package state

import (
	"io/ioutil"
	"os"
	"path/filepath"

	"github.com/boltdb/bolt"
	"github.com/hashicorp/go-hclog"
	"github.com/mitchellh/go-testing-interface"
	"github.com/stretchr/testify/require"
)

// TestState returns an initialized State for testing.
func TestState(t testing.T) *State {
	result, err := New(hclog.L(), testDB(t))
	require.NoError(t, err)
	return result
}

// TestStateReinit reinitializes the state by pretending to restart
// the server with the database associated with this state. This can be
// used to test index init logic.
//
// This safely copies the entire DB so the old state can continue running
// with zero impact.
func TestStateReinit(t testing.T, s *State) *State {
	// Copy the old database to a brand new path
	td, err := ioutil.TempDir("", "test")
	require.NoError(t, err)
	t.Cleanup(func() { os.RemoveAll(td) })
	path := filepath.Join(td, "test.db")

	// Start db copy
	require.NoError(t, s.db.View(func(tx *bolt.Tx) error {
		return tx.CopyFile(path, 0600)
	}))

	// Open the new DB
	db, err := bolt.Open(path, 0600, nil)
	require.NoError(t, err)
	t.Cleanup(func() { db.Close() })

	// Init new state
	result, err := New(hclog.L(), db)
	require.NoError(t, err)
	return result
}

// TestStateRestart closes the given state and restarts it against the
// same DB file. Unlike TestStateReinit, this does not copy the data and
// the old state is no longer usable.
func TestStateRestart(t testing.T, s *State) (*State, error) {
	path := s.db.Path()
	require.NoError(t, s.Close())

	// Open the new DB
	db, err := bolt.Open(path, 0600, nil)
	require.NoError(t, err)
	t.Cleanup(func() { db.Close() })

	// Init new state
	return New(hclog.L(), db)
}

func testDB(t testing.T) *bolt.DB {
	t.Helper()

	// Temporary directory for the database
	td, err := ioutil.TempDir("", "test")
	require.NoError(t, err)
	t.Cleanup(func() { os.RemoveAll(td) })

	// Create the DB
	db, err := bolt.Open(filepath.Join(td, "test.db"), 0600, nil)
	require.NoError(t, err)
	t.Cleanup(func() { db.Close() })

	return db
}