package history

import (
	"context"
	"database/sql"
	"time"

	"reanimator/internal/idgen"
)

type FailureProjectionInput struct {
	Source      string
	ExternalID  string
	PartID      string
	MachineID   *string
	FailureType string
	FailureTime time.Time
	Details     *string
}

func (s *Service) UpsertFailureProjectionWithTx(ctx context.Context, tx *sql.Tx, in FailureProjectionInput) error {
	if tx == nil {
		return ErrConflict
	}
	var existingID string
	err := tx.QueryRowContext(ctx, `
		SELECT id
		FROM failure_events
		WHERE source = ?
		  AND part_id = ?
		  AND ((machine_id IS NULL AND ? IS NULL) OR machine_id = ?)
		  AND failure_type = ?
		  AND failure_time = ?
		  AND COALESCE(details, '') = COALESCE(?, '')
		LIMIT 1`,
		in.Source,
		in.PartID,
		in.MachineID,
		in.MachineID,
		in.FailureType,
		in.FailureTime.UTC(),
		in.Details,
	).Scan(&existingID)
	if err == nil {
		return nil
	}
	if err != sql.ErrNoRows {
		return err
	}

	id, err := s.generateID(ctx, tx, idgen.FailureEvent)
	if err != nil {
		return err
	}
	_, err = tx.ExecContext(ctx, `
		INSERT INTO failure_events (id, source, external_id, part_id, machine_id, failure_type, failure_time, details)
		VALUES (?, ?, ?, ?, ?, ?, ?, ?)
		ON DUPLICATE KEY UPDATE
			part_id = VALUES(part_id),
			machine_id = VALUES(machine_id),
			failure_type = VALUES(failure_type),
			failure_time = VALUES(failure_time),
			details = VALUES(details)`,
		id, in.Source, in.ExternalID, in.PartID, in.MachineID, in.FailureType, in.FailureTime.UTC(), in.Details,
	)
	return err
}