using System;
using System.Collections.Generic;
using System.Linq;
using StardewModdingAPI;
using StardewValley;
using StardewValley.Objects;
using TrainerMod.Framework.ItemData;

namespace TrainerMod.Framework.Commands.Player
{
    /// <summary>A command which list items available to spawn.</summary>
    internal class ListItemsCommand : TrainerCommand
    {
        /*********
        ** Public methods
        *********/
        /// <summary>Construct an instance.</summary>
        public ListItemsCommand()
            : base("list_items", "Lists and searches items in the game data.\n\nUsage: list_items [search]\n- search (optional): an arbitrary search string to filter by.") { }

        /// <summary>Handle the command.</summary>
        /// <param name="monitor">Writes messages to the console and log file.</param>
        /// <param name="command">The command name.</param>
        /// <param name="args">The command arguments.</param>
        public override void Handle(IMonitor monitor, string command, ArgumentParser args)
        {
            var matches = this.GetItems(args.ToArray()).ToArray();

            // show matches
            string summary = "Searching...\n";
            if (matches.Any())
                monitor.Log(summary + this.GetTableString(matches, new[] { "type", "id", "name" }, val => new[] { val.Type.ToString(), val.ID.ToString(), val.Name }), LogLevel.Info);
            else
                monitor.Log(summary + "No items found", LogLevel.Info);
        }


        /*********
        ** Private methods
        *********/
        /// <summary>Get all items which can be searched and added to the player's inventory through the console.</summary>
        /// <param name="searchWords">The search string to find.</param>
        private IEnumerable<ISearchItem> GetItems(string[] searchWords)
        {
            // normalise search term
            searchWords = searchWords?.Where(word => !string.IsNullOrWhiteSpace(word)).ToArray();
            if (searchWords?.Any() == false)
                searchWords = null;

            // find matches
            return (
                from item in this.GetItems()
                let term = $"{item.ID}|{item.Type}|{item.Name}"
                where searchWords == null || searchWords.All(word => term.IndexOf(word, StringComparison.CurrentCultureIgnoreCase) != -1)
                select item
            );
        }

        /// <summary>Get all items which can be searched and added to the player's inventory through the console.</summary>
        private IEnumerable<ISearchItem> GetItems()
        {
            // objects
            foreach (int id in Game1.objectInformation.Keys)
            {
                ISearchItem obj = id >= Ring.ringLowerIndexRange && id <= Ring.ringUpperIndexRange
                    ? new SearchableRing(id)
                    : (ISearchItem)new SearchableObject(id);
                if (obj.IsValid)
                    yield return obj;
            }

            // weapons
            foreach (int id in Game1.content.Load<Dictionary<int, string>>("Data\\weapons").Keys)
            {
                ISearchItem weapon = new SearchableWeapon(id);
                if (weapon.IsValid)
                    yield return weapon;
            }
        }

        /// <summary>Get an ASCII table for a set of tabular data.</summary>
        /// <typeparam name="T">The data type.</typeparam>
        /// <param name="data">The data to display.</param>
        /// <param name="header">The table header.</param>
        /// <param name="getRow">Returns a set of fields for a data value.</param>
        private string GetTableString<T>(IEnumerable<T> data, string[] header, Func<T, string[]> getRow)
        {
            // get table data
            int[] widths = header.Select(p => p.Length).ToArray();
            string[][] rows = data
                .Select(item =>
                {
                    string[] fields = getRow(item);
                    if (fields.Length != widths.Length)
                        throw new InvalidOperationException($"Expected {widths.Length} columns, but found {fields.Length}: {string.Join(", ", fields)}");

                    for (int i = 0; i < fields.Length; i++)
                        widths[i] = Math.Max(widths[i], fields[i].Length);

                    return fields;
                })
                .ToArray();

            // render fields
            List<string[]> lines = new List<string[]>(rows.Length + 2)
            {
                header,
                header.Select((value, i) => "".PadRight(widths[i], '-')).ToArray()
            };
            lines.AddRange(rows);

            return string.Join(
                Environment.NewLine,
                lines.Select(line => string.Join(" | ",
                    line.Select((field, i) => field.PadRight(widths[i], ' ')).ToArray())
                )
            );
        }
    }
}