package httpx_test

import (
	"context"
	"errors"
	"fmt"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"git.codelab.vc/pkg/httpx"
)

func TestClient_MaxResponseBody(t *testing.T) {
	t.Run("allows response within limit", func(t *testing.T) {
		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
			fmt.Fprint(w, "hello")
		}))
		defer srv.Close()

		client := httpx.New(httpx.WithMaxResponseBody(1024))
		resp, err := client.Get(context.Background(), srv.URL+"/")
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}
		body, err := resp.String()
		if err != nil {
			t.Fatalf("reading body: %v", err)
		}
		if body != "hello" {
			t.Fatalf("body = %q, want %q", body, "hello")
		}
	})

	t.Run("returns ErrResponseTooLarge when exceeding limit", func(t *testing.T) {
		largeBody := strings.Repeat("x", 1000)
		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
			fmt.Fprint(w, largeBody)
		}))
		defer srv.Close()

		client := httpx.New(httpx.WithMaxResponseBody(100))
		resp, err := client.Get(context.Background(), srv.URL+"/")
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}
		if _, err := resp.Bytes(); !errors.Is(err, httpx.ErrResponseTooLarge) {
			t.Fatalf("err = %v, want ErrResponseTooLarge", err)
		}
	})

	t.Run("allows body exactly at limit", func(t *testing.T) {
		exact := strings.Repeat("x", 100)
		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
			fmt.Fprint(w, exact)
		}))
		defer srv.Close()

		client := httpx.New(httpx.WithMaxResponseBody(100))
		resp, err := client.Get(context.Background(), srv.URL+"/")
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}
		b, err := resp.Bytes()
		if err != nil {
			t.Fatalf("reading body at exact limit: %v", err)
		}
		if len(b) != 100 {
			t.Fatalf("body length = %d, want %d", len(b), 100)
		}
	})

	t.Run("no limit when zero", func(t *testing.T) {
		largeBody := strings.Repeat("x", 10000)
		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
			fmt.Fprint(w, largeBody)
		}))
		defer srv.Close()

		client := httpx.New()
		resp, err := client.Get(context.Background(), srv.URL+"/")
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}
		b, err := resp.Bytes()
		if err != nil {
			t.Fatalf("reading body: %v", err)
		}
		if len(b) != 10000 {
			t.Fatalf("body length = %d, want %d", len(b), 10000)
		}
	})
}