package growth

import (
	"slices"
	"time"
)

type Session struct {
	CreatedAt  time.Time `json:"createdAt"`
	Status     string    `json:"status"`
	AmountRial int64     `json:"amountRial"`
}

// AggregateDaily groups already-authorized, scope-filtered sessions by Tehran
// local day. Paid and Verified are the only successful bank-payment statuses.
func AggregateDaily(sessions []Session, catalog []Event) []DailyPoint {
	byDate := make(map[string]DailyPoint)
	for _, session := range sessions {
		local := session.CreatedAt.In(tehranLocation())
		date := time.Date(local.Year(), local.Month(), local.Day(), 0, 0, 0, 0, tehranLocation())
		key := dayKey(date)
		point := byDate[key]
		point.Date = date
		point.SessionCount++
		if session.Status == "Paid" || session.Status == "Verified" {
			point.PaidSessionCount++
			point.PaidAmountRial += session.AmountRial
		}
		byDate[key] = point
	}
	points := make([]DailyPoint, 0, len(byDate))
	for _, point := range byDate {
		for _, event := range catalog {
			if !dateBefore(point.Date, event.StartDate) && !dateAfter(point.Date, event.EndDate) {
				point.EventIDs = append(point.EventIDs, event.ID)
			}
		}
		slices.Sort(point.EventIDs)
		points = append(points, point)
	}
	slices.SortFunc(points, func(a, b DailyPoint) int { return a.Date.Compare(b.Date) })
	return points
}