"""
Comprehensive SSL/TLS security scanning and analysis.
All blocking socket calls run in a thread pool; user input is sanitised.
Output is a clean code block with aligned columns.
"""

import asyncio
import logging
import socket
import ssl
import OpenSSL
import datetime
import simplematrixbotlib as botlib
from plugins.common import is_public_destination, html_escape, collapsible_summary, code_block

# SSL/TLS configuration – handle missing protocols in modern Python
TLS_VERSIONS = {
    'TLSv1.2': ssl.PROTOCOL_TLSv1_2,
    'TLSv1.3': ssl.PROTOCOL_TLS
}
try:
    TLS_VERSIONS['TLSv1.1'] = ssl.PROTOCOL_TLSv1_1
except AttributeError:
    pass
try:
    TLS_VERSIONS['TLSv1'] = ssl.PROTOCOL_TLSv1
except AttributeError:
    pass

CIPHER_CATEGORIES = {
    'STRONG': [
        'TLS_AES_256_GCM_SHA384', 'TLS_CHACHA20_POLY1305_SHA256',
        'TLS_AES_128_GCM_SHA256', 'ECDHE-RSA-AES256-GCM-SHA384',
        'ECDHE-ECDSA-AES256-GCM-SHA384', 'ECDHE-RSA-CHACHA20-POLY1305',
        'ECDHE-ECDSA-CHACHA20-POLY1305', 'DHE-RSA-AES256-GCM-SHA384'
    ],
    'WEAK': ['RC4', 'DES', '3DES', 'MD5', 'EXPORT', 'NULL', 'ANON', 'ADH', 'CBC'],
}

async def handle_command(room, message, bot, prefix, config):
    match = botlib.MessageMatch(room, message, bot, prefix)
    if match.is_not_from_this_bot() and match.prefix() and match.command("sslscan"):
        args = match.args()
        if len(args) < 1:
            await show_usage(room, bot)
            return

        target = args[0].strip()
        port = 443
        if ':' in target:
            parts = target.split(':')
            target = parts[0]
            try:
                port = int(parts[1])
            except ValueError:
                await bot.api.send_text_message(room.room_id, "Invalid port number")
                return

        if not is_public_destination(target):
            await bot.api.send_text_message(room.room_id, "❌ Scanning of private/internal addresses is not allowed.")
            return

        await perform_ssl_scan(room, bot, target, port)

async def show_usage(room, bot):
    usage = """<strong>🔐 SSL/TLS Security Scanner</strong>
<strong>!sslscan &lt;domain[:port]&gt;</strong> - Comprehensive SSL/TLS security analysis

<strong>Examples:</strong>
• <code>!sslscan example.com</code>
• <code>!sslscan github.com:443</code>

<strong>Tests Performed:</strong>
• SSL/TLS protocol support and versions
• Certificate chain validation and expiration
• Cipher suite strength and configuration
• Security headers and extensions
• Handshake simulation and vulnerabilities
• PCI DSS compliance checking
• SSL/TLS best practices assessment
"""
    await bot.api.send_markdown_message(room.room_id, usage)

async def _run_blocking(func, *args, **kwargs):
    loop = asyncio.get_running_loop()
    return await loop.run_in_executor(None, lambda: func(*args, **kwargs))

def _test_connectivity(target, port):
    try:
        with socket.create_connection((target, port), timeout=10):
            return True
    except:
        return False

def _get_certificate_info(target, port):
    context = ssl.create_default_context()
    context.check_hostname = False
    context.verify_mode = ssl.CERT_NONE
    with socket.create_connection((target, port), timeout=10) as sock:
        with context.wrap_socket(sock, server_hostname=target) as ssock:
            cert_bin = ssock.getpeercert(binary_form=True)
            cert = OpenSSL.crypto.load_certificate(OpenSSL.crypto.FILETYPE_ASN1, cert_bin)

