package database

import (
	"strconv"
	"time"
	"velvettear/worklog/internal/log"
	"velvettear/worklog/internal/tools"

	"gorm.io/gorm"
)

// exported function(s)
func StartTimestamp(user string) (bool, Timestamp) {
	workday := GetActiveTimestamp(user)
	if workday.ID > 0 {
		log.Debug("workday for today has already been started", "id: "+strconv.Itoa(workday.ID), "started: "+tools.TimeToHHMMSS(workday.Start))
		return false, workday
	}
	workday = Timestamp{
		User:  user,
		Start: time.Now(),
	}
	result := connection.Create(&workday)
	success := true
	if result.Error != nil {
		log.Error("encountered an error starting a new workday", result.Error.Error())
		success = false
	} else if result.RowsAffected < 1 {
		log.Debug("could not start a new workday")
		success = false
	}
	return success, workday
}

func StopTimestamp(user string) (bool, Timestamp) {
	var timestamp Timestamp
	result := connection.Where("end = ? and user = ?", tools.ZeroDate, user).Last(&timestamp)
	if result.Error != nil {
		log.Error("encountered an error selecting the last workday for user '"+user+"'", result.Error.Error())
		return false, timestamp
	}
	if timestamp.ID == 0 || !timestamp.End.Equal(tools.ZeroDate) {
		log.Debug("there is no open workday for user '" + user + "' to stop")
		timestamp.ID = 0
		return false, timestamp
	}
	success := true
	timestamp.End = time.Now()
	result = connection.Save(&timestamp)
	if result.Error != nil {
		log.Error("encountered an error updating the last workday", result.Error.Error())
		success = false
	} else if result.RowsAffected < 1 {
		log.Debug("could not stop the last workday")
		success = false
	}
	return success, timestamp
}

func GetFirstTimestamp(user string, date time.Time) Timestamp {
	return GetTodaysTimestamp(user, date, true)
}

func GetLastTimestamp(user string, date time.Time) Timestamp {
	return GetTodaysTimestamp(user, date, false)
}

func GetTodaysTimestamp(user string, date time.Time, first bool) Timestamp {
	var timestamp Timestamp
	var where string
	var order string
	if first {
		date = time.Date(date.Year(), date.Month(), date.Day(), 0, 0, 0, 0, time.UTC)
		order = "asc"
		where = "start > ?"
	} else {
		date = time.Date(date.Year(), date.Month(), date.Day(), 23, 59, 59, 0, time.UTC)
		order = "desc"
		where = "start < ?"
	}
	connection.Where(where+" and user = ?", date, user).Order("start " + order).First(&timestamp)
	return timestamp
}

func GetActiveTimestamp(user string) Timestamp {
	now := time.Now()
	todayStart := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, time.UTC)
	var timestamp Timestamp
	connection.Where("start > ? and end = ? and user = ?", todayStart, tools.ZeroDate, user).First(&timestamp)
	return timestamp
}

func GetAggregatedTimestamps(from time.Time, to time.Time, user string) map[string][]Timestamp {
	var timestamps []Timestamp
	connection.Select("id", "start", "end").Where("start >= ? and end <= ? and end != ? and user = ?", from, to, tools.ZeroDate, user).Order("id desc").Find(&timestamps)
	var aggregatedTimestamps = make(map[string][]Timestamp)
	for _, timestamp := range timestamps {
		date := tools.TimeToDDMMYYYY(timestamp.Start)
		mapEntry := aggregatedTimestamps[date]
		mapEntry = append(mapEntry, timestamp)
		aggregatedTimestamps[date] = mapEntry
	}
	return aggregatedTimestamps
}

// struct(s)
type Timestamp struct {
	gorm.Model
	ID    int
	User  string
	Start time.Time
	End   time.Time
}