package main

import (
	"context"
	"fmt"
	"net/http"
	"net/http/httptest"
	"strings"
	"sync/atomic"
	"testing"
	"time"

	"github.com/coder/websocket"
	"github.com/coder/websocket/wsjson"

	"github.com/edwardtay/injective-booklab/client"
)

// A fake LCD whose best bid quantity and seq change on every request.
func fakeLCD(hits *int32) *httptest.Server {
	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		n := atomic.AddInt32(hits, 1)
		fmt.Fprintf(w, `{"buys_price_level":[{"p":"9","q":"%d"}],"sells_price_level":[{"p":"10","q":"1"}],"seq":"%d"}`, n, n)
	}))
}

func TestStreamFansOutOnePoller(t *testing.T) {
	var hits int32
	up := fakeLCD(&hits)
	defer up.Close()
	h := &hub{c: client.New(up.URL), every: 30 * time.Millisecond, feeds: map[string]*feed{}}
	srv := httptest.NewServer(routes(h))
	defer srv.Close()
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	url := "ws" + strings.TrimPrefix(srv.URL, "http") + "/v1/stream/m1?kind=spot"
	var conns []*websocket.Conn
	for i := 0; i < 3; i++ {
		c, _, err := websocket.Dial(ctx, url, nil)
		if err != nil {
			t.Fatal(err)
		}
		defer c.CloseNow()
		conns = append(conns, c)
	}
	sawDiff := 0
	for _, c := range conns {
		for i := 0; i < 3; i++ {
			var m msg
			if err := wsjson.Read(ctx, c, &m); err != nil {
				t.Fatal(err)
			}
			if m.Type == "diff" && len(m.Changes) == 1 && m.Changes[0].Side == "bid" {
				sawDiff++
				break
			}
		}
	}
	if sawDiff != 3 {
		t.Fatalf("every client should receive bid diffs, got %d", sawDiff)
	}
	h.mu.Lock()
	feeds := len(h.feeds)
	h.mu.Unlock()
	if feeds != 1 {
		t.Errorf("3 clients on one market should share 1 poller, got %d", feeds)
	}
}

func TestBadSimRequest(t *testing.T) {
	h := &hub{c: client.New("http://127.0.0.1:1"), every: time.Second, feeds: map[string]*feed{}}
	srv := httptest.NewServer(routes(h))
	defer srv.Close()
	resp, err := http.Get(srv.URL + "/v1/sim/m1?side=up&qty=x")
	if err != nil {
		t.Fatal(err)
	}
	if resp.StatusCode != http.StatusBadRequest {
		t.Errorf("want 400, got %d", resp.StatusCode)
	}
}