package table_analyzers

import (
	"context"

	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/config"
	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/etl"
	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/models"
	"github.com/google/uuid"
)

func PartitionRangeGenerator(
	ctx context.Context,
	tableAnalyzer etl.TableAnalyzer,
	tableInfo config.TableInfo,
	partitionColumn string,
	rowsPerPartition int64,
	jobRange config.RangeConfig,
) ([]models.Partition, error) {
	if jobRange.Max > 0 {
		return []models.Partition{{
			Id:           uuid.New(),
			HasRange:     true,
			RetryCounter: 0,
			Range: models.PartitionRange{
				Min:            jobRange.Min,
				Max:            jobRange.Max,
				IsMinInclusive: jobRange.IsMinInclusive,
				IsMaxInclusive: jobRange.IsMaxInclusive,
			},
		}}, nil
	}

	rowsCount, err := tableAnalyzer.EstimateTotalRows(ctx, tableInfo)
	if err != nil {
		return nil, err
	}

	if rowsCount <= rowsPerPartition {
		return []models.Partition{{
			Id:           uuid.New(),
			HasRange:     false,
			RetryCounter: 0,
		}}, nil

	}

	partitionsCount := rowsCount / rowsPerPartition
	partitions, err := tableAnalyzer.CalculatePartitionRanges(ctx, tableInfo, partitionColumn, partitionsCount)
	if err != nil {
		return nil, err
	}

	return partitions, nil
}