package test

import (
	"RenewCMS/api/handlers/article"
	"RenewCMS/api/middleware"
	"RenewCMS/api/pkg/apperr"
	validator "RenewCMS/api/pkg/validator"
	domainArticle "RenewCMS/internal/domain/article"
	"RenewCMS/internal/infrastructure/useCases"
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"net/http/httptest"
	"reflect"
	"strings"
	"testing"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/jwtauth/v5"
)

func newArticleTitleRulesRouter(repo *mockArticleRepo, token *jwtauth.JWTAuth) *chi.Mux {
	userRepo := newVerifiedUserRepo()
	getUserUseCase := useCases.NewGetUserUseCase(userRepo)

	articleHandler := article.NewHandler(
		useCases.NewCreateArticleUseCase(repo, &fakeBodyRenderer{}, discardRecorder, plainSites(), plainAuthors()),
		useCases.NewGetArticleUseCase(repo, &fakeBodyRenderer{}),
		useCases.NewListArticlesUseCase(repo, &fakeBodyRenderer{}, plainSites()),
		useCases.NewDeleteArticleUseCase(repo, discardRecorder),
		useCases.NewUpdateArticleUseCase(repo, &fakeBodyRenderer{}, discardRecorder, plainSites(), plainAuthors(), newMockImageRepo()),
		getUserUseCase,
	)

	r := chi.NewRouter()
	r.Route("/v1", func(r chi.Router) {
		r.Group(func(r chi.Router) {
			r.Use(jwtauth.Verifier(token))
			r.Use(jwtauth.Authenticator(token))
			r.Use(middleware.RequireVerifiedUser(getUserUseCase))
			r.Route("/article", func(r chi.Router) {
				r.Post("/", articleHandler.PostArticle)
			})
		})
	})
	return r
}

func postArticleRequest(t *testing.T, token *jwtauth.JWTAuth, title string, body string) *http.Request {
	t.Helper()
	payload, err := json.Marshal(map[string]string{"title": title, "body": body})
	if err != nil {
		t.Fatalf("failed to marshal body: %v", err)
	}
	req := httptest.NewRequest(http.MethodPost, "/v1/article/", bytes.NewReader(payload))
	req.Header.Set("Content-Type", "application/json")
	setJwtCookie(t, req, token, 1)
	return req
}

func TestArticleTitleTagMatchesDomainBounds(t *testing.T) {
	field, ok := reflect.TypeOf(article.PostArticle{}).FieldByName("Title")
	if !ok {
		t.Fatal("expected PostArticle to have a Title field")
	}

	expected := fmt.Sprintf("required,min=%d,max=%d", domainArticle.MinTitleRunes, domainArticle.MaxTitleRunes)
	got := field.Tag.Get("validate")
	if got != expected {
		t.Errorf("expected validate tag %q, got %q", expected, got)
	}
}

func TestArticleTitleRunesInUseCase(t *testing.T) {
	cases := []struct {
		runeCount int
		created   bool
	}{
		{2, false},
		{3, true},
		{200, true},
		{201, false},
	}

	for _, tc := range cases {
		t.Run(fmt.Sprintf("rune_count_%d", tc.runeCount), func(t *testing.T) {
			repo := newMockArticleRepo()
			uc := useCases.NewCreateArticleUseCase(repo, &fakeBodyRenderer{}, discardRecorder, plainSites(), plainAuthors())

			title := strings.Repeat("\U0001F600", tc.runeCount)
			result, err := uc.CreateArticle(testCtx, useCases.CreateArticleCommand{Title: title, Body: "Some body text"})

			if tc.created {
				if err != nil {
					t.Fatalf("expected no error, got %v", err)
				}
				if !repo.createCalled {
					t.Errorf("expected the repository's Create to have been called")
				}
				if len(repo.articles) != 1 {
					t.Errorf("expected 1 article stored, got %d", len(repo.articles))
				}
				if result.Title != title {
					t.Errorf("expected title %q, got %q", title, result.Title)
				}
			} else {
				if !errors.Is(err, domainArticle.ErrInvalidTitle) {
					t.Errorf("expected ErrInvalidTitle, got %v", err)
				}
				if repo.createCalled {
					t.Errorf("expected the repository's Create not to have been called")
				}
				if len(repo.articles) != 0 {
					t.Errorf("expected nothing stored, got %d article(s)", len(repo.articles))
				}
			}
		})
	}
}

func TestArticleTitleRunesOverHttp(t *testing.T) {
	validator.InitValidator()
	token := jwtauth.New("HS256", []byte("test-secret"), nil)

