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"
	"log"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

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

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

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

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

func newEditArticleBodyTestRepo() *mockArticleRepo {
	repo := newMockArticleRepo()
	repo.articles[1] = domainArticle.Article{ID: 1, Title: "Backyard Renovation Update", Body: "Old body text", IsOnline: true}
	repo.articles[2] = domainArticle.Article{ID: 2, Title: "Draft: Kitchen Remodel", Body: "Draft notes", IsOnline: false}
	return repo
}

func setEditArticleBodyJwtCookie(t *testing.T, req *http.Request, token *jwtauth.JWTAuth) {
	t.Helper()
	_, tokenString, err := token.Encode(map[string]any{"user_id": uint32(1)})
	if err != nil {
		t.Fatalf("failed to encode jwt: %v", err)
	}
	req.AddCookie(&http.Cookie{Name: "jwt", Value: tokenString})
}

func newEditArticleBodyRequest(method, target string, body string) *http.Request {
	return httptest.NewRequest(method, target, bytes.NewBufferString(body))
}

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

	t.Run("Editing an existing article's body updates only the body", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/1", `{"body": "New body text"}`)
		setEditArticleBodyJwtCookie(t, req, token)
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusOK {
			t.Fatalf("expected status 200, got %d", rec.Code)
		}
		var got domainArticle.Article
		if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
			t.Fatalf("failed to decode response: %v", err)
		}
		if got.ID != 1 || got.Body != "New body text" || got.Title != "Backyard Renovation Update" || !got.IsOnline {
			t.Errorf("unexpected article: %+v", got)
		}
		stored := repo.articles[1]
		if stored.Body != "New body text" || stored.Title != "Backyard Renovation Update" || !stored.IsOnline {
			t.Errorf("unexpected stored article: %+v", stored)
		}
	})

	t.Run("Editing an offline article's body leaves it offline", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/2", `{"body": "Revised draft notes"}`)
		setEditArticleBodyJwtCookie(t, req, token)
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusOK {
			t.Fatalf("expected status 200, got %d", rec.Code)
		}
		var got domainArticle.Article
		if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
			t.Fatalf("failed to decode response: %v", err)
		}
		if got.ID != 2 || got.Body != "Revised draft notes" || got.IsOnline {
			t.Errorf("unexpected article: %+v", got)
		}
	})

	t.Run("Editing an unknown article answers 404", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/9999", `{"body": "New body text"}`)
		setEditArticleBodyJwtCookie(t, req, token)
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusNotFound {
			t.Fatalf("expected status 404, got %d", rec.Code)
		}
		if rec.Body.String() != apperr.ArticleNotFoundErrorMessage+"\n" {
			t.Errorf("unexpected body: %q", rec.Body.String())
		}
	})

	t.Run("A malformed id answers 400 before any repository call", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/not-a-number", `{"body": "New body text"}`)
		setEditArticleBodyJwtCookie(t, req, token)
		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.IdUint32ErrorMessage+"\n" {
			t.Errorf("unexpected body: %q", rec.Body.String())
		}
	})

	t.Run("A non-JSON request body answers 400 with the body error message", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/1", `not valid json`)
		setEditArticleBodyJwtCookie(t, req, token)
		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.BodyErrorMessage+"\n" {
			t.Errorf("unexpected body: %q", rec.Body.String())
		}
	})

	validationCases := []struct {
		name    string
		payload string
	}{
		{"empty body", `{"body": ""}`},
		{"body over 10000 characters", `{"body": "` + strings.Repeat("a", 10001) + `"}`},
	}
	for _, tc := range validationCases {
		t.Run("A body value that fails validation answers 400: "+tc.name, func(t *testing.T) {
			repo := newEditArticleBodyTestRepo()
			router := newEditArticleBodyRouter(repo, token)
			req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/1", tc.payload)
			setEditArticleBodyJwtCookie(t, req, token)
			rec := httptest.NewRecorder()
			router.ServeHTTP(rec, req)

			if rec.Code != http.StatusBadRequest {
				t.Fatalf("expected status 400, got %d", rec.Code)
			}
			if repo.articles[1].Body != "Old body text" {
				t.Errorf("expected stored body to be unchanged, got %q", repo.articles[1].Body)
			}
		})
	}

	t.Run("A response write failure is logged", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/1", `{"body": "New body text"}`)
		setEditArticleBodyJwtCookie(t, req, token)

		var logOutput bytes.Buffer
		defaultLogOutput := log.Writer()
		log.SetOutput(&logOutput)
		defer log.SetOutput(defaultLogOutput)

		router.ServeHTTP(&erroringResponseWriter{}, req)

		if !strings.Contains(logOutput.String(), "Failed to write response") {
			t.Errorf("expected the write failure to be logged, got %q", logOutput.String())
		}
	})

	t.Run("Editing an article requires authentication", func(t *testing.T) {
		repo := newEditArticleBodyTestRepo()
		router := newEditArticleBodyRouter(repo, token)
		req := newEditArticleBodyRequest(http.MethodPatch, "/v1/article/1", `{"body": "New body text"}`)
		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, req)

		if rec.Code != http.StatusUnauthorized {
			t.Fatalf("expected status 401, got %d", rec.Code)
		}
	})
}