package server

import (
	"net/http"
	"net/http/httptest"
	"os"

	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"
)

var _ = Describe("middlewares", func() {
	var nextCalled bool
	next := func(w http.ResponseWriter, r *http.Request) {
		nextCalled = true
	}
	Describe("robotsTXT", func() {
		BeforeEach(func() {
			nextCalled = false
		})

		It("returns the robot.txt when requested from root", func() {
			r := httptest.NewRequest("GET", "/robots.txt", nil)
			w := httptest.NewRecorder()

			robotsTXT(os.DirFS("tests/fixtures"))(http.HandlerFunc(next)).ServeHTTP(w, r)

			Expect(nextCalled).To(BeFalse())
			Expect(w.Body.String()).To(HavePrefix("User-agent:"))
		})

		It("allows prefixes", func() {
			r := httptest.NewRequest("GET", "/app/robots.txt", nil)
			w := httptest.NewRecorder()

			robotsTXT(os.DirFS("tests/fixtures"))(http.HandlerFunc(next)).ServeHTTP(w, r)

			Expect(nextCalled).To(BeFalse())
			Expect(w.Body.String()).To(HavePrefix("User-agent:"))
		})

		It("passes through requests for other files", func() {
			r := httptest.NewRequest("GET", "/this_is_not_a_robots.txt_file", nil)
			w := httptest.NewRecorder()

			robotsTXT(os.DirFS("tests/fixtures"))(http.HandlerFunc(next)).ServeHTTP(w, r)

			Expect(nextCalled).To(BeTrue())
		})
	})

	Describe("serverAddressMiddleware", func() {
		var (
			nextHandler http.Handler
			middleware  http.Handler
			recorder    *httptest.ResponseRecorder
			req         *http.Request
		)

		BeforeEach(func() {
			nextHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				w.WriteHeader(http.StatusOK)
			})
			middleware = serverAddressMiddleware(nextHandler)
			recorder = httptest.NewRecorder()
		})

		Context("with no X-Forwarded headers", func() {
			BeforeEach(func() {
				req, _ = http.NewRequest("GET", "http://example.com", nil)
			})

			It("should not modify the request", func() {
				middleware.ServeHTTP(recorder, req)
				Expect(req.Host).To(Equal("example.com"))
				Expect(req.URL.Scheme).To(Equal("http"))
			})
		})

		Context("with X-Forwarded-Host header", func() {
			BeforeEach(func() {
				req, _ = http.NewRequest("GET", "http://example.com", nil)
				req.Header.Set("X-Forwarded-Host", "forwarded.example.com")
			})

			It("should modify the request with the X-Forwarded-Host header value", func() {
				middleware.ServeHTTP(recorder, req)
				Expect(req.Host).To(Equal("forwarded.example.com"))
				Expect(req.URL.Scheme).To(Equal("http"))
			})
		})

		Context("with X-Forwarded-Proto header", func() {
			BeforeEach(func() {
				req, _ = http.NewRequest("GET", "http://example.com", nil)
				req.Header.Set("X-Forwarded-Proto", "https")
			})

			It("should modify the request with the X-Forwarded-Proto header value", func() {
				middleware.ServeHTTP(recorder, req)
				Expect(req.Host).To(Equal("example.com"))
				Expect(req.URL.Scheme).To(Equal("https"))
			})
		})

		Context("with X-Forwarded-Scheme header", func() {
			BeforeEach(func() {
				req, _ = http.NewRequest("GET", "http://example.com", nil)
				req.Header.Set("X-Forwarded-Scheme", "https")
			})

			It("should modify the request with the X-Forwarded-Scheme header value", func() {
				middleware.ServeHTTP(recorder, req)
				Expect(req.Host).To(Equal("example.com"))
				Expect(req.URL.Scheme).To(Equal("https"))
			})
		})

		Context("with multiple X-Forwarded headers", func() {
			BeforeEach(func() {
				req, _ = http.NewRequest("GET", "http://example.com", nil)
				req.Header.Set("X-Forwarded-Host", "forwarded.example.com")
				req.Header.Set("X-Forwarded-Proto", "https")
				req.Header.Set("X-Forwarded-Scheme", "http")
			})

			It("should modify the request with the first non-empty X-Forwarded header value", func() {
				middleware.ServeHTTP(recorder, req)
				Expect(req.Host).To(Equal("forwarded.example.com"))
				Expect(req.URL.Scheme).To(Equal("https"))
			})
		})

		Context("with multiple values in X-Forwarded-Host header", func() {
			BeforeEach(func() {
				req, _ = http.NewRequest("GET", "http://example.com", nil)
				req.Header.Set("X-Forwarded-Host", "forwarded1.example.com, forwarded2.example.com")
			})

			It("should modify the request with the first value in X-Forwarded-Host header", func() {
				middleware.ServeHTTP(recorder, req)
				Expect(req.Host).To(Equal("forwarded1.example.com"))
				Expect(req.URL.Scheme).To(Equal("http"))
			})
		})
	})
})