package services

import (
	"context"
	"github.com/gisle/stufflog/database"
	"github.com/gisle/stufflog/models"
	"github.com/gisle/stufflog/slerrors"
	"time"
)

// ScoringService scores activities. It cares not for users.
type ScoringService struct {
	db database.Database
}

func (s *ScoringService) ScoreOne(ctx context.Context, period models.Period, log models.PeriodLog) (*models.Score, error) {
	return s.scoreOne(ctx, period, log)
}

func (s *ScoringService) scoreOne(ctx context.Context, period models.Period, log models.PeriodLog) (*models.Score, error) {
	goal := period.Goal(log.GoalID)
	if goal == nil {
		return nil, slerrors.NotFound("Goal")
	}

	activity, err := s.db.Activities().FindID(ctx, goal.ActivityID)
	if err != nil || activity.UserID != period.UserID {
		return nil, slerrors.NotFound("Goal's Activity")
	}
	subActivity := activity.SubActivity(log.SubActivityID)
	if subActivity == nil {
		return nil, slerrors.NotFound("Goal's Sub-Activity")
	}

	score := models.Score{
		ActivityScore: subActivity.Value,
		Amount:        log.Amount,
	}

	if log.SubGoalID != "" {
		subGoal := goal.SubGoal(log.SubGoalID)
		if subGoal == nil {
			return nil, slerrors.NotFound("Sub-Goal")
		}

		multiplier := subGoal.Multiplier
		score.SubGoalMultiplier = &multiplier
	}

	if activity.DailyBonus > 0 {
		isFirst := true
		for _, log2 := range period.Logs {
			if log2.Date.Local().Truncate(time.Hour*24) != log.Date.Local().Truncate(time.Hour*24) {
				continue
			}

			if log2.ID == log.ID {
				break
			}
			if log2.GoalID == log.GoalID {
				isFirst = false
				break
			}
		}

		if isFirst {
			score.DailyBonus = activity.DailyBonus
		}
	}

	score.Calc()

	return &score, nil
}

func (s *ScoringService) ScoreAll(ctx context.Context, period models.Period) (*models.Period, error) {
	period = *period.Copy()

	for i, log := range period.Logs {
		score, err := s.scoreOne(ctx, period, log)
		if err != nil {
			return nil, err
		}

		period.Logs[i].Score = score
	}

	err := s.db.Periods().Insert(ctx, period)
	if err != nil {
		return nil, err
	}

	return &period, nil
}

func NewScoringService(db database.Database) *ScoringService {
	return &ScoringService{db: db}
}