Winforms VB.Net: Best way to code rules for german cards game "Schafkopf"?

[Jo_vb net]

Since some weeks i'm working on a german cards game "Schafkopf" [private] demo. The demo is not bad but somehow my coding drifted away and appears like "Spaghetti code". The game has 32 cards and 4 players. For a "SOLO" or "WENZ" the declarer plays against the 3 other players. A standard game is that the declarer plays with one "Ace" (owned by another player) => 2 play against the other 2. The computer controls 3 players, one player is the user who can click on one of his cards (which are presented on a dgv). The problem is that there are many, many loops when checking a players cards and endless "rules" which now are done with "If, Then, ElseIf ..." statements. So one of the related functions is > 500 code lines ... I think I need a better concept, because the existing one is hard to handle, problems are not easy to fix. Any ideas? Example for those loops:

   Try
            If MyForm.GameOver = True Then Exit Function
            If GameStatus.ToString = "SpielAus" Then MyForm.GameOver = True
            If GameStatus.ToString = "SpielAus" Then Exit Function

            If sHandCards Is Nothing Then
                ' => LeadSuit n.a.
                Debug.Print("ACP 516 sHandCards: Is Nothing")
                Debug.Print("ACP 517 LeadSuitID: '" & LeadSuitID & "'; TrumpCardID: '" & TrumpCardID & "'")
                sHandCards = sTrumpList
            Else
                'sHandCards <> Nothing
                'MessageBox.Show("ACP 525 sHandCards: " & sHandCards.ToString)
                If ContainsHandCardsStandardTrumps(sHandCards) = False Then
                    'MessageBox.Show("ACP 528 sHandCards: " & sHandCards.ToString)
                    If TrumpCardID <> 4 Then sHandCards = sTrumpList
                    If TrumpCardID = 4 Then
                        If sHandCards.ToString.Contains("O") Then
                        Else
                            sHandCards = sTrumpList
                        End If
                    End If
                End If


                If dgv.CurrentCell.Value.ToString.Contains("♠") Or dgv.CurrentCell.Value.ToString.Contains("♥") Or 
                   dgv.CurrentCell.Value.ToString.Contains("Ⴖ") Or dgv.CurrentCell.Value.ToString.Contains("Ꚛ") Or 
                   dgv.CurrentCell.Value.ToString = "" Or dgv.CurrentCell.Value Is Nothing Or 
                   dgv.CurrentCell.Value.ToString = String.Empt

[Lost User]

Simple thing like:

string s = dgv.CurrentCell.Value.ToString

then

If s.Conttains("x") or s.Contains...etc

makes the thing more palatable. Then you look at it again; repeat.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

[Jo_vb net]

Thank you. Will use string s = dgv.CurrentCell.Value.ToString and remove redundant code lines. But the main question is if it makes sense using If - Then statements for game rules or if there is a better way to do this.

[Lost User]

Rules come in a form best suited for a given situation; be it "if's", tables or whatever. Your "if's" depend on the length of your "cell value". If it's only 1 (char) long, instead of multiple if's, you can code:

string s = "x"

if "xwz".Contains(s) etc.

if the cell value's length is greater than one, then iterate each character:

For Each ch As Char in s
if "xyx".Contains(ch) etc.
Next
}

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

[Lost User]

Instead of hard coding the rules, can you think of a way to load some rules from a list and check those?

Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

[Jo_vb net]

I had some ideas during the last days. It is not easy to find and fix issues with my Spaghetti Code - but the computer is already playing better than a human with beginner level. If I only could fix 4 or 5 important remaining issues the pc would reach medium playing level. One idea is to replace each loop with a Sub or Function (what is possible but I'm not sure it this makes sense). A list or a xml file came also to my mind - I searched for CP articles about rules engine or business rules. But from my findings there was nothing really easy - something that you can use easily and when you look at it some weeks later it should still look easy and allow changes without any problems. The last thing would be to have classes for card, hand cards, cards deck, current trick and so on. But I do not know how to bring together the properties of the classes and my existing rules. Any link to an article which may help me would be great. Note: My Schafkopf demo is based on A Bridge Card Game and Display Card Presentation[^]

[Lost User]

I think you could have found more current examples. [How to Build a Multiplayer Card Game with Unity 2D and Mirror (UPDATED)](https://www.freecodecamp.org/news/how-to-build-a-multiplayer-card-game-with-unity-2d-and-mirror/) [card-game · GitHub Topics · GitHub](https://github.com/topics/card-game?l=c%23) etc.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

[Lost User]

Jo_vb.net wrote:

but the computer is already playing better than a human with beginner level. If I only could fix 4 or 5 important remaining issues the pc would reach medium playing level.

You programmed it like that! Look into the "Random" object and force it to play a dumb card now and then (once out of five?).

Jo_vb.net wrote:

A list or a xml file came also to my mind - I searched for CP articles about rules engine or business rules.

Hehe, good idea; those tend to generalize to fit a lot of rules though. You want to keep it simpler; understand the concept enough to build a simpler version of your own. Remember that "xyz".Contains("c")? Imagine xyz and c coming from a file? It wouldn't be rules based, but halfway. If you can do that, we'll go from there to make actual rules :)

Jo_vb.net wrote:

The last thing would be to have classes for card, hand cards, cards deck, current trick and so on. But I do not know how to bring together the properties of the classes and my existing rules.

