#!/usr/bin/env bash
# dxkit/runtime/runtime.sh
#
# Runtime abstraction layer.
# Commands and modules call runtime::* — this file dispatches to
# the active driver based on RUNTIME_DRIVER (default: docker).

# ============================================
# Driver loader
# ============================================

RUNTIME_DRIVER="${RUNTIME_DRIVER:-docker}"

function runtime::driver()  { echo "${RUNTIME_DRIVER}"; }
function runtime::service() { echo "${APP_SERVICE:-app}"; }

function runtime::_load_driver() {
  local driver_file
  driver_file="$(ctx::dxkit)/runtime/${RUNTIME_DRIVER}.runtime.sh"

  if [[ ! -f "$driver_file" ]]; then
    log::error "Unknown runtime driver: '${RUNTIME_DRIVER}'"
    log::error "Expected: ${driver_file}"
    return 1
  fi

  source "$driver_file"
}

runtime::_load_driver

# ============================================
# Interface
# ============================================

function runtime::up()        { "runtime::$(runtime::driver)::up"        "$@"; }
function runtime::down()      { "runtime::$(runtime::driver)::down"      "$@"; }
function runtime::logs()      { "runtime::$(runtime::driver)::logs"      "$@"; }
function runtime::list()      { "runtime::$(runtime::driver)::list"      "$@"; }
function runtime::status()    { "runtime::$(runtime::driver)::status"    "$@"; }
function runtime::build()     { "runtime::$(runtime::driver)::build"     "$@"; }
function runtime::ensure()    { "runtime::$(runtime::driver)::ensure"    "$@"; }
function runtime::is_inside() { "runtime::$(runtime::driver)::is_inside" "$@"; }

# Exec and shell are special — they handle "running inside the runtime"
# vs "running on host" transparently
function runtime::exec() {
  local args=("$@")
  [[ "${#args[@]}" -eq 0 ]] && return 1

  if runtime::is_inside; then
    "${args[@]}"
  else
    runtime::ensure
    "runtime::$(runtime::driver)::exec" "${args[@]}"
  fi
}

function runtime::shell() {
  if runtime::is_inside; then
    runtime::_local_shell
  else
    runtime::ensure
    "runtime::$(runtime::driver)::shell"
  fi
}

# Conditionally run a function based on a flag value.
# Driver-agnostic — useful in build pipelines.
function runtime::run_if() {
  local flag="$1"
  shift

  if [[ "${!flag:-}" == true ]]; then
    "$@" || return 1
  fi
}

# ============================================
# Internal helpers
# ============================================

function runtime::_local_shell() {
  if command -v bash >/dev/null 2>&1; then
    bash
  else
    sh
  fi
}