package library

import (
	"context"
	"errors"
	"log/slog"

	"pipu/api/internal/auth"
	"pipu/api/internal/platform/apperr"
)

// Коды ошибок библиотеки.
const (
	CodeSourceNotFound   = "library.source_not_found"
	CodeScanRunning      = "library.scan_running"
	CodeSourceOffline    = "library.source_offline"
	CodePatternInvalid   = "validation.pattern_invalid"
	CodeNFSInvalid       = "validation.nfs_invalid"
	CodeLocalPathInvalid = "validation.local_path_invalid"
	CodeNameInvalid      = "validation.name_invalid"
	CodeIntervalInvalid  = "validation.scan_interval_invalid"
	CodeNotFound         = "catalog.not_found"
	CodeTemplateInvalid  = "validation.template_invalid"
	CodeTemplateNone     = "library.template_unavailable"
)

// Config — пути к хранилищам в файловой системе api.
type Config struct {
	LibraryRoot string // точки монтирования NFS: <root>/<source_id>
	HostRoot    string // LIBRARY_HOST внутри контейнера, для local-источников
}

// Service preserves the API while each use case owns only its dependencies.
type Service struct {
	*SourceService
	*TemplateService
	*ScanService
	*Scheduler
}

func NewService(store *Store, scanner *Scanner, board *ProgressBoard, agent Agent, prober Prober, cfg Config, log *slog.Logger) *Service {
	sources := &SourceService{store: store, board: board, agent: agent, cfg: cfg, log: log}
	scans := &ScanService{store: store, scanner: scanner, board: board, root: sources.Root}
	return &Service{
		SourceService:   sources,
		TemplateService: &TemplateService{store: store, prober: prober, root: sources.Root},
		ScanService:     scans,
		Scheduler:       &Scheduler{store: store, sources: sources, scans: scans, log: log},
	}
}

func forbidden() error { return apperr.Forbidden(auth.CodeForbidden, "not allowed") }

func requirePerm(ctx context.Context, perm auth.Permission) error {
	p, ok := auth.PrincipalFrom(ctx)
	if !ok {
		return apperr.Unauthorized(auth.CodeUnauthorized, "not authenticated")
	}
	if !auth.Can(p.Role, perm) {
		return forbidden()
	}
	return nil
}

func notFound(err error) error {
	if errors.Is(err, ErrNotFound) {
		return apperr.NotFound(CodeSourceNotFound, "source not found")
	}
	return err
}