#!/usr/bin/env bash
# evOo-local — idempotent deploy helper for the Evo host checkout.
# Pull (or pin) a revision, migrate, restart services, health-check, rollback on failure.
set -euo pipefail

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

# --- defaults (override via env; see ops/evo-deploy/README.md) ---
EVO_DEPLOY_DIR="${EVO_DEPLOY_DIR:-${HOME}/Projects/evOo-local}"
EVO_DEPLOY_REF="${EVO_DEPLOY_REF:-main}"
EVO_GIT_REMOTE="${EVO_GIT_REMOTE:-origin}"
EVO_RESTART_MODE="${EVO_RESTART_MODE:-auto}" # auto | systemd | tmux | compose | script | none
EVO_SYSTEMD_UNIT="${EVO_SYSTEMD_UNIT:-}"
EVO_SYSTEMD_SCOPE="${EVO_SYSTEMD_SCOPE:-user}" # user | system
EVO_TMUX_SESSION="${EVO_TMUX_SESSION:-evoo}"
EVO_TMUX_COMMAND="${EVO_TMUX_COMMAND:-pnpm dev}"
EVO_COMPOSE_FILE="${EVO_COMPOSE_FILE:-infra/compose/docker-compose.yml}"
EVO_COMPOSE_ENV_FILE="${EVO_COMPOSE_ENV_FILE:-.env}"
EVO_COMPOSE_SERVICES="${EVO_COMPOSE_SERVICES:-api web worker}"
EVO_RESTART_SCRIPT="${EVO_RESTART_SCRIPT:-}"
EVO_API_HEALTH_URL="${EVO_API_HEALTH_URL:-http://127.0.0.1:3100/health}"
EVO_WEB_HEALTH_URL="${EVO_WEB_HEALTH_URL:-http://127.0.0.1:5173/}"
EVO_HEALTH_TIMEOUT_SEC="${EVO_HEALTH_TIMEOUT_SEC:-120}"
EVO_MIGRATE="${EVO_MIGRATE:-true}"
EVO_INSTALL="${EVO_INSTALL:-true}"
EVO_DRY_RUN="${EVO_DRY_RUN:-false}"
EVO_STATE_FILE="${EVO_STATE_FILE:-${EVO_DEPLOY_DIR}/.evo-deploy/state.json}"

DRY_RUN=false

log() { printf '[evo-deploy] %s\n' "$*" >&2; }
die() { log "ERROR: $*"; exit 1; }

usage() {
  cat <<'EOF'
Usage: deploy.sh [--dry-run] [--ref REF] [--skip-migrate] [--skip-install]

Environment: EVO_DEPLOY_DIR, EVO_DEPLOY_REF, EVO_RESTART_MODE, EVO_SYSTEMD_UNIT,
  EVO_TMUX_SESSION, EVO_API_HEALTH_URL, EVO_WEB_HEALTH_URL, EVO_HEALTH_TIMEOUT_SEC, …
See ops/evo-deploy/README.md.
EOF
}

parse_args() {
  while [[ $# -gt 0 ]]; do
    case "$1" in
      --dry-run)
        DRY_RUN=true
        EVO_DRY_RUN=true
        shift
        ;;
      --ref)
        [[ $# -ge 2 ]] || die "--ref requires a value"
        EVO_DEPLOY_REF="$2"
        shift 2
        ;;
      --skip-migrate)
        EVO_MIGRATE=false
        shift
        ;;
      --skip-install)
        EVO_INSTALL=false
        shift
        ;;
      -h | --help)
        usage
        exit 0
        ;;
      *)
        die "unknown argument: $1"
        ;;
    esac
  done
  if [[ "$EVO_DRY_RUN" == "true" ]]; then
    DRY_RUN=true
  fi
}

run() {
  if [[ "$DRY_RUN" == true ]]; then
    log "[dry-run] $*"
    return 0
  fi
  "$@"
}

run_shell() {
  if [[ "$DRY_RUN" == true ]]; then
    log "[dry-run] $*"
    return 0
  fi
  bash -lc "$*"
}

validate_deploy_dir() {
  [[ -d "$EVO_DEPLOY_DIR" ]] || die "EVO_DEPLOY_DIR does not exist: $EVO_DEPLOY_DIR"
  [[ -d "$EVO_DEPLOY_DIR/.git" ]] || die "EVO_DEPLOY_DIR is not a git checkout: $EVO_DEPLOY_DIR"
}

