using System;
using System.Collections.Generic;
using System.Linq;

// Color Puzzle Solver (fix): solves all 4 rows reliably.
// Keeps desync handling + auto direction flip detection.

const int TILE_KIND = 3696;
const int ARROW_KIND = 17851;
const int GRID_X_MIN = 36;
const int GRID_X_MAX = 39;
const int GRID_Y_MIN = 27;
const int GRID_Y_MAX = 30;
const int CLICK_DELAY_MS = 950;

int GetState(dynamic item)
{
    try { return int.Parse(item.State?.ToString() ?? "0"); }
    catch { return 0; }
}

int GetKind(dynamic item)
{
    try { return (int)item.Kind; }
    catch { return -1; }
}

int[,] ReadGridFromRoom()
{
    int[,] g = new int[4, 4];
    bool[,] found = new bool[4, 4];

    foreach (var item in FloorItems)
    {
        if (item == null) continue;
        if (GetKind(item) != TILE_KIND) continue;

        int x = item.Location.X;
        int y = item.Location.Y;
        double z = item.Location.Z;

        if (x < GRID_X_MIN || x > GRID_X_MAX) continue;
        if (y < GRID_Y_MIN || y > GRID_Y_MAX) continue;
        if (z < 18.4) continue;

        int r = y - GRID_Y_MIN;
        int c = x - GRID_X_MIN;
        g[r, c] = GetState(item);
        found[r, c] = true;
    }

    int cnt = 0;
    for (int r = 0; r < 4; r++)
        for (int c = 0; c < 4; c++)
            if (found[r, c]) cnt++;

    return cnt == 16 ? g : null;
}

string GridDump(int[,] g)
{
    return string.Join(" | ", Enumerable.Range(0, 4).Select(r =>
        $"R{r}[{g[r,0]},{g[r,1]},{g[r,2]},{g[r,3]}]"));
}

void SimMove(int[,] g, int m)
{
    if (m < 4)
    {
        int r = m;
        int t = g[r, 0]; g[r, 0] = g[r, 1]; g[r, 1] = g[r, 2]; g[r, 2] = g[r, 3]; g[r, 3] = t;
    }
    else if (m < 8)
    {
        int r = m - 4;
        int t = g[r, 3]; g[r, 3] = g[r, 2]; g[r, 2] = g[r, 1]; g[r, 1] = g[r, 0]; g[r, 0] = t;
    }
    else if (m < 12)
    {
        int c = m - 8;
        int t = g[0, c]; g[0, c] = g[1, c]; g[1, c] = g[2, c]; g[2, c] = g[3, c]; g[3, c] = t;
    }
    else
    {
        int c = m - 12;
        int t = g[3, c]; g[3, c] = g[2, c]; g[2, c] = g[1, c]; g[1, c] = g[0, c]; g[0, c] = t;
    }
}

List<int> SolveLayerByLayer(int[,] srcGrid, int[] tgtRows)
{
    int[,] g = new int[4, 4];
    for (int r = 0; r < 4; r++)
        for (int c = 0; c < 4; c++)
            g[r, c] = srcGrid[r, c];

    var moves = new List<int>();

    void Do(int m) { moves.Add(m); SimMove(g, m); }

    void DoRowRight(int r, int times)
    {
        times = ((times % 4) + 4) % 4;
        if (times == 3) { Do(r); return; }
        for (int i = 0; i < times; i++) Do(r + 4);
    }
    void DoRowLeft(int r, int times)
    {
        times = ((times % 4) + 4) % 4;
        if (times == 3) { Do(r + 4); return; }
        for (int i = 0; i < times; i++) Do(r);
    }
    void DoColUp(int c, int times)
    {
        times = ((times % 4) + 4) % 4;
        if (times == 3) { Do(c + 12); return; }
        for (int i = 0; i < times; i++) Do(c + 8);
    }
    void DoColDown(int c, int times)
    {
        times = ((times % 4) + 4) % 4;
        if (times == 3) { Do(c + 8); return; }
        for (int i = 0; i < times; i++) Do(c + 12);
    }

    int C0 = tgtRows[0];
    for (int c = 0; c < 4; c++)
    {
        if (g[0, c] == C0) continue;

        int foundRow = -1;
        for (int r = 1; r <= 3; r++)
            if (g[r, c] == C0) { foundRow = r; break; }

        if (foundRow >= 0)
        {
            DoColUp(c, foundRow);
        }
        else
        {
            bool found = false;
            for (int r = 1; r <= 3 && !found; r++)
                for (int c2 = 0; c2 < 4 && !found; c2++)
                    if (c2 != c && g[r, c2] == C0)
                    {
                        DoRowRight(r, (c - c2 + 4) % 4);
                        DoColUp(c, r);
                        found = true;
                    }
            if (!found) return null;
        }
    }

