#!/usr/bin/env bash
# ────────────────────────────────────────────────────────────────────
# DECT relay agent — data-center install / upgrade helper.
#
# Run this inside the unzipped bundle directory on the DC host. It:
#   1. Sanity-checks that Docker + Compose are installed.
#   2. Loads the shipped image tarball into the local Docker daemon.
#   3. Pins IMAGE_TAG in .env to whatever tag was baked into the
#      tarball (so compose can never fall back to a stale local
#      cache without you noticing).
#   4. Verifies .env exists and has the required keys populated.
#   5. Runs `docker compose up -d` and tails the last 40 lines.
#
# Safe to run repeatedly — it's a straightforward upgrade too:
#   unzip -o new-bundle.zip -d dect-relay-agent-bundle
#   cd dect-relay-agent-bundle
#   ./install.sh
# ────────────────────────────────────────────────────────────────────
set -euo pipefail

# Colors, only if stdout is a TTY. Corporate SSH sessions often are;
# CI / pipe-to-file are not.
if [[ -t 1 ]]; then
  BOLD=$'\033[1m'; DIM=$'\033[2m'; RED=$'\033[31m'; GREEN=$'\033[32m'
  YELLOW=$'\033[33m'; RESET=$'\033[0m'
else
  BOLD=''; DIM=''; RED=''; GREEN=''; YELLOW=''; RESET=''
fi

log() { echo "${BOLD}[install]${RESET} $*"; }
die() { echo "${RED}[install] ERROR:${RESET} $*" >&2; exit 1; }

# Ensure we're running from the bundle dir (compose file must be here).
cd "$(dirname "$0")"

# ─── 1. Preflight ──────────────────────────────────────────────────
log "Preflight checks"
command -v docker >/dev/null 2>&1 || die "docker is not installed or not on PATH"

# Compose v2 is `docker compose` (space); v1 is `docker-compose` (dash).
# Prefer v2. bail if neither is available.
if docker compose version >/dev/null 2>&1; then
  COMPOSE="docker compose"
elif command -v docker-compose >/dev/null 2>&1; then
  COMPOSE="docker-compose"
  echo "${YELLOW}[install] Using legacy docker-compose v1. Consider upgrading to Compose v2.${RESET}"
else
  die "docker compose (v2) not found and docker-compose (v1) not on PATH"
fi

if ! docker info >/dev/null 2>&1; then
  die "docker daemon is not reachable. Are you in the 'docker' group, or should you re-run with sudo?"
fi

[[ -f image.tar.gz ]] || die "image.tar.gz not found in $(pwd) — is the bundle complete?"
[[ -f docker-compose.yml ]] || die "docker-compose.yml not found — is the bundle complete?"

# ─── 2. Load image ─────────────────────────────────────────────────
log "Loading Docker image from image.tar.gz (this is the only step that touches the docker daemon's image store)"
# `docker load` prints "Loaded image: <tag>" for each tag in the archive.
# We tee to stderr so the operator sees it, and grep the tag out for
# use in the .env pin step below.
LOAD_OUTPUT="$(gunzip -c image.tar.gz | docker load)"
echo "$LOAD_OUTPUT"
LOADED_TAG="$(echo "$LOAD_OUTPUT" | awk -F': ' '/Loaded image/ {print $2; exit}')"
[[ -n "$LOADED_TAG" ]] || die "docker load did not report a loaded image tag"
log "Loaded image: ${GREEN}${LOADED_TAG}${RESET}"

# ─── 3. .env setup ─────────────────────────────────────────────────
if [[ ! -f .env ]]; then
  cp .env.example .env
  echo "${YELLOW}[install] Created .env from .env.example. Edit it now with real values, then re-run this script.${RESET}"
  echo "         Required: DECT_RELAY_BOT_URL, DECT_RELAY_AGENT_TOKEN, DECT_ADMIN_PASSWORD"
  exit 2
fi

# Pin IMAGE_TAG in .env to the tag we just loaded. Idempotent —
# rewrites the line each run so upgrades to a new tarball tag Just
# Work without operator intervention.
if grep -q '^IMAGE_TAG=' .env; then
  # Portable in-place sed (works on both GNU sed and BSD sed on macOS).
  # The `.bak` tempfile is removed at end.
  sed -i.bak "s|^IMAGE_TAG=.*|IMAGE_TAG=${LOADED_TAG}|" .env
  rm -f .env.bak
else
  printf '\n# Pinned automatically by install.sh on %s\nIMAGE_TAG=%s\n' \
    "$(date -u +%FT%TZ)" "$LOADED_TAG" >> .env
fi
log "Pinned IMAGE_TAG=${LOADED_TAG} in .env"

# Validate the operator has actually filled in the required values —
# .env.example ships with placeholders that would blow up at runtime
# with a less friendly error.
MISSING=()
required_var() {
  local key="$1" val
  val="$(grep -E "^${key}=" .env | tail -1 | cut -d= -f2-)"
  # Strip surrounding quotes and whitespace so both bare and quoted
  # values validate the same.
  val="${val#\"}"; val="${val%\"}"
  val="${val#\'}"; val="${val%\'}"
  val="${val## }"; val="${val%% }"
  if [[ -z "$val" ]] || [[ "$val" == "replace-with-shared-secret" ]] \
      || [[ "$val" == "replace-with-dect-serviceability-password" ]] \
      || [[ "$val" == "wss://your-bot-host.example.com/dect-relay/ws" ]]; then
    MISSING+=("$key")
  fi
}
required_var DECT_RELAY_BOT_URL
required_var DECT_RELAY_AGENT_TOKEN
required_var DECT_ADMIN_PASSWORD

if [[ ${#MISSING[@]} -gt 0 ]]; then
  echo "${RED}[install] .env is missing required values or still has placeholder text:${RESET}"
  for k in "${MISSING[@]}"; do echo "   - $k"; done
  echo "         Edit .env and re-run this script."
  exit 2
fi

# ─── 4. Compose up ─────────────────────────────────────────────────
log "Starting container via ${COMPOSE} up -d"
$COMPOSE up -d

log "Container started. Recent logs:"
sleep 2
$COMPOSE logs --tail=40 dect-relay-agent || true

echo
log "${GREEN}Done.${RESET} Follow live logs with:  ${DIM}${COMPOSE} logs -f dect-relay-agent${RESET}"
log "Stop the agent with:                       ${DIM}${COMPOSE} down${RESET}"