using System;
using System.Collections.Generic;
using System.IO;
using UnityEngine;

namespace Ironspore
{
    [Serializable]
    public sealed class CargoStack
    {
        public string uid = Guid.NewGuid().ToString("N");
        public string itemId;
        public int count;
        public int x, y;
        public bool rotated, borrowed;
        public CargoStack(string id, int amount)
        {
            itemId = id;
            count = amount;
        }
        public string Name => InventoryGrid.Slot(itemId) >= 0 ? GameLocalization.Text("equipment." + itemId + ".name") : GameLocalization.ItemName(itemId);
    }

    [Serializable]
    public sealed class RunRecord
    {
        public string id;
        public bool active;
        public int seed;
        public int stage;
        public int branch;
        public int biome;
        public int chassis = 1;
        public int[] equipment = { 0, 0, 0, 0 };
        public float armor;
        public float energy = 100;
        public bool podUsed;
        public bool objectiveDone;
        public bool routeCompleted;
        public int upgrades;
        public float elapsed;
        public float escortArmor = 250;
        public List<CargoStack> cargo = new List<CargoStack>();
        public List<CargoStack> safeCase = new List<CargoStack>();
        public List<CargoStack> installed = new List<CargoStack>();
        public bool destructionPending;
        public List<string> searched = new List<string>();
    }

    [Serializable]
    public sealed class GameSave
    {
        public const int CurrentVersion = 2;
        public int version = CurrentVersion;
        public List<CargoStack> warehouse = new List<CargoStack>();
        public int alloy;
        public int cells;
        public int sorties;
        public int extractions;
        public int completed;
        public List<string> blueprints = new List<string>();
        public List<string> unlocked = new List<string>();
        public List<string> receipts = new List<string>();
        public RunRecord run = new RunRecord();
    }

    public sealed partial class ProfileStore
    {
        readonly string path;
        public GameSave Data
        {
            get; private set;
        }
        public string Error
        {
            get; private set;
        }

        public static string SavePath(bool trial)
        {
#if UNITY_EDITOR
            string root = Path.Combine(Path.GetDirectoryName(Application.dataPath), "UserSettings");
#else
            string root = Application.persistentDataPath;
#endif
            return Path.Combine(root, "Ironspore", trial ? "range-v2.json" : "profile-v2.json");
        }

        public ProfileStore(string savePath)
        {
            path = savePath;
            Data = Load(path) ?? Load(path + ".bak");
            if (Data == null)
            {
                if (File.Exists(path) || File.Exists(path + ".bak"))
                    throw new InvalidDataException("No valid equipment snapshot: " + path);
                Data = new GameSave();
                for (int slot = 0; slot < 4; slot++)
                    Data.warehouse.Add(new CargoStack(InventoryGrid.EquipmentId(slot, 0), 1));
            }
        }

        static GameSave Load(string file)
        {
            try
            {
                if (!File.Exists(file))
                    return null;
                var save = JsonUtility.FromJson<GameSave>(File.ReadAllText(file));
                if (save != null && save.version != GameSave.CurrentVersion)
                    throw new NotSupportedException("Unsupported equipment save version: " + save.version);
                if (!Valid(save)) return null;
                return save;
            }
            catch (ArgumentException) { return null; }
        }

        public bool Commit(Func<GameSave, bool> change)
        {
            if (Data.run.destructionPending) return false;
            return Write(change);
        }

        bool Write(Func<GameSave, bool> change)
        {
            Error = null;
            var candidate = JsonUtility.FromJson<GameSave>(JsonUtility.ToJson(Data));
            if (!change(candidate) || !Valid(candidate))
                return false;
            try
            {
                Directory.CreateDirectory(Path.GetDirectoryName(path));
                string temp = path + ".tmp";
                using (var stream = new FileStream(temp, FileMode.Create, FileAccess.Write, FileShare.None))
                {
                    byte[] bytes = System.Text.Encoding.UTF8.GetBytes(JsonUtility.ToJson(candidate, true));
                    stream.Write(bytes, 0, bytes.Length);
                    stream.Flush(true);
                }
                if (File.Exists(path))
                    File.Replace(temp, path, Load(path) == null ? null : path + ".bak");
                else
                    File.Move(temp, path);
                Data = candidate;
                Error = null;
                return true;
            }
            catch (Exception ex) { Error = ex.Message; return false; }
        }

        public bool Begin(int chassis, int[] equipment, float armor, int seed, bool trial = false, string[] selected = null)
        {
            return Commit(s =>
            {
                if ((selected != null && selected.Length != 4) || s.run.active || equipment == null || equipment.Length != 4 || armor <= 0) return false;
                s.run = new RunRecord { id = Guid.NewGuid().ToString("N"), active = true, seed = seed, chassis = chassis, equipment = (int[])equipment.Clone(), armor = armor };
                for (int slot = 0; slot < 4; slot++)
                {
                    string id = InventoryGrid.EquipmentId(slot, equipment[slot]);
                    if (id == null) return false;
                    var requested = selected?[slot];
                    var item = s.warehouse.Find(part => part.itemId == id && (requested == null || requested == part.uid));
                    if (item == null)
                    {
                        if (requested != null || (!trial && equipment[slot] != 0)) return false;
                        item = new CargoStack(id, 1) { borrowed = true };
                    }
                    else s.warehouse.Remove(item);
                    s.run.installed.Add(item);
                }
                s.sorties++;
                return true;
            });
        }

        public bool CompleteRoute()
        {
            return Commit(s =>
            {
                if (!s.run.active || s.run.armor <= 0 || s.run.routeCompleted)
                    return false;
                s.run.routeCompleted = true;
                s.run.objectiveDone = true;
                s.completed++;
                return true;
            });
        }
    }
}