    int C1 = tgtRows[1];
    for (int pass = 0; pass < 8; pass++)
    {
        int colW = -1;
        for (int c = 0; c < 4; c++) if (g[1, c] != C1) { colW = c; break; }
        if (colW < 0) break;

        int srcR = -1, srcC = -1;
        for (int r = 2; r <= 3 && srcR < 0; r++)
            for (int c = 0; c < 4; c++)
                if (g[r, c] == C1) { srcR = r; srcC = c; break; }
        if (srcR < 0) return null;

        if (srcC != colW) DoRowRight(srcR, (colW - srcC + 4) % 4);

        int k2 = srcR - 1;
        DoRowLeft(1, 1);
        DoColUp(colW, k2);
        DoRowRight(1, 1);
        DoColDown(colW, k2);
    }

    int C2 = tgtRows[2];
    for (int pass = 0; pass < 8; pass++)
    {
        int colW = -1;
        for (int c = 0; c < 4; c++) if (g[2, c] != C2) { colW = c; break; }
        if (colW < 0) break;

        int srcC = -1;
        for (int c = 0; c < 4; c++) if (g[3, c] == C2) { srcC = c; break; }
        if (srcC < 0) return null;

        if (srcC != colW) DoRowRight(3, (colW - srcC + 4) % 4);

        DoRowLeft(2, 1);
        DoColUp(colW, 1);
        DoRowRight(2, 1);
        DoColDown(colW, 1);
    }

    for (int r = 0; r < 4; r++)
        for (int c = 0; c < 4; c++)
            if (g[r, c] != tgtRows[r]) return null;

    bool changed = true;
    while (changed)
    {
        changed = false;
        for (int i = 0; i < moves.Count - 1; i++)
        {
            int a = moves[i], b = moves[i + 1];
            bool cancel = false;
            if (a < 4 && b == a + 4) cancel = true;
            if (a >= 4 && a < 8 && b == a - 4) cancel = true;
            if (a >= 8 && a < 12 && b == a + 4) cancel = true;
            if (a >= 12 && b == a - 4) cancel = true;
            if (cancel)
            {
                moves.RemoveAt(i + 1);
                moves.RemoveAt(i);
                changed = true;
                break;
            }
        }
    }

    return moves;
}

bool IsSolvedForTarget(int[,] g, int[] targetRows)
{
    for (int r = 0; r < 4; r++)
        for (int c = 0; c < 4; c++)
            if (g[r, c] != targetRows[r]) return false;
    return true;
}

bool TryReadTargetRows(out int[] targetRows)
{
    targetRows = null;

    var byX = new Dictionary<int, (int[] states, bool[] found, int count)>();

    foreach (var item in FloorItems)
    {
        if (item == null) continue;
        if (GetKind(item) != TILE_KIND) continue;

        int x = item.Location.X;
        int y = item.Location.Y;
        if (y < GRID_Y_MIN || y > GRID_Y_MAX) continue;
        if (x >= GRID_X_MIN && x <= GRID_X_MAX) continue;

        if (!byX.ContainsKey(x))
            byX[x] = (new int[4], new bool[4], 0);

        var entry = byX[x];
        int r = y - GRID_Y_MIN;
        if (!entry.found[r])
        {
            entry.states[r] = GetState(item);
            entry.found[r] = true;
            entry.count++;
            byX[x] = entry;
        }
    }

    if (byX.Count == 0) return false;

    var best = byX
        .Select(kvp => new
        {
            X = kvp.Key,
            States = kvp.Value.states,
            Count = kvp.Value.count,
            Dist = kvp.Key < GRID_X_MIN ? (GRID_X_MIN - kvp.Key) : (kvp.Key - GRID_X_MAX)
        })
        .OrderByDescending(x => x.Count)
        .ThenBy(x => x.Dist)
        .First();

    if (best.Count < 4) return false;

    targetRows = new int[4];
    for (int r = 0; r < 4; r++) targetRows[r] = best.States[r];
    return true;
}

uint EncodeGrid(int[,] g)
{
    uint s = 0;
    for (int r = 0; r < 4; r++)
        for (int c = 0; c < 4; c++)
            s |= ((uint)(g[r, c] & 3)) << (2 * (r * 4 + c));
    return s;
}

