Move to Donetick Org, first commit

internal/chore/scheduler.go

@@ -0,0 +1,145 @@
+package chore
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/rand"
+	"strings"
+	"time"
+
+	chModel "donetick.com/core/internal/chore/model"
+)
+
+func scheduleNextDueDate(chore *chModel.Chore, completedDate time.Time) (*time.Time, error) {
+	// if Chore is rolling then the next due date calculated from the completed date, otherwise it's calculated from the due date
+	var nextDueDate time.Time
+	var baseDate time.Time
+	var frequencyMetadata chModel.FrequencyMetadata
+	err := json.Unmarshal([]byte(*chore.FrequencyMetadata), &frequencyMetadata)
+	if err != nil {
+		return nil, fmt.Errorf("error unmarshalling frequency metadata")
+	}
+	if chore.FrequencyType == "once" {
+		return nil, nil
+	}
+	if chore.NextDueDate != nil {
+		// no due date set, use the current date
+
+		baseDate = chore.NextDueDate.UTC()
+	} else {
+		baseDate = completedDate.UTC()
+	}
+	if chore.IsRolling && chore.NextDueDate.Before(completedDate) {
+		// we need to check if chore due date is before the completed date to handle this senario:
+		// if user trying to complete chore due in future (multiple time for insance) due date will be calculated
+		//  from the last completed date and due date change only in seconds.
+		// this make sure that the due date is always in future if the chore is rolling
+
+		baseDate = completedDate.UTC()
+	}
+
+	if chore.FrequencyType == "daily" {
+		nextDueDate = baseDate.AddDate(0, 0, 1)
+	} else if chore.FrequencyType == "weekly" {
+		nextDueDate = baseDate.AddDate(0, 0, 7)
+	} else if chore.FrequencyType == "monthly" {
+		nextDueDate = baseDate.AddDate(0, 1, 0)
+	} else if chore.FrequencyType == "yearly" {
+		nextDueDate = baseDate.AddDate(1, 0, 0)
+	} else if chore.FrequencyType == "adaptive" {
+		// TODO: calculate next due date based on the history of the chore
+		// calculate the difference between the due date and now in days:
+		diff := completedDate.UTC().Sub(chore.NextDueDate.UTC())
+		nextDueDate = completedDate.UTC().Add(diff)
+	} else if chore.FrequencyType == "once" {
+		// if the chore is a one-time chore, then the next due date is nil
+	} else if chore.FrequencyType == "interval" {
+		// calculate the difference between the due date and now in days:
+		if *frequencyMetadata.Unit == "hours" {
+			nextDueDate = baseDate.UTC().Add(time.Hour * time.Duration(chore.Frequency))
+		} else if *frequencyMetadata.Unit == "days" {
+			nextDueDate = baseDate.UTC().AddDate(0, 0, chore.Frequency)
+		} else if *frequencyMetadata.Unit == "weeks" {
+			nextDueDate = baseDate.UTC().AddDate(0, 0, chore.Frequency*7)
+		} else if *frequencyMetadata.Unit == "months" {
+			nextDueDate = baseDate.UTC().AddDate(0, chore.Frequency, 0)
+		} else if *frequencyMetadata.Unit == "years" {
+			nextDueDate = baseDate.UTC().AddDate(chore.Frequency, 0, 0)
+		} else {
+
+			return nil, fmt.Errorf("invalid frequency unit, cannot calculate next due date")
+		}
+	} else if chore.FrequencyType == "days_of_the_week" {
+		// TODO : this logic is bad, need to be refactored and be better.
+		// coding at night is almost  always bad idea.
+		// calculate the difference between the due date and now in days:
+		var frequencyMetadata chModel.FrequencyMetadata
+		err := json.Unmarshal([]byte(*chore.FrequencyMetadata), &frequencyMetadata)
+		if err != nil {
+
+			return nil, fmt.Errorf("error unmarshalling frequency metadata")
+		}
+		//we can only assign to days of the week that part of the frequency metadata.days
+		//it's array of days of the week, for example ["monday", "tuesday", "wednesday"]
+
+		// we need to find the next day of the week in the frequency metadata.days that we can schedule
+		// if this the last or there is only one. will use same otherwise find the next one:
+
+		// find the index of the chore day in the frequency metadata.days
+		// loop for next 7 days from the base, if the day in the frequency metadata.days then we can schedule it:
+		for i := 1; i <= 7; i++ {
+			nextDueDate = baseDate.AddDate(0, 0, i)
+			nextDay := strings.ToLower(nextDueDate.Weekday().String())
+			for _, day := range frequencyMetadata.Days {
+				if strings.ToLower(*day) == nextDay {
+					nextDate := nextDueDate.UTC()
+					return &nextDate, nil
+				}
+			}
+		}
+	} else if chore.FrequencyType == "day_of_the_month" {
+		var frequencyMetadata chModel.FrequencyMetadata
+		err := json.Unmarshal([]byte(*chore.FrequencyMetadata), &frequencyMetadata)
+		if err != nil {
+
+			return nil, fmt.Errorf("error unmarshalling frequency metadata")
+		}
+
+		for i := 1; i <= 12; i++ {
+			nextDueDate = baseDate.AddDate(0, i, 0)
+			// set the date to the first day of the month:
+			nextDueDate = time.Date(nextDueDate.Year(), nextDueDate.Month(), chore.Frequency, nextDueDate.Hour(), nextDueDate.Minute(), 0, 0, nextDueDate.Location())
+			nextMonth := strings.ToLower(nextDueDate.Month().String())
+			for _, month := range frequencyMetadata.Months {
+				if *month == nextMonth {
+					nextDate := nextDueDate.UTC()
+					return &nextDate, nil
+				}
+			}
+		}
+	} else if chore.FrequencyType == "no_repeat" {
+		return nil, nil
+	} else if chore.FrequencyType == "trigger" {
+		// if the chore is a trigger chore, then the next due date is nil
+		return nil, nil
+	} else {
+		return nil, fmt.Errorf("invalid frequency type, cannot calculate next due date")
+	}
+	return &nextDueDate, nil
+
+}
+
+func RemoveAssigneeAndReassign(chore *chModel.Chore, userID int) {
+	for i, assignee := range chore.Assignees {
+		if assignee.UserID == userID {
+			chore.Assignees = append(chore.Assignees[:i], chore.Assignees[i+1:]...)
+			break
+		}
+	}
+	if len(chore.Assignees) == 0 {
+		chore.AssignedTo = chore.CreatedBy
+	} else {
+		chore.AssignedTo = chore.Assignees[rand.Intn(len(chore.Assignees))].UserID
+	}
+	chore.UpdatedAt = time.Now()
+}