// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System;
using System.Diagnostics.CodeAnalysis;
using System.IO;
using Microsoft.AspNetCore.Http.Features;
using Microsoft.AspNetCore.Rewrite.IISUrlRewrite;
using Microsoft.Extensions.FileProviders;

namespace Microsoft.AspNetCore.Rewrite
{
    /// <summary>
    /// Extensions for adding IIS Url Rewrite rules to <see cref="RewriteOptions"/>
    /// </summary>
    public static class IISUrlRewriteOptionsExtensions
    {
        /// <summary>
        /// Add rules from a IIS config file containing Url Rewrite rules
        /// </summary>
        /// <param name="options">The <see cref="RewriteOptions"/></param>
        /// <param name="fileProvider">The <see cref="IFileProvider"/> </param>
        /// <param name="filePath">The path to the file containing UrlRewrite rules.</param>
        /// <param name="alwaysUseManagedServerVariables">Server variables are by default sourced from the server if it supports the <see cref="IServerVariablesFeature"/> feature. Use <c>true</c> to disable that behavior</param>
        [SuppressMessage("ApiDesign", "RS0026:Do not add multiple public overloads with optional parameters", Justification = "Required for backwards compatability")]
        public static RewriteOptions AddIISUrlRewrite(this RewriteOptions options, IFileProvider fileProvider, string filePath, bool alwaysUseManagedServerVariables = false)
        {
            if (options == null)
            {
                throw new ArgumentNullException(nameof(options));
            }

            if (fileProvider == null)
            {
                throw new ArgumentNullException(nameof(fileProvider));
            }

            var file = fileProvider.GetFileInfo(filePath);

            using (var stream = file.CreateReadStream())
            {
                return AddIISUrlRewrite(options, new StreamReader(stream), alwaysUseManagedServerVariables);
            }
        }

        /// <summary>
        /// Add rules from a IIS config file containing Url Rewrite rules
        /// </summary>
        /// <param name="options">The <see cref="RewriteOptions"/></param>
        /// <param name="reader">The text reader stream.</param>
        /// <param name="alwaysUseManagedServerVariables">Server variables are by default sourced from the server if it supports the <see cref="IServerVariablesFeature"/> feature. Use <c>true</c> to disable that behavior</param>
        [SuppressMessage("ApiDesign", "RS0026:Do not add multiple public overloads with optional parameters", Justification = "<Pending>")]
        public static RewriteOptions AddIISUrlRewrite(this RewriteOptions options, TextReader reader, bool alwaysUseManagedServerVariables = false)
        {
            if (options == null)
            {
                throw new ArgumentNullException(nameof(options));
            }

            if (reader == null)
            {
                throw new ArgumentNullException(nameof(reader));
            }

            var rules = new UrlRewriteFileParser().Parse(reader, alwaysUseManagedServerVariables);

            foreach (var rule in rules)
            {
                options.Rules.Add(rule);
            }

            return options;
        }
    }
}
