package test

import (
	"RenewCMS/internal/domain/user"
	"RenewCMS/internal/infrastructure/useCases"
	"bytes"
	"log"
	"os"
	"strings"
	"testing"
	"time"
)

func captureRequestPasswordResetLog(t *testing.T) *bytes.Buffer {
	t.Helper()
	var buf bytes.Buffer
	log.SetOutput(&buf)
	t.Cleanup(func() { log.SetOutput(os.Stderr) })
	return &buf
}

func newRequestPasswordResetTestUserRepo() *mockUserRepo {
	repo := newMockUserRepo()
	repo.users[3] = user.User{ID: 3, Email: "alice@example.com"}
	repo.nextID = 3
	return repo
}

func TestRequestPasswordResetUseCase(t *testing.T) {
	t.Run("The use case itself hashes the code, stores it with a one-hour expiration, and sends the email", func(t *testing.T) {
		repo := newRequestPasswordResetTestUserRepo()
		mailRepo := newMockMailRepo()
		uc := useCases.NewRequestPasswordResetUseCase(repo, &stubHasher{}, mailRepo, "https://cms.example.com", discardRecorder)

		err := uc.RequestPasswordReset(testCtx, "alice@example.com")
		if err != nil {
			t.Fatalf("expected nil error, got %v", err)
		}

		if repo.updatePasswordResetCodeCalls != 1 {
			t.Fatalf("expected UpdatePasswordResetCode to be called once, got %d", repo.updatePasswordResetCodeCalls)
		}
		if repo.lastUpdatePasswordResetCodeUserId != 3 {
			t.Errorf("expected userId 3, got %d", repo.lastUpdatePasswordResetCodeUserId)
		}
		if got, want := repo.lastUpdatePasswordResetCodeExpiration, time.Now().Add(time.Hour); got.Sub(want).Abs() > 5*time.Second {
			t.Errorf("expected expiration near %v, got %v", want, got)
		}

		if len(mailRepo.SentEmails) != 1 {
			t.Fatalf("expected exactly one email, got %d", len(mailRepo.SentEmails))
		}
		sent := mailRepo.SentEmails[0]
		if sent.Address != "alice@example.com" {
			t.Errorf("expected email to alice@example.com, got %s", sent.Address)
		}
		if sent.Template != "password-reset" {
			t.Errorf("expected template password-reset, got %s", sent.Template)
		}
		data, ok := sent.Data.(useCases.MailPasswordResetData)
		if !ok {
			t.Fatalf("expected data of type MailPasswordResetData, got %T", sent.Data)
		}
		if data.Host != "https://cms.example.com" {
			t.Errorf("expected Host https://cms.example.com, got %s", data.Host)
		}
		if (&stubHasher{}).Compare(repo.lastUpdatePasswordResetCodeCode, data.VerificationCode) != nil {
			t.Errorf("expected stored hash to match the raw code sent in the email")
		}
	})

	t.Run("The use case swallows an unknown email and returns nil without touching the repository or mailer", func(t *testing.T) {
		repo := newMockUserRepo()
		mailRepo := newMockMailRepo()
		uc := useCases.NewRequestPasswordResetUseCase(repo, &stubHasher{}, mailRepo, "https://cms.example.com", discardRecorder)

		err := uc.RequestPasswordReset(testCtx, "nobody@example.com")
		if err != nil {
			t.Fatalf("expected nil error, got %v", err)
		}
		if repo.updatePasswordResetCodeCalls != 0 {
			t.Errorf("expected UpdatePasswordResetCode to never be called, got %d calls", repo.updatePasswordResetCodeCalls)
		}
		if len(mailRepo.SentEmails) != 0 {
			t.Errorf("expected no email to be sent, got %d", len(mailRepo.SentEmails))
		}
	})

	t.Run("The use case swallows a mail repository failure and still returns nil", func(t *testing.T) {
		repo := newRequestPasswordResetTestUserRepo()
		mailRepo := newMockMailRepo()
		mailRepo.fail.failNext("Send")
		uc := useCases.NewRequestPasswordResetUseCase(repo, &stubHasher{}, mailRepo, "https://cms.example.com", discardRecorder)
		logBuf := captureRequestPasswordResetLog(t)

