package vex

import (
	"fmt"
	"time"

	"github.com/google/uuid"
	"github.com/jmoiron/sqlx"
	"github.com/lib/pq"
)

type Feed struct {
	Id            uuid.UUID `json:"id"`
	Name          string    `json:"name"`
	Link          string    `json:"link"`
	FaviconUrl    string    `json:"faviconUrl"`
	Tags          []string  `json:"tags"`
	SubmitterId   uuid.UUID `json:"submitterId"`
	Submitter     *User     `json:"submitter,omitempty"`
	AddedDate     time.Time `json:"addedDate"`
	SyncErorr     *string   `json:"syncError,omitempty"`
	etag          string
	lastFetchDate *time.Time
}

type FeedDao struct {
	Id            uuid.UUID
	Name          string
	Link          string
	FaviconUrl    string `db:"favicon_url"`
	Tags          pq.StringArray
	SubmitterId   uuid.UUID `db:"submitter_id"`
	Submitter     *User     `db:"submitter"`
	AddedDate     time.Time `db:"added_date"`
	SyncErorr     *string   `db:"sync_error"`
	Etag          string
	LastFetchDate *time.Time `db:"last_fetch_date"`
}

func (f *FeedDao) ToFeed() Feed {
	return Feed{
		Id:            f.Id,
		Name:          f.Name,
		Link:          f.Link,
		FaviconUrl:    f.FaviconUrl,
		Tags:          f.Tags,
		SubmitterId:   f.SubmitterId,
		Submitter:     f.Submitter,
		AddedDate:     f.AddedDate,
		etag:          f.Etag,
		lastFetchDate: f.LastFetchDate,
	}
}

func (f *Feed) ToDao() FeedDao {
	return FeedDao{
		Id:            f.Id,
		Name:          f.Name,
		Link:          f.Link,
		FaviconUrl:    f.FaviconUrl,
		Tags:          f.Tags,
		SubmitterId:   f.SubmitterId,
		Submitter:     f.Submitter,
		AddedDate:     f.AddedDate,
		Etag:          f.etag,
		LastFetchDate: f.lastFetchDate,
	}
}

type FeedService struct {
	database *sqlx.DB
	reader   *Reader
}

func NewFeedService(db *sqlx.DB, reader *Reader) FeedService {
	return FeedService{
		database: db,
		reader:   reader,
	}
}

func (s FeedService) GetFeedData(link string) ([]Feed, error) {
	parsed, err := s.reader.ReadFeed(link, "", nil)
	if err != nil {
		return nil, err
	}
	return []Feed{
		{
			Id:         uuid.New(),
			Name:       parsed.Title,
			Link:       link,
			FaviconUrl: fmt.Sprintf("%s/favicon.ico", parsed.Link),
			AddedDate:  time.Now(),
		},
	}, nil
}

func (s FeedService) AddFeed(feed Feed) (Feed, error) {
	_, err := s.database.NamedExec(
		`insert into feeds (id, name, link, favicon_url, tags, submitter_id, added_date, etag, last_fetch_date)
		values (:id, :name, :link, :favicon_url, :tags, :submitter_id, :added_date, :etag, :last_fetch_date)`,
		feed.ToDao(),
	)
	if err != nil {
		return Feed{}, err
	}
	return feed, nil
}

func (s FeedService) ListFeeds() ([]Feed, error) {
	ret := []FeedDao{}
	err := s.database.Select(
		&ret,
		`select f.*, u.id as "submitter.id", u.name as "submitter.name", u.email as "submitter.email", u.password as "submitter.password"
		from feeds as f left
		join users as u on u.id = f.submitter_id
		order by added_date`,
	)
	if err != nil {
		return nil, err
	}
	return Map(ret, func(f FeedDao, _ int) Feed { return f.ToFeed() }), nil
}

func (s FeedService) UpdateSyncStatus(id uuid.UUID, etag string, lastFetchDate *time.Time) error {
	_, err := s.database.NamedExec(
		`update feeds set etag = :etag, last_fetch_date = :date, sync_error = :err
		where id = :id`,
		map[string]interface{}{
			"id":   id,
			"etag": etag,
			"date": lastFetchDate,
			"err":  nil,
		},
	)
	return err
}

func (s FeedService) SaveSyncError(id uuid.UUID, error error) error {
	_, err := s.database.NamedExec(
		`update feeds set sync_error = :err
		where id = :i`,
		map[string]interface{}{
			"id":  id,
			"err": error.Error(),
		},
	)
	return err
}