aven 0.1.10

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

script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
repo_root="$(cd "$script_dir/.." && pwd)"
migrations_dir="$repo_root/migrations"
target_ref="${WM_TARGET_BRANCH:-main}"

usage() {
  printf 'usage: %s <lower-snake-name>\n' "$(basename "$0")" >&2
}

error() {
  printf 'error: %s\n' "$*" >&2
}

if [[ $# -ne 1 ]]; then
  usage
  exit 2
fi

name="$1"
if [[ ! "$name" =~ ^[a-z0-9]+(_[a-z0-9]+)*$ ]]; then
  error "migration name must be lower snake case"
  usage
  exit 2
fi

mkdir -p "$migrations_dir"

timestamp="$(date -u +%Y%m%d%H%M%S)"

latest_timestamp=""
record_latest_timestamp() {
  local file_name="$1"
  local candidate
  if [[ "$file_name" =~ ^[0-9]{14}_.*\.sql$ ]]; then
    candidate="${file_name%%_*}"
    if [[ -z "$latest_timestamp" || "$candidate" > "$latest_timestamp" ]]; then
      latest_timestamp="$candidate"
    fi
  fi
}

while IFS= read -r path; do
  record_latest_timestamp "$(basename "$path")"
done < <(find "$migrations_dir" -maxdepth 1 -type f -name '*.sql' -print)

if git -C "$repo_root" rev-parse --verify --quiet "$target_ref^{commit}" >/dev/null; then
  while IFS= read -r path; do
    record_latest_timestamp "$(basename "$path")"
  done < <(git -C "$repo_root" ls-tree -r --name-only "$target_ref" -- migrations '*.sql')
fi

if [[ -n "$latest_timestamp" ]]; then
  attempts=0
  while [[ "$timestamp" < "$latest_timestamp" || "$timestamp" == "$latest_timestamp" ]]; do
    if [[ "$attempts" -ge 5 ]]; then
      error "current UTC timestamp is not after latest migration: $latest_timestamp"
      exit 1
    fi
    sleep 1
    timestamp="$(date -u +%Y%m%d%H%M%S)"
    attempts=$((attempts + 1))
  done
fi

path="$migrations_dir/${timestamp}_${name}.sql"
relative_path="${path#"$repo_root"/}"
if [[ -e "$path" ]]; then
  error "migration already exists: $relative_path"
  exit 1
fi

: >"$path"
printf '%s\n' "$relative_path"