Data commit

Task/Validate-International-Securities-Identification-Number/Delphi/validate-international-securities-identification-number.delphi

@@ -0,0 +1,99 @@
+function StrToBase10(S: string): TByteDynArray;
+{Convert ASCII string to Base-10}
+{ASCII Digits converted to integer 0..9 }
+{ASCII Chars convert to bytes "A"=10, "B"=11, etc }
+var I: Integer;
+var B: byte;
+
+	procedure StoreByte(B: byte);
+	begin
+	SetLength(Result,Length(Result)+1);
+	Result[High(Result)]:=B;
+	end;
+
+begin
+SetLength(Result,0);
+for I:=1 to Length(S) do
+	begin
+	if S[I] in ['0'..'9'] then StoreByte(Byte(S[I])-$30)
+	else
+		begin
+		B:=(Byte(S[I])-$41)+10;
+		StoreByte(B div 10);
+		StoreByte(B mod 10);
+		end;
+	end;
+end;
+
+{Simplifies cases where we have to sum a two digit number}
+
+const DigitSum: array [0..18] of byte = (0,1,2,3,4,5,6,7,8,9,1,2,3,4,5,6,7,8,9);
+
+function LuhnTest(Nums: array of byte): boolean;
+{Perform Luhn Test of byte array}
+var I,J,Len,Sum,Sum1,Sum2: integer;
+var Rev: array of byte;
+begin
+Sum1:=0; Sum2:=0;
+Len:=High(Nums);
+for I:=Len downto 0 do
+ if ((I-Len) and 1)=0 then Sum1:=Sum1 + Nums[I]
+ else Sum2:=Sum2 + DigitSum[Nums[I]*2];
+Sum:=Sum1+Sum2;
+Result:=(Sum mod 10)=0;
+end;
+
+{String error types}
+
+type TStringErrors = (seNone,seLength,seCountry);
+
+function ValidateStr(IDStr: string): TStringErrors;
+{Validate string checking for incorrectly length}
+{And invalid country code}
+begin
+if Length(IDStr)<>12 then Result:=seLength
+else if not (IDStr[1] in ['a'..'z','A'..'Z']) or
+        not (IDStr[2] in ['a'..'z','A'..'Z']) then Result:=seCountry
+else Result:=seNone;
+end;
+
+
+
+procedure ValidateID(Memo: TMemo; IDStr: string);
+{Validate and display status of string}
+var BA: TByteDynArray;
+var LT: boolean;
+var SE: TStringErrors;
+var S: string;
+begin
+SE:=ValidateStr(IDStr);
+BA:=StrToBase10(IDStr);
+LT:=LuhnTest(BA);
+if LT and (SE=seNone) then Memo.Lines.Add(IDStr+': Valid')
+else
+	begin
+	S:=IDStr+': Invalid';
+	if not LT then S:=S+', Luhn Error';
+	case SE of
+	 seLength: S:=S+', Length Error';
+	 seCountry: S:=S+', Country Code Error';
+	 end;
+	Memo.Lines.Add(S);
+	end;
+end;
+
+
+
+procedure ValidateSecuritiesID(Memo: TMemo);
+var BA: TByteDynArray;
+var I: integer;
+var S: string;
+begin
+ValidateID(Memo,'US0378331005');
+ValidateID(Memo,'US0373831005');
+ValidateID(Memo,'U50378331005');
+ValidateID(Memo,'US03378331005');
+ValidateID(Memo,'AU0000XVGZA3');
+ValidateID(Memo,'AU0000VXGZA3');
+ValidateID(Memo,'FR0000988040');
+end;