main.py

"""DevCheck: a command-line developer environment checker.

DevCheck scans a computer for common development tools, reports whether each
one is installed and which version it is, and can export or compare scan
results. It never installs, uninstalls, modifies, or updates any software -
it only inspects the system.

Run with:
    python main.py
"""

from pathlib import Path
from typing import Dict, Optional, Tuple

from checker import EnvironmentChecker
from config import DATA_DIR_NAME, REPORTS_DIR_NAME, SCAN_HISTORY_FILENAME
from history import compare_scans, load_scan, print_comparison, save_scan
from reports import build_report, export_to_csv, export_to_json, print_scan_table
from utils import ensure_directory, get_project_root

PROJECT_ROOT = get_project_root()
DATA_DIR = PROJECT_ROOT / DATA_DIR_NAME
REPORTS_DIR = PROJECT_ROOT / REPORTS_DIR_NAME
HISTORY_PATH = DATA_DIR / SCAN_HISTORY_FILENAME


def run_full_scan(checker: EnvironmentChecker) -> Tuple[Optional[Dict], Dict]:
    """Run a full scan, print it, save it to history, and return (old, new) reports.

    The report on disk *before* this scan is returned as "old" so the caller
    can immediately compare it against the fresh "new" report, in addition to
    it being available for comparisons in future runs of the program.
    """
    previous_report = load_scan(HISTORY_PATH)

    results = checker.scan_all()
    current_report = build_report(results)

    print()
    print_scan_table(results)

    ensure_directory(DATA_DIR)
    save_scan(current_report, HISTORY_PATH)

    return previous_report, current_report


def run_single_tool_check(checker: EnvironmentChecker) -> None:
    """Prompt for a tool name and print its individual check result."""
    print()
    print("Available tools:")
    for index, name in enumerate(checker.list_tool_names(), start=1):
        print(f"  {index}. {name}")

    choice = input("\nEnter the tool name to check: ").strip()
    if not choice:
        print("No tool name entered.")
        return

    result = checker.check_tool_by_name(choice)
    if result is None:
        print(f"'{choice}' is not in the list of known tools.")
        return

    print()
    print(f"Tool:    {result.name}")
    print(f"Status:  {result.status.value}")
    print(f"Version: {result.version if result.version else '-'}")
    print(f"Path:    {result.path if result.path else '-'}")
    if result.error:
        print(f"Note:    {result.error}")


def view_previous_scan() -> None:
    """Print the most recently saved scan from disk, if one exists."""
    report = load_scan(HISTORY_PATH)
    if report is None:
        print("\nNo previous scan found. Run a full scan first (option 1).")
        return

    print()
    print(f"Last scan timestamp: {report.get('timestamp', 'Unknown')}")
    print(f"Operating system:    {report.get('operating_system', 'Unknown')}")
    print()
    print(f"{'Tool':<18}{'Status':<32}{'Version'}")
    for entry in report.get("results", []):
        print(f"{entry['tool']:<18}{entry['status']:<32}{entry['version']}")


def compare_with_previous(previous_report: Optional[Dict], current_report: Optional[Dict]) -> None:
    """Compare the two most recent reports and print the differences."""
    if current_report is None:
        print("\nRun a full scan first (option 1), then use this option to compare.")
        return
    if previous_report is None:
        print("\nThis looks like the first scan on record. Run another scan later to compare.")
        return

    print()
    print_comparison(compare_scans(previous_report, current_report))


def export_report(checker: EnvironmentChecker) -> None:
    """Run a fresh scan and export it to JSON, CSV, or both."""
    results = checker.scan_all()
    report = build_report(results)
    ensure_directory(REPORTS_DIR)

    print("\nExport format:")
    print("  1. JSON")
    print("  2. CSV")
    print("  3. Both")
    choice = input("Choose an option: ").strip()

    if choice not in ("1", "2", "3"):
        print("Invalid choice. No report exported.")
        return

    if choice in ("1", "3"):
        json_path = REPORTS_DIR / "scan_report.json"
        export_to_json(report, json_path)
        print(f"JSON report saved to: {json_path}")
    if choice in ("2", "3"):
        csv_path = REPORTS_DIR / "scan_report.csv"
        export_to_csv(report, csv_path)
        print(f"CSV report saved to: {csv_path}")


def print_menu() -> None:
    """Print the main DevCheck menu."""
    print()
    print("=" * 32)
    print("DEVCHECK")
    print("=" * 8)
    print()
    print("1. Full Environment Scan")
    print("2. Check a Specific Tool")
    print("3. View Previous Scan")
    print("4. Compare Scans")
    print("5. Export Report")
    print("6. Exit")
    print()


def main() -> None:
    """Run the interactive DevCheck menu loop."""
    checker = EnvironmentChecker()
    previous_report: Optional[Dict] = None
    current_report: Optional[Dict] = None

    while True:
        print_menu()
        choice = input("Choose an option: ").strip()

        if choice == "1":
            previous_report, current_report = run_full_scan(checker)
        elif choice == "2":
            run_single_tool_check(checker)
        elif choice == "3":
            view_previous_scan()
        elif choice == "4":
            compare_with_previous(previous_report, current_report)
        elif choice == "5":
            export_report(checker)
        elif choice == "6":
            print("\nExiting DevCheck. Goodbye!")
            break
        else:
            print("\nInvalid option. Please choose a number between 1 and 6.")


if __name__ == "__main__":
    main()