#!/bin/bash

set -euo pipefail

DOMAIN=$1
if [ -z ${DOMAIN} ]; then
    echo "Script usage: ./install.sh <DOMAIN>"
    return 1
fi

BASE_DIR=/opt/matrix

# Create directory and copy configs + docker-compose YAML
mkdir -p ${BASE_DIR}/db
cp -R . ${BASE_DIR}
cd ${BASE_DIR}

# Disable "Pending Kernel upgrade" banner
sed -i "s|#\$nrconf{kernelhints} = -1;|\$nrconf{kernelhints} = -1;|g" /etc/needrestart/needrestart.conf

# Disable "Daemon Using Outdated Libraries" banner
sed -i "s|#\$nrconf{restart} = 'i';|\$nrconf{restart} = 'a';|g" /etc/needrestart/needrestart.conf

# Baseline utils
echo -e "Installing baseline utils\n"
apt update
apt upgrade -y
apt install -y ca-certificates curl pwgen nginx python3-certbot-nginx ufw coturn

# Open only needed ports
echo -e "Opening ports and enabling ufw\n"
# SSH
ufw allow 22/tcp

# Nginx (HTTP/HTTPS)
ufw allow 80/tcp        
ufw allow 443/tcp
ufw allow 8448/tcp

# Coturn Ports
ufw allow 3478/udp
ufw allow 5443/udp
ufw allow 49152:65535/udp

# Enable firewall
ufw --force enable

# Configure Coturn TURN server
echo -e "Install and configure coturn server\n"

echo "TURNSERVER_ENABLED=1" > /etc/default/coturn
cp config/turnserver.conf /etc/

TURN_PWD=$(pwgen -s 28 -1)
TURN_STATIC_SECRET=$(pwgen -s 64 1)
EXTERNAL_IP=$(curl -s checkip.amazonaws.com)

sed -i "s|DOMAIN|${DOMAIN}|g" /etc/turnserver.conf
sed -i "s|TURN_PWD|${TURN_PWD}|g" /etc/turnserver.conf
sed -i "s|EXTERNAL_IP|${EXTERNAL_IP}|g" /etc/turnserver.conf
sed -i "s|STATIC_SECRET|${TURN_STATIC_SECRET}|g" /etc/turnserver.conf

# Custom coturn SystemD service file to allow coturn access to Letsencrypt SSL certs
cp "${BASE_DIR}/coturn.service" /lib/systemd/system/coturn.service
systemctl daemon-reload

# Add Docker's official GPG key
echo -e "Install docker\n"

install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to APT sources
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "${VERSION_CODENAME}") stable" | \
  tee /etc/apt/sources.list.d/docker.list > /dev/null
apt update

# Install docker
apt install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

# Create docker network `matrix_server`
echo -e "Create docker network\n"

docker network create --driver=bridge --subnet=10.10.10.0/24 --gateway=10.10.10.1 matrix_server

# Randomly pick a DB password
PG_PASS=$(pwgen -s 28 -1)

# Replace PG_PASS Password and DOMAIN in docker compose YAML
sed -i "s|DOMAIN|${DOMAIN}|g" "${BASE_DIR}/docker-compose.yaml"
sed -i "s|PG_PASS|${PG_PASS}|g" "${BASE_DIR}/docker-compose.yaml"

# Generate synapse file
echo -e "Generating synapse file..\n"
docker compose run --rm -e SYNAPSE_SERVER_NAME=${DOMAIN} -e SYNAPSE_REPORT_STATS=yes synapse generate

# Replace DB config in Synapse's homeserver.yaml
echo -e "Configuring homeserver.yaml\n"

# Granting all read permissions to cert files
chmod 444 ${BASE_DIR}/config/synapse/${DOMAIN}.*

# Config homeserver.yaml
sed -i '$ d' "${BASE_DIR}/config/synapse/homeserver.yaml"
sed -e '22r homeserver.yaml.db' -e '22,25d' "${BASE_DIR}/config/synapse/homeserver.yaml" > /tmp/homeserver.yaml
cp /tmp/homeserver.yaml "${BASE_DIR}/config/synapse/homeserver.yaml"

