%option c++
%option noyywrap
%option yyclass="Scanner"
%x STRING

%{
#include "scanner.hpp"
#include "indent_stack.hpp"

%}

%%
^[ \t]*\r?\n            { /* Ignore lines containing whitespace only */ }
^[ \t]*#.*\n            { /* Ignore comment-only lines */ }

^[ \t]+ {
    int col = indent_stack.calculateColumn(yytext, yyleng);
    auto action = indent_stack.updateIndentation(col);

    if (action == IndentAction::Indent) return yy::parser::token::TOK_INDENT;
    if (action == IndentAction::Dedent) return yy::parser::token::TOK_DEDENT;
}


\n                      { return yy::parser::token::TOK_NEWLINE; }

def                     { return yy::parser::token::TOK_KW_DEF; }
if                      { return yy::parser::token::TOK_KW_IF; }
return                  { return yy::parser::token::TOK_KW_RETURN; }
for                     { return yy::parser::token::TOK_KW_FOR; }
in                      { return yy::parser::token::TOK_KW_IN; }

\(                      { return yy::parser::token::TOK_L_PAREN; }
\)                      { return yy::parser::token::TOK_R_PAREN; }
\:                      { return yy::parser::token::TOK_COLON; }
\=                      { return yy::parser::token::TOK_ASSIGN; }
\+                      { return yy::parser::token::TOK_PLUS; }
\-                      { return yy::parser::token::TOK_MINUS; }

\"                      { yymore(); BEGIN(STRING); }
<STRING>\"              { BEGIN(INITIAL); yylval->as<std::string>() = yytext; return yy::parser::token::TOK_STRING; }
<STRING>.               { yymore(); }

[0-9]+                  { yylval->as<std::string>() = yytext; return yy::parser::token::TOK_NUMBER; }
[A-Za-z_][A-Za-z0-9_]*  { yylval->as<std::string>() = yytext; return yy::parser::token::TOK_IDENTIFIER; }

<<EOF>>                 { return yy::parser::token::TOK_EOF; }
.                       { }