add User class

.idea/vcs.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+    <mapping directory="$PROJECT_DIR$/src" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file

.idea/workspace.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ChangeListManager">
-    <list default="true" id="7be08370-19a4-4528-ab9b-d4cb0ec736c4" name="Default Changelist" comment="" />
+    <list default="true" id="7be08370-19a4-4528-ab9b-d4cb0ec736c4" name="Default Changelist" comment="">
+      <change afterPath="$PROJECT_DIR$/.idea/vcs.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/User.java" beforeDir="false" />
+    </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -14,7 +18,11 @@
       </list>
     </option>
   </component>
+  <component name="Git.Settings">
+    <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$/src" />
+  </component>
   <component name="ProjectId" id="1Zsmu4mM7KcQDh52oJP40I8FmWM" />
+  <component name="ProjectLevelVcsManager" settingsEditedManually="true" />
   <component name="ProjectViewState">
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showExcludedFiles" value="true" />
@@ -22,9 +30,24 @@
   </component>
   <component name="PropertiesComponent">
     <property name="RunOnceActivity.ShowReadmeOnStart" value="true" />
+    <property name="SHARE_PROJECT_CONFIGURATION_FILES" value="true" />
     <property name="WebServerToolWindowFactoryState" value="false" />
     <property name="aspect.path.notification.shown" value="true" />
   </component>
+  <component name="RunManager">
+    <configuration name="Othello" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="Othello" />
+      <module name="MyOthello" />
+      <method v="2">
+        <option name="Make" enabled="true" />
+      </method>
+    </configuration>
+    <recent_temporary>
+      <list>
+        <item itemvalue="Application.Othello" />
+      </list>
+    </recent_temporary>
+  </component>
   <component name="SvnConfiguration">
     <configuration />
   </component>
@@ -36,10 +59,56 @@
       <option name="presentableId" value="Default" />
       <updated>1585636394558</updated>
       <workItem from="1585636407800" duration="72000" />
+      <workItem from="1585656097487" duration="2378000" />
+      <workItem from="1585659438353" duration="9321000" />
+      <workItem from="1585687211713" duration="16102000" />
+      <workItem from="1585733466673" duration="521000" />
     </task>
     <servers />
   </component>
   <component name="TypeScriptGeneratedFilesManager">
     <option name="version" value="1" />
   </component>
+  <component name="WindowStateProjectService">
+    <state x="574" y="97" key="#com.intellij.ide.util.MemberChooser" timestamp="1585694421216">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state x="574" y="97" key="#com.intellij.ide.util.MemberChooser/0.0.1536.824@0.0.1536.824" timestamp="1585694421216" />
+    <state width="1493" height="201" key="GridCell.Tab.0.bottom" timestamp="1585703421720">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="201" key="GridCell.Tab.0.bottom/0.0.1536.824@0.0.1536.824" timestamp="1585703421720" />
+    <state width="1493" height="201" key="GridCell.Tab.0.center" timestamp="1585703421720">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="201" key="GridCell.Tab.0.center/0.0.1536.824@0.0.1536.824" timestamp="1585703421720" />
+    <state width="1493" height="201" key="GridCell.Tab.0.left" timestamp="1585703421720">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="201" key="GridCell.Tab.0.left/0.0.1536.824@0.0.1536.824" timestamp="1585703421720" />
+    <state width="1493" height="201" key="GridCell.Tab.0.right" timestamp="1585703421720">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="201" key="GridCell.Tab.0.right/0.0.1536.824@0.0.1536.824" timestamp="1585703421720" />
+    <state width="1493" height="182" key="GridCell.Tab.1.bottom" timestamp="1585671521268">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="182" key="GridCell.Tab.1.bottom/0.0.1536.824@0.0.1536.824" timestamp="1585671521268" />
+    <state width="1493" height="182" key="GridCell.Tab.1.center" timestamp="1585671521268">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="182" key="GridCell.Tab.1.center/0.0.1536.824@0.0.1536.824" timestamp="1585671521268" />
+    <state width="1493" height="182" key="GridCell.Tab.1.left" timestamp="1585671521267">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="182" key="GridCell.Tab.1.left/0.0.1536.824@0.0.1536.824" timestamp="1585671521267" />
+    <state width="1493" height="182" key="GridCell.Tab.1.right" timestamp="1585671521268">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state width="1493" height="182" key="GridCell.Tab.1.right/0.0.1536.824@0.0.1536.824" timestamp="1585671521268" />
+    <state x="813" y="283" key="com.intellij.ide.util.TipDialog" timestamp="1585733471645">
+      <screen x="0" y="0" width="1536" height="824" />
+    </state>
+    <state x="813" y="283" key="com.intellij.ide.util.TipDialog/0.0.1536.824@0.0.1536.824" timestamp="1585733471645" />
+  </component>
 </project>
\ No newline at end of file