# Configure User Directory and TURN
cat <<EOF >> "${BASE_DIR}/config/synapse/homeserver.yaml"
user_directory:
    enabled: true
    search_all_users: true
    prefer_local_users: true
    show_locked_users: true
turn_allow_guests: False
turn_user_lifetime: 86400000
turn_shared_secret: "${TURN_STATIC_SECRET}"
turn_uris: [ "turn:${DOMAIN}?transport=udp" ]
suppress_key_server_warning: true
EOF

# Replace Password in homeserver.yaml
sed -i "s|PG_PASS|${PG_PASS}|g" "${BASE_DIR}/config/synapse/homeserver.yaml"

# Replace Sliding Sync key
SLIDING_SYNC_KEY=$(openssl rand -hex 32)
sed -i "s|SLIDING_SYNC_KEY|${SLIDING_SYNC_KEY}|g" "${BASE_DIR}/docker-compose.yaml"

# Replace domain in element config
sed -i "s|DOMAIN|${DOMAIN}|g" "${BASE_DIR}/config/element/element-config.json"

# Copy SystemD file and start the service
echo -e "Setting up SystemD service\n"

cp "${BASE_DIR}/matrix.service" /etc/systemd/system/
systemctl daemon-reload
systemctl enable --now matrix.service

# Configure Nginx
echo -e "Configuring nginx\n"

cat <<EOF > /etc/nginx/sites-enabled/default
server {
    listen 80;
    server_name ${DOMAIN};

    location /.well-known/matrix/client {
        default_type application/json;
        add_header Access-Control-Allow-Origin *;
        return 200 '{"m.homeserver": {"base_url": "https://${DOMAIN}"}, "org.matrix.msc3575.proxy": {"url": "https://${DOMAIN}"}}';
    }

    # Admin panel
    location /admin/ {
        proxy_pass http://10.10.10.6/;
        proxy_set_header X-Forwarded-For \$remote_addr;
        proxy_set_header X-Forwarded-Proto \$scheme;
        proxy_set_header Host \$host;
        proxy_http_version 1.1;
    }

    # Sydent identity server
    location ~ ^(/_matrix/identity) {
        proxy_pass http://10.10.10.5:8090;
        proxy_set_header X-Forwarded-For \$remote_addr;
        proxy_set_header X-Forwarded-Proto \$scheme;
        proxy_set_header Host \$host;
        proxy_http_version 1.1;
    }

    # Sliding Sync
    location ~ ^/(client/|_matrix/client/unstable/org.matrix.msc3575/sync) {
        proxy_pass http://10.10.10.7:8008;
        proxy_set_header X-Forwarded-For \$remote_addr;
        proxy_set_header X-Forwarded-Proto \$scheme;
        proxy_set_header Host \$host;
    }

    # Synapse Backend
    location ~ ^(\/_matrix|\/_synapse\/(client|admin)) {
        # Synapse Container Network IP
        proxy_pass http://10.10.10.4:8008;
        proxy_set_header X-Forwarded-For \$remote_addr;
        proxy_set_header X-Forwarded-Proto \$scheme;
        proxy_set_header Host \$host;
        client_max_body_size 50M;
        proxy_http_version 1.1;
    }

    # Element Frontend
    location / {
        # Element chat Container Network IP
        proxy_pass http://10.10.10.3;
        proxy_set_header X-Forwarded-For \$remote_addr;
        proxy_set_header X-Forwarded-Proto \$scheme;
        proxy_set_header Host \$host;

        # Nginx by default only allows file uploads up to 1M in size
        # Increase client_max_body_size to match max_upload_size defined in homeserver.yaml
        client_max_body_size 50M;
 
        # Synapse responses may be chunked, which is an HTTP/1.1 feature.
        proxy_http_version 1.1;
    }
}
EOF

systemctl restart nginx
systemctl enable --now nginx

echo -e "Generate SSL cert\n"
certbot --nginx -d ${DOMAIN} --agree-tos --register-unsafely-without-email

# Add certbot SSL cert renewal to crontab
crontab -l | { cat; echo '43 6 * * * certbot renew --post-hook "systemctl reload nginx"'; } | crontab -

# Add custom 8448 SSL port for Matrix Federation
sed -i '/listen\ 443\ ssl/a\\tlisten\ 8448\ ssl\;' /etc/nginx/sites-enabled/default
nginx -s reload

# Enable coturn
systemctl enable --now coturn

# Finally, start services
# Ensuring the DB dir is clean before bootstrapping
systemctl enable --now matrix.service