import hashlib
# Import compiler components:
from . import lexer
from . import parser
from .codegenerator import CodeGenerator
from .nodes import ExportedSymbol

class Compiler:
   versie = '0.9.3'

   def __repr__(self):
      return 'LCFOS compiler {0}'.format(self.versie)

   def generateSignature(self, src):
      return hashlib.md5(bytes(src,encoding='ascii')).hexdigest()

   def compilesource(self, src):
      """ Front end that handles the stages: """
      tokens = lexer.tokenize(src) # Lexical stage
      ast = parser.Parser(tokens).parseModule() # Parse a module
      CodeGenerator().generatecode(ast)
      # Attach a signature:
      ast.signature = self.generateSignature(src)
      # Generate exported symbols:
      ast.exports = []
      for proc in ast.procs:
         if proc.public:
            sym = ExportedSymbol(proc.name, proc.typ)
            sym.imageoffset = proc.entrypoint
            ast.exports.append(sym)

      return ast