using System;
#if NET_45
using System.Collections.Generic;
#endif
using System.Threading.Tasks;

namespace Octokit
{
    /// <summary>
    /// A client for GitHub's Repositories API.
    /// </summary>
    /// <remarks>
    /// See the <a href="http://developer.github.com/v3/repos/">Repositories API documentation</a> for more details.
    /// </remarks>
    public class RepositoriesClient : ApiClient, IRepositoriesClient
    {
        /// <summary>
        /// Initializes a new GitHub Repos API client.
        /// </summary>
        /// <param name="apiConnection">An API connection.</param>
        public RepositoriesClient(IApiConnection apiConnection) : base(apiConnection)
        {
            CommitStatus = new CommitStatusClient(apiConnection);
            _hooks = new Lazy<IRepositoryHooksClient>(() => new RepositoryHooksClient(apiConnection));
        }

        /// <summary>
        /// Creates a new repository for the current user.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#create">API documentation</a> for more information.
        /// </remarks>
        /// <param name="newRepository">A <see cref="NewRepository"/> instance describing the new repository to create.</param>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns>A <see cref="Repository"/> instance for the created repository.</returns>
        public Task<Repository> Create(NewRepository newRepository)
        {
            Ensure.ArgumentNotNull(newRepository, "newRepository");
            if (string.IsNullOrEmpty(newRepository.Name))
                throw new ArgumentException("The new repository's name must not be null.");

            return ApiConnection.Post<Repository>(ApiUrls.Repositories(), newRepository);
        }

        /// <summary>
        /// Creates a new repository in the specified organization.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#create">API documentation</a> for more information.
        /// </remarks>
        /// <param name="organizationLogin">Login of the organization in which to create the repostiory.</param>
        /// <param name="newRepository">A <see cref="NewRepository"/> instance describing the new repository to create.</param>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns>A <see cref="Repository"/> instance for the created repository</returns>
        public Task<Repository> Create(string organizationLogin, NewRepository newRepository)
        {
            Ensure.ArgumentNotNull(organizationLogin, "organizationLogin");
            Ensure.ArgumentNotNull(newRepository, "newRepository");
            if (string.IsNullOrEmpty(newRepository.Name))
                throw new ArgumentException("The new repository's name must not be null.");

            return ApiConnection.Post<Repository>(ApiUrls.OrganizationRepositories(organizationLogin), newRepository);
        }

        /// <summary>
        /// Deletes the specified repository.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#delete-a-repository">API documentation</a> for more information.
        /// Deleting a repository requires admin access. If OAuth is used, the `delete_repo` scope is required.
        /// </remarks>
        /// <param name="owner">The owner of the repository.</param>
        /// <param name="name">The name of the repository.</param>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        public Task Delete(string owner, string name)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            var endpoint = "repos/{0}/{1}".FormatUri(owner, name);
            return ApiConnection.Delete(endpoint);
        }

        /// <summary>
        /// Gets the specified repository.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#get">API documentation</a> for more information.
        /// </remarks>
        /// <param name="owner">The owner of the repository.</param>
        /// <param name="name">The name of the repository.</param>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns>A <see cref="Repository"/></returns>
        public Task<Repository> Get(string owner, string name)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            var endpoint = "repos/{0}/{1}".FormatUri(owner, name);
            return ApiConnection.Get<Repository>(endpoint);
        }

        /// <summary>
        /// Gets all repositories owned by the current user.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#list-your-repositories">API documentation</a> for more information.
        /// The default page size on GitHub.com is 30.
        /// </remarks>
        /// <exception cref="AuthorizationException">Thrown if the client is not authenticated.</exception>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns>A <see cref="IReadOnlyPagedCollection{Repository}"/> of <see cref="Repository"/>.</returns>
        public Task<IReadOnlyList<Repository>> GetAllForCurrent()
        {
            return ApiConnection.GetAll<Repository>(ApiUrls.Repositories());
        }

        /// <summary>
        /// Gets all repositories owned by the specified user.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#list-user-repositories">API documentation</a> for more information.
        /// The default page size on GitHub.com is 30.
        /// </remarks>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns>A <see cref="IReadOnlyPagedCollection{Repository}"/> of <see cref="Repository"/>.</returns>
        public Task<IReadOnlyList<Repository>> GetAllForUser(string login)
        {
            Ensure.ArgumentNotNullOrEmptyString(login, "login");

            return ApiConnection.GetAll<Repository>(ApiUrls.Repositories(login));
        }

        /// <summary>
        /// Gets all repositories owned by the specified organization.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/#list-organization-repositories">API documentation</a> for more information.
        /// The default page size on GitHub.com is 30.
        /// </remarks>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns>A <see cref="IReadOnlyPagedCollection{Repository}"/> of <see cref="Repository"/>.</returns>
        public Task<IReadOnlyList<Repository>> GetAllForOrg(string organization)
        {
            Ensure.ArgumentNotNullOrEmptyString(organization, "organization");

            return ApiConnection.GetAll<Repository>(ApiUrls.OrganizationRepositories(organization));
        }

        /// <summary>
        /// Gets the preferred README for the specified repository.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/contents/#get-the-readme">API documentation</a> for more information.
        /// </remarks>
        /// <param name="owner">The owner of the repository.</param>
        /// <param name="name">The name of the repository.</param>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns></returns>
        public async Task<Readme> GetReadme(string owner, string name)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            var endpoint = "repos/{0}/{1}/readme".FormatUri(owner, name);
            var readmeInfo = await ApiConnection.Get<ReadmeResponse>(endpoint, null).ConfigureAwait(false);
            return new Readme(readmeInfo, ApiConnection);
        }

        /// <summary>
        /// Gets the perferred README's HTML for the specified repository.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/contents/#get-the-readme">API documentation</a> for more information.
        /// </remarks>
        /// <param name="owner">The owner of the repository.</param>
        /// <param name="name">The name of the repository.</param>
        /// <exception cref="ApiException">Thrown when a general API error occurs.</exception>
        /// <returns></returns>
        public Task<string> GetReadmeHtml(string owner, string name)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");

            var endpoint = "repos/{0}/{1}/readme".FormatUri(owner, name);
            return ApiConnection.GetHtml(endpoint, null);
        }

        /// <summary>
        /// A client for GitHub's Commit Status API.
        /// </summary>
        /// <remarks>
        /// See the <a href="http://developer.github.com/v3/repos/statuses/">Commit Status API documentation</a> for more
        /// details. Also check out the <a href="https://github.com/blog/1227-commit-status-api">blog post</a> 
        /// that announced this feature.
        /// </remarks>
        public ICommitStatusClient CommitStatus { get; private set; }

        Lazy<IRepositoryHooksClient> _hooks;

        /// <summary>
        /// Gets a client for GitHub's Repository Hooks
        /// </summary>
        public IRepositoryHooksClient Hooks
        {
            get { return _hooks.Value; }
        }
    }
}