using System.Net.Http.Headers;
using System.Net.Http.Json;
using System.Text.Json;
using System.Text.Json.Nodes;
using Nexus.Api.Models;

namespace Nexus.Api.Services;

public sealed class OpenClawGatewayClient(HttpClient httpClient, IConfiguration configuration)
{
    private static readonly JsonSerializerOptions JsonOptions = new()
    {
        PropertyNameCaseInsensitive = true,
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase
    };

    private string? GetPassword()
    {
        var password = configuration["Integrations:OpenClaw:Password"];
        if (string.IsNullOrWhiteSpace(password))
            password = configuration["Integrations:OpenClaw:Token"];
        return string.IsNullOrWhiteSpace(password) ? null : password;
    }

    private void ApplyAuth(HttpRequestMessage request)
    {
        var password = GetPassword();
        if (password is not null)
            request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", password);
    }

    public async Task<JsonNode?> InvokeToolAsync(string tool, object? args = null)
    {
        try
        {
            using var request = new HttpRequestMessage(HttpMethod.Post, "/tools/invoke");
            ApplyAuth(request);

            var body = new Dictionary<string, object?> { ["tool"] = tool };
            if (args is not null)
                body["args"] = args;

            request.Content = JsonContent.Create(body);

            using var response = await httpClient.SendAsync(request);
            if (!response.IsSuccessStatusCode)
                return null;

            var json = await response.Content.ReadAsStringAsync();
            if (string.IsNullOrWhiteSpace(json))
                return null;

            return JsonNode.Parse(json);
        }
        catch
        {
            return null;
        }
    }

    public async Task<List<DashboardAgentInfo>> GetAgentsAsync()
    {
        var agents = new List<DashboardAgentInfo>();

        // Get sessions list (active agents/sessions)
        var sessionsResult = await InvokeToolAsync("sessions_list");
        if (sessionsResult is not null)
        {
            var sessions = sessionsResult.AsArray();
            if (sessions is not null)
            {
                foreach (var session in sessions)
                {
                    if (session is null) continue;
                    var id = session["sessionKey"]?.GetValue<string>() ?? session["id"]?.GetValue<string>() ?? "";
                    var name = session["name"]?.GetValue<string>() ?? id;
                    var model = session["model"]?.GetValue<string>() ?? "";
                    var status = session["status"]?.GetValue<string>() ?? "";
                    var isActive = status.Equals("active", StringComparison.OrdinalIgnoreCase);

                    agents.Add(new DashboardAgentInfo(
                        Id: id,
                        Name: name,
                        Role: DeriveRole(id),
                        Model: model,
                        IsActive: isActive,
                        CurrentTask: session["currentTask"]?.GetValue<string>()
                    ));
                }
            }
        }

        // Also get subagents list
        var subagentsResult = await InvokeToolAsync("sub_agents_list");
        if (subagentsResult is not null && subagentsResult is JsonArray subArray)
        {
            foreach (var sub in subArray)
            {
                if (sub is null) continue;
                var id = sub["id"]?.GetValue<string>() ?? "";
                if (agents.Any(a => a.Id == id)) continue;

                var name = sub["name"]?.GetValue<string>() ?? id;
                var model = sub["model"]?.GetValue<string>() ?? "";
                var status = sub["status"]?.GetValue<string>() ?? "";
                var isActive = status.Equals("active", StringComparison.OrdinalIgnoreCase) ||
                               status.Equals("running", StringComparison.OrdinalIgnoreCase);

                agents.Add(new DashboardAgentInfo(
                    Id: id,
                    Name: name,
                    Role: DeriveRole(id),
                    Model: model,
                    IsActive: isActive,
                    CurrentTask: sub["currentTask"]?.GetValue<string>()
                ));
            }
        }

        return agents.Count > 0 ? agents : new List<DashboardAgentInfo>();
    }

    public async Task<List<MessageEntry>> GetSessionHistoryAsync(string sessionKey, int limit = 50, int offset = 0)
    {
        try
        {
            var result = await InvokeToolAsync("sessions_history", new
            {
                sessionKey,
                limit,
                offset
            });

