using System.Collections.Generic;
using System.Linq;
using Comal.Classes;
using InABox.Clients;
using InABox.Core;

namespace PRSServer
{
    /// <summary>
    ///     Provides an interface for interacting with the database's WebTemplates and WebStyles
    /// </summary>
    public class WebDatabaseInterface
    {
        /// <summary>
        ///     Gets a WebTemplate class by its slug and associated data model
        /// </summary>
        /// <param name="dataModel">The datamodel associated</param>
        /// <param name="slug">The slug of the URL</param>
        /// <returns>A WebTemplate if it exists, null otherwise</returns>
        public static WebTemplate? GetWebTemplateByDataModelAndSlug(string dataModel, string slug)
        {
            var htmlTable = new Client<WebTemplate>().Query(
                new Filter<WebTemplate>(x => x.Slug).IsEqualTo(slug).And(x => x.DataModel).IsEqualTo(dataModel),
                Columns.None<WebTemplate>().Add(x => x.ID).Add(x => x.Template)
            );

            if (htmlTable.Rows.Count > 1)
            {
                Logger.Send(LogType.Error, ClientFactory.UserID,
                    "Ambiguous request; multiple template pages with the given data model '" + dataModel + "' and slug '" + slug + "'");
                return null;
            }

            if (htmlTable.Rows.Count == 0) return null;

            return htmlTable.Rows[0].ToObject<WebTemplate>();
        }

        /// <summary>
        ///     Gets a WebTemplate class by its slug, where the DataModel is empty
        /// </summary>
        /// <param name="slug">The slug of the URL</param>
        /// <returns>A WebTemplate if it exists, null otherwise</returns>
        public static WebTemplate? GetWebTemplateBySlug(string slug)
        {
            var htmlTable = new Client<WebTemplate>().Query(
                new Filter<WebTemplate>(x => x.Slug).IsEqualTo(slug).And(x => x.DataModel).IsEqualTo(""),
                Columns.None<WebTemplate>().Add(x => x.ID).Add(x => x.Template)
            );

            if (htmlTable.Rows.Count > 1)
            {
                Logger.Send(LogType.Error, ClientFactory.UserID,
                    "Ambiguous request; multiple template pages with the slug '" + slug + "'");
                return null;
            }

            if (htmlTable.Rows.Count == 0) return null;

            return htmlTable.Rows[0].ToObject<WebTemplate>();
        }

        /// <summary>
        ///     Accesses the stylesheets associated with the codes 'stylesheetCodes'
        /// </summary>
        /// <param name="stylesheetCodes">A list of stylesheet codes</param>
        /// <returns>A dictionary with 'Code => Style' entries</returns>
        public static Dictionary<string, WebStyle> GetStylesheets(params string[] stylesheetCodes)
        {
            var stylesTable = new Client<WebStyle>().Query(
                new Filter<WebStyle>(x => x.Code).InList(stylesheetCodes.ToArray()),
                Columns.None<WebStyle>().Add(x => x.ID).Add(x => x.Code).Add(x => x.Style)
            );

            var stylesheets = new Dictionary<string, WebStyle>();
            foreach (var row in stylesTable.Rows)
            {
                var webStyle = row.ToObject<WebStyle>();
                stylesheets[webStyle.Code] = webStyle;
            }

            return stylesheets;
        }

        /// <summary>
        ///     If getting multiple stylesheets, do not use this function; use GetStylesheets() instead - it is more efficient
        /// </summary>
        /// <param name="stylesheetCode">The code associated with the requested stylesheet</param>
        /// <returns>The stylesheet associated with the code if it exists, null otherwise</returns>
        public static WebStyle? GetStylesheet(string stylesheetCode)
        {
            var stylesTable = new Client<WebStyle>().Query(
                new Filter<WebStyle>(x => x.Code).IsEqualTo(stylesheetCode),
                Columns.None<WebStyle>().Add(x => x.ID).Add(x => x.Code).Add(x => x.Style)
            );
            return stylesTable.Rows.ElementAtOrDefault(0)?.ToObject<WebStyle>();
        }
    }
}