		err := uc.RequestPasswordReset(testCtx, "alice@example.com")
		if err != nil {
			t.Fatalf("expected nil error, got %v", err)
		}
		if repo.updatePasswordResetCodeCalls != 1 {
			t.Errorf("expected UpdatePasswordResetCode to be called once, got %d", repo.updatePasswordResetCodeCalls)
		}
		if logBuf.Len() == 0 {
			t.Fatalf("expected a failure to be logged")
		}
		if !strings.Contains(strings.ToLower(logBuf.String()), "send") && !strings.Contains(strings.ToLower(logBuf.String()), "mail") {
			t.Errorf("expected the log to identify a mail-send failure, got %q", logBuf.String())
		}
	})

	t.Run("The use case logs and swallows a hashing failure", func(t *testing.T) {
		repo := newRequestPasswordResetTestUserRepo()
		mailRepo := newMockMailRepo()
		uc := useCases.NewRequestPasswordResetUseCase(repo, &stubHasher{hashErr: errStubHashFailure}, mailRepo, "https://cms.example.com", discardRecorder)
		logBuf := captureRequestPasswordResetLog(t)

		err := uc.RequestPasswordReset(testCtx, "alice@example.com")
		if err != nil {
			t.Fatalf("expected nil error, got %v", err)
		}
		if repo.updatePasswordResetCodeCalls != 0 {
			t.Errorf("expected UpdatePasswordResetCode to never be called, got %d calls", repo.updatePasswordResetCodeCalls)
		}
		if len(mailRepo.SentEmails) != 0 {
			t.Errorf("expected no email to be sent, got %d", len(mailRepo.SentEmails))
		}
		if logBuf.Len() == 0 {
			t.Fatalf("expected a failure to be logged")
		}
		if !strings.Contains(strings.ToLower(logBuf.String()), "hash") {
			t.Errorf("expected the log to identify a hashing failure, got %q", logBuf.String())
		}
	})

	t.Run("The use case logs and swallows a repository failure while storing the reset code", func(t *testing.T) {
		repo := newRequestPasswordResetTestUserRepo()
		repo.fail.failNext("UpdatePasswordResetCode")
		mailRepo := newMockMailRepo()
		uc := useCases.NewRequestPasswordResetUseCase(repo, &stubHasher{}, mailRepo, "https://cms.example.com", discardRecorder)
		logBuf := captureRequestPasswordResetLog(t)

		err := uc.RequestPasswordReset(testCtx, "alice@example.com")
		if err != nil {
			t.Fatalf("expected nil error, got %v", err)
		}
		if len(mailRepo.SentEmails) != 0 {
			t.Errorf("expected no email to be sent, got %d", len(mailRepo.SentEmails))
		}
		if logBuf.Len() == 0 {
			t.Fatalf("expected a failure to be logged")
		}
		if !strings.Contains(strings.ToLower(logBuf.String()), "updatepasswordresetcode") && !strings.Contains(strings.ToLower(logBuf.String()), "store") {
			t.Errorf("expected the log to identify a storage failure, got %q", logBuf.String())
		}
	})

	t.Run("An unverified user can request a password reset exactly like a verified one", func(t *testing.T) {
		repo := newMockUserRepo()
		repo.users[1] = user.User{ID: 1, Email: "alice@example.com", IsVerified: false}
		repo.users[2] = user.User{ID: 2, Email: "bob@example.com", IsVerified: false}
		repo.nextID = 2
		mailRepo := newMockMailRepo()
		uc := useCases.NewRequestPasswordResetUseCase(repo, &stubHasher{}, mailRepo, "https://cms.example.com", discardRecorder)

		err := uc.RequestPasswordReset(testCtx, "alice@example.com")
		if err != nil {
			t.Fatalf("expected nil error, got %v", err)
		}
		if len(mailRepo.SentEmails) != 1 {
			t.Fatalf("expected exactly one email, got %d", len(mailRepo.SentEmails))
		}
	})
}