#!/bin/bash
# DisplayHUB Controller Installer — writes installation.json where server.js expects it
set -euo pipefail

REMOTE_BASE="${REMOTE_BASE:-https://displayhub.us/clients/api/install-controller-roku}"
PRODUCT_NAME="${PRODUCT_NAME:-DisplayHUB}"
API_BASE_URL="${API_BASE_URL:-https://displayhub.us/clients/api}"
ORIGINAL_USER=${SUDO_USER:-$(logname 2>/dev/null || echo "pi")}

RED='\033[0;31m'; GREEN='\033[0;32m'; YELLOW='\033[1;33m'; NC='\033[0m'
log(){ echo -e "${GREEN}[$(date +'%H:%M:%S')]${NC} $*"; }
warn(){ echo -e "${YELLOW}[WARN]${NC} $*"; }
err(){ echo -e "${RED}[ERROR]${NC} $*"; exit 1; }
[ "$EUID" -eq 0 ] || err "Run as root (sudo)."

echo; echo "   ${PRODUCT_NAME} Controller Installer"; echo

mkdir -p /tmp; chattr -i /tmp 2>/dev/null || true; chown root:root /tmp || true; chmod 1777 /tmp || true

log "Installing prerequisites..."
apt-get update -qq 2>&1 | grep -v "^Reading" || true
DEBIAN_FRONTEND=noninteractive apt-get install -y -qq curl jq ca-certificates unzip avahi-daemon avahi-utils libcap2-bin || true

id -u displayhub >/dev/null 2>&1 || useradd -r -s /usr/sbin/nologin -d /nonexistent displayhub || true

if ! command -v node >/dev/null 2>&1 || ! command -v npm >/dev/null 2>&1; then
  log "Installing Node.js (v18)..."
  curl -fsSL https://deb.nodesource.com/setup_18.x | bash -
  DEBIAN_FRONTEND=noninteractive apt-get install -y -qq nodejs || err "Failed to install Node.js"
fi

INSTALL_DIR="/opt/displayhub-controller"
APP_DIR="$INSTALL_DIR/app"
LOG_DIR="/var/log/displayhub-controller"
ETC_DIR="/etc/displayhub-controller"
UNIT="/etc/systemd/system/displayhub-controller.service"

log "Preparing filesystem layout..."
mkdir -p "$INSTALL_DIR" "$APP_DIR" "$LOG_DIR" "$ETC_DIR" "$APP_DIR/config" "/etc/displayhub"
touch "$LOG_DIR/server.log" "$LOG_DIR/error.log"
chown -R displayhub:displayhub "$INSTALL_DIR" "$LOG_DIR" "$ETC_DIR" 2>/dev/null || true
chmod 755 "$INSTALL_DIR" || true; chmod 664 "$LOG_DIR/"*.log || true

REMOTE_VERSION="$(curl -fsSL "${REMOTE_BASE}/version.txt" | tr -d '\r\n' || echo "1.0.0-controller")"
DEVICE_ID="$(grep -m1 -i '^Serial' /proc/cpuinfo 2>/dev/null | awk '{print $3}' | sha256sum | awk '{print $1}' | cut -c1-16 || echo unknown)"
IP_ADDR="$(hostname -I 2>/dev/null | awk '{print $1}' || echo 127.0.0.1)"
ROKU_APP_ID="${ROKU_APP_ID:-dev}"

PRODUCT_SLUG="$(echo "$PRODUCT_NAME" | tr '[:upper:]' '[:lower:]' | sed 's/[^a-z0-9]/-/g; s/-\+/-/g; s/^-//; s/-$//' | cut -c1-63)"
[ -z "$PRODUCT_SLUG" ] && PRODUCT_SLUG="displayhub"
DESIRED_HOST="$PRODUCT_SLUG"

CUR_HOST="$(hostnamectl --static 2>/dev/null || hostname)"
if [ "$DESIRED_HOST" != "$CUR_HOST" ]; then
  log "Setting hostname -> ${DESIRED_HOST}"
  hostnamectl set-hostname "$DESIRED_HOST" || err "Failed to set hostname"
  if grep -qE '^127\.0\.1\.1\s' /etc/hosts; then
    sed -i "s/^127\.0\.1\.1.*/127.0.1.1\t${DESIRED_HOST}/" /etc/hosts
  else
    echo -e "127.0.1.1\t${DESIRED_HOST}" >> /etc/hosts
  fi
  systemctl enable avahi-daemon >/dev/null 2>&1 || true
  systemctl restart avahi-daemon || true
fi

log "Fetching manifest (files.json)..."
MAN="$(mktemp)"
# Always append a timestamp to bypass CDN / curl caching
curl -fsSL "${REMOTE_BASE}/files.json?d=$(date +%s)" -o "$MAN" || err "Couldn't download files.json"

install_one() {
  local src="$1" dest="$2" mode="$3" owner="$4" group="$5"
  mkdir -p "$(dirname "$dest")"
  local tmp="$(mktemp)"
  local bust="$(date +%s)"
  local sep='?'
  [[ "$src" == *'?'* ]] && sep='&'
  # Ensure each fetch is unique even if multiple files share name
  curl -fsSL "${REMOTE_BASE}/${src}${sep}d=${bust}" -o "$tmp" || err "Failed to fetch ${src}"
  install -m "$mode" -o "$owner" -g "$group" "$tmp" "$dest"
}

log "Stopping controller (if running)..."
systemctl stop displayhub-controller.service 2>/dev/null || true

