[fix] AI strategy detect win first, killer instinct and button press. Although not 100% okay as button is not always detected during 'thinking"

src/main.cpp

@@ -5,7 +5,6 @@
 #include <WebServer.h>
 #include <Preferences.h>
 
-// Build Flag Default (can be overridden in platformio.ini)
 #ifndef SHOW_BORDER
 #define SHOW_BORDER 1
 #endif
@@ -14,7 +13,6 @@
 const int COLS = 7;
 const int ROWS = 6;
 
-// --- Configuration & Globals ---
 CRGB leds[NUM_LEDS];
 Encoder myEnc(ENC_A, ENC_B);
 WebServer server(80);
@@ -41,6 +39,7 @@ uint32_t lastActivityTime = 0;
 uint32_t demoResetTimer = 0;
 bool isDemoOver = false;
 uint8_t demoPly = 4;
+bool abortAi = false;
 
 uint8_t current_look_ahead;
 uint8_t current_brightness;
@@ -66,8 +65,6 @@ void performAiMove(int8_t aiPlayer);
 void showMenu();
 int getDynamicPly();
 
-// --- Utility & Rendering ---
-
 int getIdx(int x, int y) { return (y * 8) + x; }
 
 void drawStaticUI()
@@ -112,6 +109,16 @@ int getFirstEmptyRow(int col)
     return -1;
 }
 
+bool isBoardFull()
+{
+    for (int column = 0; column < COLS; column++)
+    {
+        if (board[column][ROWS - 1] == 0)
+            return false;
+    }
+    return true;
+}
+
 int getDynamicPly()
 {
     if (!progressive_difficulty && gameState != DEMO)
@@ -124,8 +131,6 @@ int getDynamicPly()
     return constrain(current_look_ahead + (occupiedCount / 7), 1, 10);
 }
 
-// --- Visuals & Animations ---
-
 void updateThinkingVisuals(int8_t playerColor, int8_t column)
 {
     static uint32_t lastCycle = 0;
@@ -172,7 +177,7 @@ void moveDiscToCol(int startCol, int targetCol, int player, int speed)
 {
     int current = startCol;
     CRGB pColor = (player == 1) ? CRGB::Yellow : CRGB::Red;
-    while (current != targetCol)
+    while (current != targetCol && !abortAi)
     {
         leds[getIdx(current, 0)] = CRGB::Black;
         current += (targetCol > current) ? 1 : -1;
@@ -180,89 +185,90 @@ void moveDiscToCol(int startCol, int targetCol, int player, int speed)
         leds[getIdx(current, 0)] = pColor;
         FastLED.show();
         delay(speed);
+        if (digitalRead(ENC_SW) == LOW)
+            abortAi = true;
     }
     activeCol = targetCol;
 }
 
-// --- AI Engine ---
-
-bool isBoardFull()
-{
-    for (int column = 0; column < COLS; column++)
-        if (board[column][5] == 0)
-            return false;
-    return true;
-}
-
 int8_t scanBoard()
 {
     memset(winMask, 0, sizeof(winMask));
     auto checkMatch = [&](int col, int row, int dCol, int dRow)
     {
-        int8_t playerAtPos = board[col][row];
+        int8_t pAtPos = board[col][row];
-        if (playerAtPos != 0 &&
+        if (pAtPos != 0 && board[col + dCol][row + dRow] == pAtPos &&
-            board[col + dCol][row + dRow] == playerAtPos &&
+            board[col + 2 * dCol][row + 2 * dRow] == pAtPos && board[col + 3 * dCol][row + 3 * dRow] == pAtPos)
-            board[col + 2 * dCol][row + 2 * dRow] == playerAtPos &&
-            board[col + 3 * dCol][row + 3 * dRow] == playerAtPos)
         {
             for (int i = 0; i < 4; i++)
                 winMask[getIdx(col + i * dCol, 7 - (row + i * dRow))] = true;
-            return playerAtPos;
+            return pAtPos;
         }
         return (int8_t)0;
     };
-
+    for (int r = 0; r < 6; r++)
-    for (int row = 0; row < 6; row++)
+        for (int c = 0; c < 4; c++)
-        for (int col = 0; col < 4; col++)
         {
-            int8_t result = checkMatch(col, row, 1, 0);
+            int8_t res = checkMatch(c, r, 1, 0);
-            if (result)
+            if (res)
-                return result;
+                return res;
         }
-    for (int row = 0; row < 3; row++)
+    for (int r = 0; r < 3; r++)
-        for (int col = 0; col < 7; col++)
+        for (int c = 0; c < 7; c++)
         {
-            int8_t result = checkMatch(col, row, 0, 1);
+            int8_t res = checkMatch(c, r, 0, 1);
-            if (result)
+            if (res)
-                return result;
+                return res;
         }
-    for (int row = 0; row < 3; row++)
+    for (int r = 0; r < 3; r++)
-        for (int col = 0; col < 4; col++)
+        for (int c = 0; c < 4; c++)
         {
-            int8_t result = checkMatch(col, row, 1, 1);
+            int8_t res = checkMatch(c, r, 1, 1);
-            if (result)
+            if (res)
-                return result;
+                return res;
         }
-    for (int row = 3; row < 6; row++)
+    for (int r = 3; r < 6; r++)
-        for (int col = 0; col < 4; col++)
+        for (int c = 0; c < 4; c++)
         {
-            int8_t result = checkMatch(col, row, 1, -1);
+            int8_t res = checkMatch(c, r, 1, -1);
-            if (result)
+            if (res)
-                return result;
+                return res;
         }
     return 0;
 }
 