resolve_restart_mode() {
  if [[ "$EVO_RESTART_MODE" != "auto" ]]; then
    printf '%s\n' "$EVO_RESTART_MODE"
    return
  fi
  if [[ -n "$EVO_SYSTEMD_UNIT" ]]; then
    printf 'systemd\n'
    return
  fi
  if [[ -n "$EVO_RESTART_SCRIPT" && -x "$EVO_RESTART_SCRIPT" ]]; then
    printf 'script\n'
    return
  fi
  if command -v tmux >/dev/null 2>&1 && tmux has-session -t "$EVO_TMUX_SESSION" 2>/dev/null; then
    printf 'tmux\n'
    return
  fi
  if [[ -f "$EVO_DEPLOY_DIR/$EVO_COMPOSE_FILE" ]]; then
    printf 'compose\n'
    return
  fi
  printf 'none\n'
}

systemctl_cmd() {
  if [[ "$EVO_SYSTEMD_SCOPE" == "system" ]]; then
    if [[ "$(id -u)" -eq 0 ]]; then
      systemctl "$@"
    else
      sudo systemctl "$@"
    fi
  else
    systemctl --user "$@"
  fi
}

restart_systemd() {
  [[ -n "$EVO_SYSTEMD_UNIT" ]] || die "EVO_RESTART_MODE=systemd requires EVO_SYSTEMD_UNIT"
  log "restarting systemd unit: $EVO_SYSTEMD_UNIT ($EVO_SYSTEMD_SCOPE scope)"
  run systemctl_cmd restart "$EVO_SYSTEMD_UNIT"
}

restart_tmux() {
  command -v tmux >/dev/null 2>&1 || die "tmux not found; set EVO_RESTART_MODE=systemd or install tmux"
  log "restarting tmux session '$EVO_TMUX_SESSION' in $EVO_DEPLOY_DIR"
  if [[ "$DRY_RUN" != true ]] && tmux has-session -t "$EVO_TMUX_SESSION" 2>/dev/null; then
    tmux kill-session -t "$EVO_TMUX_SESSION"
  fi
  run_shell "cd $(printf '%q' "$EVO_DEPLOY_DIR") && tmux new-session -d -s $(printf '%q' "$EVO_TMUX_SESSION") -c $(printf '%q' "$EVO_DEPLOY_DIR") $(printf '%q' "$EVO_TMUX_COMMAND")"
}

restart_compose() {
  local compose_path="$EVO_DEPLOY_DIR/$EVO_COMPOSE_FILE"
  [[ -f "$compose_path" ]] || die "compose file not found: $compose_path"
  log "restarting compose services ($EVO_COMPOSE_SERVICES)"
  local env_args=()
  [[ -f "$EVO_DEPLOY_DIR/$EVO_COMPOSE_ENV_FILE" ]] && env_args=(--env-file "$EVO_DEPLOY_DIR/$EVO_COMPOSE_ENV_FILE")
  run_shell "cd $(printf '%q' "$EVO_DEPLOY_DIR") && docker compose ${env_args[*]} -f $(printf '%q' "$EVO_COMPOSE_FILE") up -d --wait $EVO_COMPOSE_SERVICES"
}

restart_script() {
  [[ -n "$EVO_RESTART_SCRIPT" ]] || die "EVO_RESTART_MODE=script requires EVO_RESTART_SCRIPT"
  [[ -x "$EVO_RESTART_SCRIPT" ]] || die "EVO_RESTART_SCRIPT is not executable: $EVO_RESTART_SCRIPT"
  log "running restart script: $EVO_RESTART_SCRIPT"
  run env EVO_DEPLOY_DIR="$EVO_DEPLOY_DIR" "$EVO_RESTART_SCRIPT"
}

restart_services() {
  local mode
  mode="$(resolve_restart_mode)"
  case "$mode" in
    systemd) restart_systemd ;;
    tmux) restart_tmux ;;
    compose) restart_compose ;;
    script) restart_script ;;
    none)
      log "EVO_RESTART_MODE=none — skipping service restart (health check only)"
      ;;
    *)
      die "unsupported restart mode: $mode"
      ;;
  esac
}

wait_for_url() {
  local url="$1"
  local label="$2"
  local timeout="$EVO_HEALTH_TIMEOUT_SEC"
  local start now last=""
  start="$(date +%s)"
  log "health-check $label: $url (timeout ${timeout}s)"
  if [[ "$DRY_RUN" == true ]]; then
    log "[dry-run] would wait for $label at $url"
    return 0
  fi
  while true; do
    now="$(date +%s)"
    if (( now - start >= timeout )); then
      log "ERROR: $label health check timed out after ${timeout}s (last: ${last:-unknown})"
      return 1
    fi
    if curl -fsS --max-time 5 "$url" >/dev/null 2>&1; then
      log "$label healthy"
      return 0
    fi
    last="$(curl -sS -o /dev/null -w '%{http_code}' --max-time 5 "$url" 2>/dev/null || echo unreachable)"
    sleep 2
  done
}

