using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

namespace XafPet.Desktop.PetEngine;

/// <summary>CFC 后端 API 客户端。所有接口统一 POST + JWT Bearer。</summary>
public sealed class ApiClient
{
    private readonly HttpClient _http;
    private readonly string _baseUrl;
    private string _token;

    private static readonly JsonSerializerOptions JsonOpts = new(JsonSerializerDefaults.Web);

    public ApiClient(HttpClient http, string baseUrl, string token)
    {
        _http = http;
        _baseUrl = baseUrl.TrimEnd('/');
        _token = token;
    }

    public void UpdateToken(string token) => _token = token;

    private async Task<T?> PostAsync<T>(string path, object? body = null)
    {
        using var req = new HttpRequestMessage(HttpMethod.Post, $"{_baseUrl}{path}");
        req.Headers.Authorization = new AuthenticationHeaderValue("Bearer", _token);
        if (body != null)
        {
            req.Content = new StringContent(JsonSerializer.Serialize(body, JsonOpts),
                Encoding.UTF8, "application/json");
        }
        var resp = await _http.SendAsync(req);
        var json = await resp.Content.ReadAsStringAsync();
        var result = JsonSerializer.Deserialize<ApiResult<T>>(json, JsonOpts)
            ?? throw new ApiException(-1, "响应解析失败");
        if (!result.IsSuccess)
            throw new ApiException(result.Code, result.Message ?? "未知错误");
        return result.Data;
    }

    /// <summary>POST /api/tasks/today — 今日任务</summary>
    public Task<List<CfcTask>?> GetTodayTasksAsync()
        => PostAsync<List<CfcTask>>("/api/tasks/today", new Dictionary<string, object>());

    /// <summary>POST /api/energy/overview — 五维能量概览</summary>
    public Task<EnergyOverview?> GetEnergyOverviewAsync()
        => PostAsync<EnergyOverview>("/api/energy/overview");

    /// <summary>POST /api/daily/checkin — 今日打卡状态</summary>
    public Task<DailyCheckin?> GetDailyCheckinAsync()
        => PostAsync<DailyCheckin>("/api/daily/checkin");

    /// <summary>POST /api/daily/checkin — 完成喝水打卡（body: {"type":"water"}）</summary>
    public async Task<ApiResult<object>?> CompleteDrinkWaterAsync()
    {
        using var req = new HttpRequestMessage(HttpMethod.Post, $"{_baseUrl}/api/daily/checkin");
        req.Headers.Authorization = new AuthenticationHeaderValue("Bearer", _token);
        req.Content = new StringContent("""{"type":"water"}""", Encoding.UTF8, "application/json");
        var resp = await _http.SendAsync(req);
        var json = await resp.Content.ReadAsStringAsync();
        var result = JsonSerializer.Deserialize<ApiResult<object>>(json, JsonOpts)
            ?? throw new ApiException(-1, "响应解析失败");
        if (!result.IsSuccess)
            throw new ApiException(result.Code, result.Message ?? "未知错误");
        return result;
    }

    /// <summary>POST /api/user/mascot/get — 获取用户已选吉祥物</summary>
    public Task<MascotInfo?> GetMascotAsync()
        => PostAsync<MascotInfo>("/api/user/mascot/get");

    /// <summary>POST /api/user/mascot/set — 设置吉祥物</summary>
    public Task<object?> SetMascotAsync(string mascotId)
        => PostAsync<object>("/api/user/mascot/set", new { mascotId });

}