uint ApplyMoveBits(uint s, int m)
{
    if (m < 4)
    {
        int sh = m * 8;
        uint row = (s >> sh) & 0xFFu;
        uint rot = ((row >> 2) | (row << 6)) & 0xFFu;
        return (s & ~(0xFFu << sh)) | (rot << sh);
    }
    if (m < 8)
    {
        int sh = (m - 4) * 8;
        uint row = (s >> sh) & 0xFFu;
        uint rot = ((row << 2) | (row >> 6)) & 0xFFu;
        return (s & ~(0xFFu << sh)) | (rot << sh);
    }
    if (m < 12)
    {
        int b = (m - 8) * 2;
        uint v0 = (s >> b) & 3u, v1 = (s >> (b + 8)) & 3u, v2 = (s >> (b + 16)) & 3u, v3 = (s >> (b + 24)) & 3u;
        uint mask = ~(3u << b | 3u << (b + 8) | 3u << (b + 16) | 3u << (b + 24));
        return (s & mask) | (v1 << b) | (v2 << (b + 8)) | (v3 << (b + 16)) | (v0 << (b + 24));
    }
    {
        int b = (m - 12) * 2;
        uint v0 = (s >> b) & 3u, v1 = (s >> (b + 8)) & 3u, v2 = (s >> (b + 16)) & 3u, v3 = (s >> (b + 24)) & 3u;
        uint mask = ~(3u << b | 3u << (b + 8) | 3u << (b + 16) | 3u << (b + 24));
        return (s & mask) | (v3 << b) | (v0 << (b + 8)) | (v1 << (b + 16)) | (v2 << (b + 24));
    }
}

int InverseMove(int m)
{
    if (m < 4) return m + 4;
    if (m < 8) return m - 4;
    if (m < 12) return m + 4;
    return m - 4;
}

string MoveName(int m)
{
    if (m < 4) return $"Row{m} LEFT";
    if (m < 8) return $"Row{m - 4} RIGHT";
    if (m < 12) return $"Col{m - 8} UP";
    return $"Col{m - 12} DOWN";
}

int[,] ApplyMovesToCopy(int[,] src, List<int> moves)
{
    int[,] g = new int[4, 4];
    for (int r = 0; r < 4; r++)
        for (int c = 0; c < 4; c++)
            g[r, c] = src[r, c];
    foreach (int m in moves) SimMove(g, m);
    return g;
}

Log("=== Color Puzzle Solver (fix all rows) ===");

var grid = ReadGridFromRoom();
if (grid == null)
{
    Log("ERROR: Could not read full 4x4 grid.");
    return;
}
Log($"Start: {GridDump(grid)}");

var arrowIds = new Dictionary<string, long>();
foreach (var item in FloorItems)
{
    if (item == null) continue;
    if (GetKind(item) != ARROW_KIND) continue;

    int x = item.Location.X, y = item.Location.Y;
    if (y == GRID_Y_MIN - 1 && x >= GRID_X_MIN && x <= GRID_X_MAX)
        arrowIds[$"up_{x - GRID_X_MIN}"] = item.Id;
    else if (y == GRID_Y_MAX + 1 && x >= GRID_X_MIN && x <= GRID_X_MAX)
        arrowIds[$"down_{x - GRID_X_MIN}"] = item.Id;
    else if (x == GRID_X_MIN - 1 && y >= GRID_Y_MIN && y <= GRID_Y_MAX)
        arrowIds[$"left_{y - GRID_Y_MIN}"] = item.Id;
    else if (x == GRID_X_MAX + 1 && y >= GRID_Y_MIN && y <= GRID_Y_MAX)
        arrowIds[$"right_{y - GRID_Y_MIN}"] = item.Id;
}

if (arrowIds.Count < 16)
{
    Log($"ERROR: Missing arrows ({arrowIds.Count}/16).");
    return;
}

int[] detectedTarget;
if (!TryReadTargetRows(out detectedTarget))
{
    detectedTarget = new[] { 1, 2, 3, 0 };
    Log("WARN: Target tiles not fully detected, using fallback target rows 1,2,3,0.");
}

var candidateTargets = new List<int[]>();
void AddTargetCandidate(int[] t)
{
    if (t == null || t.Length != 4) return;
    if (!candidateTargets.Any(x => x[0] == t[0] && x[1] == t[1] && x[2] == t[2] && x[3] == t[3]))
        candidateTargets.Add(new[] { t[0], t[1], t[2], t[3] });
}

AddTargetCandidate(detectedTarget);
AddTargetCandidate(new[] { detectedTarget[3], detectedTarget[2], detectedTarget[1], detectedTarget[0] });
AddTargetCandidate(new[] { 1, 2, 3, 0 });
AddTargetCandidate(new[] { 0, 3, 2, 1 });

