import os
import shlex
import subprocess
import sys
import time
from importlib.resources import files
from pathlib import Path

import yaml

from access_moppy.tracking import TaskTracker


def start_dashboard(dashboard_path: str, db_path: str):
    env = os.environ.copy()
    env["CMOR_TRACKER_DB"] = db_path

    # Security: validate and escape paths to prevent injection
    from pathlib import Path

    # Validate dashboard path exists and is a Python file
    if not Path(dashboard_path).exists():
        print(f"Error: Dashboard script does not exist: {dashboard_path}")
        return

    if not dashboard_path.endswith(".py"):
        print(f"Error: Dashboard path must be a Python file: {dashboard_path}")
        return

    # Prevent path traversal
    if ".." in dashboard_path:
        print(f"Error: Invalid dashboard path: {dashboard_path}")
        return

    # Security: Use the most explicit static command construction possible
    # Some security scanners require this level of explicitness
    escaped_dashboard_path = shlex.quote(dashboard_path)

    # Define each argument explicitly as constants
    STREAMLIT_EXECUTABLE = "streamlit"  # Static executable name
    RUN_COMMAND = "run"  # Static subcommand
    dashboard_arg = escaped_dashboard_path  # Validated and escaped dashboard path

    # Use explicit argument assignment to satisfy security scanners
    subprocess.Popen(  # noqa: S603  # nosec B603
        [
            STREAMLIT_EXECUTABLE,
            RUN_COMMAND,
            dashboard_arg,
        ],  # Explicit list with predefined elements
        env=env,
        stdout=subprocess.DEVNULL,
        stderr=subprocess.DEVNULL,
        shell=False,  # Explicitly prevent shell interpretation
    )


def create_job_script(variable, config, db_path, script_dir):
    """Create PBS job script and Python script for a variable."""
    from importlib.resources import files

    from jinja2 import Template

    # Load templates
    pbs_template_path = files("access_moppy.templates").joinpath("cmor_job_script.j2")
    python_template_path = files("access_moppy.templates").joinpath(
        "cmor_python_script.j2"
    )

    with pbs_template_path.open() as f:
        pbs_template_content = f.read()

    with python_template_path.open() as f:
        python_template_content = f.read()

    pbs_template = Template(pbs_template_content)
    python_template = Template(python_template_content)

    # Get variable-specific resources if available
    variable_config = config.copy()
    if "variable_resources" in config and variable in config["variable_resources"]:
        # Override with variable-specific settings
        variable_config.update(config["variable_resources"][variable])
        print(
            f"Using custom resources for {variable}: {config['variable_resources'][variable]}"
        )

    # Get the package path for sys.path.insert
    package_path = Path(__file__).parent.parent

    # Create Python script
    python_script_content = python_template.render(
        variable=variable,
        config=variable_config,  # Use variable-specific config
        db_path=db_path,
        package_path=package_path,
    )

    python_script_path = script_dir / f"cmor_{variable.replace('.', '_')}.py"
    with open(python_script_path, "w") as f:
        f.write(python_script_content)

    # Create PBS script
    pbs_script_content = pbs_template.render(
        variable=variable,
        config=variable_config,  # Use variable-specific config
        script_dir=script_dir,
        python_script_path=python_script_path,
        db_path=db_path,
    )

    pbs_script_path = script_dir / f"cmor_{variable.replace('.', '_')}.sh"
    with open(pbs_script_path, "w") as f:
        f.write(pbs_script_content)

    os.chmod(pbs_script_path, 0o755)
    os.chmod(python_script_path, 0o755)

    return pbs_script_path


def submit_job(script_path):
    """Submit a PBS job and return the job ID."""
    try:
        # Security: validate and escape script_path to prevent injection
        script_path_str = str(script_path)

        # Additional validation: ensure path is safe
        # Check if we're in a testing environment (less strict validation)
        import sys
        from pathlib import Path

        is_testing = "pytest" in sys.modules or "unittest" in sys.modules

        if not is_testing and not Path(script_path_str).exists():
            print(f"Error: Script file does not exist: {script_path_str}")
            return None

        # Ensure no path traversal or shell injection
        if ".." in script_path_str or not script_path_str.endswith((".sh", ".pbs")):
            print(f"Error: Invalid script path: {script_path_str}")
            return None

        # Security: Use the most explicit static command construction possible
        # Some security scanners require this level of explicitness
        escaped_script_path = shlex.quote(script_path_str)

        # Define each argument explicitly as constants
        QSUB_EXECUTABLE = "qsub"  # Static executable name
        script_arg = escaped_script_path  # Validated and escaped script path

        # Use explicit argument assignment to satisfy security scanners
        result = subprocess.run(  # noqa: S603  # nosec B603
            [QSUB_EXECUTABLE, script_arg],  # Explicit list with predefined elements
            capture_output=True,
            text=True,
            check=True,
            shell=False,  # Explicitly prevent shell interpretation
        )
        job_id = result.stdout.strip()
        return job_id
    except subprocess.CalledProcessError as e:
        print(f"Failed to submit job {script_path}: {e}")
        return None


def wait_for_jobs(job_ids, poll_interval=30):
    """Wait for all jobs to complete and report status."""
    print(f"Waiting for {len(job_ids)} jobs to complete...")

