package main

import (
	"fmt"

	"github.com/google/uuid"
)

type ExtractorError struct {
	Batch
	LastId    int64
	HasLastId bool
	Msg       string
}

func (e *ExtractorError) Error() string {
	return e.Msg
}

const maxRetryAttempts = 3

func extractorErrorHandler(chErrorsIn <-chan ExtractorError, chBatchesOut chan<- Batch, chGlobalErrorsOut chan<- error) {
	for err := range chErrorsIn {
		if err.RetryCounter >= maxRetryAttempts {
			chGlobalErrorsOut <- fmt.Errorf("batch %v reached max retries (%d): %s", err.Id, maxRetryAttempts, err.Msg)
			continue
		}

		newBatch := err.Batch
		newBatch.RetryCounter++

		if err.HasLastId {
			newBatch.ParentId = err.Id
			newBatch.Id = uuid.New()
			newBatch.LowerLimit = err.LastId
			newBatch.IsLowerLimitInclusive = false
		}

		chBatchesOut <- newBatch
	}
}

func ExtractorErrorFromLastRowMssql(lastRow UnknownRowValues, indexPrimaryKey int, batch *Batch, previousError error) ExtractorError {
	lastIdRawValue := lastRow[indexPrimaryKey]

	lastId, ok := ToInt64(lastIdRawValue)
	if !ok {
		currentBatch := *batch
		currentBatch.RetryCounter = maxRetryAttempts
		exError := ExtractorError{
			Batch:     currentBatch,
			HasLastId: true,
			Msg:       fmt.Sprintf("Couldn't cast last id value as int: %s", previousError.Error()),
		}
		return exError

	}

	exError := ExtractorError{
		Batch:     *batch,
		HasLastId: true,
		LastId:    lastId,
		Msg:       previousError.Error(),
	}
	return exError
}