package storage

import (
	"donniemarko/internal/note"
	"fmt"
	"strings"
)

type Storage interface {
	GetAll() []*note.Note
	Get(id string) (*note.Note, error)
	Create(n *note.Note) error
	Delete(id string)
	Update(id string, n *note.Note)
	Search(query string) []*note.Note
	Count() int
	AddTag(noteID, tag string) error
	RemoveTag(noteID, tag string) error
	GetTags(noteID string) []string
}

type NoteStorage struct {
	Index map[string]*note.Note
}

func NewNoteStorage() *NoteStorage {
	return &NoteStorage{Index: make(map[string]*note.Note)}
}

// GetAll returns all notes stored in the index
func (ns *NoteStorage) GetAll() []*note.Note {
	var notes []*note.Note

	for _, value := range ns.Index {
		notes = append(notes, value)
	}
	return notes
}

func (ns *NoteStorage) Get(id string) (*note.Note, error) {
	n, ok := ns.Index[id]
	if ok {
		return n, nil
	}
	return nil, fmt.Errorf("No note with id '%s'", id)
}

func (ns *NoteStorage) Create(n *note.Note) error {
	ns.Index[n.ID] = n
	return nil
}

func (ns *NoteStorage) Count() int {
	return len(ns.Index)
}

func (ns *NoteStorage) Delete(id string) {
	delete(ns.Index, id)
}

func (ns *NoteStorage) Update(id string, n *note.Note) {
	ns.Index[id] = n
}

func (ns *NoteStorage) Search(query string) []*note.Note {
	results := []*note.Note{}
	for _, note := range ns.Index {
		lowContent := strings.ToLower(string(note.Content))
		lowQuery := strings.ToLower(query)
		if strings.Contains(lowContent, lowQuery) {
			results = append(results, note)
		}
	}
	return results
}

func (ns *NoteStorage) AddTag(noteID, tag string) error {
	n, ok := ns.Index[noteID]
	if !ok {
		return fmt.Errorf("No note with id '%s'", noteID)
	}

	for _, existing := range n.Tags {
		if existing == tag {
			return nil
		}
	}

	n.Tags = append(n.Tags, tag)
	return nil
}

func (ns *NoteStorage) RemoveTag(noteID, tag string) error {
	n, ok := ns.Index[noteID]
	if !ok {
		return fmt.Errorf("No note with id '%s'", noteID)
	}

	updated := n.Tags[:0]
	for _, existing := range n.Tags {
		if existing != tag {
			updated = append(updated, existing)
		}
	}
	n.Tags = updated
	return nil
}

func (ns *NoteStorage) GetTags(noteID string) []string {
	n, ok := ns.Index[noteID]
	if !ok {
		return []string{}
	}

	tags := make([]string, len(n.Tags))
	copy(tags, n.Tags)
	return tags
}