import os
from dotenv import load_dotenv
import discord
from discord import app_commands
import requests
import dns.resolver
import markdownify
import subprocess
import tempfile
import re
import binascii
from cryptography import x509
from cryptography.hazmat.backends import default_backend
import datetime
from apscheduler.schedulers.asyncio import AsyncIOScheduler



load_dotenv()
TOKEN = os.getenv('DISCORD_TOKEN')
ADMINID = 0
KUTT_APIKEY=os.getenv('LINK_API_KEY')
KUTT_URL=os.getenv('LINK_URL')
LOG_CHANNEL = int(os.getenv('LOG_CHANNEL'))

intents = discord.Intents.default()
client = discord.Client(intents=intents)
tree = app_commands.CommandTree(client)
activityMessage="over the server"
statusType="watching"


# Commands
@tree.command(name="ping", description="Check bot connection")
async def ping(ctx):
    await ctx.response.send_message("Pong!",ephemeral=True)

@tree.command(name="shortlink", description="Shorten a link")
async def shortlink(ctx, link: str, name: str = None):
    if (ctx.user.id != ADMINID):
        await log("User: " + str(ctx.user.name) + " tried to use the shortlink command")
        await ctx.response.send_message("You don't have permission to use this command",ephemeral=True)
    else:
        url=f"{KUTT_URL}/api/v2/links"
        headers = {'X-API-KEY' : KUTT_APIKEY}

        data = {'target' : link, 'customurl' : name}
        if (name == None):
            data = {'target' : link}    
        x = requests.post(url, data = data, headers = headers)
        if (x.status_code != 200 and x.status_code != 201):
            await ctx.response.send_message("ERROR: " + x.text,ephemeral=True)
        link=x.json()['link']
        await ctx.response.send_message("Link: " + link,ephemeral=False)

@tree.command(name="botstatus", description="Set the bot status")
async def botstatus(ctx, message: str, statusmethod: str = None):
    if (ctx.user.id != ADMINID):
        await log("User: " + str(ctx.user.name) + " tried to use the botstatus command")
        await ctx.response.send_message("You don't have permission to use this command",ephemeral=True)
    else:
        global activityMessage
        activityMessage=message
        global statusType
        if (statusmethod == None):
            statusmethod="watching"
        else:
            statusType=statusmethod.lower()
        updateStatus()
        await ctx.response.send_message("Status updated",ephemeral=True)

@tree.command(name="dig", description="Dig a dns record")
async def dig(ctx, domain: str, record_type: str = "A"):
    record_type = record_type.upper()
    resolver = dns.resolver.Resolver()
    resolver.nameservers = ["100.74.29.146"]
    resolver.port = 53
    try:
        # Query the DNS record
        response = resolver.resolve(domain, record_type)
        records = ""
        for record in response:
            records = records + "\n" + str(record)

        # Send the result to the Discord channel
        await ctx.response.send_message(f"DNS records for {domain} ({record_type}):{records}")

    except dns.resolver.NXDOMAIN:
        await ctx.response.send_message(f"Domain {domain} not found.")
    except dns.exception.DNSException as e:
        await ctx.response.send_message(f"An error occurred: {e}")

@tree.command(name="curl", description="HTTP request")
async def curl(ctx, url: str):
    try:
        proxyURL = "https://proxy.hnsproxy.au"
        response = requests.get(url, proxies={"http": proxyURL, "https": proxyURL},verify=False)
        output = response.text
        # Get BODY only
        output = output.split("<body")[1]
        output = output.split("</body>")[0]
        output = output.split(">", 1)[1]
        # Replace any relative links with absolute links
        output = output.replace('href="/', 'href="' + url + '/')
        parsed = markdownify.markdownify(output, heading_style="ATX")
        # Delete any empty lines
        parsed = "\n".join([s for s in parsed.splitlines() if s.strip()])

        output = response.text
        # Get title
        if (output.find("<title>") != -1):
            title = output.split("<title>")[1]
            title = title.split("</title>")[0]
        else:
            title = url
        if (len(parsed) > 4096):
            parsed = parsed[:4096]
            # Delete any incomplete lines
            parsed = "\n".join(parsed.splitlines()[:-1])
            parsed = parsed + "\n..."

