package servers

import (
	"context"
	"errors"
	"fmt"
	"time"

	"github.com/hashicorp/boundary/globals"
	"github.com/hashicorp/boundary/internal/db"
	"github.com/hashicorp/boundary/internal/kms"
	"github.com/hashicorp/boundary/internal/types/resource"
)

const (
	defaultLiveness = 15 * time.Second
)

type ServerType string

const (
	ServerTypeController ServerType = "controller"
	ServerTypeWorker     ServerType = "worker"
)

func (s ServerType) String() string {
	return string(s)
}

// Repository is the servers database repository
type Repository struct {
	reader db.Reader
	writer db.Writer
	kms    *kms.Kms
}

// NewRepository creates a new servers Repository. Supports the options: WithLimit
// which sets a default limit on results returned by repo operations.
func NewRepository(r db.Reader, w db.Writer, kms *kms.Kms) (*Repository, error) {
	if r == nil {
		return nil, errors.New("error creating server repository with nil reader")
	}
	if w == nil {
		return nil, errors.New("error creating server repository with nil writer")
	}
	if kms == nil {
		return nil, errors.New("error creating server repository with nil kms")
	}
	return &Repository{
		reader: r,
		writer: w,
		kms:    kms,
	}, nil
}

// list will return a listing of resources and honor the WithLimit option or the
// repo defaultLimit
func (r *Repository) ListServers(ctx context.Context, serverType ServerType, opt ...Option) ([]*Server, error) {
	opts := getOpts(opt...)
	liveness := opts.withLiveness
	if liveness == 0 {
		liveness = defaultLiveness
	}
	updateTime := time.Now().Add(-1 * liveness)
	var servers []*Server
	if err := r.reader.SearchWhere(
		ctx,
		&servers,
		"type = $1 and update_time > $2",
		[]interface{}{serverType, updateTime.Format(time.RFC3339)},
		db.WithLimit(-1),
	); err != nil {
		return nil, fmt.Errorf("error listing servers: %w", err)
	}
	return servers, nil
}

// UpsertServer adds or updates a server in the DB
func (r *Repository) UpsertServer(ctx context.Context, server *Server, opt ...Option) ([]*Server, int, error) {
	if server == nil {
		return nil, db.NoRowsAffected, errors.New("cannot update server that is nil")
	}
	// Ensure, for now at least, the private ID is always equivalent to the name
	server.PrivateId = server.Name
	// Build query
	q := `
	insert into server
		(private_id, type, name, description, address, update_time)
	values
		($1, $2, $3, $4, $5, $6)
	on conflict on constraint server_pkey
	do update set
		name = $3,
		description = $4,
		address = $5,
		update_time = $6;
	`

	rowsAffected, err := r.writer.Exec(ctx, q,
		[]interface{}{server.PrivateId,
			server.Type,
			server.Name,
			server.Description,
			server.Address,
			time.Now().Format(time.RFC3339)})
	if err != nil {
		return nil, db.NoRowsAffected, fmt.Errorf("error performing status upsert: %w", err)
	}
	// If updating a controller, done
	if server.Type == resource.Controller.String() {
		return nil, int(rowsAffected), nil
	}
	// Fetch current controllers to feed to the workers
	controllers, err := r.ListServers(ctx, ServerTypeController)
	return controllers, len(controllers), err
}

type RecoveryNonce struct {
	Nonce string
}

// AddRecoveryNonce adds a nonce
func (r *Repository) AddRecoveryNonce(ctx context.Context, nonce string, opt ...Option) error {
	if nonce == "" {
		return errors.New("empty nonce provided")
	}
	rn := &RecoveryNonce{Nonce: nonce}
	if err := r.writer.Create(ctx, rn); err != nil {
		return fmt.Errorf("error performing nonce insertion: %w", err)
	}
	return nil
}

// CleanupNonces removes nonces that no longer need to be stored
func (r *Repository) CleanupNonces(ctx context.Context, opt ...Option) (int, error) {
	// If something was inserted before 3x the actual validity period, clean it out
	endTime := time.Now().Add(-3 * globals.RecoveryTokenValidityPeriod)

	rows, err := r.writer.Delete(ctx, &RecoveryNonce{}, db.WithWhere(deleteWhereSql, endTime))
	if err != nil {
		return db.NoRowsAffected, fmt.Errorf("error performing nonce cleanup: %w", err)
	}
	return rows, nil
}

// ListNonces lists nonces. Used only for tests at the moment.
func (r *Repository) ListNonces(ctx context.Context, opt ...Option) ([]*RecoveryNonce, error) {
	var nonces []*RecoveryNonce
	if err := r.reader.SearchWhere(ctx, &nonces, "", nil, db.WithLimit(-1)); err != nil {
		return nil, fmt.Errorf("error listing nonces: %w", err)
	}
	return nonces, nil
}