#!/usr/bin/env python3
"""
patch_diff.py — Download and diff Business Directory Plugin
    v6.4.21 (vulnerable) vs v6.4.22 (patched)

Pinpoints the exact lines changed to fix CVE-2026-2576
Requires: svn OR wget/curl (falls back to direct zip download)
"""

import os
import sys
import subprocess
import shutil
import difflib
import urllib.request
import zipfile
import io
from pathlib import Path

try:
    from colorama import Fore, Style, init
    init(autoreset=True)
except ImportError:
    class Fore:
        RED=GREEN=YELLOW=CYAN=WHITE=BLUE=""
    class Style:
        RESET_ALL=""

VULNERABLE = "6.4.21"
PATCHED    = "6.4.22" 
SLUG       = "business-directory-plugin"

# WordPress.org SVN
SVN_BASE  = f"https://plugins.svn.wordpress.org/{SLUG}/tags"
# WordPress.org direct zip
ZIP_BASE  = f"https://downloads.wordpress.org/plugin/{SLUG}"

# Files most likely to contain the fix, in priority order
TARGET_FILES = [
    "includes/class-db-query-set.php",
    "views/class-checkout.php",
    "core/class-payment.php",
    "includes/helpers/class-payment-query.php",
    "app/models/class-payment.php",
]

WORK_DIR = Path("/tmp/wpbdp_diff")


# Try to download using SVN first (faster if available), 
# otherwise fall back to direct zip download
def download_zip(version: str) -> Path:
    dest = WORK_DIR / version
    if dest.exists():
        print(f"  {Fore.CYAN}[cache]{Style.RESET_ALL} Using cached {version}")
        return dest

    url = f"{ZIP_BASE}.{version}.zip"
    print(f"  {Fore.BLUE}[dl]{Style.RESET_ALL} Downloading {url} ...")
    try:
        with urllib.request.urlopen(url, timeout=30) as resp:
            data = resp.read()
        zf = zipfile.ZipFile(io.BytesIO(data))
        zf.extractall(WORK_DIR)
        # Zip extracts to e.g. business-directory-plugin/
        extracted = WORK_DIR / SLUG
        if extracted.exists():
            extracted.rename(dest)
        else:
            # Some zips use version-suffixed folder
            for item in WORK_DIR.iterdir():
                if item.is_dir() and SLUG in item.name:
                    item.rename(dest)
                    break
        print(f"  {Fore.GREEN}[ok]{Style.RESET_ALL} Extracted to {dest}")
        return dest
    except Exception as e:
        print(f"  {Fore.RED}[!]{Style.RESET_ALL} Download failed: {e}")
        return None

# Note: SVN export is faster and cleaner than downloading and extracting zips,
# but it requires SVN to be installed and may be blocked in some environments.
# This function is not used in the main flow but can be enabled if desired.
def diff_file(path_a: Path, path_b: Path) -> list:
    """Return unified diff lines between two files."""
    try:
        lines_a = path_a.read_text(errors="replace").splitlines(keepends=True)
        lines_b = path_b.read_text(errors="replace").splitlines(keepends=True)
    except FileNotFoundError:
        return []
    return list(difflib.unified_diff(
        lines_a, lines_b,
        fromfile=str(path_a),
        tofile=str(path_b),
        lineterm="",
    ))

# Simple color-coding for diff output
def color_diff(lines: list) -> str:
    out = []
    for line in lines:
        if line.startswith("+++") or line.startswith("---"):
            out.append(f"{Fore.WHITE}{line}{Style.RESET_ALL}")
        elif line.startswith("+"):
            out.append(f"{Fore.GREEN}{line}{Style.RESET_ALL}")
        elif line.startswith("-"):
            out.append(f"{Fore.RED}{line}{Style.RESET_ALL}")
        elif line.startswith("@@"):
            out.append(f"{Fore.CYAN}{line}{Style.RESET_ALL}")
        else:
            out.append(line)
    return "\n".join(out)

# Recursively find all PHP files in a directory, returning relative paths
def find_all_php(root: Path) -> list:
    return sorted(root.rglob("*.php"))

# Main execution flow
def main():
    print(f"""
    {Fore.YELLOW}══════════════════════════════════════════════════════
    CVE-2026-2576 Patch Differ
    {SLUG}  {VULNERABLE} → {PATCHED}
    ══════════════════════════════════════════════════════{Style.RESET_ALL}
    """)

