package handlers

import (
	"errors"
	"slices"
	"strings"

	"gitea.tecamino.com/paadi/memberDB/models"
)

type counter struct {
	event int
	total int
}

func (dh *DatabaseHandler) GetReport(filter models.ReportFilter) (report models.Report, err error) {
	if !dh.DatabaseOpened() {
		return report, errors.New("database not opened")
	}

	if len(filter.Date) == 0 {
		return
	}

	var events []models.Event

	if len(filter.Name) > 0 {
		err = dh.database.GetByKey(&events, "name", filter.Name, true)
	} else {
		events, err = dh.GetEvent(0)
	}
	if err != nil {
		return
	}

	report.Data = make(map[string]*models.Data)

	//helper
	count := make(map[string]*counter)

	addedMember := make(map[uint]bool)

	for _, e := range events {

		var includesDate bool

		for _, d := range filter.Date {
			if strings.Contains(e.Date, d) {
				includesDate = true
			}
		}
		if !includesDate {
			continue
		}

		var data *models.Data
		if _, ok := count[e.Day]; !ok {
			count[e.Day] = &counter{}
		}
		count[e.Day].event += 1

		data, ok := report.Data[e.Day]
		if !ok {
			data = &models.Data{Minimal: len(e.Attendees)}
			report.Data[e.Day] = data
		}

		if data.Minimal > len(e.Attendees) {
			data.Minimal = len(e.Attendees)
		}

		if data.Maximal < len(e.Attendees) {
			data.Maximal = len(e.Attendees)
		}

		count[e.Day].total += len(e.Attendees)
		data.Average = count[e.Day].total / count[e.Day].event

		for _, a := range e.Attendees {
			if _, ok := addedMember[a.Id]; ok {
				continue
			}

			report.Attendees = append(report.Attendees, a)
			addedMember[a.Id] = true
		}
	}

	// add all member not attended
	members, err := dh.GetMember(0)
	if err != nil {
		return
	}

	for _, m := range members {
		if _, ok := addedMember[m.Id]; ok {
			continue
		} else if len(filter.Groups) > 0 {
			if m.Group == nil {
				continue
			} else if !slices.Contains(filter.Groups, m.Group.Id) {
				continue
			}
		}
		report.NonAttendees = append(report.NonAttendees, &m)
	}

	return
}