	cases := []struct {
		length  int
		status  int
		created bool
	}{
		{2, http.StatusBadRequest, false},
		{3, http.StatusCreated, true},
		{200, http.StatusCreated, true},
		{201, http.StatusBadRequest, false},
	}

	for _, tc := range cases {
		t.Run(fmt.Sprintf("length_%d", tc.length), func(t *testing.T) {
			repo := newMockArticleRepo()
			router := newArticleTitleRulesRouter(repo, token)

			title := strings.Repeat("a", tc.length)
			req := postArticleRequest(t, token, title, "Some body text")
			rec := httptest.NewRecorder()
			router.ServeHTTP(rec, req)

			if rec.Code != tc.status {
				t.Fatalf("expected status %d, got %d, body %q", tc.status, rec.Code, rec.Body.String())
			}

			if !tc.created {
				if repo.createCalled {
					t.Errorf("expected Create not to have been called")
				}
				if strings.Contains(rec.Body.String(), apperr.ArticleTitleErrorMessage) {
					t.Errorf("expected a request-layer validation error, got the domain error message: %q", rec.Body.String())
				}
				if strings.Contains(rec.Body.String(), "Failed to create article") {
					t.Errorf("expected a request-layer validation error, got the generic failure message: %q", rec.Body.String())
				}
			}

			if tc.created {
				var got domainArticle.Article
				if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
					t.Fatalf("failed to decode response: %v", err)
				}
				if got.IsOnline {
					t.Errorf("expected is_online false, got true")
				}
				if len(repo.articles) != 1 {
					t.Errorf("expected 1 article stored, got %d", len(repo.articles))
				}
			} else {
				if len(repo.articles) != 0 {
					t.Errorf("expected nothing stored, got %d article(s)", len(repo.articles))
				}
			}
		})
	}

	t.Run("A 200-rune multibyte title is accepted end to end over HTTP", func(t *testing.T) {
		repo := newMockArticleRepo()
		router := newArticleTitleRulesRouter(repo, token)

		title := strings.Repeat("\U0001F600", 200)
		req := postArticleRequest(t, token, title, "Some body text")
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusCreated {
			t.Fatalf("expected status 201, got %d, body %q", rec.Code, rec.Body.String())
		}

		var got domainArticle.Article
		if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
			t.Fatalf("failed to decode response: %v", err)
		}
		if got.Title != title {
			t.Errorf("expected title %q, got %q", title, got.Title)
		}
	})

	t.Run("The handler maps a domain title rejection to 400, not 500", func(t *testing.T) {
		repo := newMockArticleRepo()
		repo.fail.failNextWith("Create", domainArticle.ErrInvalidTitle)
		router := newArticleTitleRulesRouter(repo, token)

		req := postArticleRequest(t, token, "Valid Title", "Some body text")
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusBadRequest {
			t.Fatalf("expected status 400, got %d", rec.Code)
		}
		if rec.Body.String() != apperr.ArticleTitleErrorMessage+"\n" {
			t.Errorf("unexpected body: %q", rec.Body.String())
		}
		if strings.Contains(rec.Body.String(), "Failed to create article") {
			t.Errorf("did not expect the generic failure message, got %q", rec.Body.String())
		}
	})

	t.Run("A non-title repository failure during creation still answers 500", func(t *testing.T) {
		repo := newMockArticleRepo()
		repo.fail.failNext("Create")
		router := newArticleTitleRulesRouter(repo, token)

		req := postArticleRequest(t, token, "Valid Title", "Some body text")
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusInternalServerError {
			t.Fatalf("expected status 500, got %d", rec.Code)
		}
		if rec.Body.String() != "Failed to create article\n" {
			t.Errorf("unexpected body: %q", rec.Body.String())
		}
	})

	t.Run("POST /v1/article/ without a jwt cookie is rejected", func(t *testing.T) {
		repo := newMockArticleRepo()
		router := newArticleTitleRulesRouter(repo, token)

		payload, err := json.Marshal(map[string]string{"title": "Valid Title", "body": "Some body text"})
		if err != nil {
			t.Fatalf("failed to marshal body: %v", err)
		}
		req := httptest.NewRequest(http.MethodPost, "/v1/article/", bytes.NewReader(payload))
		req.Header.Set("Content-Type", "application/json")
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusUnauthorized {
			t.Fatalf("expected status 401, got %d", rec.Code)
		}
		if repo.createCalled {
			t.Errorf("expected Create not to have been called")
		}
	})
}