    WORK_DIR.mkdir(parents=True, exist_ok=True)

    print(f"{Fore.BLUE}[*]{Style.RESET_ALL} Downloading plugin versions...")
    dir_vuln   = download_zip(VULNERABLE)
    dir_patched = download_zip(PATCHED)

    if not dir_vuln or not dir_patched:
        print(f"{Fore.RED}[-]{Style.RESET_ALL} Failed to download one or both versions.")
        print("     Try manually:")
        print(f"     svn export {SVN_BASE}/{VULNERABLE}/ {WORK_DIR}/{VULNERABLE}/")
        print(f"     svn export {SVN_BASE}/{PATCHED}/ {WORK_DIR}/{PATCHED}/")
        sys.exit(1)

    # Targeted diff on known relevant files
    print(f"\n{Fore.YELLOW}[1] Diffing target files (most likely to contain fix):{Style.RESET_ALL}")
    found_diffs = []

    for rel in TARGET_FILES:
        fa = dir_vuln   / rel
        fb = dir_patched / rel
        if not fa.exists() and not fb.exists():
            continue
        diff = diff_file(fa, fb)
        if diff:
            print(f"\n{Fore.WHITE}{'═'*60}{Style.RESET_ALL}")
            print(f"{Fore.YELLOW}FILE: {rel}{Style.RESET_ALL}")
            print(f"{Fore.WHITE}{'═'*60}{Style.RESET_ALL}")
            print(color_diff(diff))
            found_diffs.append(rel)

    # Full scan: any changed PHP file
    print(f"\n{Fore.YELLOW}[2] Full scan — all changed PHP files:{Style.RESET_ALL}")
    all_vuln    = {f.relative_to(dir_vuln):    f for f in find_all_php(dir_vuln)}
    all_patched = {f.relative_to(dir_patched): f for f in find_all_php(dir_patched)}

    all_keys = set(all_vuln.keys()) | set(all_patched.keys())
    changed = []

    for rel in sorted(all_keys):
        fa = all_vuln.get(rel)
        fb = all_patched.get(rel)
        if fa is None:
            print(f"  {Fore.GREEN}[NEW]{Style.RESET_ALL} {rel}")
            changed.append(str(rel))
            continue
        if fb is None:
            print(f"  {Fore.RED}[DEL]{Style.RESET_ALL} {rel}")
            changed.append(str(rel))
            continue
        if fa.read_bytes() != fb.read_bytes():
            changed.append(str(rel))
            print(f"  {Fore.CYAN}[MOD]{Style.RESET_ALL} {rel}")

    print(f"\n{Fore.GREEN}[+]{Style.RESET_ALL} {len(changed)} file(s) changed between versions")

    # Print full diffs for all changed files
    if "--full" in sys.argv:
        print(f"\n{Fore.YELLOW}[3] Full diffs (--full mode):{Style.RESET_ALL}")
        for rel in sorted(all_keys):
            fa = all_vuln.get(rel)
            fb = all_patched.get(rel)
            if fa and fb:
                diff = diff_file(fa, fb)
                if diff:
                    print(f"\n{'═'*60}\nFILE: {rel}\n{'═'*60}")
                    print(color_diff(diff))

    # Summary and patterns to look for in the diffs
    print(f"""
{Fore.YELLOW}══════════════════════════════════════════════════════
    Diff Analysis Complete
══════════════════════════════════════════════════════{Style.RESET_ALL}

    Vulnerable version : {VULNERABLE}  →  {dir_vuln}
    Patched version    : {PATCHED}  →  {dir_patched}

    Files changed: {len(changed)}
    {chr(10).join('    ' + f for f in changed[:15])}

    Look for these patterns in the diff to find the fix:
    {Fore.GREEN}+  $wpdb->prepare(){Style.RESET_ALL}        <= parameterised query added
    {Fore.GREEN}+  absint(){Style.RESET_ALL}                <= integer sanitisation
    {Fore.GREEN}+  intval(){Style.RESET_ALL}                <= integer cast
    {Fore.GREEN}+  sanitize_text_field(){Style.RESET_ALL}   <= string sanitisation
    {Fore.RED}-  $payment_id{Style.RESET_ALL}               <= raw variable removed from query

    Re-run with --full to see complete diffs for all files.
""")

if __name__ == "__main__":
    main()