// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.

using System.Text.Json;
using System.Text.Json.Serialization;

using Microsoft.Teams.Common;

namespace Microsoft.Teams.Api.Activities.Invokes;

public partial class Name : StringEnum
{
    public bool IsSignIn => Value.StartsWith("signin/");
}

/// <summary>
/// Any SignIn Activity
/// </summary>
[JsonConverter(typeof(JsonConverter))]
public abstract class SignInActivity(Name.SignIn name) : InvokeActivity(new(name.Value))
{
    public SignIn.TokenExchangeActivity ToTokenExchange() => (SignIn.TokenExchangeActivity)this;
    public SignIn.VerifyStateActivity ToVerifyState() => (SignIn.VerifyStateActivity)this;

    public override object ToType(Type type, IFormatProvider? provider)
    {
        if (type == typeof(SignIn.TokenExchangeActivity)) return ToTokenExchange();
        if (type == typeof(SignIn.VerifyStateActivity)) return ToVerifyState();
        return this;
    }

    public new class JsonConverter : JsonConverter<SignInActivity>
    {
        public override bool CanConvert(Type typeToConvert)
        {
            return base.CanConvert(typeToConvert);
        }

        public override SignInActivity? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
        {
            var element = JsonSerializer.Deserialize<JsonElement>(ref reader, options);

            if (!element.TryGetProperty("name", out JsonElement property))
            {
                throw new JsonException("invoke activity must have a 'name' property");
            }

            var name = property.Deserialize<string>(options);

            if (name is null)
            {
                throw new JsonException("failed to deserialize invoke activity 'name' property");
            }

            return name switch
            {
                "signin/tokenExchange" => JsonSerializer.Deserialize<SignIn.TokenExchangeActivity>(element.ToString(), options),
                "signin/verifyState" => JsonSerializer.Deserialize<SignIn.VerifyStateActivity>(element.ToString(), options),
                _ => throw new JsonException($"failed to deserialize signin activity '{name}' doesn't match any known types.")
            };
        }

        public override void Write(Utf8JsonWriter writer, SignInActivity value, JsonSerializerOptions options)
        {
            if (value is SignIn.TokenExchangeActivity tokenExchange)
            {
                JsonSerializer.Serialize(writer, tokenExchange, options);
                return;
            }

            if (value is SignIn.VerifyStateActivity verifyState)
            {
                JsonSerializer.Serialize(writer, verifyState, options);
                return;
            }

            JsonSerializer.Serialize(writer, value, options);
        }
    }
}