package store

import (
	"fmt"
	"path/filepath"
	"time"

	"github.com/google/uuid"
	"printer.backend/internal/model"
	"printer.backend/internal/paths"
)

// ConfigurationStore persists configurations as JSON files.
type ConfigurationStore struct {
	dir string
}

// NewConfigurationStore creates a store under dir (default data/configurations).
func NewConfigurationStore(dir string) *ConfigurationStore {
	if dir == "" {
		dir = paths.ConfigurationsDir
	}
	return &ConfigurationStore{dir: dir}
}

// List returns all configurations sorted by creation time (newest first).
func (s *ConfigurationStore) List() ([]model.Configuration, error) {
	return listFromDir(s.dir,
		func(name string) bool { return filepath.Ext(name) == ".json" },
		"configurations dir",
		func(c model.Configuration) time.Time { return c.CreatedAt },
	)
}

// Get returns a configuration by ID.
func (s *ConfigurationStore) Get(id string) (model.Configuration, error) {
	list, err := s.List()
	if err != nil {
		return model.Configuration{}, err
	}
	return findByID(list, id, func(c model.Configuration) string { return c.ID })
}

// Save writes a new configuration and assigns an ID when empty.
func (s *ConfigurationStore) Save(c model.Configuration) (model.Configuration, error) {
	if err := ensureDir(s.dir); err != nil {
		return model.Configuration{}, err
	}
	if c.ID == "" {
		c.ID = uuid.NewString()
	}
	c.CreatedAt = stampNew(&c.CreatedAt)

	path := filepath.Join(s.dir, c.ID+".json")
	if err := writeJSON(path, c); err != nil {
		return model.Configuration{}, fmt.Errorf("write configuration: %w", err)
	}
	return c, nil
}

// Delete removes a configuration by ID.
func (s *ConfigurationStore) Delete(id string) error {
	path := filepath.Join(s.dir, id+".json")
	return removeFile(path, fmt.Sprintf("configuration not found: %s", id))
}