package edgeutils

import (
	"fmt"
	"regexp"
	"time"
)

func IsValidTimestamp(time string) error {
	// ISO 8601 regex
	validRegex := "^(-?(?:[1-9][0-9]*)?[0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])(?:T|\\s)(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])?(Z)?$"
	compiledRegex := regexp.MustCompile(validRegex)

	if !compiledRegex.MatchString(time) {
		return fmt.Errorf("Timestamp %s is not a valid Timestamp", time)
	}
	return nil
}

func TimeSequenceCheck(start string, end string) error {
	// EX: 2024-04-25T15:34:12Z
	timeInputStart, err := time.Parse(time.RFC3339, start)
	if err != nil {
		return fmt.Errorf("Start Timestamp %s was not able to be parsed as a Time Object", start)
	}

	timeInputEnd, err := time.Parse(time.RFC3339, end)
	if err != nil {
		return fmt.Errorf("End Timestamp %s was not able to be parsed as a Time Object", end)
	}

	if timeInputEnd.Before(timeInputStart) {
		return fmt.Errorf("End Timestamp %s comes before the start time %s", end, start)
	}
	return nil
}

func ConvertToRFC3339(timeInput string) (string, error) {
	// input := "2024-05-01T08:04:12-04:00"
	loc, _ := time.LoadLocation("UTC")
	expected, err := time.Parse(time.RFC3339, timeInput)
	if err != nil {
		return "", fmt.Errorf("Date Formatting Error: %w", err)
	}
	res := expected.In(loc)

	newRes := res.Format(time.RFC3339)

	return newRes, nil
}