package storage

import (
	"context"
	"errors"
	"time"

	"forge.cadoles.com/arcad/edge/pkg/storage/filter"
	"github.com/oklog/ulid/v2"
)

var (
	ErrDocumentNotFound         = errors.New("document not found")
	ErrDocumentRevisionConflict = errors.New("document revision conflict")
)

type DocumentID string

const (
	DocumentAttrID        = "_id"
	DocumentAttrRevision  = "_revision"
	DocumentAttrCreatedAt = "_createdAt"
	DocumentAttrUpdatedAt = "_updatedAt"
)

func NewDocumentID() DocumentID {
	return DocumentID(ulid.Make().String())
}

type Document map[string]interface{}

func (d Document) ID() (DocumentID, bool) {
	rawID, exists := d[DocumentAttrID]
	if !exists {
		return "", false
	}

	strID, ok := rawID.(string)
	if ok {
		return DocumentID(strID), true
	}

	docID, ok := rawID.(DocumentID)
	if ok {
		return docID, true
	}

	return "", false
}

func (d Document) Revision() (int, bool) {
	rawRevision, exists := d[DocumentAttrRevision]
	if !exists {
		return 0, false
	}

	revision, ok := rawRevision.(int)
	if ok {
		return revision, true
	}

	return 0, false
}

func (d Document) CreatedAt() (time.Time, bool) {
	return d.timeAttr(DocumentAttrCreatedAt)
}

func (d Document) UpdatedAt() (time.Time, bool) {
	return d.timeAttr(DocumentAttrUpdatedAt)
}

func (d Document) timeAttr(attr string) (time.Time, bool) {
	rawTime, exists := d[attr]
	if !exists {
		return time.Time{}, false
	}

	t, ok := rawTime.(time.Time)
	if !ok {
		return time.Time{}, false
	}

	return t, true
}

type DocumentStore interface {
	Get(ctx context.Context, collection string, id DocumentID) (Document, error)
	Query(ctx context.Context, collection string, filter *filter.Filter, funcs ...QueryOptionFunc) ([]Document, error)
	Upsert(ctx context.Context, collection string, document Document) (Document, error)
	Delete(ctx context.Context, collection string, id DocumentID) error
}