 int minimax(int depth, int alpha, int beta, bool isMax, int8_t aiPlayer, int8_t humanPlayer, int8_t rootCol)
 {
+    if (depth % 2 == 0)
+    {
+        if (digitalRead(ENC_SW) == LOW)
+        {
+            abortAi = true;
+            return 0;
+        }
+    }
     if (depth >= current_look_ahead - 1)
         updateThinkingVisuals(aiPlayer, rootCol);
     else
         yield();
+    if (abortAi)
+        return 0;
 
-    // Check winner via temporary scan (logic check only)
     int8_t winner = scanBoard();
     if (winner == aiPlayer)
-        return 1000 + depth;
+        return 1000 + depth; // Win sooner is better
     if (winner == humanPlayer)
-        return -1000 - depth;
+        return -1000 - depth; // Lose later is better
     if (depth == 0 || isBoardFull())
         return 0;
 
     int colOrder[] = {3, 2, 4, 1, 5, 0, 6};
-    int bestScore = isMax ? -2000 : 2000;
+    int bestScore = isMax ? -10000 : 10000;
+
     for (int column : colOrder)
     {
+        if (abortAi)
+            return 0;
         int row = getFirstEmptyRow(column);
         if (row != -1)
         {
@@ -288,13 +294,14 @@ int minimax(int depth, int alpha, int beta, bool isMax, int8_t aiPlayer, int8_t
 
 void performAiMove(int8_t aiPlayer)
 {
+    abortAi = false;
     int humanPlayer = (aiPlayer == 1) ? 2 : 1;
     int bestScore = -30000;
     int bestCol = 3;
     int originalPly = current_look_ahead;
     current_look_ahead = (gameState == DEMO) ? demoPly : getDynamicPly();
 
-    // Instant win/block logic
+    // PHASE 1: Immediate Win Check (OFFENSE)
     for (int column = 0; column < COLS; column++)
     {
         int row = getFirstEmptyRow(column);
@@ -305,21 +312,34 @@ void performAiMove(int8_t aiPlayer)
             {
                 board[column][row] = 0;
                 bestCol = column;
-                goto finalizeMove;
+                goto finalizeMove; // TAKE THE WIN IMMEDIATELY
-            }
-            board[column][row] = humanPlayer;
-            if (current_look_ahead >= 2 && scanBoard() == humanPlayer)
-            {
-                board[column][row] = 0;
-                bestCol = column;
-                goto finalizeMove;
             }
             board[column][row] = 0;
         }
     }
 
+    // PHASE 2: Immediate Block Check (DEFENSE)
+    for (int column = 0; column < COLS; column++)
+    {
+        int row = getFirstEmptyRow(column);
+        if (row != -1)
+        {
+            board[column][row] = humanPlayer;
+            if (scanBoard() == humanPlayer)
+            {
+                board[column][row] = 0;
+                bestCol = column;
+                goto finalizeMove; // MUST BLOCK
+            }
+            board[column][row] = 0;
+        }
+    }
+
+    // PHASE 3: Minimax Look-ahead
     for (int column : {3, 2, 4, 1, 5, 0, 6})
     {
+        if (abortAi)
+            goto finalizeMove;
         int row = getFirstEmptyRow(column);
         if (row != -1)
         {
@@ -334,7 +354,7 @@ void performAiMove(int8_t aiPlayer)
         }
     }
 
