import os
import sys
import shutil
import argparse
import win32com.client


def start_solid_edge():
    """Startet Solid Edge über COM."""
    print("Starting instance of SolidEdge...")
    se = win32com.client.Dispatch("SolidEdge.Application")
    se.Visible = True
    print("done\n")
    return se.Documents


def find_placeholder_occurrence(occurrences, placeholder_name):
    """Sucht die Occurrence mit dem Namen placeholder_name."""
    for occ in occurrences:
        filename = os.path.basename(occ.OccurrenceFileName)
        if filename.lower() == placeholder_name.lower():
            return occ
    return None


def process_part(par_name, par_path, dummy_asm_path, placeholder_name, work_dir, output_dir, documents):
    """Kopiert Dummy-ASM, ersetzt Platzhalter mit .par, speichert Ergebnis."""
    temp_asm = os.path.join(work_dir, "_temp.asm")
    temp_cfg = os.path.splitext(temp_asm)[0] + ".cfg"

    shutil.copyfile(dummy_asm_path, temp_asm)

    asm_doc = documents.Open(temp_asm)
    occurrences = asm_doc.Occurrences

    target_occ = find_placeholder_occurrence(occurrences, placeholder_name)

    if not target_occ:
        print(f"[{par_name}] Placeholder '{placeholder_name}' not found in 'dummy.asm'. Skipping.")
        asm_doc.Close(False)

        # Cleanup bei Fehler
        if os.path.exists(temp_asm):
            os.remove(temp_asm)
        if os.path.exists(temp_cfg):
            os.remove(temp_cfg)
        return

    print(f"[{par_name}] Replacing '{placeholder_name}' with '{par_name}'...")
    target_occ.Replace(par_path, True)

    ziel_name = os.path.splitext(par_name)[0] + ".asm"
    ziel_path = os.path.join(output_dir, ziel_name)

    asm_doc.SaveAs(ziel_path)
    print(f"→ Saved: {ziel_path}")

    asm_doc.Close(False)

    # Lösche ggf. erzeugte .cfg-Datei zur Ziel-ASM
    ziel_cfg = os.path.splitext(ziel_path)[0] + ".cfg"
    if os.path.exists(ziel_cfg):
        os.remove(ziel_cfg)

    # Lösche temporäre ASM und deren CFG
    if os.path.exists(temp_asm):
        os.remove(temp_asm)
    if os.path.exists(temp_cfg):
        os.remove(temp_cfg)


if __name__ == "__main__":
    # Argumente parsen
    parser = argparse.ArgumentParser(description="Solid Edge Occurrence-Replacer")
    parser.add_argument("--in", dest="input_dir", required=False, help="Path to .par files (Standard: INPUT env or ./input)")
    parser.add_argument("--out", dest="output_dir", required=False, help="Optional target-directory for .asm files (Standard: ./work)")
    
    if len(sys.argv) == 2 and sys.argv[1] in ("-h", "--help"):
        parser.print_help()
        sys.exit(0)

    args = parser.parse_args()

    # Umgebungsvariablen & Ordner
    work_dir = os.environ.get("PROJECT_WORK", "../work")
    data_dir = os.environ.get("PROJECT_DATA", "../data")

    if args.input_dir:
        input_dir = args.input_dir
        print("Using provided input directory.")  
    else: 
        input_dir = os.environ.get("PROJECT_INPUT", "../input")
        print("No input directory provided. Using standard input directory.")
    
    if args.output_dir:
        output_dir = args.output_dir
    else:
        output_dir = work_dir

    os.makedirs(work_dir, exist_ok=True)
    os.makedirs(output_dir, exist_ok=True)

    dummy_asm_path = os.path.join(data_dir, "dummy.asm")
    placeholder_name = "dummy.par"

    documents = start_solid_edge()

    par_dateien = [f for f in os.listdir(input_dir) if f.lower().endswith(".par")]

    if not par_dateien:
        print("No .par-files found in input-directory. Exiting...")
        exit(1)

    for par_name in par_dateien:
        par_path = os.path.join(input_dir, par_name)
        process_part(par_name, par_path, dummy_asm_path, placeholder_name, work_dir, output_dir, documents)

    if output_dir == work_dir:
        print("\nNo output folder (--out) specified. Files saved into 'work' folder.")
    else:
        print("\nAll .par files processed and saved into given target folder.")