health_check() {
  wait_for_url "$EVO_API_HEALTH_URL" "API"
  wait_for_url "$EVO_WEB_HEALTH_URL" "web"
}

write_state() {
  local previous_sha="$1" target_sha="$2" status="$3"
  if [[ "$DRY_RUN" == true ]]; then
    log "[dry-run] would write state to $EVO_STATE_FILE"
    return 0
  fi
  mkdir -p "$(dirname "$EVO_STATE_FILE")"
  cat >"$EVO_STATE_FILE" <<EOF
{
  "previousSha": "$previous_sha",
  "deployedSha": "$target_sha",
  "ref": "$EVO_DEPLOY_REF",
  "status": "$status",
  "at": "$(date -u +%Y-%m-%dT%H:%M:%SZ)"
}
EOF
}

git_fetch_and_checkout() {
  local previous_sha target_sha
  previous_sha="$(git -C "$EVO_DEPLOY_DIR" rev-parse HEAD)"
  log "previous HEAD: $previous_sha"
  log "fetching $EVO_GIT_REMOTE…"
  run git -C "$EVO_DEPLOY_DIR" fetch "$EVO_GIT_REMOTE" --prune
  if git -C "$EVO_DEPLOY_DIR" rev-parse --verify "${EVO_DEPLOY_REF}^{commit}" >/dev/null 2>&1; then
    target_sha="$(git -C "$EVO_DEPLOY_DIR" rev-parse "${EVO_DEPLOY_REF}^{commit}")"
  elif git -C "$EVO_DEPLOY_DIR" rev-parse --verify "${EVO_GIT_REMOTE}/${EVO_DEPLOY_REF}^{commit}" >/dev/null 2>&1; then
    target_sha="$(git -C "$EVO_DEPLOY_DIR" rev-parse "${EVO_GIT_REMOTE}/${EVO_DEPLOY_REF}^{commit}")"
  else
    die "cannot resolve ref: $EVO_DEPLOY_REF"
  fi
  log "checking out $target_sha ($EVO_DEPLOY_REF)"
  run git -C "$EVO_DEPLOY_DIR" reset --hard "$target_sha"
  printf '%s %s\n' "$previous_sha" "$target_sha"
}

run_migrate() {
  [[ "$EVO_MIGRATE" == "true" ]] || { log "skipping migrate (EVO_MIGRATE=false)"; return 0; }
  if [[ ! -f "$EVO_DEPLOY_DIR/package.json" ]]; then
    die "package.json missing in $EVO_DEPLOY_DIR"
  fi
  if ! grep -q '"db:migrate"' "$EVO_DEPLOY_DIR/package.json"; then
    log "no db:migrate script in package.json — skipping migrations"
    return 0
  fi
  log "running pnpm db:generate && pnpm db:migrate"
  run_shell "cd $(printf '%q' "$EVO_DEPLOY_DIR") && pnpm db:generate && pnpm db:migrate"
}

run_install() {
  [[ "$EVO_INSTALL" == "true" ]] || { log "skipping install (EVO_INSTALL=false)"; return 0; }
  log "running pnpm install --frozen-lockfile"
  run_shell "cd $(printf '%q' "$EVO_DEPLOY_DIR") && pnpm install --frozen-lockfile"
}

rollback() {
  local previous_sha="$1"
  log "ROLLBACK: resetting to $previous_sha and restarting services"
  run git -C "$EVO_DEPLOY_DIR" reset --hard "$previous_sha"
  restart_services
  write_state "$previous_sha" "$previous_sha" "rolled-back"
  die "deploy failed; rolled back to $previous_sha"
}

main() {
  parse_args "$@"
  validate_deploy_dir

  local resolved_mode
  resolved_mode="$(resolve_restart_mode)"
  log "deploy dir: $EVO_DEPLOY_DIR"
  log "target ref: $EVO_DEPLOY_REF"
  log "restart mode: $resolved_mode"
  [[ "$DRY_RUN" == true ]] && log "dry-run enabled — no mutating commands"

  local previous_sha target_sha
  read -r previous_sha target_sha < <(git_fetch_and_checkout)

  if [[ "$previous_sha" == "$target_sha" && "$DRY_RUN" != true ]]; then
    log "already at $target_sha — continuing with migrate/restart/health"
  fi

  run_install
  run_migrate
  restart_services

  if ! health_check; then
    rollback "$previous_sha"
    exit 1
  fi

  write_state "$previous_sha" "$target_sha" "success"
  log "deploy succeeded: $previous_sha -> $target_sha"
}

main "$@"