using System.Net.Http.Json;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using UniVerse.Application.DTOs.Sync;
using UniVerse.Application.Interfaces;

namespace UniVerse.Infrastructure.ExternalServices;

public class ModeusApiClient : IModeusApiClient
{
    private readonly HttpClient _http;
    private readonly ILogger<ModeusApiClient> _logger;

    public ModeusApiClient(HttpClient http, IConfiguration config, ILogger<ModeusApiClient> logger)
    {
        _http = http; _logger = logger;
        var apiKey = config["ModeusApi:ApiKey"];
        if (!string.IsNullOrEmpty(apiKey))
            _http.DefaultRequestHeaders.Add("X-API-Key", apiKey);
    }

    public async Task<ModeusEventsResponse> SearchEventsAsync(SyncScheduleRequest request)
    {
        var body = new { specialtyCode = request.SpecialtyCode, timeMin = request.TimeMin, timeMax = request.TimeMax, typeId = request.TypeId };
        var response = await _http.PostAsJsonAsync("/api/proxy/events/search", body);
        await EnsureSuccessAsync(response, "Modeus events search",
            $"specialtyCode={request.SpecialtyCode ?? "<empty>"}, timeMin={request.TimeMin:O}, timeMax={request.TimeMax:O}, typeId=[{string.Join(", ", request.TypeId ?? [])}]");
        return await response.Content.ReadFromJsonAsync<ModeusEventsResponse>() ?? new(new());
    }

    public async Task<ModeusRoomsResponse> SearchRoomsAsync()
    {
        const int pageSize = 100;
        var allRooms = new List<ModeusRoom>();
        var page = 0;
        var totalPages = 1;

        do
        {
            var body = new
            {
                name = "",
                sort = "+building.name,+name",
                size = pageSize,
                page,
                deleted = false
            };

            var response = await _http.PostAsJsonAsync("/api/proxy/rooms/search", body);
            await EnsureSuccessAsync(response, "Modeus rooms search",
                $"name=<empty>, sort=+building.name,+name, size={pageSize}, page={page}, deleted=false");

            var payload = await response.Content.ReadFromJsonAsync<ModeusRoomsResponse>() ?? new ModeusRoomsResponse();
            allRooms.AddRange(payload.RoomItems);

            totalPages = payload.Page?.TotalPages ?? page + 1;
            page++;
        }
        while (page < totalPages);

        return new ModeusRoomsResponse { Rooms = allRooms };
    }

    private static async Task EnsureSuccessAsync(HttpResponseMessage response, string operation, string requestSummary)
    {
        if (response.IsSuccessStatusCode) return;

        var responseBody = await response.Content.ReadAsStringAsync();
        if (responseBody.Length > 2000)
            responseBody = string.Concat(responseBody.AsSpan(0, 2000), "...<truncated>");

        throw new HttpRequestException(
            $"{operation} failed with HTTP {(int)response.StatusCode} {response.ReasonPhrase}. Request: {requestSummary}. Response body: {responseBody}",
            null,
            response.StatusCode);
    }

    public async Task<List<ModeusEmployee>> SearchEmployeeAsync(string fullname)
    {
        var response = await _http.GetFromJsonAsync<List<ModeusEmployee>>(
            $"/api/schedule/searchemployee?fullname={Uri.EscapeDataString(fullname)}");
        return response ?? new();
    }
}