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

namespace DNFLoadout;

internal sealed class ServerClient
{
    private readonly HttpClient _http = new() { Timeout = TimeSpan.FromSeconds(10) };
    private readonly Config _config;

    public ServerClient(Config config) => _config = config;

    private HttpRequestMessage Request(HttpMethod method, string path)
    {
        var req = new HttpRequestMessage(method, _config.ServerUrl.TrimEnd('/') + path);
        if (!string.IsNullOrWhiteSpace(_config.AdminToken))
            req.Headers.TryAddWithoutValidation("X-Admin-Token", _config.AdminToken.Trim());
        return req;
    }

    public async Task<List<SlotItem>> GetEquipmentAsync(string characterName)
    {
        using var req = Request(HttpMethod.Get,
            "/local/dnf-gm/loadout/equipment?character_id=" + Uri.EscapeDataString(characterName.Trim()));
        using var resp = await _http.SendAsync(req);
        var text = await resp.Content.ReadAsStringAsync();
        if (!resp.IsSuccessStatusCode) throw new Exception(text);
        var envelope = JsonSerializer.Deserialize<Envelope<SnapshotData>>(text)
            ?? throw new Exception("empty response");
        if (!envelope.Ok) throw new Exception(envelope.Error ?? "server returned failure");
        return envelope.Data?.Slots ?? new List<SlotItem>();
    }

    public async Task<List<CharacterInfo>> GetCharactersAsync()
    {
        using var req = Request(HttpMethod.Get, "/local/dnf-gm/characters");
        using var resp = await _http.SendAsync(req);
        var text = await resp.Content.ReadAsStringAsync();
        if (!resp.IsSuccessStatusCode) throw new Exception(text);
        var envelope = JsonSerializer.Deserialize<Envelope<List<CharacterInfo>>>(text)
            ?? throw new Exception("empty response");
        if (!envelope.Ok) throw new Exception(envelope.Error ?? "server returned failure");
        return envelope.Data ?? new List<CharacterInfo>();
    }

    internal sealed class CharacterInfo
    {
        [JsonPropertyName("character_id")] public string CharacterId { get; set; } = "";
        [JsonPropertyName("name")] public string Name { get; set; } = "";
        [JsonPropertyName("online")] public bool Online { get; set; }
    }

    public async Task<ApplyData> ApplyAsync(string characterName, IEnumerable<SlotItem> slots)
    {
        var body = new ApplyRequest
        {
            CharacterId = characterName.Trim(),
            Slots = slots.ToList(),
        };
        using var req = Request(HttpMethod.Post, "/local/dnf-gm/loadout/apply");
        req.Content = JsonContent.Create(body);
        using var resp = await _http.SendAsync(req);
        var text = await resp.Content.ReadAsStringAsync();
        if (!resp.IsSuccessStatusCode) throw new Exception(text);
        var envelope = JsonSerializer.Deserialize<Envelope<ApplyData>>(text)
            ?? throw new Exception("empty response");
        if (!envelope.Ok) throw new Exception(envelope.Error ?? "server returned failure");
        return envelope.Data ?? new ApplyData();
    }

    private sealed class Envelope<T>
    {
        [JsonPropertyName("ok")] public bool Ok { get; set; }
        [JsonPropertyName("error")] public string? Error { get; set; }
        [JsonPropertyName("data")] public T? Data { get; set; }
    }

    private sealed class SnapshotData
    {
        [JsonPropertyName("character_id")] public string CharacterId { get; set; } = "";
        [JsonPropertyName("online")] public bool Online { get; set; }
        [JsonPropertyName("slots")] public List<SlotItem> Slots { get; set; } = new();
    }

    private sealed class ApplyRequest
    {
        [JsonPropertyName("character_id")] public string CharacterId { get; set; } = "";
        [JsonPropertyName("slots")] public List<SlotItem> Slots { get; set; } = new();
    }

    internal sealed class ApplyData
    {
        [JsonPropertyName("applied")] public List<SlotItem>? Applied { get; set; } = new();
        [JsonPropertyName("skipped")] public List<SkipData>? Skipped { get; set; } = new();
        [JsonPropertyName("refresh_sent")] public bool RefreshSent { get; set; }
        [JsonPropertyName("refresh_error")] public string? RefreshError { get; set; }
        [JsonPropertyName("cooldown_seconds")] public int CooldownSeconds { get; set; }
        [JsonPropertyName("cooldown_remaining")] public int CooldownRemaining { get; set; }
    }

    internal sealed class SkipData
    {
        [JsonPropertyName("slot")] public int Slot { get; set; }
        [JsonPropertyName("item_id")] public long ItemId { get; set; }
        [JsonPropertyName("reason")] public string Reason { get; set; } = "";
    }
}