        # if url is a tld only replace it with the url https://hns.au (due to Discord not allowing tld only links)
        if (url.find(".") == -1):
            url = "https://hns.au"
        # Create an embed
        embed = discord.Embed(title=title, url=url, description=parsed)
        embed.set_footer(text="Parsed by HNSProxy",icon_url="https://hns.au/assets/img/favicon.png")
        embed.timestamp = discord.utils.utcnow()
        await ctx.response.send_message(embed=embed)
    except requests.exceptions.RequestException as e:
        await ctx.response.send_message(f"An error occurred: {e}")
    except Exception as e:
        await ctx.response.send_message(f"An error occurred: {e}")

@tree.command(name="ssl", description="Check SSL certificate")
async def ssl(ctx, domain: str, showcert: bool = False, notifymeonexpiry: bool = False):
    # Verify that the domain is valid
    if not domain:
        await ctx.response.send_message("Please provide a domain to check")
        return
    
    regexmatch = re.match(r"^([a-z0-9]+(-[a-z0-9]+)*\.)*([a-z0-9]+(-[a-z0-9]+)*)$", domain)
    if not regexmatch:
        await ctx.response.send_message("Please provide a valid domain to check")
        return

    await ctx.response.send_message(f"Checking SSL certificate for {domain}...")
    message = ""
    resolver = dns.resolver.Resolver()
    resolver.nameservers = ["100.74.29.146"]
    resolver.port = 53
    domain_check = False
    try:
        # Query the DNS record
        response = resolver.resolve(domain, "A")
        records = []
        message = "## A records:\n"
        for record in response:
            records.append(str(record))
            message = message + "- " +str(record) + "\n"


        if not records:
            await ctx.channel.send(f"No A record found for {domain}")
            return
        
        # Get the first A record
        ip = records[0]
        
        # Run the openssl s_client command
        s_client_command = ["openssl","s_client","-showcerts","-connect",f"{ip}:443","-servername",domain,]

        s_client_process = subprocess.Popen(s_client_command, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
        s_client_output, _ = s_client_process.communicate(input=b"\n")
        
        certificates = []
        current_cert = ""
        for line in s_client_output.split(b"\n"):
            current_cert += line.decode("utf-8") + "\n"
            if "-----END CERTIFICATE-----" in line.decode("utf-8"):
                certificates.append(current_cert)
                current_cert = ""

        # Remove anything before -----BEGIN CERTIFICATE-----
        certificates = [cert[cert.find("-----BEGIN CERTIFICATE-----"):] for cert in certificates]

        if certificates:
            cert = certificates[0]
            if showcert:
                message = message + "\n## Website Certificate:\n```\n" + cert + "\n```\n"

            with tempfile.NamedTemporaryFile(mode="w", delete=False) as temp_cert_file:
                temp_cert_file.write(cert)
                temp_cert_file.seek(0)  # Move back to the beginning of the temporary file

            tlsa_command = ["openssl","x509","-in",temp_cert_file.name,"-pubkey","-noout","|","openssl","pkey","-pubin","-outform","der","|","openssl","dgst","-sha256","-binary",]
            
            tlsa_process = subprocess.Popen(" ".join(tlsa_command), shell=True, stdout=subprocess.PIPE)
            tlsa_output, _ = tlsa_process.communicate()

            tlsa_server = "3 1 1 " + binascii.hexlify(tlsa_output).decode("utf-8")

            
            message = message + "\n## TLSA Record from webserver:\n`" + tlsa_server + "`\n"


            # Get domains
            cert_obj = x509.load_pem_x509_certificate(cert.encode("utf-8"), default_backend())

            domains = []
            for ext in cert_obj.extensions:
                if ext.oid == x509.ExtensionOID.SUBJECT_ALTERNATIVE_NAME:
                    san_list = ext.value.get_values_for_type(x509.DNSName)
                    domains.extend(san_list)
            