-    if ((gameState == DEMO || blunder_enabled) && random(100) < 20)
+    if ((gameState == DEMO || blunder_enabled) && random(100) < 20 && !abortAi)
     {
         int randomColumn = random(0, 7);
         if (getFirstEmptyRow(randomColumn) != -1)
@@ -343,26 +363,19 @@ void performAiMove(int8_t aiPlayer)
 
 finalizeMove:
     current_look_ahead = originalPly;
-    moveDiscToCol(activeCol, bestCol, aiPlayer, 100);
+    if (!abortAi)
-    delay(450);
+    {
-    animateDrop(bestCol, aiPlayer);
+        moveDiscToCol(activeCol, bestCol, aiPlayer, 100);
+        delay(450);
+        animateDrop(bestCol, aiPlayer);
+    }
 }
 
-// --- Web Portal ---
-
 void handleRoot()
 {
-    String html = "<html><head><meta name='viewport' content='width=device-width, initial-scale=1'>"
+    String html = "<html><head><meta name='viewport' content='width=device-width, initial-scale=1'><style>body{font-family:sans-serif;background:#121212;color:white;text-align:center;} .card{background:#222;padding:25px;border-radius:15px;display:inline-block;margin-top:20px;} input{width:100%;padding:10px;margin:10px 0;border-radius:5px;border:none;}</style></head><body><h1>Connect 4 Admin</h1><div class='card'><form action='/save' method='POST'>";
-                  "<style>body{font-family:sans-serif;background:#121212;color:white;text-align:center;}"
+    html += "Base AI Ply:<input type='number' name='ply' value='" + String(current_look_ahead) + "'>Brightness:<input type='number' name='br' value='" + String(current_brightness) + "'>Idle Timeout (s):<input type='number' name='idle' value='" + String(current_idle_timeout_ms / 1000) + "'>";
-                  " .card{background:#222;padding:25px;border-radius:15px;display:inline-block;margin-top:20px;}"
+    html += "Blunders: <input type='checkbox' name='blunder' " + String(blunder_enabled ? "checked" : "") + "><br>Evolution: <input type='checkbox' name='evolve' " + String(progressive_difficulty ? "checked" : "") + "><br><br><input type='submit' value='Save' style='background:#28a745;color:white;'></form></div></body></html>";
-                  " input{width:100%;padding:10px;margin:10px 0;border-radius:5px;border:none;}</style></head><body>";
-    html += "<h1>Connect 4 Admin</h1><div class='card'><form action='/save' method='POST'>";
-    html += "Base AI Ply (1-10):<input type='number' name='ply' value='" + String(current_look_ahead) + "'>";
-    html += "Brightness (5-255):<input type='number' name='br' value='" + String(current_brightness) + "'>";
-    html += "Idle Timeout (Sec):<input type='number' name='idle' value='" + String(current_idle_timeout_ms / 1000) + "'>";
-    html += "Enable Blunders: <input type='checkbox' name='blunder' " + String(blunder_enabled ? "checked" : "") + "><br>";
-    html += "Evolution Mode: <input type='checkbox' name='evolve' " + String(progressive_difficulty ? "checked" : "") + "><br><br>";
-    html += "<input type='submit' value='Save Settings' style='background:#28a745;color:white;font-weight:bold;'></form></div></body></html>";
     server.send(200, "text/html", html);
 }
 
@@ -381,9 +394,8 @@ void handleSave()
     }
     if (server.hasArg("idle"))
     {
-        uint32_t s = server.arg("idle").toInt();
+        current_idle_timeout_ms = server.arg("idle").toInt() * 1000;
-        current_idle_timeout_ms = s * 1000;
+        prefs.putUInt("idle", current_idle_timeout_ms / 1000);
-        prefs.putUInt("idle", s);
     }
     blunder_enabled = server.hasArg("blunder");
     prefs.putBool("blunder", blunder_enabled);
@@ -405,13 +417,13 @@ void showMenu()
 #endif
     if (menuMode < 2)
     {
-        CRGB p1Col = (menuMode == 1) ? CRGB::Red : CRGB::Yellow;
+        CRGB pCol = (menuMode == 1) ? CRGB::Red : CRGB::Yellow;
         for (int y = 3; y <= 6; y++)
-            leds[getIdx(3, y)] = p1Col;
+            leds[getIdx(3, y)] = pCol;
-        leds[getIdx(2, 3)] = p1Col;
+        leds[getIdx(2, 3)] = pCol;
-        leds[getIdx(4, 3)] = p1Col;
+        leds[getIdx(4, 3)] = pCol;
-        leds[getIdx(2, 6)] = p1Col;
+        leds[getIdx(2, 6)] = pCol;
-        leds[getIdx(4, 6)] = p1Col;
+        leds[getIdx(4, 6)] = pCol;
     }
     else
     {
@@ -441,7 +453,6 @@ void setup()
     current_idle_timeout_ms = prefs.getUInt("idle", 60) * 1000;
     blunder_enabled = prefs.getBool("blunder", false);
     progressive_difficulty = prefs.getBool("evolve", false);
-
     FastLED.addLeds<WS2812B, LED_PIN, GRB>(leds, NUM_LEDS);
     FastLED.setBrightness(current_brightness);
     pinMode(ENC_SW, INPUT_PULLUP);
@@ -459,23 +470,25 @@ void loop()
     long newPos = myEnc.read() / SENSITIVITY;
     bool pressed = (digitalRead(ENC_SW) == LOW);
 
