package sqlite

import (
	"database/sql/driver"
	"time"

	"github.com/stashapp/stash/pkg/models"
)

const sqliteDateLayout = "2006-01-02"

// Date represents a date stored as "YYYY-MM-DD"
type Date struct {
	Date time.Time
}

// Scan implements the Scanner interface.
func (d *Date) Scan(value interface{}) error {
	d.Date = value.(time.Time)
	return nil
}

// Value implements the driver Valuer interface.
func (d Date) Value() (driver.Value, error) {
	return d.Date.Format(sqliteDateLayout), nil
}

// NullDate represents a nullable date stored as "YYYY-MM-DD"
type NullDate struct {
	Date  time.Time
	Valid bool
}

// Scan implements the Scanner interface.
func (d *NullDate) Scan(value interface{}) error {
	var ok bool
	d.Date, ok = value.(time.Time)
	if !ok {
		d.Date = time.Time{}
		d.Valid = false
		return nil
	}

	// Zero dates, which primarily come from empty strings in the DB, are treated as being invalid.
	// TODO: add migration to remove invalid dates from the database and remove this.
	// Ensure elsewhere that empty date inputs resolve to a null date and not a zero date.
	// Zero dates shouldn't be invalid.
	if d.Date.IsZero() {
		d.Valid = false
	} else {
		d.Valid = true
	}

	return nil
}

// Value implements the driver Valuer interface.
func (d NullDate) Value() (driver.Value, error) {
	// TODO: don't ignore zero value, as above
	if !d.Valid || d.Date.IsZero() {
		return nil, nil
	}

	return d.Date.Format(sqliteDateLayout), nil
}

func (d *NullDate) DatePtr() *models.Date {
	if d == nil || !d.Valid {
		return nil
	}

	return &models.Date{Time: d.Date}
}

func NullDateFromDatePtr(d *models.Date) NullDate {
	if d == nil {
		return NullDate{Valid: false}
	}
	return NullDate{Date: d.Time, Valid: true}
}