            # Extract the common name (CN) from the subject
            common_name = cert_obj.subject.get_attributes_for_oid(x509.NameOID.COMMON_NAME)
            if common_name:
                if common_name[0].value not in domains:
                    domains.append(common_name[0].value)


            if domains:
                message = message + "\n## SSL Domains:\n"
                for cn in domains:
                    message = message + "- " + cn + "\n"
                if domain in domains:
                    domain_check = True

            expiry_date = cert_obj.not_valid_after
            # Check if expiry date is past
            if expiry_date < datetime.datetime.now():
                message = message + "\n## Expiry Date:\n:x: Certificate has expired\n"
            elif expiry_date < datetime.datetime.now() + datetime.timedelta(days=7):
                message = message + "\n## Expiry Date:\n:warning: Certificate expires soon\n"
            else:
                message = message + "\n## Expiry Date:\n:white_check_mark: Certificate is valid\n"

            message = message + expiry_date.strftime("%d %B %Y %H:%M:%S") + "\n"


        else:
            message = message + "\n## Website Certificate:\n:x: No certificate found\n"
            message = message + "\n## TLSA Record from webserver:\n:x: No certificate found\n"

        try:
            # Check for TLSA record
            response = resolver.resolve("_443._tcp."+domain, "TLSA")
            tlsa_records = []
            message = message + "\n## TLSA Records from DNS:\n"
            for record in response:
                tlsa_records.append(str(record))
                message = message + "- " +str(record) + "\n"

            if not tlsa_records:
                message = message + "\n## Result:\n:x: No TLSA record found\n"
            else:
                if tlsa_server == tlsa_records[0]:
                    if domain_check:
                        message = message + "\n## Result:\n:white_check_mark: TLSA record matches certificate\n"
                    else:
                        message = message + "\n## Result:\n:x: TLSA record matches certificate but domain does not match\n"
                
                else:
                    message = message + "\n## Result:\n:x: TLSA record does not match certificate\n"
        
        except:
            message = message + "\n## TLSA Records from DNS:\n:x: No TLSA record found\n"
            message = message + "\n## Result:\n:x: No TLSA record found\n"


        # If message is too long, send it in 2 messages
        if (len(message) > 2000):
            # Split on the last line under 2000 characters
            message1 = message[:2000]
            message1 = message1[:message1.rfind("\n")]
            message2 = message[len(message1):]
                            
            
            await ctx.channel.send(message1)
            await ctx.channel.send(message2)
            
            
        else:
            await ctx.channel.send(message)

        if (notifymeonexpiry):
            with open("/mnt/sslnotify.txt", "a") as file:
                file.write(str(ctx.user.id) + "," + domain + "\n")
            
    # Catch all exceptions
    except Exception as e:
        await ctx.channel.send(f"An error occurred: {e}")

    
@tree.command(name="invite", description="Invite me to your server")
async def invite(ctx):
    await ctx.response.send_message("https://discord.com/api/oauth2/authorize?client_id=1006128164218621972&permissions=0&scope=bot",ephemeral=True)

async def log(message):
    channel=client.get_channel(LOG_CHANNEL)
    await channel.send(message)

def updateStatus():
    global activityMessage
    global statusType
    if (statusType == "watching"):
        activity=discord.Activity(type=discord.ActivityType.watching, name=activityMessage)
    elif (statusType == "playing"):
        activity=discord.Activity(type=discord.ActivityType.playing, name=activityMessage)
    elif (statusType == "listening"):
        activity=discord.Activity(type=discord.ActivityType.listening, name=activityMessage)
    elif (statusType == "competing"):
        activity=discord.Activity(type=discord.ActivityType.competing, name=activityMessage)
    else:
        activity=discord.Activity(type=discord.ActivityType.watching, name=activityMessage)
    client.loop.create_task(client.change_presence(activity=activity))