            subject = cert.get_subject()
            issuer = cert.get_issuer()
            not_before = cert.get_notBefore().decode('utf-8')
            not_after = cert.get_notAfter().decode('utf-8')
            sig_alg = cert.get_signature_algorithm().decode('utf-8')
            not_after_dt = datetime.datetime.strptime(not_after, '%Y%m%d%H%M%SZ')
            days_remaining = (not_after_dt - datetime.datetime.utcnow()).days

            extensions = []
            for i in range(cert.get_extension_count()):
                ext = cert.get_extension(i)
                extensions.append({
                    'name': ext.get_short_name().decode('utf-8'),
                    'value': str(ext)
                })

            return {
                'subject': {
                    'common_name': subject.CN,
                    'organization': subject.O,
                    'organizational_unit': subject.OU,
                    'country': subject.C,
                    'state': subject.ST,
                    'locality': subject.L
                },
                'issuer': {
                    'common_name': issuer.CN,
                    'organization': issuer.O,
                    'organizational_unit': issuer.OU
                },
                'serial_number': cert.get_serial_number(),
                'version': cert.get_version(),
                'not_before': not_before,
                'not_after': not_after,
                'signature_algorithm': sig_alg,
                'days_until_expiry': days_remaining,
                'extensions': extensions
            }
    return None

def _test_protocols(target, port):
    protocols = {}
    for proto_name in ['SSLv2', 'SSLv3', 'TLSv1', 'TLSv1.1', 'TLSv1.2', 'TLSv1.3']:
        if proto_name not in TLS_VERSIONS:
            protocols[proto_name] = False
            continue
        try:
            ctx = ssl.SSLContext(TLS_VERSIONS[proto_name])
            ctx.check_hostname = False
            ctx.verify_mode = ssl.CERT_NONE
            with socket.create_connection((target, port), timeout=5) as sock:
                with ctx.wrap_socket(sock, server_hostname=target):
                    protocols[proto_name] = True
        except:
            protocols[proto_name] = False
    return protocols

def _test_cipher_suites(target, port):
    test_ciphers = [
        'ECDHE-RSA-AES256-GCM-SHA384', 'ECDHE-ECDSA-AES256-GCM-SHA384',
        'ECDHE-RSA-AES256-SHA384', 'ECDHE-ECDSA-AES256-SHA384',
        'ECDHE-RSA-AES256-SHA', 'ECDHE-ECDSA-AES256-SHA',
        'AES256-GCM-SHA384', 'AES256-SHA256', 'AES256-SHA',
        'CAMELLIA256-SHA', 'PSK-AES256-CBC-SHA',
        'ECDHE-RSA-AES128-GCM-SHA256', 'ECDHE-ECDSA-AES128-GCM-SHA256',
        'ECDHE-RSA-AES128-SHA256', 'ECDHE-ECDSA-AES128-SHA256',
        'ECDHE-RSA-AES128-SHA', 'ECDHE-ECDSA-AES128-SHA',
        'AES128-GCM-SHA256', 'AES128-SHA256', 'AES128-SHA',
        'CAMELLIA128-SHA', 'PSK-AES128-CBC-SHA',
        'DES-CBC3-SHA', 'RC4-SHA', 'RC4-MD5'
    ]
    supported = []
    for cipher in test_ciphers:
        try:
            ctx = ssl.create_default_context()
            ctx.check_hostname = False
            ctx.verify_mode = ssl.CERT_NONE
            ctx.set_ciphers(cipher)
            with socket.create_connection((target, port), timeout=5) as sock:
                with ctx.wrap_socket(sock, server_hostname=target):
                    supported.append(cipher)
        except:
            pass
    return supported

