#!/usr/bin/env bash
# Recreate the filestash container running as a chosen uid/gid so that every
# file it writes into the share is owned by a host account (e.g. oier).
#
# Reads FILES_UID / FILES_GID from .env, chowns the filestash_state volume and
# the FILES_DATA_DIR share to that uid, then force-recreates the container.
# Run it FROM THE REPO ROOT on the target host (needs sudo + docker).
#
# Idempotent and cautious: halts on any ambiguity rather than guessing.
# Background + rationale: plan/20-files.md ("Share dir must be owned by uid …").
set -euo pipefail

die() { echo "!! $*" >&2; exit 1; }
info() { echo ">> $*"; }

# --- preconditions -----------------------------------------------------------
[ -f docker-compose.yml ] || die "run this from the repo root (no docker-compose.yml here)"
[ -f .env ]               || die ".env not found — this is a host-local file; run on the target host"

# The compose file must carry the env-driven `user:` directive. If it doesn't,
# this checkout predates the change — pull before running so the recreate below
# actually applies the uid.
grep -q 'user: "${FILES_UID' docker-compose.yml \
  || die "docker-compose.yml has no FILES_UID user directive — 'git pull' first"

# --- resolve target uid/gid from .env ---------------------------------------
FILES_UID="$(grep -E '^FILES_UID=' .env | tail -1 | cut -d= -f2- | tr -d '\047"' )"
FILES_GID="$(grep -E '^FILES_GID=' .env | tail -1 | cut -d= -f2- | tr -d '\047"' )"
[ -n "${FILES_UID:-}" ] || die "FILES_UID unset in .env — add e.g. 'FILES_UID=1002' (oier)"
[ -n "${FILES_GID:-}" ] || die "FILES_GID unset in .env — add e.g. 'FILES_GID=1002' (oier)"
case "$FILES_UID$FILES_GID" in *[!0-9]*) die "FILES_UID/FILES_GID must be numeric (got $FILES_UID:$FILES_GID)";; esac
info "target run user = ${FILES_UID}:${FILES_GID}"

# --- resolve the share dir + the state volume host path ----------------------
FILES_DATA_DIR="$(grep -E '^FILES_DATA_DIR=' .env | tail -1 | cut -d= -f2- | tr -d '\047"' )"
[ -n "${FILES_DATA_DIR:-}" ] || die "FILES_DATA_DIR unset in .env"
[ -d "$FILES_DATA_DIR" ]     || die "share dir does not exist: $FILES_DATA_DIR"

PROJECT="$(basename "$PWD")"                       # compose project name = dir name
VOL="${PROJECT}_filestash_state"
docker volume inspect "$VOL" >/dev/null 2>&1 || die "docker volume '$VOL' not found"
STATE_DIR="$(docker volume inspect "$VOL" --format '{{ .Mountpoint }}')"
[ -n "$STATE_DIR" ] && [ -d "$STATE_DIR" ] || die "could not resolve state volume mountpoint"

info "share dir   = $FILES_DATA_DIR"
info "state dir   = $STATE_DIR (volume $VOL)"

# --- confirm (destructive-ish: chown -R) -------------------------------------
echo
echo "About to:"
echo "  sudo chown -R ${FILES_UID}:${FILES_GID}  $STATE_DIR"
echo "  sudo chown -R ${FILES_UID}:${FILES_GID}  $FILES_DATA_DIR"
echo "  docker compose up -d --force-recreate filestash   (brief downtime)"
read -r -p "Proceed? [y/N] " ans
[ "$ans" = "y" ] || [ "$ans" = "Y" ] || die "aborted by user"

# --- apply -------------------------------------------------------------------
info "stopping filestash"
docker compose stop filestash

info "chowning state volume -> ${FILES_UID}:${FILES_GID}"
sudo chown -R "${FILES_UID}:${FILES_GID}" "$STATE_DIR"

info "chowning share -> ${FILES_UID}:${FILES_GID}"
sudo chown -R "${FILES_UID}:${FILES_GID}" "$FILES_DATA_DIR"

info "recreating filestash as ${FILES_UID}:${FILES_GID}"
docker compose up -d --force-recreate filestash

# --- verify ------------------------------------------------------------------
sleep 3
running="$(docker inspect -f '{{.State.Running}}' filestash 2>/dev/null || echo false)"
[ "$running" = "true" ] || { docker compose logs --tail=40 filestash; die "filestash is not running — see logs above"; }

info "write test as uid ${FILES_UID}"
if docker exec -u "$FILES_UID" filestash sh -c 'touch /data/files/.wtest && rm /data/files/.wtest'; then
  info "OK — filestash writes the share as ${FILES_UID}:${FILES_GID}; new files owned by that user"
else
  docker compose logs --tail=40 filestash
  die "write test FAILED — check share perms + logs above"
fi