using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using System.Runtime.InteropServices;
using Serilog;
using PCMonitor;

namespace PCMonitorAgent.Services
{
    /// <summary>
    /// Monitor Aktivitas PC (Aplikasi, Browser, File Access)
    /// </summary>
    public class ActivityMonitor : IDisposable
    {
        private readonly ApiClient apiClient;
        private readonly ILogger logger;
        private DateTime lastBrowserCheck = DateTime.Now.AddHours(-1);

        public ActivityMonitor(ApiClient client)
        {
            apiClient = client;
            logger = Log.ForContext<ActivityMonitor>();
        }

        /// <summary>
        /// Collect activities dari PC
        /// </summary>
        public async Task CollectAsync()
        {
            try
            {
                // 1. Monitor browser history
                var browserActivities = GetBrowserHistory();
                foreach (var activity in browserActivities)
                {
                    try
                    {
                        await apiClient.SendActivityAsync(activity);
                    }
                    catch (Exception ex)
                    {
                        logger.Warning("Failed to send browser activity: {Message}", ex.Message);
                    }
                }

                // 2. Monitor running applications
                var appActivities = GetRunningApplications();
                foreach (var activity in appActivities)
                {
                    try
                    {
                        await apiClient.SendActivityAsync(activity);
                    }
                    catch (Exception ex)
                    {
                        logger.Warning("Failed to send app activity: {Message}", ex.Message);
                    }
                }

                lastBrowserCheck = DateTime.Now;
                logger.Debug("Activities collected successfully");
            }
            catch (Exception ex)
            {
                logger.Error(ex, "Error collecting activities");
            }
        }

        /// <summary>
        /// Ambil browser history dari Chrome, Edge, Firefox
        /// </summary>
        private List<dynamic> GetBrowserHistory()
        {
            var history = new List<dynamic>();

            try
            {
                // Chrome history
                history.AddRange(GetChromeHistory());

                // Edge history
                history.AddRange(GetEdgeHistory());

                // Firefox history
                history.AddRange(GetFirefoxHistory());
            }
            catch (Exception ex)
            {
                logger.Warning(ex, "Error getting browser history");
            }

            return history;
        }

        /// <summary>
        /// Get Chrome history
        /// </summary>
        private List<dynamic> GetChromeHistory()
        {
            var history = new List<dynamic>();

            try
            {
                string chromePath = Path.Combine(
                    Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
                    "Google\\Chrome\\User Data\\Default\\History");

                if (File.Exists(chromePath))
                {
                    // Chrome history database (SQLite)
                    var chromeHistory = ReadSQLiteDatabase(chromePath, "urls");
                    foreach (var entry in chromeHistory)
                    {
                        history.Add(new
                        {
                            activity_type = "browser_open",
                            browser_name = "Chrome",
                            website_url = entry["url"],
                            website_title = entry["title"],
                            logged_at = DateTime.Now
                        });
                    }
                }
            }
            catch (Exception ex)
            {
                logger.Warning(ex, "Error reading Chrome history");
            }

            return history;
        }

        /// <summary>
        /// Get Edge history
        /// </summary>
        private List<dynamic> GetEdgeHistory()
        {
            var history = new List<dynamic>();

            try
            {
                string edgePath = Path.Combine(
                    Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
                    "Microsoft\\Edge\\User Data\\Default\\History");

                if (File.Exists(edgePath))
                {
                    var edgeHistory = ReadSQLiteDatabase(edgePath, "urls");
                    foreach (var entry in edgeHistory)
                    {
                        history.Add(new
                        {
                            activity_type = "browser_open",
                            browser_name = "Edge",
                            website_url = entry["url"],
                            website_title = entry["title"],
                            logged_at = DateTime.Now
                        });
                    }
                }
            }
            catch (Exception ex)
            {
                logger.Warning(ex, "Error reading Edge history");
            }

            return history;
        }

        /// <summary>
        /// Get Firefox history
        /// </summary>
        private List<dynamic> GetFirefoxHistory()
        {
            var history = new List<dynamic>();

            try
            {
                string firefoxPath = Path.Combine(
                    Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
                    "Mozilla\\Firefox\\Profiles");

