using System.Diagnostics;
using Poe2Trade.Core;
using Poe2Trade.Game;
using Poe2Trade.Inventory;
using Poe2Trade.Screen;
using Serilog;

namespace Poe2Trade.Bot;

/// <summary>
/// Base class for game executors that interact with the game world.
/// Provides shared utilities: loot pickup, recovery, walking, stash tab resolution.
/// </summary>
public abstract class GameExecutor
{
    protected static readonly Random Rng = new();

    protected readonly IGameController _game;
    protected readonly IScreenReader _screen;
    protected readonly IInventoryManager _inventory;
    protected readonly SavedSettings _config;
    protected volatile bool _stopped;
    protected CancellationTokenSource _stopCts = new();

    /// <summary>Cancellation token that fires when Stop() is called.</summary>
    protected CancellationToken StopToken => _stopCts.Token;

    protected GameExecutor(IGameController game, IScreenReader screen,
        IInventoryManager inventory, SavedSettings config)
    {
        _game = game;
        _screen = screen;
        _inventory = inventory;
        _config = config;
    }

    public virtual void Stop()
    {
        _stopped = true;
        _stopCts.Cancel();
    }

    /// <summary>Reset stopped state for a new run.</summary>
    protected void ResetStop()
    {
        _stopped = false;
        _stopCts.Dispose();
        _stopCts = new CancellationTokenSource();
    }

    /// <summary>Cancellable sleep that throws OperationCanceledException when stopped.</summary>
    protected Task Sleep(int ms) => Helpers.Sleep(ms, _stopCts.Token);

    // ------ Loot pickup ------

    // Tiers to skip (noise, low-value, or hidden by filter)
    private static readonly HashSet<string> SkipTiers = ["gold"];

    public async Task Loot()
    {
        Log.Information("Starting loot pickup");

        const int maxRounds = 5;
        var totalPicked = 0;

        for (var round = 0; round < maxRounds; round++)
        {
            if (_stopped) return;

            // Move mouse out of the way so it doesn't cover labels
            _game.MoveMouseInstant(0, 1440);
            await Sleep(100);

            // Hold Alt, capture, detect
            await _game.KeyDown(InputSender.VK.MENU);
            await Sleep(250);

            using var capture = _screen.CaptureRawBitmap();
            var labels = _screen.DetectLootLabels(capture, capture);
            var pickups = labels.Where(l => !SkipTiers.Contains(l.Tier)).ToList();

            if (pickups.Count == 0)
            {
                await _game.KeyUp(InputSender.VK.MENU);
                Log.Information("No loot labels in round {Round} (picked {Total} total)", round + 1, totalPicked);
                break;
            }

            Log.Information("Round {Round}: {Count} loot labels ({Skipped} skipped)",
                round + 1, pickups.Count, labels.Count - pickups.Count);

            // Click all detected labels (positions are stable)
            foreach (var label in pickups)
            {
                if (_stopped) break;
                Log.Information("Picking up: tier={Tier} color=({R},{G},{B}) at ({X},{Y})",
                    label.Tier, label.AvgR, label.AvgG, label.AvgB, label.CenterX, label.CenterY);
                await _game.LeftClickAt(label.CenterX, label.CenterY);
                totalPicked++;
                await Sleep(200);
            }

            // Quick check: capture small region around each clicked label to see if
            // new labels appeared underneath. If none changed, we're done.
            await Sleep(300);
            _game.MoveMouseInstant(0, 1440);
            await Sleep(100);

            using var recheck = _screen.CaptureRawBitmap();
            var newLabels = _screen.DetectLootLabels(recheck, recheck);
            var newPickups = newLabels.Where(l => !SkipTiers.Contains(l.Tier)).ToList();

            await _game.KeyUp(InputSender.VK.MENU);

            if (newPickups.Count == 0)
            {
                Log.Information("Quick recheck: no new labels, done (picked {Total} total)", totalPicked);
                break;
            }