You could write multiple classes for a "card"; I'd talk about interfaces at this point if we'd be in class :D

Jo_vb.net wrote:

Any link to an article which may help me would be great.

I did not help in any way, and any suggestion may have sounded like homework for school. There's never a library that does exactly what you need. I can only point to CodeProject; they'd help. Conquer the rules; if you can do that, I'll write an article about depending on classes and having variants :thumbsup:

Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

[Lost User]

Are we a programming forum, or a Google service? :confused:

Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

[Jo_vb net]

Thank you for the links.

[Jo_vb net]

Thanks a lot for this detailed answer. But I'm only on a better beginner level in coding... I use already subs in my loops and I really don't understand how

Quote:

Remember that "xyz".Contains("c")? Imagine xyz and c coming from a file? It wouldn't be rules based, but halfway. If you can do that, we'll go from there to make actual rules

could be used for a loop like the following:

           If MyForm.RufAs.MeAlreadyPlayed = True Or MyForm.iCoSpieler = -1 Then
                For Each row As DataGridViewRow In dgv.Rows
                    For n As Integer = 1 To dgv.Columns.Count - 1
                        If MyForm.RufAs.MeAlreadyPlayed = True Or MyForm.iCoSpieler = -1 Then

                            If MyForm.Trick\_Content.CurrentTrickWinner <> MyForm.iCoSpieler AndAlso MyForm.Trick\_Content.CurrentTrickWinner <> DeclarerID Then
                                If n > 0 AndAlso PlayerID <> DeclarerID AndAlso PlayerID <> MyForm.iCoSpieler Then
                                    If TrumpCardID <> 4 Then

                                        If PlayTogether\_WenzUsage(dgvCell, PlayerID, DeclarerID, GameStatus, sTrumpList, TrumpCardID, "RufAs", MyForm, LeadSuitID) = True Then

                                            If row.Cells(n).Value.ToString.Contains("U") Then
                                                If ContainsHandCardsStandardTrumps(CStr(sHandCards)) = False Then ' Or sHandCards Is Nothing Then ' Or MyForm.cardLessThan(MyForm.Trick\_Content.PossibleWinnerCardString, row.Cells(n).Value.ToString & row.Cells(0).Value.ToString) Then
                                                    If LeadSuitID = TrumpCardID AndAlso row.Cells(n).Value.ToString <> String.Empty Then
                                                        SetCurrentCell(dgvCell, dgv, row.Cells(n), row.Cells(0), " ~ " & (String.Format("Line # {0}", (New StackTrace(New StackFrame(True))).GetFrame(0).GetFileLineNumber())) & " ~ ")
                                                    End If
                                                End If
                                            End If
                                        End If
                                    End If

                                End If
                            End If
                        End If
                    Next
                Next

[Lost User]

Jo_vb.net wrote:

But I'm only on a better beginner level in coding...

Lots of beginners here; most looking for templates to do their work.

Jo_vb.net wrote:

could be used for a loop like the following:

Don't worry about the big picture; understand the concept first, then you integrate it into your 'engine'. Someone hit me if I wrong, but string s = File.ReadAllText(path, appendText, Encoding.UTF8); would load the data of that file into the string called s? "xyz".Contains("c") becomes s.Contains("c") Where s is then loaded from a file (specified in "path"). This way, the "xyz" isn't hardcoded, but just data in a file. Requires you to read a string from a file. Could you achieve that?

Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

[Jo_vb net]

I'm in doubt about this approach [the .Contains(s) method is only used in < 10% of the "if - then" statements/rules], but reading a text file line after line is possible.

[Lost User]

The idea is not limited to that method :)

Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

[Lost User]

I could have just said "There are better examples". If someone said that to me, I would have responded: "And...?" So, I saw no point in responding as you might suggest. There, I wasted a message after all.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

[Jo_vb net]

Well this leads me to another improvement. Instead of many times using If statements like that

If PlayerID <> DeclarerID And PlayerID <> MyForm.iCoSpieler Then ...
or
If PlayerID = DeclarerID Or PlayerID = MyForm.iCoSpieler Then ...

I will use variables like

Dim bTeamDeclarer As Boolean
Dim bTeamOpponent As Boolean

If PlayerID <> DeclarerID And PlayerID <> MyForm.iCoSpieler Then bTeamOpponent = True
If PlayerID = DeclarerID Or PlayerID = MyForm.iCoSpieler Then bTeamDeclarer = True

Then i can combine 2 or 3 lines of my rules in the loops like

If n > 0 AndAlso bTeamDeclarer= True AndAlso row.Index = TrumpCardID Then
...

This should make code easier to read AND shorter.

[Lost User]

In c# I'd code:

// As a "property"
bool bTeamComponent => PlayerID != DeclarerID && PlayerID != MyForm.iCoSpieler;
...
// Then in a method:
if ( bTeamComponent ) ...

Note how bTeamComponent is "dynamic" for every access. It obviously has to be scoped properly.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

[Jo_vb net]

I do not want to learn Unity or Python. But I found a WPF project in a CP article with a cards deck where each card is a class object (which shows a card image) called PlayingCard. I've added some properties which I need for my game rules and migrated all I already had to WPF. All I have to do now is to re-write > 1000 code lines with the game rules. But the UI is much better then the old one.

[Lost User]

They were there for "design" ideas. You were asking for "best ways to code" (i.e. "patterns"). (I personally have never written a lick of VB.NET). But I see you get the idea: find a mouse trap (sample app) and build a better one.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I