                if (Directory.Exists(firefoxPath))
                {
                    var profiles = Directory.GetDirectories(firefoxPath);
                    foreach (var profile in profiles)
                    {
                        string dbPath = Path.Combine(profile, "places.sqlite");
                        if (File.Exists(dbPath))
                        {
                            var ffHistory = ReadSQLiteDatabase(dbPath, "moz_places");
                            foreach (var entry in ffHistory)
                            {
                                history.Add(new
                                {
                                    activity_type = "browser_open",
                                    browser_name = "Firefox",
                                    website_url = entry["url"],
                                    website_title = entry["title"],
                                    logged_at = DateTime.Now
                                });
                            }
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                logger.Warning(ex, "Error reading Firefox history");
            }

            return history;
        }

        /// <summary>
        /// Helper untuk membaca SQLite database
        /// </summary>
        private List<Dictionary<string, object>> ReadSQLiteDatabase(string dbPath, string table)
        {
            var result = new List<Dictionary<string, object>>();
            // Implementation akan menggunakan System.Data.SQLite jika diperlukan
            // Untuk sekarang, return empty list
            return result;
        }

        /// <summary>
        /// Get running applications
        /// </summary>
        private List<dynamic> GetRunningApplications()
        {
            var apps = new List<dynamic>();

            try
            {
                var processes = Process.GetProcesses();
                foreach (var process in processes)
                {
                    try
                    {
                        if (!string.IsNullOrEmpty(process.MainWindowTitle) && process.MainWindowTitle.Length > 0)
                        {
                            apps.Add(new
                            {
                                activity_type = "app_launch",
                                app_name = process.ProcessName,
                                app_path = GetProcessPath(process),
                                description = process.MainWindowTitle,
                                logged_at = DateTime.Now
                            });
                        }
                    }
                    catch { }
                }
            }
            catch (Exception ex)
            {
                logger.Warning(ex, "Error getting running applications");
            }

            return apps;
        }

        /// <summary>
        /// Get process executable path
        /// </summary>
        private string GetProcessPath(Process process)
        {
            try
            {
                return process.MainModule?.FileName ?? "";
            }
            catch
            {
                return "";
            }
        }

        public void Dispose()
        {
            // Cleanup if needed
        }
    }

    /// <summary>
    /// Browser History Helper
    /// </summary>
    public class BrowserHistoryHelper
    {
        public List<dynamic> GetChromeHistory() {
            var history = new List<dynamic>();
            try {
                string chromePath = Path.Combine(
                    Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
                    @"Google\Chrome\User Data\Default\History"
                );
                
                if (File.Exists(chromePath)) {
                    // Note: This is simplified. Real implementation would need to access Chrome's SQLite database
                    history.Add(new {
                        activity_type = "browser_open",
                        browser_name = "Chrome",
                        website_url = "http://example.com",
                        website_title = "Chrome Activity",
                        visit_time = DateTime.Now
                    });
                }
            } catch { }
            return history;
        }

        private List<dynamic> GetEdgeHistory() {
            var history = new List<dynamic>();
            // Similar to Chrome
            return history;
        }

        private List<dynamic> GetFirefoxHistory() {
            var history = new List<dynamic>();
            // Similar to Chrome
            return history;
        }

        public void Dispose() { }
    }

    /// <summary>
    /// Windows Event Hook untuk mendeteksi aktivitas window
    /// </summary>
    public class WinEventHook : IDisposable {
        private const int EVENT_SYSTEM_FOREGROUND = 3;
        private IntPtr hookHandle = IntPtr.Zero;
        private delegate void WinEventDelegate(IntPtr hWinEventHook, uint eventType, IntPtr hwnd, int idObject, int idChild, uint dwEventThread, uint dwmsEventTime);

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        private static extern IntPtr SetWinEventHook(uint eventMin, uint eventMax, IntPtr hmodWinEventHook, WinEventDelegate lpfnWinEventHook, uint idProcess, uint idThread, uint dwFlags);

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        private static extern bool UnhookWinEvent(IntPtr hWinEventHook);

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        private static extern int GetWindowText(IntPtr hWnd, System.Text.StringBuilder text, int count);

        public void Dispose() {
            if (hookHandle != IntPtr.Zero) {
                UnhookWinEvent(hookHandle);
                hookHandle = IntPtr.Zero;
            }
        }
    }
}