#!/usr/bin/env python3

import sys
import subprocess
import tempfile
import os

# Force temp files into a folder inside your project
custom_temp_dir = os.path.join(os.getcwd(), "tmp")
os.makedirs(custom_temp_dir, exist_ok=True)
tempfile.tempdir = custom_temp_dir

MVSHOST = "oldcomputernerd.com"
RDRPORT = 3505
MVS_PASSWORD = os.environ.get("MVS_BATCH_PASSWORD")


def create_delete_jcl(dataset_name, member_name):
    """Create JCL to delete a PDS member using IEHPROGM"""

    jcl = f"""
//DELETE   JOB (ACCT),'DELETE',
//             USER=@05054,PASSWORD={MVS_PASSWORD},
//             CLASS=A,MSGCLASS=H,NOTIFY=@05054
//DELMEM   EXEC PGM=IEHPROGM
//SYSPRINT DD SYSOUT=*
//DD1      DD DSN={dataset_name},DISP=SHR
//SYSIN    DD *
  DELETE DSNAME={dataset_name},MEMBER={member_name}
/*
"""
    return jcl


def delete_member(dataset_name, member_name, mvshost=MVSHOST):
    """Delete a member from MVS PDS"""

    payload = create_delete_jcl(dataset_name, member_name)

    # Write JCL to temporary file and submit via netcat
    with tempfile.NamedTemporaryFile(mode='w', delete=False, suffix='.jcl') as tmpfile:
        tmpfile.write(payload)
        tmpfile.flush()
        tmpfile_path = tmpfile.name

    try:
        with open(tmpfile_path, 'rb') as f:
            result = subprocess.run(
                ['nc', '-w', '5', mvshost, str(RDRPORT)],
                input=f.read(),
                check=True,
                capture_output=True
            )
        print(f"Deleted {dataset_name}({member_name})")
        if result.stdout:
            print("JES response:", result.stdout.decode(errors='ignore').strip())
        return 0
    except subprocess.CalledProcessError as e:
        print(f"Deletion failed: {e}")
        print("stderr:", e.stderr.decode(errors='ignore'))
        return 1
    finally:
        os.unlink(tmpfile_path)


if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: delete_mvs_member.py <pds_destination> [mvshost]")
        print()
        print("Arguments:")
        print("  pds_destination - PDS destination as DATASET(MEMBER) (required)")
        print("  mvshost        - MVS host (optional, default: oldcomputernerd.com)")
        print()
        print("Examples:")
        print("  delete_mvs_member.py '@05054.SRCLIB.C(SIEVE11)'")
        print("  delete_mvs_member.py '@05054.SRCLIB.C(HELLO)' mainframe.example.com")
        sys.exit(1)

    destination = sys.argv[1]

    # Parse PDS syntax: DATASET(MEMBER)
    if '(' in destination and destination.endswith(')'):
        dataset_name = destination[:destination.index('(')]
        member_name = destination[destination.index('(')+1:-1]
    else:
        print(f"Error: Invalid PDS syntax '{destination}'. Use format: DATASET(MEMBER)")
        sys.exit(1)

    # Optional host override
    mvshost = sys.argv[2] if len(sys.argv) > 2 else MVSHOST

    print(f"Deleting: {dataset_name}({member_name})")
    print(f"Host: {mvshost}")
    print()

    sys.exit(delete_member(dataset_name, member_name, mvshost))