package httpapi

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
)

func TestRegisterDocumentation(t *testing.T) {
	tests := []struct {
		name            string
		path            string
		wantStatus      int
		wantContentType string
		wantBody        string
		wantLocation    string
	}{
		{
			name:            "OpenAPI document",
			path:            "/openapi.json",
			wantStatus:      http.StatusOK,
			wantContentType: "application/json",
			wantBody:        `"openapi": "3.0.3"`,
		},
		{
			name:            "Swagger UI",
			path:            "/docs/",
			wantStatus:      http.StatusOK,
			wantContentType: "text/html; charset=utf-8",
			wantBody:        `url: "/openapi.json"`,
		},
		{
			name:         "documentation trailing slash",
			path:         "/docs",
			wantStatus:   http.StatusTemporaryRedirect,
			wantLocation: "/docs/",
		},
		{
			name:       "removed Swagger route",
			path:       "/swagger/",
			wantStatus: http.StatusNotFound,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			t.Parallel()

			mux := http.NewServeMux()
			RegisterDocumentation(mux)
			request := httptest.NewRequest(http.MethodGet, tt.path, nil)
			response := httptest.NewRecorder()

			mux.ServeHTTP(response, request)

			if response.Code != tt.wantStatus {
				t.Fatalf("status = %d, want %d", response.Code, tt.wantStatus)
			}
			if tt.wantContentType != "" {
				if got := response.Header().Get("Content-Type"); got != tt.wantContentType {
					t.Errorf("Content-Type = %q, want %q", got, tt.wantContentType)
				}
			}
			if tt.wantBody != "" && !strings.Contains(response.Body.String(), tt.wantBody) {
				t.Errorf("body does not contain %q", tt.wantBody)
			}
			if got := response.Header().Get("Location"); got != tt.wantLocation {
				t.Errorf("Location = %q, want %q", got, tt.wantLocation)
			}
		})
	}
}

func TestOpenAPIDocumentCoversPublicAPI(t *testing.T) {
	t.Parallel()

	mux := http.NewServeMux()
	RegisterDocumentation(mux)
	request := httptest.NewRequest(http.MethodGet, "/openapi.json", nil)
	response := httptest.NewRecorder()
	mux.ServeHTTP(response, request)

	var document struct {
		OpenAPI string `json:"openapi"`
		Paths   map[string]map[string]struct {
			Responses map[string]json.RawMessage `json:"responses"`
		} `json:"paths"`
		Components struct {
			Schemas map[string]json.RawMessage `json:"schemas"`
		} `json:"components"`
	}
	if err := json.Unmarshal(response.Body.Bytes(), &document); err != nil {
		t.Fatalf("decode OpenAPI document: %v", err)
	}

	if document.OpenAPI != "3.0.3" {
		t.Errorf("OpenAPI version = %q, want 3.0.3", document.OpenAPI)
	}
	if _, ok := document.Paths["/health"]["get"]; !ok {
		t.Error("OpenAPI document does not define GET /health")
	}

	conversion, ok := document.Paths["/api/v1/card-to-iban"]["post"]
	if !ok {
		t.Fatal("OpenAPI document does not define POST /api/v1/card-to-iban")
	}
	for _, status := range []string{"200", "400", "405", "422", "500", "502", "503", "504"} {
		if _, ok := conversion.Responses[status]; !ok {
			t.Errorf("POST /api/v1/card-to-iban does not document response %s", status)
		}
	}
	for _, schema := range []string{
		"ConvertRequest",
		"ConvertResponse",
		"ErrorResponse",
		"HealthResponse",
	} {
		if _, ok := document.Components.Schemas[schema]; !ok {
			t.Errorf("OpenAPI document does not define schema %s", schema)
		}
	}
}