package ejs

import (
	"encoding/json"
	"fmt"
	"os"
	"strings"
)

type Store struct {
	path string
}

type Search interface {
	match([]byte) bool
}

func NewStore(path string) (Store, error) {
	s := Store{}
	s.path = path

	err := s.createFolderIfNeeded(path)
	if err != nil {
		return Store{}, err
	}

	return s, nil
}

func (s Store) Save(dataset, id string, data any) error {
	err := s.createFolderIfNeeded(fmt.Sprintf("%v/%v", s.path, dataset))
	if err != nil {
		return err
	}

	jsonData, err := json.Marshal(data)
	if err != nil {
		return err
	}

	os.WriteFile(fmt.Sprintf("%v/%v/%v.json", s.path, dataset, id), jsonData, 0600)
	return nil
}

func (s Store) List(dataset string) ([]string, error) {
	entries, err := os.ReadDir(fmt.Sprintf("%v/%v/", s.path, dataset))
	if err != nil {
		return []string{}, err
	}

	var entrylist []string
	for _, e := range entries {
		name := e.Name()
		name = strings.TrimRight(name, ".json")
		entrylist = append(entrylist, name)
	}

	return entrylist, nil
}

func (s Store) Get(dataset, id string, data any) error {
	content, err := os.ReadFile(fmt.Sprintf("%v/%v/%v.json", s.path, dataset, id))
	if err != nil {
		return err
	}

	err = json.Unmarshal(content, data)
	if err != nil {
		return err
	}

	return nil
}

func (s Store) Scan(dataset string, cbFunc func(id string)) error {
	ids, err := s.List(dataset)
	if err != nil {
		return err
	}
	for _, id := range ids {
		cbFunc(id)
	}
	return nil
}

func (s Store) Search(dataset string, searchFilter ...Search) ([]string, error) {
	ids, err := s.List(dataset)
	if err != nil {
		return []string{}, err
	}

	found := []string{}

	for _, id := range ids {
		content, err := os.ReadFile(fmt.Sprintf("%v/%v/%v.json", s.path, dataset, id))
		if err != nil {
			return []string{}, err
		}

		match := true
		for _, search := range searchFilter {
			if !search.match(content) {
				match = false
			}
		}

		if match {
			found = append(found, id)
		}
	}

	return found, nil
}

func (s Store) createFolderIfNeeded(path string) error {
	_, err := os.Stat(path)
	if err == nil {
		return nil
	}
	if !os.IsNotExist(err) {
		return err
	}

	err = os.Mkdir(path, 0700)
	if err != nil {
		return err
	}

	return nil
}