using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using StardewModdingAPI.Web.Framework.LogParsing.Models;

namespace StardewModdingAPI.Web.ViewModels
{
    /// <summary>The view model for the log parser page.</summary>
    public class LogParserModel
    {
        /*********
        ** Fields
        *********/
        /// <summary>A regex pattern matching characters to remove from a mod name to create the slug ID.</summary>
        private readonly Regex SlugInvalidCharPattern = new Regex("[^a-z0-9]", RegexOptions.Compiled | RegexOptions.IgnoreCase);


        /*********
        ** Accessors
        *********/
        /// <summary>The root URL for the log parser controller.</summary>
        public string SectionUrl { get; set; }

        /// <summary>The paste ID.</summary>
        public string PasteID { get; set; }

        /// <summary>The parsed log info.</summary>
        public ParsedLog ParsedLog { get; set; }

        /// <summary>Whether to show the raw unparsed log.</summary>
        public bool ShowRaw { get; set; }

        /// <summary>An error which occurred while uploading the log to Pastebin.</summary>
        public string UploadError { get; set; }

        /// <summary>An error which occurred while parsing the log file.</summary>
        public string ParseError => this.ParsedLog?.Error;


        /*********
        ** Public methods
        *********/
        /// <summary>Construct an instance.</summary>
        public LogParserModel() { }

        /// <summary>Construct an instance.</summary>
        /// <param name="sectionUrl">The root URL for the log parser controller.</param>
        /// <param name="pasteID">The paste ID.</param>
        public LogParserModel(string sectionUrl, string pasteID)
        {
            this.SectionUrl = sectionUrl;
            this.PasteID = pasteID;
            this.ParsedLog = null;
            this.ShowRaw = false;
        }

        /// <summary>Construct an instance.</summary>
        /// <param name="sectionUrl">The root URL for the log parser controller.</param>
        /// <param name="pasteID">The paste ID.</param>
        /// <param name="parsedLog">The parsed log info.</param>
        /// <param name="showRaw">Whether to show the raw unparsed log.</param>
        public LogParserModel(string sectionUrl, string pasteID, ParsedLog parsedLog, bool showRaw)
            : this(sectionUrl, pasteID)
        {
            this.ParsedLog = parsedLog;
            this.ShowRaw = showRaw;
        }

        /// <summary>Get all content packs in the log grouped by the mod they're for.</summary>
        public IDictionary<string, LogModInfo[]> GetContentPacksByMod()
        {
            // get all mods & content packs
            LogModInfo[] mods = this.ParsedLog?.Mods;
            if (mods == null || !mods.Any())
                return new Dictionary<string, LogModInfo[]>();

            // group by mod
            return mods
                .Where(mod => mod.ContentPackFor != null)
                .GroupBy(mod => mod.ContentPackFor)
                .ToDictionary(group => group.Key, group => group.ToArray());
        }

        /// <summary>Get a sanitised mod name that's safe to use in anchors, attributes, and URLs.</summary>
        /// <param name="modName">The mod name.</param>
        public string GetSlug(string modName)
        {
            return this.SlugInvalidCharPattern.Replace(modName, "");
        }
    }
}