using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using RPGCore.Core;
using UnityEngine;

namespace RPGCore.GlobalModules.ProfileManagerGlobalModule
{
    [Serializable]
    public class ProfileManagerModule : GlobalModule
    {
        // Paths
        private static string directoryPath => Path.Combine(Application.persistentDataPath, "profiles");
        private static string fileNameTemplate => "{0}_{1}.profile";
        private static string fileNameMask => "*.profile";
        private static string fileNameWithDefaultProfile => "default";
        
        // Runtime
        private Profile _activeProfile;
        public event Action<Profile> OnProfileChange; 

        public Profile<T> LoadDefault<T>() where T : class
        {
            var defaultPath = Path.Combine(directoryPath, fileNameWithDefaultProfile);
            
            // Default file not found
            if (!File.Exists(defaultPath)) return null;
            var guid = File.ReadAllText(defaultPath);
            
            // Profile not found, by guid from default file
            var file = Directory.GetFiles(directoryPath, string.Format(fileNameTemplate, "*", guid)).FirstOrDefault();
            if (file == null) return null;

            return JsonUtility.FromJson<Profile<T>>(File.ReadAllText(file));
        }

        /// <summary>
        /// Gets currently active profile
        /// </summary>
        public Profile<T> Get<T>() where T : class
        {
            return _activeProfile as Profile<T>;
        }
        
        /// <summary>
        /// Parse all profiles from files and returns them.
        /// There is no caching, it will scan files everytime it is called.
        /// </summary>
        public List<Profile<T>> LoadAll<T>() where T : class
        {
            if (!Directory.Exists(directoryPath)) Directory.CreateDirectory(directoryPath);

            return Directory.GetFiles(directoryPath, fileNameMask)
                .Select(File.ReadAllText)
                .Select(JsonUtility.FromJson<Profile<T>>)
                .ToList();
        }

        /// <summary>
        /// Creates new profile with given name and saves it as file.
        /// </summary>
        public Profile<T> Create<T>(string name) where T : class
        {
            if (!Directory.Exists(directoryPath)) Directory.CreateDirectory(directoryPath);

            var newProfile = Activator.CreateInstance<Profile<T>>();
            newProfile.name = name;
            Save(newProfile);
            
            return newProfile;
        }

        /// <summary>
        /// Removes given profile from files and if its currently active unselects it.
        /// </summary>
        /// <param name="playerProfile"></param>
        public void Delete<T>(Profile<T> playerProfile) where T : class
        {
            if (playerProfile == _activeProfile) Select<T>(null);
            
            if (!Directory.Exists(directoryPath)) Directory.CreateDirectory(directoryPath);
            
            File.Delete(GetFullPathFor(playerProfile));
        }
        
        /// <summary>
        /// Saves currently active profile as file.
        /// </summary>
        public void Save()
        {
            Save(_activeProfile);
        }
        
        /// <summary>
        /// Saves given profile as file.
        /// </summary>
        private void Save(Profile profile)
        {
            if (!Directory.Exists(directoryPath)) Directory.CreateDirectory(directoryPath);
            File.WriteAllText(GetFullPathFor(profile), JsonUtility.ToJson(profile, true));
        }

        /// <summary>
        /// Set active given profile. Will be selected automatically next time.
        /// </summary>
        public void Select<T>(Profile<T> playerProfile) where T : class
        {
            _activeProfile = playerProfile;
            OnProfileChange?.Invoke(_activeProfile);

            // No profile found - create it for user
            _activeProfile ??= Create<T>("New Profile");
            
            // Our selected profile will be default one when starting game again
            File.WriteAllText(Path.Combine(directoryPath, fileNameWithDefaultProfile), _activeProfile.guid);
        }

        private string GetFullPathFor(Profile playerProfile)
        {
            var fileName = string.Format(fileNameTemplate, playerProfile.name, playerProfile.guid);
            return Path.Combine(directoryPath, fileName);
        }
    }
}