            if (result is null)
                return new List<MessageEntry>();

            var messages = new List<MessageEntry>();
            var array = result as JsonArray ?? result.AsArray();
            if (array is null) return messages;

            foreach (var msg in array)
            {
                if (msg is null) continue;
                var role = msg["role"]?.GetValue<string>() ?? "";
                var content = msg["content"]?.GetValue<string>() ?? "";
                var timestamp = msg["timestamp"]?.GetValue<string>()
                    ?? msg["ts"]?.GetValue<string>()
                    ?? msg["createdAt"]?.GetValue<string>()
                    ?? DateTimeOffset.UtcNow.ToString("o");

                messages.Add(new MessageEntry(role, content, timestamp));
            }

            return messages;
        }
        catch
        {
            return new List<MessageEntry>();
        }
    }

    public async Task<ChatResponse> SendChatMessageAsync(string sessionKey, string message)
    {
        try
        {
            var result = await InvokeToolAsync("sessions_send", new
            {
                sessionKey,
                message
            });

            if (result is null)
                return new ChatResponse(false, null, "Gateway nicht erreichbar");

            var ok = result["ok"]?.GetValue<bool>() ?? result["success"]?.GetValue<bool>() ?? false;
            var reply = result["reply"]?.GetValue<string>()
                ?? result["response"]?.GetValue<string>()
                ?? result["content"]?.GetValue<string>();
            var error = result["error"]?.GetValue<string>();

            return new ChatResponse(ok, reply, error);
        }
        catch (Exception ex)
        {
            return new ChatResponse(false, null, $"Fehler: {ex.Message}");
        }
    }

    public async Task<List<QueueItem>> GetQueueAsync()
    {
        try
        {
            var result = await InvokeToolAsync("cron_list");
            if (result is null)
                return new List<QueueItem>();

            var items = new List<QueueItem>();
            var array = result as JsonArray ?? result.AsArray();
            if (array is null) return items;

            foreach (var entry in array)
            {
                if (entry is null) continue;
                var id = entry["id"]?.GetValue<string>() ?? "";
                var name = entry["name"]?.GetValue<string>() ?? id;
                var status = entry["status"]?.GetValue<string>() ?? "unknown";

                items.Add(new QueueItem(id, name, status));
            }

            return items;
        }
        catch
        {
            return new List<QueueItem>();
        }
    }

    public async Task<DashboardStatus> GetStatusAsync()
    {
        var gatewayOk = false;
        var irisStatus = "Offline";
        var activeAgents = 0;
        var pendingTasks = 0;

        try
        {
            // Check gateway health
            using var pingRequest = new HttpRequestMessage(HttpMethod.Get, "/");
            ApplyAuth(pingRequest);
            using var pingResponse = await httpClient.SendAsync(pingRequest);
            gatewayOk = pingResponse.IsSuccessStatusCode;

            if (gatewayOk)
            {
                // Get session status
                var sessionResult = await InvokeToolAsync("session_status");
                if (sessionResult is not null)
                {
                    irisStatus = sessionResult["status"]?.GetValue<string>() ?? "Active";
                }

                // Get agents for active count
                var agents = await GetAgentsAsync();
                activeAgents = agents.Count(a => a.IsActive);

                // Get queue/cron for pending tasks
                var queue = await GetQueueAsync();
                pendingTasks = queue.Count;
            }
        }
        catch
        {
            gatewayOk = false;
        }

        return new DashboardStatus(gatewayOk, irisStatus, activeAgents, pendingTasks);
    }

    private static string DeriveRole(string agentId) => agentId.ToLowerInvariant() switch
    {
        "iris" => "Orchestrator",
        "programmer" => "Developer",
        "reviewer" => "Reviewer",
        "architekt" => "Architect",
        "main" => "Assistant",
        _ => "Custom"
    };
}