Dim Shared As Integer celdasXLado, contarMovs
Dim Shared As String movsValidos, inicioBS, actualBS, objetivoBS

Sub mostrarTablero (fila As Integer, columna As Integer, junto As String, titulo As String)
    Dim As Integer i, j

    Locate fila - 1, columna: Print titulo
    For i = 1 To celdasXLado
        Locate fila, columna + 2 * (i-1) + 3: Print Mid(movsValidos, i, 1);
    Next i
    Print
    For i = 1 To celdasXLado
        Locate fila + i, columna - 1: Print Str(i);
        For j = 1 To celdasXLado
            Locate fila + i, columna + 2 * j: Print " " + Mid(junto, (i-1) * celdasXLado + j, 1);
        Next j
        Print
    Next i
End Sub

Sub mostrarEstado
    Color  9: mostrarTablero 2, 2, actualBS, "Current:"
    Color 12: mostrarTablero 2, 2 + 2 * celdasXLado + 6, objetivoBS, " Target:"
    Color 13: Print !"\n Number of moves taken so far is " + Str(contarMovs)
    Color 14
End Sub

Function Pistas() As String 'compare the currentB to targetB and suggest letter or digit or done
    Dim As Integer i, j
    Dim As Boolean flag = False
    Dim As String r, actualBitS, objetivoBitS

    For i = 1 To 2 * celdasXLado 'check cols first then rows as listed in movsValidos
        r = Mid(movsValidos, i, 1)
        If i <= celdasXLado Then
            actualBitS = Mid(actualBS, i, 1): objetivoBitS = Mid(objetivoBS, i, 1)
            If actualBitS <> objetivoBitS Then flag = False: Exit For
        Else
            j = i - celdasXLado
            actualBitS   = Mid(actualBS, (j - 1) * celdasXLado + 1, 1)
            objetivoBitS = Mid(objetivoBS, (j - 1) * celdasXLado + 1, 1)
            If actualBitS <> objetivoBitS Then flag = False: Exit For
        End If
    Next i
    Pistas = Iif(flag, r, "Done?")
End Function

Sub Centrar (fila As Integer, texto As String) 'center print at fila
    Locate fila, (80 - Len(texto)) / 2: Print texto;
End Sub

Sub vcls 'print the screen to file then clear it
    Dim As String sc(23), scan
    Dim As Integer lineas, t, final, i

    For lineas = 1 To 23
        For t = 1 To 80: scan &= Chr(Screen(lineas, t)): Next t
        sc(lineas) = Rtrim(scan)
        scan = ""
    Next lineas
    For final = 23 To 1 Step -1
        If sc(final) <> "" Then Exit For
    Next final
    Print #3, ""
    For i = 1 To final: Print #3, sc(i): Next i
    Print #3, "": Print #3, String(80, "-"): Cls
End Sub

Function TeclaPulsada() As String 'just want printable characters
    Dim As String KBD = ""

    While Len(KBD) = 0
        KBD = Inkey
        If Len(KBD) Then 'press something so respond
            If Len(KBD) = 2 Or Asc(KBD) > 126 Or Asc(KBD) < 32 Then KBD = "*"
        End If
    Wend
    Return KBD
End Function

Function inicioTablero() As String
    Dim As String r

    For i As Integer = 1 To celdasXLado ^ 2
        r &= Ltrim(Str(Int(Rnd * 2)))
    Next i
    Return r
End Function

Sub hacerMovim (moveS As String)
    Dim As Uinteger ac = Asc(moveS)
    Dim As Integer i, columna, fila
    Dim As String bitS

    If ac > 96 Then 'letter
        columna = ac - 96
        For i = 1 To celdasXLado
            bitS = Mid(actualBS, (i - 1) * celdasXLado + columna, 1)
            Mid(actualBS, (i-1) * celdasXLado + columna, 1) = Iif(bitS = "0", "1", "0")
        Next
    Else 'number
        fila = ac - 48
        For i = 1 To celdasXLado
            bitS = Mid(actualBS, (fila-1) * celdasXLado + i, 1)
            Mid(actualBS, (fila-1) * celdasXLado + i, 1) = Iif(bitS = "0", "1", "0")
        Next i
    End If
End Sub

