package queue

import (
	"context"
	"errors"
	"testing"
	"time"

	"wucher/internal/config"
	"wucher/internal/shared/pkg/logger"
)

type stubHandler struct {
	err error
}

func (h stubHandler) Handle(context.Context, *Envelope) error {
	return h.err
}

type stubIdempotencyStore struct {
	state IdempotencyState
	err   error
}

func (s stubIdempotencyStore) Acquire(context.Context, string, time.Duration) (IdempotencyState, error) {
	if s.err != nil {
		return "", s.err
	}
	if s.state != "" {
		return s.state, nil
	}
	return IdempotencyStateAcquired, nil
}

func (s stubIdempotencyStore) MarkCompleted(context.Context, string, time.Duration) error {
	return nil
}

func (s stubIdempotencyStore) Release(context.Context, string) error {
	return nil
}

func TestWorkerProcessDeliveryDuplicate(t *testing.T) {
	worker := NewWorker(WorkerConfig{}, nil, NewJSONSerializer("v1", true, QueueTypeStandard, ""), stubHandler{}, nil, stubIdempotencyStore{state: IdempotencyStateDuplicate}, nil, nil, logger.New(config.LoggingConfig{Format: "json"}))
	message, err := NewJSONSerializer("v1", true, QueueTypeStandard, "").Serialize(context.Background(), EmailJob{
		To:      "user@example.com",
		Subject: "Hello",
		Body:    "World",
	})
	if err != nil {
		t.Fatalf("serialize: %v", err)
	}

	result := worker.processDelivery(context.Background(), &Delivery{ID: message.ID, Body: message.Body, Attributes: message.Attributes, ReceiveCount: 1})
	if result.decision.Action != RetryActionAck {
		t.Fatalf("expected ack decision, got %s", result.decision.Action)
	}
	if worker.Metrics().Snapshot().Duplicates != 1 {
		t.Fatalf("expected duplicate metric to increment")
	}
}

func TestWorkerProcessDeliveryMalformedPayload(t *testing.T) {
	worker := NewWorker(WorkerConfig{}, nil, NewJSONSerializer("v1", false, QueueTypeStandard, ""), stubHandler{}, nil, stubIdempotencyStore{}, nil, nil, logger.New(config.LoggingConfig{Format: "json"}))
	result := worker.processDelivery(context.Background(), &Delivery{ID: "msg-1", Body: []byte(`{"bad":true}`), ReceiveCount: 1})
	if result.decision.Action != RetryActionDeadLetter {
		t.Fatalf("expected dead-letter decision, got %s", result.decision.Action)
	}
	if worker.Metrics().Snapshot().Malformed != 1 {
		t.Fatalf("expected malformed metric to increment")
	}
}

func TestWorkerProcessDeliveryTransientError(t *testing.T) {
	worker := NewWorker(WorkerConfig{}, nil, NewJSONSerializer("v1", true, QueueTypeStandard, ""), stubHandler{err: Transient(errors.New("ses timeout"))}, nil, stubIdempotencyStore{}, nil, nil, logger.New(config.LoggingConfig{Format: "json"}))
	message, err := NewJSONSerializer("v1", true, QueueTypeStandard, "").Serialize(context.Background(), EmailJob{
		To:      "user@example.com",
		Subject: "Hello",
		Body:    "World",
	})
	if err != nil {
		t.Fatalf("serialize: %v", err)
	}

	result := worker.processDelivery(context.Background(), &Delivery{ID: message.ID, Body: message.Body, Attributes: message.Attributes, ReceiveCount: 2})
	if result.decision.Action != RetryActionRetry {
		t.Fatalf("expected retry decision, got %s", result.decision.Action)
	}
	if result.decision.Delay <= 0 {
		t.Fatalf("expected positive retry delay")
	}
}