package scheduler

import (
	"context"
	"fmt"
	"strings"
	"sync"
	"sync/atomic"
	"testing"
	"time"
)

func TestSchedulerCreation(t *testing.T) {
	s := New()
	if s == nil {
		t.Fatal("New() returned nil")
	}
}

func TestSchedulerWithTimezone(t *testing.T) {
	s := New(WithTimezone("America/New_York"))
	if s == nil {
		t.Fatal("New() with timezone returned nil")
	}
}

func TestJobRegistration(t *testing.T) {
	s := New()

	job := &Job{
		Name:     "test-registration",
		Schedule: "0 * * * *",
		Handler:  func(_ context.Context) error { return nil },
	}

	if err := s.Register(job); err != nil {
		t.Fatalf("failed to register valid job: %v", err)
	}

	// Registering duplicate name should fail
	if err := s.Register(job); err == nil {
		t.Error("expected error when registering duplicate job name")
	}
}

func TestSchedulerStartStop(t *testing.T) {
	s := New()

	var runCount atomic.Int32
	job := &Job{
		Name:     "test-start-stop",
		Schedule: "* * * * * *", // Every second (6-field format)
		Handler: func(_ context.Context) error {
			runCount.Add(1)
			return nil
		},
	}

	if err := s.Register(job); err != nil {
		t.Fatalf("failed to register job: %v", err)
	}

	// Start scheduler
	if err := s.Start(); err != nil {
		t.Fatalf("failed to start scheduler: %v", err)
	}

	// Let it run for 2.5 seconds
	time.Sleep(2500 * time.Millisecond)

	// Stop scheduler
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	if err := s.Stop(ctx); err != nil {
		t.Fatalf("failed to stop scheduler: %v", err)
	}

	count := runCount.Load()
	// Should have run at least twice (at 0s and 1s, maybe 2s)
	if count < 2 {
		t.Errorf("expected job to run at least 2 times, ran %d times", count)
	}

	// Verify it stopped (count shouldn't increase)
	finalCount := count
	time.Sleep(1500 * time.Millisecond)
	if runCount.Load() != finalCount {
		t.Error("scheduler did not stop - job continued running")
	}
}

func TestSchedulerWithMiddleware(t *testing.T) {
	var executionLog []string
	var logMu sync.Mutex

	logger := &testLogger{
		onInfo: func(msg string, _ ...interface{}) {
			logMu.Lock()
			executionLog = append(executionLog, fmt.Sprintf("INFO: %s", msg))
			logMu.Unlock()
		},
		onError: func(msg string, _ ...interface{}) {
			logMu.Lock()
			executionLog = append(executionLog, fmt.Sprintf("ERROR: %s", msg))
			logMu.Unlock()
		},
	}

	s := New(WithMiddleware(
		Recovery(func(jobName string, r interface{}) {
			logMu.Lock()
			executionLog = append(executionLog, fmt.Sprintf("PANIC: %s - %v", jobName, r))
			logMu.Unlock()
		}),
		Logging(logger),
	))

	job := &Job{
		Name:     "test-middleware",
		Schedule: "* * * * * *", // Every second
		Handler: func(_ context.Context) error {
			return nil
		},
	}

	if err := s.Register(job); err != nil {
		t.Fatalf("failed to register job: %v", err)
	}

	if err := s.Start(); err != nil {
		t.Fatalf("failed to start: %v", err)
	}

	time.Sleep(1500 * time.Millisecond)

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	if err := s.Stop(ctx); err != nil {
		t.Fatalf("failed to stop: %v", err)
	}

	logMu.Lock()
	defer logMu.Unlock()

	// Should have at least one start and one completion log
	hasStart := false
	hasCompletion := false
	for _, log := range executionLog {
		if strings.Contains(log, "Job started") {
			hasStart = true
		}
		if strings.Contains(log, "Job completed") {
			hasCompletion = true
		}
	}

	if !hasStart {
		t.Error("expected job start log")
	}
	if !hasCompletion {
		t.Error("expected job completion log")
	}
}