def _check_vulnerabilities(protocols, cert_info, supported_ciphers):
    vulns = []
    if protocols.get('SSLv2'):
        vulns.append(('SSLv2 Support', 'CRITICAL'))
    if protocols.get('SSLv3'):
        vulns.append(('SSLv3 Support', 'HIGH'))
    if cert_info and cert_info.get('days_until_expiry', 0) < 30:
        vulns.append(('Certificate Expiring Soon', 'MEDIUM'))
    weak_ciphers = [c for c in supported_ciphers if any(w in c.upper() for w in CIPHER_CATEGORIES['WEAK'])]
    if weak_ciphers:
        vulns.append(('Weak Cipher Suites', 'HIGH'))
    if not protocols.get('TLSv1.2', False):
        vulns.append(('TLS 1.2 Not Supported', 'HIGH'))
    if not protocols.get('TLSv1.3', False):
        vulns.append(('TLS 1.3 Not Supported', 'MEDIUM'))
    return vulns

def _calculate_score(protocols, cert_info, supported_ciphers, vulnerabilities):
    score = 100
    if protocols.get('SSLv2'): score -= 30
    if protocols.get('SSLv3'): score -= 20
    if not protocols.get('TLSv1.2'): score -= 15
    if not protocols.get('TLSv1.3'): score -= 10
    if cert_info and cert_info.get('days_until_expiry', 0) < 30: score -= 10
    if cert_info and cert_info.get('days_until_expiry', 0) < 7: score -= 20
    weak_cipher_count = sum(1 for c in supported_ciphers if any(w in c.upper() for w in CIPHER_CATEGORIES['WEAK']))
    score -= min(weak_cipher_count * 5, 25)
    for name, severity in vulnerabilities:
        if severity == 'CRITICAL': score -= 20
        elif severity == 'HIGH': score -= 15
        elif severity == 'MEDIUM': score -= 10
    return max(0, score)

def _generate_recommendations(protocols, cert_info, supported_ciphers, score):
    recs = []
    if protocols.get('SSLv2'): recs.append("🔴 Disable SSLv2")
    if protocols.get('SSLv3'): recs.append("🔴 Disable SSLv3")
    if not protocols.get('TLSv1.3'): recs.append("🟡 Enable TLSv1.3")
    if cert_info and cert_info.get('days_until_expiry', 0) < 30:
        recs.append("🟡 Renew certificate")
    weak_ciphers = [c for c in supported_ciphers if any(w in c.upper() for w in CIPHER_CATEGORIES['WEAK'])]
    if weak_ciphers:
        recs.append("🔴 Remove weak ciphers")
    if score < 80:
        recs.append("🛡️ Improve TLS configuration")
    if not any('ECDHE' in c for c in supported_ciphers):
        recs.append("🟡 Enable Forward Secrecy")
    return recs

async def perform_ssl_scan(room, bot, target, port):
    safe_target = html_escape(target)
    await bot.api.send_text_message(room.room_id, f"🔍 Starting SSL/TLS scan for {safe_target}:{port}...")

    if not await _run_blocking(_test_connectivity, target, port):
        await bot.api.send_text_message(room.room_id, f"❌ Cannot connect to {safe_target}:{port}")
        return

    cert_task = _run_blocking(_get_certificate_info, target, port)
    proto_task = _run_blocking(_test_protocols, target, port)
    cipher_task = _run_blocking(_test_cipher_suites, target, port)

    cert_info, protocols, supported_ciphers = await asyncio.gather(cert_task, proto_task, cipher_task)

    vulnerabilities = _check_vulnerabilities(protocols, cert_info, supported_ciphers)
    score = _calculate_score(protocols, cert_info, supported_ciphers, vulnerabilities)
    recommendations = _generate_recommendations(protocols, cert_info, supported_ciphers, score)

    sections = []

    # Score
    score_emoji = "🟢" if score >= 90 else "🟡" if score >= 80 else "🟠" if score >= 60 else "🔴"
    rating = "Excellent" if score >= 90 else "Good" if score >= 80 else "Fair" if score >= 60 else "Poor"
    sections.append({"title": f"{score_emoji} Security Score", "rows": [("", "Score", f"{score}/100 ({rating})")]})

