#!/usr/bin/env bash
#
# Deploy Solid Scribe. Run this ON the server, from inside the repo.
#
#   cd /path/to/SolidScribe && ./deploy.sh
#
# Replaces buildAndUpdateProd.sh, which built the old Vue 2 client and rsynced a
# tarball to /home/mab/pi -- a directory that no longer exists.
#
# Assumes:
#   - this repo is a git clone with a tracking branch
#   - node + pnpm are on PATH for the user running this (on NixOS that means
#     environment.systemPackages or the user's profile -- NOT only inside a
#     nix-shell, or this will fail at the install step)
#   - pm2 is already managing NoteServer (pm2 resurrect on boot)
#   - nginx serves $WEBROOT/current with an SPA fallback to index.html
#
# nginx is NOT touched here. On NixOS it is declarative -- see configs/.
#
# --- the web root --------------------------------------------------------
#
# The built client is published to /var/www/ss, NOT served out of the repo.
# nginx runs as its own user, so serving from a clone under /home/mab meant
# loosening the home directory's permissions for every parent dir. /var/www is
# the conventional place for this and sidesteps the whole problem.
#
# Layout, which is the standard symlink-swap pattern:
#
#   /var/www/ss/
#     releases/2026-10-28_1147/   <- one directory per deploy
#     releases/2026-10-28_0930/
#     current -> releases/2026-10-28_1147
#
# nginx points at the stable path $WEBROOT/current. Publishing is a rename of
# that symlink, which is a single atomic syscall: no request ever sees a
# half-copied directory, and no window exists where the root is missing.
# Rolling back is the same rename pointing at the previous release.
#
# Only the *client* moves. The API server still runs from the repo under pm2,
# and user uploads are still served by Express from $REPO/staticFiles at
# /api/static -- deliberately, so deploys never touch user data.
#
# ONE-TIME SETUP on a new server (needs root):
#
#   sudo mkdir -p /var/www/ss/releases
#   sudo chown -R "$USER" /var/www/ss
#   sudo chmod 755 /var/www /var/www/ss
#
# Override the location for a staging box with:  WEBROOT=/var/www/ss-staging ./deploy.sh
#

set -euo pipefail

REPO="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$REPO"

WEBROOT="${WEBROOT:-/var/www/ss}"
RELEASE="$WEBROOT/releases/$(date +%Y-%m-%d_%H%M%S)"
# Number of old releases to keep around for rollback.
KEEP_RELEASES=5

step(){ printf '\n\033[32m::--:: %s\033[0m\n' "$1"; }

# --- sanity checks before changing anything ------------------------------

for tool in git pnpm pm2 rsync; do
	command -v "$tool" >/dev/null || { echo "$tool is not on PATH" >&2; exit 1; }
done

# Fail here rather than after a three-minute build. A missing web root is
# almost always a server that never had the one-time setup above run on it.
if [ ! -d "$WEBROOT/releases" ]; then
	echo "$WEBROOT/releases does not exist -- run the one-time setup at the top of this script." >&2
	exit 1
fi

if [ ! -w "$WEBROOT/releases" ]; then
	echo "$WEBROOT/releases is not writable by $(whoami) -- check the chown in the one-time setup." >&2
	exit 1
fi

if [ -n "$(git status --porcelain --untracked-files=no)" ]; then
	echo "Working tree has local modifications. Commit or stash them first:" >&2
	git status --short >&2
	exit 1
fi

# --- pull ----------------------------------------------------------------

step "Pulling $(git rev-parse --abbrev-ref HEAD)..."
# --ff-only: refuse to create a merge commit on the server. If this fails the
# server has diverged and wants a human.
git pull --ff-only

# --- dependencies --------------------------------------------------------

step "Installing server dependencies..."
pnpm install --frozen-lockfile

step "Installing client dependencies..."
pnpm install --frozen-lockfile --dir client

# --- build ---------------------------------------------------------------

# dist is gitignored, so the server builds it. The build stays inside the repo
# and is only copied to $WEBROOT once it has been checked, so a failed build
# cannot touch what is currently being served.
step "Building client..."
rm -rf client/dist
pnpm --dir client exec vite build

# manifest.json is checked in under client/public and copied verbatim by Vite;
# if it is missing, the PWA installs without icons, scope or a share target.
for required in index.html sw.js manifest.json; do
	if [ ! -f "client/dist/$required" ]; then
		echo "Build output looks wrong (missing $required) -- $WEBROOT left untouched." >&2
		exit 1
	fi
done

# --- publish -------------------------------------------------------------

step "Publishing to $RELEASE..."
mkdir -p "$RELEASE"
# Trailing slash on the source: copy the *contents* of dist into the release
# dir. --delete is harmless on a fresh dir but keeps a re-run of the same
# timestamp honest.
rsync -a --delete client/dist/ "$RELEASE/"

# nginx reads these as its own user, so they must be world-readable.
chmod -R a+rX "$RELEASE"

step "Pointing $WEBROOT/current at the new release..."
# Two steps because `ln -sfn` over an existing symlink unlinks before relinking,
# which leaves a brief window with no web root at all. Creating a scratch
# symlink and renaming it over the old one is a single atomic rename(2).
ln -sfn "$RELEASE" "$WEBROOT/current.new"
mv -T "$WEBROOT/current.new" "$WEBROOT/current"

# --- prune ---------------------------------------------------------------

# Keep the most recent $KEEP_RELEASES for rollback, drop the rest. Never remove
# whatever `current` actually resolves to, however old it is.
live="$(readlink -f "$WEBROOT/current")"
ls -1d "$WEBROOT"/releases/*/ 2>/dev/null \
	| sort -r \
	| tail -n +$((KEEP_RELEASES + 1)) \
	| while read -r stale; do
		[ "$(readlink -f "$stale")" = "$live" ] && continue
		echo "  pruning $(basename "$stale")"
		rm -rf "$stale"
	done

# --- restart -------------------------------------------------------------

step "Reloading the API server..."
# reload, not restart: graceful in cluster mode. --update-env so changes to
# ecosystem.config.js are picked up.
pm2 reload "$REPO/server/ecosystem.config.js" --env production --update-env

# Persist the process list so `pm2 resurrect` on boot gets the current state.
pm2 save

step "Done."
echo "  serving $(readlink -f "$WEBROOT/current")"
echo
echo "  To roll back, repoint the symlink at the previous release:"
echo "    ls $WEBROOT/releases"
echo "    ln -sfn $WEBROOT/releases/<older> $WEBROOT/current.new && mv -T $WEBROOT/current.new $WEBROOT/current"
echo
pm2 list