# Clean out any stale public copies so browser never serves old bundle
rm -rf "$APP_DIR/public" "$APP_DIR/public_old" "$APP_DIR/public-backup" 2>/dev/null || true

log "Syncing files from server..."
len=$(jq 'length' "$MAN")
for ((i=0; i<len; i++)); do
  src=$(jq -r ".[$i].src" "$MAN")
  dest=$(jq -r ".[$i].dest" "$MAN")
  mode=$(jq -r ".[$i].mode" "$MAN")
  owner=$(jq -r ".[$i].owner" "$MAN")
  group=$(jq -r ".[$i].group" "$MAN")
  install_one "$src" "$dest" "$mode" "$owner" "$group"
done

[ -f "$APP_DIR/server.js" ] || err "server.js missing in $APP_DIR"

if [ -f "$APP_DIR/package.json" ]; then
  log "Installing Node dependencies..."
  # Prefer reproducible install if lockfile exists
  (cd "$APP_DIR" && npm ci --only=production >/dev/null 2>&1) || (cd "$APP_DIR" && npm install --only=prod)

  # Ensure axios/xml2js are present even if package.json didn’t include them
  (cd "$APP_DIR" && npm ls axios   >/dev/null 2>&1) || (cd "$APP_DIR" && npm install --no-save axios)
  (cd "$APP_DIR" && npm ls xml2js  >/dev/null 2>&1) || (cd "$APP_DIR" && npm install --no-save xml2js)

  chown -R displayhub:displayhub "$APP_DIR" || true
fi

HTTP_PORT=80
if ! setcap 'cap_net_bind_service=+ep' /usr/bin/node 2>/dev/null; then
  warn "setcap failed; using port 3000"
  HTTP_PORT=3000
fi

# WRITE THE FILES server.js EXPECTS (installation.json)
CFG_ETC_ROKU="/etc/displayhub/installation.json"
CFG_LOCAL_INSTALL="$APP_DIR/config/installation.json"
CONFIG_PAYLOAD="$(cat <<JSON
{
  "product_name": "${PRODUCT_NAME}",
  "version": "${REMOTE_VERSION}",
  "deviceId": "${DEVICE_ID}",
  "ipAddress": "${IP_ADDR}",
  "ports": { "http": ${HTTP_PORT}, "timeServer": 8888, "api": 3000 },
  "api_base_url": "${API_BASE_URL}",
  "discovery": { "roku": { "appId": "${ROKU_APP_ID}" } }
}
JSON
)"

log "Writing ${CFG_ETC_ROKU}"
echo "${CONFIG_PAYLOAD}" > "$CFG_ETC_ROKU"
chown displayhub:displayhub "$CFG_ETC_ROKU" || true
chmod 664 "$CFG_ETC_ROKU" || true

log "Writing ${CFG_LOCAL_INSTALL}"
echo "${CONFIG_PAYLOAD}" > "$CFG_LOCAL_INSTALL"
chown displayhub:displayhub "$CFG_LOCAL_INSTALL" || true
chmod 664 "$CFG_LOCAL_INSTALL" || true

# Unit with preflight check for installation.json at either location
UNIT="/etc/systemd/system/displayhub-controller.service"
cat > "$UNIT" <<EOF
[Unit]
Description=DisplayHUB Controller (Node.js)
After=network-online.target
Wants=network-online.target

[Service]
Type=simple
User=displayhub
Group=displayhub
WorkingDirectory=$APP_DIR
Environment=NODE_ENV=production
ExecStartPre=/usr/bin/test -r $CFG_ETC_ROKU -o -r $CFG_LOCAL_INSTALL
ExecStart=/usr/bin/node server.js
Restart=on-failure
RestartSec=2
LimitNOFILE=65536
StandardOutput=journal
StandardError=journal

[Install]
WantedBy=multi-user.target
EOF

chmod 644 "$UNIT"
systemctl daemon-reload

log "Enabling and starting controller..."
systemctl enable displayhub-controller.service >/dev/null
systemctl restart displayhub-controller.service || true
sleep 2

log "Health check..."
if ! systemctl is-active --quiet displayhub-controller.service; then
  journalctl -u displayhub-controller -n 120 --no-pager || true
  err "Service failed to start."
fi

URL="http://127.0.0.1:${HTTP_PORT}/"
if ! curl -fsS --max-time 4 "$URL" >/dev/null; then
  journalctl -u displayhub-controller -n 120 --no-pager || true
  err "HTTP probe failed at ${URL}"
fi

# ---------------------------------------------
# Compute local access URL
# ---------------------------------------------
LOCAL_IP="$(hostname -I 2>/dev/null | awk '{print $1}')"
HOSTNAME_URL="$(hostnamectl --static 2>/dev/null || hostname)"
if [[ -n "$HOSTNAME_URL" ]]; then
    # Prefer mDNS-style .local hostname if available
    URL="http://${HOSTNAME_URL}.local/"
else
    URL="http://${LOCAL_IP:-127.0.0.1}/"
fi

echo
echo "========================================="
echo " Installation Complete"
echo "========================================="
echo " Product:   $PRODUCT_NAME Controller"
echo " Version:   $REMOTE_VERSION"
echo " Hostname:  $(hostnamectl --static 2>/dev/null || hostname)"
echo " Web UI:    ${URL}"
echo "========================================="
echo