async def checkForSSLExpiry():
    with open("/mnt/sslnotify.txt", "r") as file:
        lines = file.readlines()
        for line in lines:
            line = line.strip()
            if not line:
                print("No line", flush=True)
                continue
            userid, domain = line.split(",")
            print(f"Checking SSL certificate for {domain}...", flush=True)
            resolver = dns.resolver.Resolver()
            resolver.nameservers = ["100.74.29.146"]
            resolver.port = 53
            try:
                # Query the DNS record
                response = resolver.resolve(domain, "A")
                records = []
                for record in response:
                    records.append(str(record))
                if not records:
                    print(f"No A record found for {domain}", flush=True)
                    continue
                # Get the first A record
                ip = records[0]
                # Run the openssl s_client command
                s_client_command = ["openssl","s_client","-showcerts","-connect",f"{ip}:443","-servername",domain,]
                s_client_process = subprocess.Popen(s_client_command, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
                s_client_output, _ = s_client_process.communicate(input=b"\n")
                certificates = []
                current_cert = ""
                for line in s_client_output.split(b"\n"):
                    current_cert += line.decode("utf-8") + "\n"
                    if "-----END CERTIFICATE-----" in line.decode("utf-8"):
                        certificates.append(current_cert)
                        current_cert = ""
                # Remove anything before -----BEGIN CERTIFICATE-----
                certificates = [cert[cert.find("-----BEGIN CERTIFICATE-----"):] for cert in certificates]
                if certificates:
                    cert = certificates[0]
                    # Get expiry date
                    cert_obj = x509.load_pem_x509_certificate(cert.encode("utf-8"), default_backend())
                    expiry_date = cert_obj.not_valid_after
                    if expiry_date < datetime.datetime.now() + datetime.timedelta(days=7):
                        user = client.fetch_user(int(userid))
                        if user:
                            await user.send(f"SSL certificate for {domain} expires soon")
                            print(f"SSL certificate for {domain} expires soon", flush=True)
                        else:
                            print(f"User {userid} not found", flush=True)
                    else:
                        # Test by sending a message
                        user = client.fetch_user(int(userid))
                        if user:
                            await user.send(f"SSL certificate for {domain} is valid")
                            print(f"SSL certificate for {domain} is valid", flush=True)
                        else:
                            print(f"User {userid} not found", flush=True)
                else:
                    print(f"No certificate found for {domain}", flush=True)
                    await user.send(f"No certificate found for {domain}")
                    continue
            except Exception as e:
                print(e, flush=True)
                log(e)
                continue
    print("SSL check complete", flush=True)

    

@tree.command(name="ssldomains", description="List domains with SSL certificates")
async def ssldomains(ctx):
    # Get user id
    userid = str(ctx.user.id)
    # Get all domains for user
    domains = []
    with open("/mnt/sslnotify.txt", "r") as file:
        lines = file.readlines()
        for line in lines:
            line = line.strip()
            if not line:
                continue
            if line.startswith(userid):
                _, domain = line.split(",")
                domains.append(domain)
    if not domains:
        await ctx.response.send_message("You have no domains in the SSL expiry notification list",ephemeral=True)
        return
    
    await ctx.response.send_message("Domains in the SSL expiry notification list:\n" + "\n".join(domains),ephemeral=True)


@tree.command(name="sslremove", description="Remove a domain from the SSL expiry notification list")
async def sslremove(ctx, domain: str):
    # Get user id
    userid = str(ctx.user.id)
    # Get all domains for user
    domains = []
    with open("/mnt/sslnotify.txt", "r") as file:
        lines = file.readlines()
        for line in lines:
            line = line.strip()
            if not line:
                continue
            if line.startswith(userid):
                _, dom = line.split(",")
                domains.append(dom)
    if not domains:
        await ctx.response.send_message("You have no domains in the SSL expiry notification list",ephemeral=True)
        return
    
    if domain not in domains:
        await ctx.response.send_message("Domain not found in the SSL expiry notification list",ephemeral=True)
        return
    
    with open("/mnt/sslnotify.txt", "w") as file:
        for line in lines:
            line = line.strip()
            if not line:
                continue
            if not line.startswith(userid):
                file.write(line + "\n")
        for dom in domains:
            if domain != dom:
                file.write(userid + "," + dom + "\n")
    
    await ctx.response.send_message("Domain removed from the SSL expiry notification list",ephemeral=True)


@tree.command(name="manualsslcheck", description="Manually check SSL certificate")
async def manualsslcheck(ctx):
    if (ctx.user.id != ADMINID):
        await log("User: " + str(ctx.user.name) + " tried to use the manualsslcheck command")
        await ctx.response.send_message("You don't have permission to use this command",ephemeral=True)

    await ctx.response.send_message("SSL checking",ephemeral=True)
    await checkForSSLExpiry()
    await ctx.channel.send("SSL check complete",ephemeral=True)
    

# When the bot is ready
@client.event
async def on_ready():
    global ADMINID
    ADMINID = client.application.owner.id
    await tree.sync()
    updateStatus()
    await checkForSSLExpiry()


# Every 12 hours check for SSL expiry
scheduler = AsyncIOScheduler()
scheduler.add_job(checkForSSLExpiry, 'interval', hours=12)
scheduler.start()

client.run(TOKEN)