package cors

import (
	"bufio"
	"net"
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestCorsHandlerWithOrigins(t *testing.T) {
	tests := []struct {
		name      string
		origins   []string
		reqOrigin string
		expect    string
	}{
		{
			name:   "allow all origins",
			expect: allOrigins,
		},
		{
			name:      "allow one origin",
			origins:   []string{"http://local"},
			reqOrigin: "http://local",
			expect:    "http://local",
		},
		{
			name:      "allow many origins",
			origins:   []string{"http://local", "http://remote"},
			reqOrigin: "http://local",
			expect:    "http://local",
		},
		{
			name:      "allow all origins",
			reqOrigin: "http://local",
			expect:    "*",
		},
		{
			name:      "allow many origins with all mark",
			origins:   []string{"http://local", "http://remote", "*"},
			reqOrigin: "http://another",
			expect:    "http://another",
		},
		{
			name:      "not allow origin",
			origins:   []string{"http://local", "http://remote"},
			reqOrigin: "http://another",
		},
	}

	methods := []string{
		http.MethodOptions,
		http.MethodGet,
		http.MethodPost,
	}

	for _, test := range tests {
		for _, method := range methods {
			test := test
			t.Run(test.name+"-handler", func(t *testing.T) {
				r := httptest.NewRequest(method, "http://localhost", nil)
				r.Header.Set(originHeader, test.reqOrigin)
				w := httptest.NewRecorder()
				handler := NotAllowedHandler(nil, test.origins...)
				handler.ServeHTTP(w, r)
				if method == http.MethodOptions {
					assert.Equal(t, http.StatusNoContent, w.Result().StatusCode)
				} else {
					assert.Equal(t, http.StatusNotFound, w.Result().StatusCode)
				}
				assert.Equal(t, test.expect, w.Header().Get(allowOrigin))
			})
			t.Run(test.name+"-handler-custom", func(t *testing.T) {
				r := httptest.NewRequest(method, "http://localhost", nil)
				r.Header.Set(originHeader, test.reqOrigin)
				w := httptest.NewRecorder()
				handler := NotAllowedHandler(func(w http.ResponseWriter) {
					w.Header().Set("foo", "bar")
				}, test.origins...)
				handler.ServeHTTP(w, r)
				if method == http.MethodOptions {
					assert.Equal(t, http.StatusNoContent, w.Result().StatusCode)
				} else {
					assert.Equal(t, http.StatusNotFound, w.Result().StatusCode)
				}
				assert.Equal(t, test.expect, w.Header().Get(allowOrigin))
				assert.Equal(t, "bar", w.Header().Get("foo"))
			})
		}
	}

	for _, test := range tests {
		for _, method := range methods {
			test := test
			t.Run(test.name+"-middleware", func(t *testing.T) {
				r := httptest.NewRequest(method, "http://localhost", nil)
				r.Header.Set(originHeader, test.reqOrigin)
				w := httptest.NewRecorder()
				handler := Middleware(nil, test.origins...)(func(w http.ResponseWriter, r *http.Request) {
					w.WriteHeader(http.StatusOK)
				})
				handler.ServeHTTP(w, r)
				if method == http.MethodOptions {
					assert.Equal(t, http.StatusNoContent, w.Result().StatusCode)
				} else {
					assert.Equal(t, http.StatusOK, w.Result().StatusCode)
				}
				assert.Equal(t, test.expect, w.Header().Get(allowOrigin))
			})
			t.Run(test.name+"-middleware-custom", func(t *testing.T) {
				r := httptest.NewRequest(method, "http://localhost", nil)
				r.Header.Set(originHeader, test.reqOrigin)
				w := httptest.NewRecorder()
				handler := Middleware(func(header http.Header) {
					header.Set("foo", "bar")
				}, test.origins...)(func(w http.ResponseWriter, r *http.Request) {
					w.WriteHeader(http.StatusOK)
				})
				handler.ServeHTTP(w, r)
				if method == http.MethodOptions {
					assert.Equal(t, http.StatusNoContent, w.Result().StatusCode)
				} else {
					assert.Equal(t, http.StatusOK, w.Result().StatusCode)
				}
				assert.Equal(t, test.expect, w.Header().Get(allowOrigin))
				assert.Equal(t, "bar", w.Header().Get("foo"))
			})
		}
	}
}

func TestGuardedResponseWriter_Flush(t *testing.T) {
	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
	handler := NotAllowedHandler(func(w http.ResponseWriter) {
		w.Header().Set("X-Test", "test")
		w.WriteHeader(http.StatusServiceUnavailable)
		_, err := w.Write([]byte("content"))
		assert.Nil(t, err)

		flusher, ok := w.(http.Flusher)
		assert.True(t, ok)
		flusher.Flush()
	}, "foo.com")

	resp := httptest.NewRecorder()
	handler.ServeHTTP(resp, req)
	assert.Equal(t, http.StatusServiceUnavailable, resp.Code)
	assert.Equal(t, "test", resp.Header().Get("X-Test"))
	assert.Equal(t, "content", resp.Body.String())
}

func TestGuardedResponseWriter_Hijack(t *testing.T) {
	resp := httptest.NewRecorder()
	writer := &guardedResponseWriter{
		w: resp,
	}
	assert.NotPanics(t, func() {
		writer.Hijack()
	})

	writer = &guardedResponseWriter{
		w: mockedHijackable{resp},
	}
	assert.NotPanics(t, func() {
		writer.Hijack()
	})
}

type mockedHijackable struct {
	*httptest.ResponseRecorder
}

func (m mockedHijackable) Hijack() (net.Conn, *bufio.ReadWriter, error) {
	return nil, nil, nil
}