using System;
using System.IO;
using System.Text.Json;
using CounterDrone.Core;
using CounterDrone.Core.Algorithms;
using CounterDrone.Core.Services;
using Xunit;

namespace CounterDrone.Core.Tests
{
    public class ConfigServiceTests : IDisposable
    {
        private readonly string _testDir;
        private readonly IPathProvider _paths;
        private readonly ConfigService _config;
        private readonly SQLite.SQLiteConnection _db;

        public ConfigServiceTests()
        {
            _testDir = Path.Combine(Path.GetTempPath(), $"cd_cfg_{Guid.NewGuid():N}");
            _paths = new TestPathProvider(_testDir);
            var dbm = new DatabaseManager(_paths);
            _db = dbm.OpenMainDb();
            _config = new ConfigService(_paths, _db);
        }

        public void Dispose()
        {
            _db?.Close();
            if (Directory.Exists(_testDir)) Directory.Delete(_testDir, true);
        }

        [Fact]
        public void GetPlannerConfigJson_ReturnsValidJson()
        {
            var json = _config.GetPlannerConfigJson();
            var cfg = JsonSerializer.Deserialize<PlannerConfig>(json, new JsonSerializerOptions
            {
                Converters = { new System.Text.Json.Serialization.JsonStringEnumConverter() },
                PropertyNameCaseInsensitive = true,
            });
            Assert.NotNull(cfg);
            Assert.True(cfg.CloudOverlapRatio >= 0);
        }

        [Fact]
        public void SavePlannerConfig_PersistsAndReloads()
        {
            var original = _config.GetPlannerConfigJson();
            var cfg = JsonSerializer.Deserialize<PlannerConfig>(original, new JsonSerializerOptions
            {
                Converters = { new System.Text.Json.Serialization.JsonStringEnumConverter() },
                PropertyNameCaseInsensitive = true,
            })!;
            cfg.CloudOverlapRatio = 0.3f;
            var modifiedJson = JsonSerializer.Serialize(cfg, new JsonSerializerOptions
            {
                Converters = { new System.Text.Json.Serialization.JsonStringEnumConverter() },
            });

            _config.SavePlannerConfig(modifiedJson);

            var reloaded = _config.GetPlannerConfigJson();
            var reloadedCfg = JsonSerializer.Deserialize<PlannerConfig>(reloaded, new JsonSerializerOptions
            {
                Converters = { new System.Text.Json.Serialization.JsonStringEnumConverter() },
                PropertyNameCaseInsensitive = true,
            })!;
            Assert.Equal(0.3f, reloadedCfg.CloudOverlapRatio);
        }

        [Fact]
        public void PlannerConfigReloaded_EventFires()
        {
            PlannerConfig? received = null;
            _config.PlannerConfigReloaded += cfg => received = cfg;

            var json = _config.GetPlannerConfigJson();
            _config.SavePlannerConfig(json);

            Assert.NotNull(received);
            Assert.True(received.CloudOverlapRatio >= 0);
        }

        [Fact]
        public void Reload_FromDiskRefreshesConfig()
        {
            // 直接改文件
            var path = Path.Combine(_testDir, "planner_config.json");
            var json = File.ReadAllText(path);
            var cfg = JsonSerializer.Deserialize<PlannerConfig>(json, new JsonSerializerOptions
            {
                Converters = { new System.Text.Json.Serialization.JsonStringEnumConverter() },
                PropertyNameCaseInsensitive = true,
            })!;
            cfg.ExpansionFactor = 0.8f;
            File.WriteAllText(path, JsonSerializer.Serialize(cfg, new JsonSerializerOptions
            {
                Converters = { new System.Text.Json.Serialization.JsonStringEnumConverter() },
            }));

            PlannerConfig? received = null;
            _config.PlannerConfigReloaded += cfg => received = cfg;

            _config.Reload();

            Assert.NotNull(received);
            Assert.Equal(0.8f, received.ExpansionFactor);
        }

        [Fact]
        public void GetDefaultsJson_ReturnsValidJson()
        {
            var json = _config.GetDefaultsJson();
            Assert.Contains("ammunition", json.ToLower());
        }
    }
}