/// @name Snake Auto (Campaign) v8
using System;
using System.Linq;
using System.Collections.Generic;

const long HEAD_ID = 769407982;
const int SNAKE_KIND = 5478;
static readonly int[] TARGET_KINDS = { 6559, 3666 };

const int GAME_MIN_X = 20;
const int GAME_MAX_X = 65;
const int GAME_MIN_Y = 20;
const int GAME_MAX_Y = 65;

// Direction -> plate ids (kept from your latest calibration)
const int CTRL_UP = 769406820;
const int CTRL_DOWN = 769407116;
const int CTRL_LEFT = 769407385;
const int CTRL_RIGHT = 769407085;

static readonly string[] DIRS = { "UP", "DOWN", "LEFT", "RIGHT" };

DateTime lastCmd = DateTime.MinValue;
DateTime lastDbg = DateTime.MinValue;
int curDir = -1;
(int x, int y) prevHead = (-1, -1);

bool InBoard(int x, int y)
    => x >= GAME_MIN_X && x <= GAME_MAX_X && y >= GAME_MIN_Y && y <= GAME_MAX_Y;

void Dbg(string m, bool force = false)
{
    if (!force && (DateTime.Now - lastDbg).TotalMilliseconds < 220) return;
    Log($"dbg: {m}");
    lastDbg = DateTime.Now;
}

void Next(int x, int y, int d, out int nx, out int ny)
{
    nx = x + (d == 3 ? 1 : d == 2 ? -1 : 0);
    ny = y + (d == 1 ? 1 : d == 0 ? -1 : 0);
}

int Opp(int d) => d ^ 1;

int DirFromDelta(int dx, int dy)
{
    if (Math.Abs(dx) >= Math.Abs(dy)) return dx < 0 ? 2 : 3;
    return dy < 0 ? 0 : 1;
}

int BtnForDir(int d)
    => d == 0 ? CTRL_UP : d == 1 ? CTRL_DOWN : d == 2 ? CTRL_LEFT : CTRL_RIGHT;

bool TryGetBtnPos(int id, out int x, out int y)
{
    var b = GetFloorItem(id);
    if (b == null) { x = 0; y = 0; return false; }
    x = b.Location.X;
    y = b.Location.Y;
    return true;
}

void Cmd(int d, string reason, (int x, int y) head, (int x, int y)? target)
{
    if ((DateTime.Now - lastCmd).TotalMilliseconds < 120) return;

    int id = BtnForDir(d);
    if (TryGetBtnPos(id, out int bx, out int by)) Move(bx, by);
    Send(Out["ClickFurni"], id, 0);

    lastCmd = DateTime.Now;

    if (target.HasValue)
        Dbg($"{reason} head=({head.x},{head.y}) target=({target.Value.x},{target.Value.y}) dir={DIRS[d]} btn={id}", true);
    else
        Dbg($"{reason} head=({head.x},{head.y}) dir={DIRS[d]} btn={id}", true);
}

bool Bad(int x, int y, HashSet<(int x, int y)> body)
{
    if (!InBoard(x, y)) return true;
    return body.Contains((x, y));
}

int PickDir((int x, int y) head, (int x, int y) target, HashSet<(int x, int y)> body)
{
    var order = new List<int>();

    int dx = target.x - head.x;
    int dy = target.y - head.y;

    if (Math.Abs(dx) >= Math.Abs(dy))
    {
        order.Add(dx < 0 ? 2 : 3);
        order.Add(dy < 0 ? 0 : 1);
    }
    else
    {
        order.Add(dy < 0 ? 0 : 1);
        order.Add(dx < 0 ? 2 : 3);
    }

    order.AddRange(new[] { 0, 1, 2, 3 });

    foreach (int d in order.Distinct())
    {
        if (curDir >= 0 && d == Opp(curDir)) continue;
        Next(head.x, head.y, d, out int nx, out int ny);
        if (!Bad(nx, ny, body)) return d;
    }

    return curDir >= 0 ? curDir : 0;
}

Log("Snake Auto (Campaign) v8 started");
Log($"target kinds: {string.Join(",", TARGET_KINDS)}");
Log($"buttons U={CTRL_UP} D={CTRL_DOWN} L={CTRL_LEFT} R={CTRL_RIGHT}");

while (Run)
{
    Delay(20);

    var headItem = GetFloorItem(HEAD_ID);
    if (headItem == null)
    {
        Dbg("head missing");
        continue;
    }

    var head = (headItem.Location.X, headItem.Location.Y);
    if (!InBoard(head.Item1, head.Item2))
    {
        Dbg($"head out of board ({head.Item1},{head.Item2})");
        continue;
    }

    if (prevHead.x != -1)
    {
        int hdx = head.Item1 - prevHead.x;
        int hdy = head.Item2 - prevHead.y;
        if (hdx != 0 || hdy != 0) curDir = DirFromDelta(hdx, hdy);
    }
    prevHead = head;

    var body = FloorItems
        .Where(i => i != null && i.Kind == SNAKE_KIND)
        .Where(i => InBoard(i.Location.X, i.Location.Y))
        .Select(i => (i.Location.X, i.Location.Y))
        .Where(p => !(p.Item1 == head.Item1 && p.Item2 == head.Item2))
        .ToHashSet();

    var targets = FloorItems
        .Where(i => i != null && TARGET_KINDS.Contains((int)i.Kind))
        .Where(i => InBoard(i.Location.X, i.Location.Y))
        .Select(i => (x: i.Location.X, y: i.Location.Y, kind: (int)i.Kind, id: (long)i.Id))
        .ToList();

    if (targets.Count == 0)
    {
        Dbg("no_target_hold", true);
        continue;
    }

    var target = targets
        .OrderBy(t => Math.Abs(t.x - head.Item1) + Math.Abs(t.y - head.Item2))
        .First();

    int dsel = PickDir(head, (target.x, target.y), body);
    Cmd(dsel, $"seek k={target.kind} id={target.id}", head, (target.x, target.y));
}