    # Certificate
    if cert_info:
        cert_rows = [
            ("📜", "Subject", cert_info['subject'].get('common_name', 'N/A')),
            ("🏢", "Issuer", cert_info['issuer'].get('common_name', 'N/A')),
            ("📅", "Valid Until", cert_info['not_after']),
            ("⏳", "Expires In", f"{cert_info['days_until_expiry']} days"),
        ]
        sections.append({"title": "📜 Certificate", "rows": cert_rows})

    # Protocols
    proto_rows = []
    for proto in ['SSLv2', 'SSLv3', 'TLSv1', 'TLSv1.1', 'TLSv1.2', 'TLSv1.3']:
        supported = protocols.get(proto, False)
        if proto in ['SSLv2', 'SSLv3'] and supported:
            emoji = "🔴"
        elif proto == 'TLSv1.3' and supported:
            emoji = "✅"
        else:
            emoji = "✅" if supported else "❌"
        status = "Supported" if supported else "Not Supported"
        if proto in ['SSLv2', 'SSLv3'] and proto not in TLS_VERSIONS:
            status = "Cannot test"
            emoji = "⚫"
        proto_rows.append((emoji, proto, status))
    sections.append({"title": "🔌 Protocols", "rows": proto_rows})

    # Cipher Suites
    weak_ciphers = [c for c in supported_ciphers if any(w in c.upper() for w in CIPHER_CATEGORIES['WEAK'])]
    strong_ciphers = [c for c in supported_ciphers if any(s in c.upper() for s in CIPHER_CATEGORIES['STRONG'])]
    cipher_rows = [("🔢", "Total Supported", str(len(supported_ciphers)))]
    if weak_ciphers:
        cipher_rows.append(("🔴", "Weak Ciphers", str(len(weak_ciphers))))
        for c in weak_ciphers[:3]:
            cipher_rows.append(("", "", c))
    if strong_ciphers:
        cipher_rows.append(("🟢", "Strong Ciphers", str(len(strong_ciphers))))
    sections.append({"title": "🔐 Cipher Suites", "rows": cipher_rows})

    # Vulnerabilities
    if vulnerabilities:
        vuln_rows = []
        for name, sev in vulnerabilities:
            sev_emoji = "🔴" if sev == 'CRITICAL' else "🟠" if sev == 'HIGH' else "🟡"
            vuln_rows.append((sev_emoji, name, sev))
        sections.append({"title": "⚠️ Vulnerabilities", "rows": vuln_rows})

    # Recommendations
    if recommendations:
        rec_rows = [("💡", "Recommendation", rec) for rec in recommendations]
        sections.append({"title": "💡 Recommendations", "rows": rec_rows})

    # Quick Assessment
    assessment_rows = []
    if score >= 90:
        assessment_rows = [("", "Assessment", "✅ Excellent configuration")]
    elif score >= 70:
        assessment_rows = [("", "Assessment", "⚠️ Good, minor improvements possible")]
    else:
        assessment_rows = [("", "Assessment", "🚨 Significant issues found")]
    sections.append({"title": "📊 Quick Assessment", "rows": assessment_rows})

    block = code_block(f"🔐 SSL/TLS Scan: {safe_target}:{port}", sections)
    output = collapsible_summary(f"🔐 SSL/TLS: {safe_target} (Score: {score}/100)", block)
    await bot.api.send_markdown_message(room.room_id, output)
    logging.info(f"Completed SSL scan for {target}:{port}")

# ---------------------------------------------------------------------------
# Plugin Metadata
# ---------------------------------------------------------------------------
__version__ = "1.0.2"
__author__ = "Funguy Bot"
__description__ = "SSL/TLS security scanner"
__help__ = """
<details>
<summary><strong>!sslscan</strong> – SSL/TLS analysis</summary>
<p><code>!sslscan &lt;domain[:port]&gt;</code> – Tests protocols, cipher suites, certificate validity, vulnerabilities.<br>
Provides a security score (0-100) and actionable recommendations.</p>
</details>
"""