package sitesvc

import (
	"context"
	"errors"
	"fmt"
	"regexp"
	"strings"

	"github.com/panelhosting/panel/internal/models"
	"github.com/panelhosting/panel/internal/repository"
)

var (
	ErrInvalidSiteName   = errors.New("site name must be 3-64 chars: lowercase letters, digits, hyphen")
	ErrInvalidDomain     = errors.New("invalid domain")
	ErrInvalidPHPVersion = errors.New("unsupported php version")
)

var (
	siteNameRegex = regexp.MustCompile(`^[a-z0-9][a-z0-9-]{1,62}[a-z0-9]$`)
	domainRegex   = regexp.MustCompile(`^(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z]{2,}$`)
)

type Service struct {
	sites    *repository.SiteRepository
	servers  *repository.ServerRepository
	phpVers  *repository.PHPVersionRepository
}

func NewService(sites *repository.SiteRepository, servers *repository.ServerRepository, php *repository.PHPVersionRepository) *Service {
	return &Service{sites: sites, servers: servers, phpVers: php}
}

type CreateInput struct {
	Name       string
	Domain     string
	PHPVersion string
	ServerID   int64
	OwnerID    int64
	IsAdmin    bool
}

func (s *Service) List(ctx context.Context, user *models.User, isAdmin bool) ([]repository.SiteWithDomain, error) {
	return s.sites.ListForUser(ctx, user.ID, isAdmin)
}

func (s *Service) ListPHPVersions(ctx context.Context) ([]string, error) {
	return s.phpVers.ListActive(ctx)
}

func (s *Service) Create(ctx context.Context, in CreateInput) (*repository.SiteWithDomain, error) {
	name := strings.ToLower(strings.TrimSpace(in.Name))
	domain := strings.ToLower(strings.TrimSpace(in.Domain))
	phpVersion := strings.TrimSpace(in.PHPVersion)

	if !siteNameRegex.MatchString(name) {
		return nil, ErrInvalidSiteName
	}
	if !domainRegex.MatchString(domain) {
		return nil, ErrInvalidDomain
	}
	if phpVersion == "" {
		return nil, ErrInvalidPHPVersion
	}

	active, err := s.phpVers.IsActive(ctx, phpVersion)
	if err != nil {
		return nil, err
	}
	if !active {
		return nil, ErrInvalidPHPVersion
	}

	serverID := in.ServerID
	if serverID == 0 {
		srv, err := s.servers.GetFirst(ctx)
		if err != nil {
			return nil, fmt.Errorf("no server available: %w", err)
		}
		serverID = srv.ID
	} else {
		if _, err := s.servers.GetByID(ctx, serverID); err != nil {
			return nil, err
		}
	}

	documentRoot := fmt.Sprintf("/var/www/%s/public", name)
	return s.sites.Create(ctx, serverID, in.OwnerID, name, documentRoot, phpVersion, domain)
}