using System;
using System.Reactive.Threading.Tasks;
using Octokit.Reactive.Internal;

namespace Octokit.Reactive
{
    /// <summary>
    /// Client for accessing contents of files within a repository as base64 encoded content.
    /// </summary>
    public class ObservableRepositoryContentsClient : IObservableRepositoryContentsClient
    {
        readonly IGitHubClient _client;

        /// <summary>
        /// Creates an instance of <see cref="ObservableRepositoryContentsClient"/>.
        /// </summary>
        /// <param name="client"></param>
        public ObservableRepositoryContentsClient(IGitHubClient client)
        {
            _client = client;
        }

        /// <summary>
        /// Returns the HTML rendered README.
        /// </summary>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <returns></returns>
        public IObservable<Readme> GetReadme(string owner, string name)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            return _client.Repository.Content.GetReadme(owner, name).ToObservable();
        }

        /// <summary>
        /// Returns just the HTML portion of the README without the surrounding HTML document. 
        /// </summary>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <returns></returns>
        public IObservable<string> GetReadmeHtml(string owner, string name)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            return _client.Repository.Content.GetReadmeHtml(owner, name).ToObservable();
        }


        /// <summary>
        /// This method will return a 302 to a URL to download a tarball or zipball archive for a repository.
        /// Please make sure your HTTP framework is configured to follow redirects or you will need to use the 
        /// Location header to make a second GET request.
        /// Note: For private repositories, these links are temporary and expire quickly.
        /// </summary>
        /// <remarks>https://developer.github.com/v3/repos/contents/#get-archive-link</remarks>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <returns></returns>
        public IObservable<string> GetArchiveLink(string owner, string name)
        {
            return GetArchiveLink(owner, name, ArchiveFormat.Tarball, string.Empty);
        }

        /// <summary>
        /// This method will return a 302 to a URL to download a tarball or zipball archive for a repository.
        /// Please make sure your HTTP framework is configured to follow redirects or you will need to use the 
        /// Location header to make a second GET request.
        /// Note: For private repositories, these links are temporary and expire quickly.
        /// </summary>
        /// <remarks>https://developer.github.com/v3/repos/contents/#get-archive-link</remarks>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <param name="archiveFormat">The format of the archive. Can be either tarball or zipball</param>
        /// <returns></returns>
        public IObservable<string> GetArchiveLink(string owner, string name, ArchiveFormat archiveFormat)
        {
            return GetArchiveLink(owner, name, archiveFormat, String.Empty);
        }

        /// <summary>
        /// This method will return a 302 to a URL to download a tarball or zipball archive for a repository.
        /// Please make sure your HTTP framework is configured to follow redirects or you will need to use the 
        /// Location header to make a second GET request.
        /// Note: For private repositories, these links are temporary and expire quickly.
        /// </summary>
        /// <remarks>https://developer.github.com/v3/repos/contents/#get-archive-link</remarks>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <param name="archiveFormat">The format of the archive. Can be either tarball or zipball</param>
        /// <param name="reference">A valid Git reference.</param>
        /// <returns></returns>
        public IObservable<string> GetArchiveLink(string owner, string name, ArchiveFormat archiveFormat, string reference)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            return _client.Repository.Content.GetArchiveLink(owner, name, archiveFormat, reference).ToObservable();
        }

        /// <summary>
        /// Returns the contents of a file or directory in a repository.
        /// </summary>
        /// <remarks>
        /// If given a path to a single file, this method returns a collection containing only that file.
        /// </remarks>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <param name="path">The content path</param>
        /// <returns>
        /// A collection of <see cref="RepositoryContent"/> representing the content at the specified path
        /// </returns>
        public IObservable<RepositoryContent> GetAllContents(string owner, string name, string path)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");
            Ensure.ArgumentNotNullOrEmptyString(path, "path");

            return _client
                .Connection
                .GetAndFlattenAllPages<RepositoryContent>(ApiUrls.RepositoryContent(owner, name, path));
        }

        /// <summary>
        /// Creates a commit that creates a new file in a repository.
        /// </summary>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <param name="path">The path to the file</param>
        /// <param name="request">Information about the file to create</param>
        /// <returns></returns>
        public IObservable<RepositoryContentChangeSet> CreateFile(string owner, string name, string path, CreateFileRequest request)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");
            Ensure.ArgumentNotNullOrEmptyString(path, "path");
            Ensure.ArgumentNotNull(request, "request");

            return _client.Repository.Content.CreateFile(owner, name, path, request).ToObservable();
        }

        /// <summary>
        /// Creates a commit that updates the contents of a file in a repository.
        /// </summary>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <param name="path">The path to the file</param>
        /// <param name="request">Information about the file to update</param>
        /// <returns>The updated content</returns>
        public IObservable<RepositoryContentChangeSet> UpdateFile(string owner, string name, string path, UpdateFileRequest request)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");
            Ensure.ArgumentNotNullOrEmptyString(path, "path");
            Ensure.ArgumentNotNull(request, "request");

            return _client.Repository.Content.UpdateFile(owner, name, path, request).ToObservable();
        }

        public IObservable<System.Reactive.Unit> DeleteFile(string owner, string name, string path, DeleteFileRequest request)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");
            Ensure.ArgumentNotNullOrEmptyString(path, "path");
            Ensure.ArgumentNotNull(request, "request");

            return _client.Repository.Content.DeleteFile(owner, name, path, request).ToObservable();
        }
    }
}