import sys
import os
import datetime
import subprocess as sp

# Add the directory containing this script to sys.path for local imports
script_dir = os.path.dirname(os.path.abspath(__file__))
sys.path.insert(0, script_dir)

from lark import Lark
import code_gen
import post

def escape_fortran_string(s):
    # Escape double quotes by doubling them
    escaped = s.replace('"', '""')
    # Split by newline and format as Fortran concatenation with char(10)
    lines = escaped.splitlines()
    if not lines:
        return '""'
    formatted_lines = [f'"{line}"' for line in lines]
    return ' // char(10) // &\n    '.join(formatted_lines)

def main():
    if len(sys.argv) < 2:
        print("Usage: python3 build_info_gen.py <termspec_file>")
        sys.exit(1)
        
    terms_file = sys.argv[1]
    with open(terms_file, 'r', encoding='utf-8') as f:
        terms_raw = f.read()
        
    # Generate Version Info
    vinfo = code_gen.VersionInfo(terms_raw)
    build_info_str = vinfo.fparams()
    
    # Generate LaTeX equations
    parser = Lark(code_gen.calc_grammar,
                  parser='lalr',
                  lexer_callbacks={
                      'ESCAPED_STRING': code_gen.tok_to_str,
                      'INT': code_gen.tok_to_int,
                      'BOOL': code_gen.tok_to_bool
                  })
    tree = parser.parse(terms_raw)
    ir1 = post.Stage1(tree)
    ir2 = post.Stage2(ir1)
    ir3 = post.Stage3(ir2)
    ir4 = post.Stage4(ir3)
    
    latex_lines = ["{"]
    for avg in ir4.averaged.values():
        latex_lines.append(f'  "{avg.name}" : r"${avg.latex}$",')
    latex_lines.append("}")
    latex_str = "\n".join(latex_lines)
    
    # Format for Fortran
    fortran_build_info = escape_fortran_string(build_info_str)
    fortran_latex = escape_fortran_string(latex_str)
    
    # Write m_build_info.f90
    fortran_code = f"""module m_build_info
  implicit none
  character(len=*), parameter :: build_info_str = &
    {fortran_build_info}
  character(len=*), parameter :: latex_equations_str = &
    {fortran_latex}
end module m_build_info
"""
    # Print to stdout so it can be redirected
    print(fortran_code)

if __name__ == "__main__":
    main()