#!/usr/bin/env bash
set -euo pipefail

# Obermon Agent Installer
# Usage: curl -sL https://get.obermon.com | bash -s -- --key=YOUR_KEY

BASE_URL="https://get.obermon.com"
INSTALL_DIR="/usr/local/bin"
BINARY="obermon-agent"
SERVICE="obermon-agent"

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

log()  { echo -e "${GREEN}[obermon]${NC} $1"; }
warn() { echo -e "${YELLOW}[obermon]${NC} $1"; }
err()  { echo -e "${RED}[obermon]${NC} $1" >&2; exit 1; }

# ─── Parse arguments ──────────────────────────────────────────
AGENT_KEY=""
HUB="https://hub.obermon.com"

while [[ $# -gt 0 ]]; do
    case $1 in
        --key=*) AGENT_KEY="${1#*=}" ;;
        --hub=*) HUB="${1#*=}" ;;
        *) warn "Unknown option: $1" ;;
    esac
    shift
done

[ -z "$AGENT_KEY" ] && err "Missing --key. Get your key from the Obermon dashboard."

# ─── Detect platform ─────────────────────────────────────────
OS=$(uname -s | tr '[:upper:]' '[:lower:]')
ARCH=$(uname -m)
case "$ARCH" in
    x86_64)  ARCH="amd64" ;;
    aarch64|arm64) ARCH="arm64" ;;
    *) err "Unsupported architecture: $ARCH" ;;
esac
[ "$OS" != "linux" ] && err "This installer supports Linux only. On macOS use: go run ./cmd/agent"

FILE="${BINARY}-${OS}-${ARCH}"

log ""
log "Installing Obermon Agent..."
log "  Platform: ${OS}/${ARCH}"
log "  Hub:      ${HUB}"
log "  Key:      ${AGENT_KEY:0:12}..."
log ""

# ─── Download binary ─────────────────────────────────────────
log "Downloading ${FILE}..."
curl -fsSL "${BASE_URL}/${FILE}" -o "/tmp/${BINARY}" || err "Download failed. Is get.obermon.com reachable?"
chmod +x "/tmp/${BINARY}"
sudo mv "/tmp/${BINARY}" "${INSTALL_DIR}/${BINARY}"
log "Binary installed to ${INSTALL_DIR}/${BINARY}"

# ─── Create systemd service ───────────────────────────────────
log "Configuring systemd service..."
sudo tee /etc/systemd/system/${SERVICE}.service > /dev/null << EOF
[Unit]
Description=Obermon Monitoring Agent
After=network-online.target
Wants=network-online.target

[Service]
Type=simple
ExecStart=${INSTALL_DIR}/${BINARY}
Restart=always
RestartSec=5
Environment=OBERMON_KEY=${AGENT_KEY}
Environment=OBERMON_HUB=${HUB}

[Install]
WantedBy=multi-user.target
EOF

sudo systemctl stop ${SERVICE} 2>/dev/null || true
sudo systemctl daemon-reload
sudo systemctl enable ${SERVICE}
sudo systemctl start ${SERVICE}

# ─── Verify ───────────────────────────────────────────────────
sleep 2
if systemctl is-active --quiet ${SERVICE}; then
    log ""
    log "✅ Obermon Agent installed and running!"
    log ""
    log "  Status:  sudo systemctl status ${SERVICE}"
    log "  Logs:    sudo journalctl -u ${SERVICE} -f"
    log "  Stop:    sudo systemctl stop ${SERVICE}"
    log "  Remove:  sudo systemctl disable ${SERVICE} && sudo rm ${INSTALL_DIR}/${BINARY}"
    log ""
    log "Your server should appear in the dashboard within 30 seconds."
else
    err "Agent installed but failed to start. Check: sudo journalctl -u ${SERVICE} -e"
fi