List<int> solution = null;
int[] targetRows = null;

foreach (var candidate in candidateTargets)
{
    var s = SolveLayerByLayer(grid, candidate);
    if (s == null || s.Count == 0) continue;

    var check = ApplyMovesToCopy(grid, s);
    if (!IsSolvedForTarget(check, candidate)) continue;

    if (solution == null || s.Count < solution.Count)
    {
        solution = s;
        targetRows = candidate;
    }
}

if (solution == null || targetRows == null)
{
    Log("ERROR: Could not build a valid full 4-row plan.");
    return;
}

Log($"Target rows chosen: R0={targetRows[0]}, R1={targetRows[1]}, R2={targetRows[2]}, R3={targetRows[3]}");
Log($"Plan length: {solution.Count} moves");

bool[] rowFlip = new bool[4];
bool[] colFlip = new bool[4];

string KeyForMove(int m)
{
    if (m < 4) { int r = m; return rowFlip[r] ? $"right_{r}" : $"left_{r}"; }
    if (m < 8) { int r = m - 4; return rowFlip[r] ? $"left_{r}" : $"right_{r}"; }
    if (m < 12) { int c = m - 8; return colFlip[c] ? $"down_{c}" : $"up_{c}"; }
    int cc = m - 12; return colFlip[cc] ? $"up_{cc}" : $"down_{cc}";
}

int[,] tgtGrid = new int[4, 4];
for (int r = 0; r < 4; r++)
    for (int c = 0; c < 4; c++)
        tgtGrid[r, c] = targetRows[r];

uint goalState = EncodeGrid(tgtGrid);
uint currentState = EncodeGrid(grid);

int moveIdx = 0;
int retries = 0;
const int MAX_RETRIES = 3;

while (moveIdx < solution.Count)
{
    if (currentState == goalState)
    {
        Log("=== Solved: all 4 rows complete ===");
        return;
    }

    int move = solution[moveIdx];
    uint expected = ApplyMoveBits(currentState, move);
    string key = KeyForMove(move);

    if (!arrowIds.ContainsKey(key))
    {
        Log($"ERROR: Arrow '{key}' not found.");
        return;
    }

    long id = arrowIds[key];
    Log($"[{moveIdx + 1}/{solution.Count}] {MoveName(move)} via {key}");
    Send(Out["ClickFurni"], (int)id, 0);
    Delay(CLICK_DELAY_MS);

    var newGrid = ReadGridFromRoom();
    if (newGrid == null)
    {
        Log("WARN: Grid read failed, retry...");
        Delay(400);
        continue;
    }

    uint afterState = EncodeGrid(newGrid);

    if (afterState == expected)
    {
        currentState = afterState;
        moveIdx++;
        retries = 0;
        continue;
    }

    uint invExpected = ApplyMoveBits(currentState, InverseMove(move));
    if (afterState == invExpected)
    {
        if (move < 8)
        {
            int r = move < 4 ? move : move - 4;
            rowFlip[r] = !rowFlip[r];
            Log($"Auto-fix: Row {r} direction flipped.");
        }
        else
        {
            int c = move < 12 ? move - 8 : move - 12;
            colFlip[c] = !colFlip[c];
            Log($"Auto-fix: Col {c} direction flipped.");
        }

        grid = newGrid;
        currentState = afterState;

        var replan = SolveLayerByLayer(grid, targetRows);
        if (replan == null)
        {
            Log("ERROR: Replan failed after direction flip.");
            return;
        }

        solution = replan;
        moveIdx = 0;
        retries = 0;
        Log($"Replan: {solution.Count} moves");
        continue;
    }

    if (afterState == currentState)
    {
        retries++;
        if (retries >= MAX_RETRIES)
        {
            Log("WARN: Click had no effect multiple times, replan.");
            grid = newGrid;
            var replan = SolveLayerByLayer(grid, targetRows);
            if (replan == null)
            {
                Log("ERROR: Replan failed after no-effect clicks.");
                return;
            }
            solution = replan;
            moveIdx = 0;
            retries = 0;
        }
        else
        {
            Log("Click no effect, retrying...");
            Delay(300);
        }
        continue;
    }

    Log($"Desync detected. New grid: {GridDump(newGrid)}");
    grid = newGrid;
    currentState = afterState;

    if (IsSolvedForTarget(grid, targetRows))
    {
        Log("=== Solved: all 4 rows complete ===");
        return;
    }

    var desyncReplan = SolveLayerByLayer(grid, targetRows);
    if (desyncReplan == null)
    {
        Log("ERROR: Replan failed after desync.");
        return;
    }

    solution = desyncReplan;
    moveIdx = 0;
    retries = 0;
    Log($"Replan after desync: {solution.Count} moves");
}

if (currentState == goalState)
    Log("=== Solved: all 4 rows complete ===");
else
    Log("Moves done. Please check if room state changed externally.");