import os
import subprocess
import shutil
import uuid
import config

class JoernParser:
    def __init__(self):
        self.temp_dir = config.TEMP_DIR
        os.makedirs(self.temp_dir, exist_ok=True)

    def parse_code(self, source_code: str):
        """
        Takes raw C code string, saves it, runs Joern, and returns the GraphML path.
        """
        # 1. Create a unique session ID for this request
        session_id = str(uuid.uuid4())
        session_path = os.path.join(self.temp_dir, session_id)
        os.makedirs(session_path, exist_ok=True)

        # 2. Write the source code to a file
        src_file_path = os.path.join(session_path, "test.c")
        with open(src_file_path, "w") as f:
            f.write(source_code)

        # 3. Define output paths
        cpg_out_path = os.path.join(session_path, "cpg.bin")
        graph_out_path = os.path.join(session_path, "export.graphml")

        try:
            # 4. Run Joern Parse (C -> Binary CPG)
            cmd_parse = f"joern-parse {src_file_path} --output {cpg_out_path}"
            subprocess.run(cmd_parse, shell=True, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)

            # 5. Run Joern Export (Binary CPG -> GraphML)
            cmd_export = f"joern-export {cpg_out_path} --repr all --format graphml --out {session_path}/export"
            subprocess.run(cmd_export, shell=True, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)

            # 6. Locate the exported file (Prioritize export.xml)
            export_dir = os.path.join(session_path, "export")
            target_xml = os.path.join(export_dir, "export.xml")
            
            # CHECK 1: Explicitly look for export.xml
            if os.path.exists(target_xml):
                shutil.move(target_xml, graph_out_path)
                return graph_out_path, session_path
            
            # CHECK 2: Fallback scan (only if export.xml is missing)
            for file in os.listdir(export_dir):
                if file.endswith(".xml") or file.endswith(".graphml"):
                    shutil.move(os.path.join(export_dir, file), graph_out_path)
                    return graph_out_path, session_path

            raise Exception("GraphML file not found after export.")

        except subprocess.CalledProcessError as e:
            print(f"Joern Error: {e}")
            self.clean_up(session_path)
            raise e

    def clean_up(self, session_path):
        """Deletes the temporary files for this session."""
        if os.path.exists(session_path):
            shutil.rmtree(session_path)