            Log.Information("Quick recheck: {Count} new labels appeared, continuing", newPickups.Count);
            await Sleep(300);
        }

        Log.Information("Loot pickup complete ({Count} items)", totalPicked);
    }

    // ------ Recovery ------

    protected async Task RecoverToHideout()
    {
        try
        {
            Log.Information("Recovering: escaping and going to hideout");
            await _game.FocusGame();
            // await _game.PressEscape();
            // await Sleep(Delays.PostEscape);
            // await _game.PressEscape();
            // await Sleep(Delays.PostEscape);

            var arrived = await _inventory.WaitForAreaTransition(
                _config.TravelTimeoutMs, () => _game.GoToHideout());
            if (arrived)
            {
                _inventory.SetLocation(true);
                Log.Information("Recovery: arrived at hideout");
            }
            else
            {
                Log.Warning("Recovery: timed out going to hideout");
            }
        }
        catch (Exception ex)
        {
            Log.Error(ex, "Recovery failed");
        }
    }

    // ------ Walk + template match ------

    protected async Task<TemplateMatchResult?> WalkAndMatch(string templatePath, int vk1, int vk2,
        int timeoutMs = 15000, int closeRadius = 350)
    {
        const int screenCx = 2560 / 2;
        const int screenCy = 1440 / 2;

        await _game.KeyDown(vk1);
        await _game.KeyDown(vk2);
        try
        {
            var sw = Stopwatch.StartNew();
            bool spotted = false;
            while (sw.ElapsedMilliseconds < timeoutMs)
            {
                if (_stopped) return null;
                var match = await _screen.TemplateMatch(templatePath);
                if (match == null)
                {
                    await Sleep(500);
                    continue;
                }

                var dx = match.X - screenCx;
                var dy = match.Y - screenCy;
                var dist = Math.Sqrt(dx * dx + dy * dy);

                if (!spotted)
                {
                    Log.Information("Template spotted at ({X},{Y}), dist={Dist:F0}px from center, approaching...",
                        match.X, match.Y, dist);
                    spotted = true;
                }

                if (dist <= closeRadius)
                {
                    Log.Information("Close enough at ({X},{Y}), dist={Dist:F0}px, stopping", match.X, match.Y, dist);

                    // Stop, settle, re-match for accurate position
                    await _game.KeyUp(vk2);
                    await _game.KeyUp(vk1);
                    await Sleep(300);

                    var fresh = await _screen.TemplateMatch(templatePath);
                    if (fresh != null)
                    {
                        Log.Information("Final position at ({X},{Y})", fresh.X, fresh.Y);
                        return fresh;
                    }
                    Log.Warning("Re-match failed, using last known position");
                    return match;
                }

                await Sleep(200);
            }
            Log.Error("WalkAndMatch timed out after {Ms}ms (spotted={Spotted})", timeoutMs, spotted);
            return null;
        }
        finally
        {
            await _game.KeyUp(vk2);
            await _game.KeyUp(vk1);
        }
    }

    // ------ Stash tab resolution ------

    protected (StashTabInfo? Tab, StashTabInfo? Folder) ResolveTabPath(string tabPath)
    {
        if (string.IsNullOrEmpty(tabPath) || _config.StashCalibration == null)
            return (null, null);

        var parts = tabPath.Split('/');
        if (parts.Length == 1)
        {
            var tab = _config.StashCalibration.Tabs.FirstOrDefault(t => t.Name == parts[0]);
            return (tab, null);
        }

        if (parts.Length == 2)
        {
            var folder = _config.StashCalibration.Tabs.FirstOrDefault(t => t.Name == parts[0] && t.IsFolder);
            if (folder == null) return (null, null);
            var subTab = folder.SubTabs.FirstOrDefault(t => t.Name == parts[1]);
            return (subTab, folder);
        }

        return (null, null);
    }
}