using System.Text;

namespace MarketAlly.AIPlugin.ClaudeCode;

/// <summary>
/// HTTP client interface with built-in rate limiting awareness
/// </summary>
public interface IRateLimitAwareHttpClient
{
    /// <summary>
    /// Sends a GET request with rate limit handling
    /// </summary>
    /// <param name="endpoint">API endpoint</param>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>HTTP response with rate limit info</returns>
    Task<RateLimitAwareResponse> GetAsync(string endpoint, CancellationToken cancellationToken = default);

    /// <summary>
    /// Sends a POST request with rate limit handling
    /// </summary>
    /// <param name="endpoint">API endpoint</param>
    /// <param name="content">Request content</param>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>HTTP response with rate limit info</returns>
    Task<RateLimitAwareResponse> PostAsync(string endpoint, HttpContent? content = null, CancellationToken cancellationToken = default);

    /// <summary>
    /// Sends a POST request with JSON content
    /// </summary>
    /// <param name="endpoint">API endpoint</param>
    /// <param name="data">Data to serialize as JSON</param>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>HTTP response with rate limit info</returns>
    Task<RateLimitAwareResponse> PostAsJsonAsync<T>(string endpoint, T data, CancellationToken cancellationToken = default);

    /// <summary>
    /// Sends a PUT request with rate limit handling
    /// </summary>
    /// <param name="endpoint">API endpoint</param>
    /// <param name="content">Request content</param>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>HTTP response with rate limit info</returns>
    Task<RateLimitAwareResponse> PutAsync(string endpoint, HttpContent? content = null, CancellationToken cancellationToken = default);

    /// <summary>
    /// Sends a DELETE request with rate limit handling
    /// </summary>
    /// <param name="endpoint">API endpoint</param>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>HTTP response with rate limit info</returns>
    Task<RateLimitAwareResponse> DeleteAsync(string endpoint, CancellationToken cancellationToken = default);

    /// <summary>
    /// Gets current rate limit status
    /// </summary>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>Current rate limit information</returns>
    Task<RateLimitInfo> GetRateLimitStatusAsync(CancellationToken cancellationToken = default);

    /// <summary>
    /// Checks if a request can be made without hitting rate limits
    /// </summary>
    /// <param name="endpoint">Optional endpoint to check</param>
    /// <returns>True if request can be made</returns>
    Task<bool> CanMakeRequestAsync(string? endpoint = null);

    /// <summary>
    /// Waits for rate limit reset if necessary
    /// </summary>
    /// <param name="maxWaitTime">Maximum time to wait</param>
    /// <param name="cancellationToken">Cancellation token</param>
    /// <returns>True if reset occurred, false if timeout</returns>
    Task<bool> WaitForRateLimitResetAsync(TimeSpan? maxWaitTime = null, CancellationToken cancellationToken = default);

    /// <summary>
    /// Configures the HTTP client with authentication and base settings
    /// </summary>
    /// <param name="baseUrl">Base URL for the API</param>
    /// <param name="apiKey">API key for authentication</param>
    /// <param name="tenantId">Optional tenant ID</param>
    void Configure(string baseUrl, string apiKey, string? tenantId = null);
}

/// <summary>
/// HTTP response with rate limit information
/// </summary>
public class RateLimitAwareResponse
{
    public bool IsSuccessStatusCode { get; set; }
    public int StatusCode { get; set; }
    public string? Content { get; set; }
    public RateLimitInfo? RateLimitInfo { get; set; }
    public Dictionary<string, string> Headers { get; set; } = new();
    public string? ErrorMessage { get; set; }
    public bool IsRateLimited { get; set; }
    public TimeSpan? RetryAfter { get; set; }

    /// <summary>
    /// Deserializes the response content as JSON
    /// </summary>
    /// <typeparam name="T">Type to deserialize to</typeparam>
    /// <returns>Deserialized object</returns>
    public T? DeserializeJson<T>()
    {
        if (string.IsNullOrEmpty(Content))
            return default;

        try
        {
            return System.Text.Json.JsonSerializer.Deserialize<T>(Content, new System.Text.Json.JsonSerializerOptions
            {
                PropertyNameCaseInsensitive = true
            });
        }
        catch
        {
            return default;
        }
    }

    /// <summary>
    /// Ensures the response was successful, throwing an exception if not
    /// </summary>
    /// <returns>This response for chaining</returns>
    /// <exception cref="HttpRequestException">Thrown if the request was not successful</exception>
    public RateLimitAwareResponse EnsureSuccessStatusCode()
    {
        if (!IsSuccessStatusCode)
        {
            var message = !string.IsNullOrEmpty(ErrorMessage) 
                ? ErrorMessage 
                : $"HTTP request failed with status code {StatusCode}";
            
            if (IsRateLimited)
            {
                throw new RateLimitExceededException(message, RateLimitInfo, RetryAfter);
            }
            
            throw new HttpRequestException(message);
        }
        
        return this;
    }

    /// <summary>
    /// Creates a successful response
    /// </summary>
    /// <param name="content">Response content</param>
    /// <param name="rateLimitInfo">Rate limit information</param>
    /// <returns>Successful response</returns>
    public static RateLimitAwareResponse Success(string content, RateLimitInfo? rateLimitInfo = null)
    {
        return new RateLimitAwareResponse
        {
            IsSuccessStatusCode = true,
            StatusCode = 200,
            Content = content,
            RateLimitInfo = rateLimitInfo
        };
    }

    /// <summary>
    /// Creates an error response
    /// </summary>
    /// <param name="statusCode">HTTP status code</param>
    /// <param name="errorMessage">Error message</param>
    /// <param name="rateLimitInfo">Rate limit information</param>
    /// <returns>Error response</returns>
    public static RateLimitAwareResponse Error(int statusCode, string errorMessage, RateLimitInfo? rateLimitInfo = null)
    {
        return new RateLimitAwareResponse
        {
            IsSuccessStatusCode = false,
            StatusCode = statusCode,
            ErrorMessage = errorMessage,
            RateLimitInfo = rateLimitInfo,
            IsRateLimited = statusCode == 429
        };
    }
}

/// <summary>
/// Exception thrown when rate limits are exceeded
/// </summary>
public class RateLimitExceededException : Exception
{
    public RateLimitInfo? RateLimitInfo { get; }
    public TimeSpan? RetryAfter { get; }

    public RateLimitExceededException(string message, RateLimitInfo? rateLimitInfo = null, TimeSpan? retryAfter = null) 
        : base(message)
    {
        RateLimitInfo = rateLimitInfo;
        RetryAfter = retryAfter;
    }

    public RateLimitExceededException(string message, Exception innerException, RateLimitInfo? rateLimitInfo = null, TimeSpan? retryAfter = null) 
        : base(message, innerException)
    {
        RateLimitInfo = rateLimitInfo;
        RetryAfter = retryAfter;
    }
}

/// <summary>
/// HTTP client configuration options
/// </summary>
public class HttpClientOptions
{
    public string BaseUrl { get; set; } = string.Empty;
    public string ApiKey { get; set; } = string.Empty;
    public string? TenantId { get; set; }
    public TimeSpan Timeout { get; set; } = TimeSpan.FromMinutes(5);
    public int MaxRetries { get; set; } = 3;
    public TimeSpan BaseRetryDelay { get; set; } = TimeSpan.FromSeconds(1);
    public double BackoffMultiplier { get; set; } = 2.0;
    public Dictionary<string, string> DefaultHeaders { get; set; } = new();
    public bool EnableDetailedLogging { get; set; } = false;
}