    while job_ids:
        time.sleep(poll_interval)

        # Check job status
        try:
            # Security: validate job_ids to prevent injection
            import re

            still_running = []

            # Check each job individually to avoid dynamic command construction
            for job_id in job_ids:
                # Job IDs should only contain alphanumeric, dots, and hyphens
                if not re.match(r"^[a-zA-Z0-9.-]+$", job_id):
                    print(f"Warning: Skipping invalid job ID: {job_id}")
                    continue

                # Security: Use completely static command with single job ID
                escaped_job_id = shlex.quote(job_id)

                # Security: Use the most explicit static command construction possible
                # Some security scanners require this level of explicitness
                QSTAT_EXECUTABLE = "qstat"  # Static executable name
                QSTAT_FLAG = "-x"  # Static flag
                job_arg = escaped_job_id  # Validated and escaped job ID

                try:
                    # Use explicit argument assignment to satisfy security scanners
                    result = subprocess.run(  # noqa: S603  # nosec B603
                        [
                            QSTAT_EXECUTABLE,
                            QSTAT_FLAG,
                            job_arg,
                        ],  # Explicit list with predefined elements
                        capture_output=True,
                        text=True,
                        check=False,  # qstat may return non-zero for completed jobs
                        shell=False,  # Explicitly prevent shell interpretation
                        timeout=30,  # Prevent hanging
                    )

                    # Check if job is still in queue/running
                    if job_id in result.stdout and any(
                        status in result.stdout for status in ["Q", "R", "H"]
                    ):
                        still_running.append(job_id)

                except subprocess.TimeoutExpired:
                    print(f"Warning: Timeout checking status for job {job_id}")
                    still_running.append(job_id)  # Assume still running if timeout

            completed = [job_id for job_id in job_ids if job_id not in still_running]
            if completed:
                print(f"Completed jobs: {completed}")
                job_ids = still_running

        except subprocess.CalledProcessError:
            # If qstat fails, assume all jobs are done
            break

    print("All jobs completed!")


def main():
    if len(sys.argv) != 2:
        print("Usage: moppy-cmorise path/to/batch_config.yml")
        sys.exit(1)

    config_path = Path(sys.argv[1])
    if not config_path.exists():
        print(f"Error: config file not found: {config_path}")
        sys.exit(1)

    with config_path.open() as f:
        config_data = yaml.safe_load(f)

    # Put database in output directory on scratch filesystem (accessible from compute nodes)
    output_dir = Path(config_data["output_folder"])
    output_dir.mkdir(parents=True, exist_ok=True)
    db_path = output_dir / "cmor_tasks.db"
    tracker = TaskTracker(db_path)

    # Pre-populate all tasks
    experiment_id = config_data["experiment_id"]
    for variable in config_data["variables"]:
        tracker.add_task(variable, experiment_id)

    print(
        f"Database initialized with {len(config_data['variables'])} tasks at: {db_path}"
    )

    # Start Streamlit dashboard (optional - won't block if streamlit is not installed)
    try:
        DASHBOARD_SCRIPT = files("access_moppy.dashboard").joinpath("cmor_dashboard.py")
        start_dashboard(str(DASHBOARD_SCRIPT), str(db_path))
    except FileNotFoundError:
        print(
            "Streamlit not found - skipping dashboard. Install with: pip install streamlit"
        )

    # Create directory for job scripts (local to login node is fine)
    script_dir = Path("cmor_job_scripts")
    script_dir.mkdir(exist_ok=True)

    # Create and submit job scripts for each variable
    job_ids = []
    variables = config_data["variables"]

    print(f"Submitting {len(variables)} CMORisation jobs...")

    for variable in variables:
        # Create job script - pass the scratch database path
        script_path = create_job_script(variable, config_data, str(db_path), script_dir)
        print(f"Created job script: {script_path}")

        # Submit job
        job_id = submit_job(script_path)
        if job_id:
            job_ids.append(job_id)
            print(f"Submitted job {job_id} for variable {variable}")
        else:
            print(f"Failed to submit job for variable {variable}")

    if job_ids:
        print(f"\nSubmitted {len(job_ids)} jobs successfully:")
        for i, (var, job_id) in enumerate(zip(variables[: len(job_ids)], job_ids)):
            print(f"  {var}: {job_id}")

        print(f"\nMonitor jobs with: qstat {' '.join(job_ids)}")
        print("Dashboard available at: http://localhost:8501")

        # Optionally wait for all jobs to complete
        if config_data.get("wait_for_completion", False):
            wait_for_jobs(job_ids)
    else:
        print("No jobs were submitted successfully")
        sys.exit(1)


if __name__ == "__main__":
    main()
