package loaders

import (
	"context"
	"errors"
	"sync"
	"sync/atomic"

	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/config"
	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/custom_errors"
	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/models"
)

func (gl *GenericLoader) Consume(
	ctx context.Context,
	tableInfo config.TargetTableInfo,
	columns []models.ColumnType,
	retryConfig config.RetryConfig,
	chBatchesIn <-chan models.Batch,
	chErrorsOut chan<- custom_errors.JobError,
	wgActiveBatches *sync.WaitGroup,
	rowsLoaded *int64,
	failedBatchesCount *int32,
) {
	colNames := mapSlice(columns, func(col models.ColumnType) string {
		return col.Name()
	})

	for {
		if ctx.Err() != nil {
			return
		}

		select {
		case <-ctx.Done():
			return
		case batch, ok := <-chBatchesIn:
			if !ok {
				return
			}

			processedRows, err := gl.ProcessBatchWithRetries(ctx, tableInfo, colNames, retryConfig, batch)
			wgActiveBatches.Done()

			if err != nil {
				atomic.AddInt32(failedBatchesCount, 1)
				if jobError, ok := errors.AsType[*custom_errors.JobError](err); ok {
					select {
					case <-ctx.Done():
						return
					case chErrorsOut <- *jobError:
					}
				} else {
					select {
					case <-ctx.Done():
						return
					case chErrorsOut <- custom_errors.JobError{ShouldCancelJob: false, Msg: err.Error(), Prev: err}:
					}
				}

				currentFBCount := atomic.LoadInt32(failedBatchesCount)
				if currentFBCount > int32(retryConfig.MaxFailedBatchesLoad) {
					select {
					case <-ctx.Done():
						return
					case chErrorsOut <- custom_errors.JobError{ShouldCancelJob: true, Msg: "Max failed batches (load) reached"}:
						return
					}
				}

				continue
			}

			atomic.AddInt64(rowsLoaded, int64(processedRows))
		}
	}
}