using System.Collections.Generic;
using System.Linq;

namespace Rokojori;

public class ExpressionParser:ParserPhase
{
  public List<PrecedenceLevel> levels = [];

  public override void Process( Parser parser )
  {
    ProcessExpression( parser.root );
  }

  public void ProcessExpression( ASTNode expressionParent )
  {
    var parser = expressionParent.parser;

    for ( int i = 0; i < levels.Count; i++ )
    {
      var changed = levels[ i ].Process( expressionParent );

      if ( parser.hasErrors )
      {
        return;
      }

      if ( changed )
      {
        i = -1;
      }
    }
  }

  protected PrecedenceLevel AddPrecedenceLevel( params ExpressionOperator[] operators )
  {
    var level = new PrecedenceLevel();
    level.operators.AddRange( operators );

    var isFromRight = operators.Find( op => ! op.IsFromLeft() ) != null;
    level.fromLeft = ! isFromRight;

    this.levels.Add( level );
    return level;
  }
}