-    // Activity check
     if (newPos != oldEncPos || (pressed && (millis() - lastActivityTime > 500)))
     {
         if (gameState >= 2 || gameState == DEMO)
         {
-            for (int index = 0; index < 10; index++)
+            abortAi = true;
-            {
-                fadeToBlackBy(leds, NUM_LEDS, 32);
-                FastLED.show();
-                delay(30);
-            }
-            delay(500);
-            gameState = MENU;
             memset(board, 0, sizeof(board));
+            winnerPlayer = 0;
+            demoResetTimer = 0;
+            for (int i = 0; i < 10; i++)
+            {
+                fadeToBlackBy(leds, NUM_LEDS, 40);
+                FastLED.show();
+                delay(20);
+            }
+            gameState = MENU;
             showMenu();
-            lastActivityTime = millis();
             oldEncPos = newPos;
+            lastActivityTime = millis();
+            delay(300);
             return;
         }
         lastActivityTime = millis();
@@ -550,17 +563,20 @@ void loop()
                     {
                         int8_t aiP = (menuMode == 0) ? 2 : 1;
                         performAiMove(aiP);
-                        lastActivityTime = millis(); // Reset after AI thinking
+                        lastActivityTime = millis();
-                        winnerPlayer = scanBoard();
+                        if (!abortAi)
-                        if (winnerPlayer != 0)
                         {
-                            gameState = FINISHED_WIN;
+                            winnerPlayer = scanBoard();
-                            demoResetTimer = millis();
+                            if (winnerPlayer != 0)
-                        }
+                            {
-                        else if (isBoardFull())
+                                gameState = FINISHED_WIN;
-                        {
+                                demoResetTimer = millis();
-                            gameState = FINISHED_DRAW;
+                            }
-                            demoResetTimer = millis();
+                            else if (isBoardFull())
+                            {
+                                gameState = FINISHED_DRAW;
+                                demoResetTimer = millis();
+                            }
                         }
                     }
                     else
@@ -578,24 +594,27 @@ void loop()
         FastLED.show();
         delay(600);
         performAiMove(currentPlayer);
-        winnerPlayer = scanBoard();
+        if (!abortAi)
-        if (winnerPlayer != 0)
         {
-            gameState = FINISHED_WIN;
+            winnerPlayer = scanBoard();
-            demoResetTimer = millis();
+            if (winnerPlayer != 0)
-        }
+            {
-        else if (isBoardFull())
+                gameState = FINISHED_WIN;
-        {
+                demoResetTimer = millis();
-            gameState = FINISHED_DRAW;
+            }
-            demoResetTimer = millis();
+            else if (isBoardFull())
-        }
+            {
-        else
+                gameState = FINISHED_DRAW;
-        {
+                demoResetTimer = millis();
-            currentPlayer = (currentPlayer == 1) ? 2 : 1;
+            }
+            else
+            {
+                currentPlayer = (currentPlayer == 1) ? 2 : 1;
+            }
         }
     }
     else
-    { // FINISHED state (WIN/DRAW)
+    {
         static uint32_t lastFlash = 0;
         static bool toggle = true;
         if (millis() - lastFlash > 300)
@@ -631,11 +650,5 @@ void loop()
             demoResetTimer = 0;
             demoPly = random(3, 7);
         }
-        if (pressed)
-        {
-            gameState = MENU;
-            showMenu();
-            delay(300);
-        }
     }
-}
+}