package testkit

import (
	"context"
	"sync"

	"galaxy/authsession/internal/domain/gatewayprojection"
	"galaxy/authsession/internal/ports"
)

// RecordingProjectionPublisher is a deterministic
// GatewaySessionProjectionPublisher double that records every published
// snapshot.
type RecordingProjectionPublisher struct {
	mu sync.Mutex

	// Err is returned directly from PublishSession when set.
	Err error

	// Errors is an optional FIFO error script consumed before Err. Nil entries
	// represent successful publish attempts.
	Errors []error

	published []gatewayprojection.Snapshot
}

// PublishSession records snapshot and returns the configured error, if any.
func (p *RecordingProjectionPublisher) PublishSession(ctx context.Context, snapshot gatewayprojection.Snapshot) error {
	if err := ctx.Err(); err != nil {
		return err
	}
	if err := snapshot.Validate(); err != nil {
		return err
	}

	p.mu.Lock()
	defer p.mu.Unlock()

	p.published = append(p.published, cloneProjectionSnapshot(snapshot))
	if len(p.Errors) > 0 {
		err := p.Errors[0]
		p.Errors = append([]error(nil), p.Errors[1:]...)
		return err
	}

	return p.Err
}

// PublishedSnapshots returns a stable snapshot of every published projection.
func (p *RecordingProjectionPublisher) PublishedSnapshots() []gatewayprojection.Snapshot {
	p.mu.Lock()
	defer p.mu.Unlock()

	snapshots := make([]gatewayprojection.Snapshot, 0, len(p.published))
	for _, snapshot := range p.published {
		snapshots = append(snapshots, cloneProjectionSnapshot(snapshot))
	}

	return snapshots
}

var _ ports.GatewaySessionProjectionPublisher = (*RecordingProjectionPublisher)(nil)