using CanonSharp.Pascal.Scanner;
using CanonSharp.Tests.Utils;

namespace CanonSharp.Tests.ScannerTests;

public class LexicalParserTests : LexicalTestBase
{
    [Fact]
    public void LexicalParserTest1()
    {
        const string pascalProgram = """
                                     program HelloWorld;
                                     var
                                     message: char;
                                     begin
                                     message := 'h';
                                     writeln(message);
                                     end.
                                     """;

        ValidateLexicalTokens(LexicalScanner.PascalParser(), pascalProgram, [
            (LexicalTokenType.Keyword, "program"),
            (LexicalTokenType.Identifier, "HelloWorld"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "var"),
            (LexicalTokenType.Identifier, "message"),
            (LexicalTokenType.Delimiter, ":"),
            (LexicalTokenType.Keyword, "char"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "begin"),
            (LexicalTokenType.Identifier, "message"),
            (LexicalTokenType.Operator, ":="),
            (LexicalTokenType.Character, "h"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Identifier, "writeln"),
            (LexicalTokenType.Delimiter, "("),
            (LexicalTokenType.Identifier, "message"),
            (LexicalTokenType.Delimiter, ")"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "end"),
            (LexicalTokenType.Delimiter, ".")
        ]);
    }

    [Fact]
    public void LexicalParserTest2()
    {
        const string program = """
                               program main;
                               var
                                 ab: integer;
                               begin
                                 ab := 3;
                                 write(ab);
                               end.
                               """;

        ValidateLexicalTokens(LexicalScanner.PascalParser(), program, [
            (LexicalTokenType.Keyword, "program"),
            (LexicalTokenType.Identifier, "main"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "var"),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Delimiter, ":"),
            (LexicalTokenType.Keyword, "integer"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "begin"),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Operator, ":="),
            (LexicalTokenType.ConstInteger, "3"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Identifier, "write"),
            (LexicalTokenType.Delimiter, "("),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Delimiter, ")"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "end"),
            (LexicalTokenType.Delimiter, ".")
        ]);
    }

    [Fact]
    public void LexicalParserTest3()
    {
        const string pascalProgram = """
                                     {test}
                                     program main;
                                     var
                                       ab, ba: integer;
                                     begin
                                       ab := 3;
                                       ba := 5;
                                       ab := 5;
                                       write(ab + ba);
                                     end.
                                     """;

        ValidateLexicalTokens(LexicalScanner.PascalParser(), pascalProgram, [
            (LexicalTokenType.Keyword, "program"),
            (LexicalTokenType.Identifier, "main"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "var"),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Delimiter, ","),
            (LexicalTokenType.Identifier, "ba"),
            (LexicalTokenType.Delimiter, ":"),
            (LexicalTokenType.Keyword, "integer"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "begin"),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Operator, ":="),
            (LexicalTokenType.ConstInteger, "3"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Identifier, "ba"),
            (LexicalTokenType.Operator, ":="),
            (LexicalTokenType.ConstInteger, "5"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Operator, ":="),
            (LexicalTokenType.ConstInteger, "5"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Identifier, "write"),
            (LexicalTokenType.Delimiter, "("),
            (LexicalTokenType.Identifier, "ab"),
            (LexicalTokenType.Operator, "+"),
            (LexicalTokenType.Identifier, "ba"),
            (LexicalTokenType.Delimiter, ")"),
            (LexicalTokenType.Delimiter, ";"),
            (LexicalTokenType.Keyword, "end"),
            (LexicalTokenType.Delimiter, ".")
        ]);
    }

    [Fact]
    public void LexicalParserTest4()
    {
        ValidateLexicalTokens(LexicalScanner.PascalParser(), "array [0..9] of integer", [
            (LexicalTokenType.Keyword, "array"),
            (LexicalTokenType.Delimiter, "["),
            (LexicalTokenType.ConstInteger, "0"),
            (LexicalTokenType.Delimiter, ".."),
            (LexicalTokenType.ConstInteger, "9"),
            (LexicalTokenType.Delimiter, "]"),
            (LexicalTokenType.Keyword, "of"),
            (LexicalTokenType.Keyword, "integer")
        ]);
    }

    [Theory]
    [InlineData("""
                program exFunction;
                var
                a, b, ret : integer;

                begin
                     a := 100;
                     b := 200;
                     { calling a function to get max valued }
                     ret := a - b;



                end.
                """, 29)]
    [InlineData("""
                {
                    This is a block comment that does closed.
                  }
                program CommentClosed;
                """, 3)]
    [InlineData("""
                {}
                program CommentClosed;
                """, 3)]
    public void LexicalParserTest(string input, int count)
    {
        LexicalScanner scanner = new();

        List<LexicalToken> tokens = scanner.Tokenize(new StringReadState(input)).ToList();
        Assert.Equal(count, tokens.Count);
    }
}