src/Block.java

@@ -17,12 +17,12 @@ public class Block {
         this.color = color;
     }
 
-    public Character changeColor(){
+    public void changeColor(){
         if (color.equals('b')){
-            return 'w';
+            setColor('w');
         }
         else
-            return 'c';
+            setColor('b');
     }
 
     public int getRow() {

src/User.java

+import java.util.ArrayList;
+
+public class User {
+    private ArrayList<Block> userBlocks;
+    private ArrayList<Block> availableBlocksToPick;
+    private char color;
+
+    public User(){
+        userBlocks = new ArrayList<Block>();
+        availableBlocksToPick = new ArrayList<Block>();
+    }
+    public void addBlock(Block block){
+        userBlocks.add(block);
+    }
+
+    public boolean isAvailableBlockToPick(Block block , ArrayList<Block> blocks ) {
+        int i, j;
+        int flag1 = 0;
+        int flag2 = 0;
+        int flag3 = 0;// to know you can pick an empty block with help of checking changing color
+        if (!block.getColor().equals('n')) {
+            return false;
+        }
+
+        //check down
+        for (i = block.getRow(); i > 8; i++) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getRow() == block.getRow() + 1 && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getRow() == i && block1.getColumn() == block.getColumn() && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+
+        //check up
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getRow() - 1; i >= 0; i--) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getRow() == block.getRow() - 1 && block1.getColumn() == block.getColumn() && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getRow() == i && block1.getColumn() == block.getColumn() && block1.getColor().equals(color)) {
+
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+        //check right
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getColumn() + 1; i < 8; i++) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getColumn() == block.getColumn() + 1 && block1.getRow() == block.getRow() && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getColumn() == i && block1.getRow() == block.getRow() && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+
+        //check left
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getColumn() - 1; i >= 0; i--) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getColumn() == block.getColumn() - 1 && block1.getRow() == block.getRow() && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getColumn() == i && block1.getRow() == block.getRow() && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+
+        //check up and right
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getColumn() + 1, j = block.getRow() - 1; i < 8 && j > -1; i++, j--) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getColumn() == block.getColumn() + 1 && block1.getRow() == block.getRow() + 1 && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getColumn() == i && block1.getRow() == j && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+
+        //check down and left
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getColumn() - 1, j = block.getRow() + 1; i > -1 && j < 8; i--, j++) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getColumn() == block.getColumn() - 1 && block1.getRow() == block.getRow() + 1 && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getColumn() == i && block1.getRow() == j && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+
+        //check down and right
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getColumn() + 1, j = block.getRow() + 1; i < 8 && j < 8; i++, j++) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getColumn() == block.getColumn() + 1 && block1.getRow() == block.getRow() - 1 && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getColumn() == i && block1.getRow() == j && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+
+        //check up and left
+        flag1 = 0;
+        flag2 = 0;
+        for (i = block.getColumn() - 1, j = block.getRow() - 1; i < -1 && j < -1; i--, j--) {// find the next block with chosen block color
+            for (Block block1 : blocks) {
+                if (block1.getColumn() == block.getColumn() - 1 && block1.getRow() == block.getRow() - 1 && block1.getColor().equals(color)) {
+                    flag1 = 1;
+                    break;
+                }
+                if (flag2 == 1) {// to not change " w b b b w b b w " to "w w w w w w w w"
+                    break;
+                }
+                if (!block1.getColor().equals('n') && block1.getColumn() == i && block1.getRow() == j && block1.getColor().equals(color)) {
+                    flag2 = 1;
+                    flag3 = 1;
+                }
+            }
+            if (flag1 == 1)
+                break;
+        }
+
+        if (flag3 == 0) {
+            return false;
+        }
+        return true;
+    }
+
+
+   /*  public void updateAvailableBlockToPick(ArrayList<Block> blocks){
+        for (Block block : blocks){
+            if( isAvailableBlockToPick(block , blocks) == true){
+                availableBlocksToPick.add(block);
+            }
+        }
+
+     }*/
+
+    public void addAvailableBlockToPick(Block block){
+        availableBlocksToPick.add(block);
+    }
+
+    public void removeAvailableBlockToPick(Block block){
+        availableBlocksToPick.remove(block);
+    }
+
+    public char getColor() {
+        return color;
+    }
+
+    public void setColor(char color) {
+        this.color = color;
+    }
+
+}
+