package cloudwatch

import (
	"fmt"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/service/cloudwatch"
	"github.com/grafana/grafana/pkg/tsdb"
)

func (e *CloudWatchExecutor) buildMetricDataInput(queryContext *tsdb.TsdbQuery, queries map[string]*cloudWatchQuery) (*cloudwatch.GetMetricDataInput, error) {
	startTime, err := queryContext.TimeRange.ParseFrom()
	if err != nil {
		return nil, err
	}

	endTime, err := queryContext.TimeRange.ParseTo()
	if err != nil {
		return nil, err
	}

	if !startTime.Before(endTime) {
		return nil, fmt.Errorf("Invalid time range: Start time must be before end time")
	}

	metricDataInput := &cloudwatch.GetMetricDataInput{
		StartTime: aws.Time(startTime),
		EndTime:   aws.Time(endTime),
		ScanBy:    aws.String("TimestampAscending"),
	}
	for _, query := range queries {
		metricDataQuery, err := e.buildMetricDataQuery(query)
		if err != nil {
			return nil, &queryError{err, query.RefId}
		}
		metricDataInput.MetricDataQueries = append(metricDataInput.MetricDataQueries, metricDataQuery)
	}

	return metricDataInput, nil
}