Function hacerObjetivo() As String
    While actualBS = inicioBS
        For i As Integer = 1 To celdasXLado * celdasXLado
            Dim As String mS = Mid(movsValidos, Int(Rnd * Len(movsValidos)) + 1, 1)
            hacerMovim mS
        Next i
    Wend
    Return actualBS
End Function

Sub Intro
    Dim As Integer i
    Dim As String inS

    Close
    Open "Copy Flipping Bits Game.txt" For Output As #3
    celdasXLado = 0: movsValidos = "": contarMovs = 0
    Color 9: Centrar 3, "Flipping Bits Game (with AI!)  JHG 31/05/2023"
    Color 5
    Centrar 5, "You will be presented with a square board marked Current and"
    Centrar 6, "another marked Target. The object of the game is to match"
    Centrar 7, "the Current board to Target in the least amount of moves."
    Centrar 9, "To make a move, enter a letter for a column to flip or"
    Centrar 10, "a digit for a fila to flip. In a flip, all 1's are"
    Centrar 11, "changed to 0's and all 0's changed to 1's."
    Centrar 13, "You may enter 0 or q at any time to quit."
    Centrar 14, "You may press ? when prompted for move to get a hint."
    Centrar 15, "You may press ! to have the program solve the puzzle."
    Color 14: Print: Print
    While celdasXLado < 2 Or celdasXLado > 9
        Locate Csrlin, 13: Print "Please press how many cells you want per side 2 to 9 > ";
        inS = TeclaPulsada: Print inS : Sleep .4
        If inS = "0" Or inS = "q" Then End Else celdasXLado = Val(inS)
    Wend
    vcls
    For i = 1 To celdasXLado: movsValidos = movsValidos + Chr(96 + i)  : Next i
    For i = 1 To celdasXLado: movsValidos = movsValidos + Ltrim(Str(i)): Next i
    inicioBS = inicioTablero
    actualBS = inicioBS
    objetivoBS = hacerObjetivo
    actualBS = inicioBS
End Sub

Sub MenuPrincipal
    Dim As String SiNo, mS, mvS
    Dim As Boolean mostrarSolucion = False, salir = False

    Do
        mostrarEstado
        If actualBS = objetivoBS Then 'game done!
            Print !"\n Congratulations, done in"; contarMovs; " moves."
            Print !"\n Press y for yes, if you want to start over > ";
            SiNo = TeclaPulsada: Print SiNo: Sleep .4: vcls
            If SiNo = "y" Then Intro Else salir = True
        Else 'get next move
            mS = " "
            While Instr(movsValidos, mS) = 0
                Print !"\n Press a lettered column or a numbered fila to flip (or 0,q,?,!) > ";
                mS = TeclaPulsada: Print mS: Sleep .4
                If mS = "!" Then
                    mostrarSolucion = True: mS = " ": Exit While
                    Elseif mS = "?" Then mS = " ": Centrar Csrlin, "Hint: " + Pistas
                    Elseif mS = "0" Or mS = "q" Then vcls: Close: End
                    Elseif mS = "" Then mS = " "
                End If
            Wend
            If mostrarSolucion Then 'run the solution from hints function
                mostrarSolucion = False: mvS = Pistas
                Centrar Csrlin + 1, "For the next move, the AI has chosen: " + mvS
                Centrar Csrlin + 1, "Running the solution with 4 sec screen sleeps..."
                Sleep 4: vcls
                While mvS <> "Done?"
                    contarMovs += 1
                    hacerMovim mvS
                    mostrarEstado
                    mvS = Pistas
                    Centrar Csrlin + 1, "For the next move, the AI has chosen: " + mvS
                    Centrar Csrlin + 1, "Running the solution with 4 sec screen sleeps..."
                    Sleep 4: vcls
                Wend
                mostrarEstado
                Centrar Csrlin + 1, "Done! Current board matches Target"
                Centrar Csrlin + 1, "Press y for yes, if you want to start over: > "
                SiNo = TeclaPulsada: Print SiNo: Sleep .4: vcls
                If SiNo = "y" Then Intro Else salir = True
            Else
                vcls
                contarMovs += 1
                hacerMovim mS
            End If
        End If
    Loop Until salir
    Close
End Sub

'--- Programa Principal ---
Randomize Timer
Intro
MenuPrincipal
End
'--------------------------