = true;

        for (int i = 0; i < text.Length; i++)
        {
            char c = text[i];
            if (char.IsLetterOrDigit(c))
            {
                _ = sb.Append(lastCharWasSpecial ? char.ToUpper(c) : c);
                lastCharWasSpecial = false;
            }
            else
            {
                lastCharWasSpecial = true;
            }
        }

        return sb.ToString();
    }

    public string GetGenerationCode(string jObject)
    {
        if (jObject is null)
            throw new ArgumentNullException(nameof(jObject));

        if (Type.Type == JsonTypeEnum.Array)
        {
            JsonType innermost = Type.GetInnermostType();
            return string.Format(CultureInfo.InvariantCulture, "({1})JsonClassHelper.ReadArray<{5}>(JsonClassHelper.GetJToken<JArray>({0}, \"{2}\"), JsonClassHelper.{3}, typeof({6}))",
                jObject,
                Type.GetTypeName(),
                JsonMemberName,
                innermost.GetReaderName(),
                -1,
                innermost.GetTypeName(),
                Type.GetTypeName()
            );
        }
        else if (Type.Type == JsonTypeEnum.Dictionary)
        {
            return string.Format(CultureInfo.InvariantCulture, "({1})JsonClassHelper.ReadDictionary<{2}>(JsonClassHelper.GetJToken<JObject>({0}, \"{3}\"))",
                jObject,
                Type.GetTypeName(),
                Type.InternalType.GetTypeName(),
                JsonMemberName,
                Type.GetTypeName()
            );
        }
        else
        {
            return string.Format(CultureInfo.InvariantCulture, "JsonClassHelper.{1}(JsonClassHelper.GetJToken<{2}>({0}, \"{3}\"))",
                jObject,
                Type.GetReaderName(),
                Type.GetJTokenType(),
                JsonMemberName
            );
        }

    }

    public string GetExamplesText() => string.Join(separator: ", ", values: Examples.Take(5).Select(x => JsonConvert.SerializeObject(x)));

}