package main

import "testing"

func TestRenderGatewayConfAuthPerRoute(t *testing.T) {
	cfg := &GatewayConfig{
		ListenPort: 8081,
		AuthURL:    "http://127.0.0.1:4001/_auth",
		LoginURL:   "https://login.example.com/login",
		Routes: []Route{
			{Host: "protected.example.com", Upstream: "http://10.0.0.1:3000", RequireLogin: true, Websocket: true, MaxBodyMB: 64},
			{Host: "open.example.com", Upstream: "http://10.0.0.2:8000"},
		},
	}
	out, err := RenderGatewayConf(cfg)
	if err != nil {
		t.Fatalf("渲染失败: %v", err)
	}
	// 受保护的域名要有 auth_request 与登录跳转
	if !contains(out, "server_name protected.example.com;") {
		t.Fatalf("缺少受保护域名的 server 块:\n%s", out)
	}
	if !contains(out, "auth_request /_auth;") {
		t.Fatalf("受保护域名缺少 auth_request:\n%s", out)
	}
	if !contains(out, "location @login") {
		t.Fatalf("缺少登录跳转")
	}
	if !contains(out, "proxy_set_header Upgrade $http_upgrade;") {
		t.Fatalf("缺少 websocket 透传")
	}
	if !contains(out, "client_max_body_size 64m;") {
		t.Fatalf("缺少上传上限")
	}
	// 不受保护的域名不得出现 auth_request（"哪些服务受保护"是按路由决定的）
	open := section(out, "server_name open.example.com;")
	if open == "" {
		t.Fatalf("缺少开放域名的 server 块")
	}
	if contains(open, "auth_request") {
		t.Fatalf("未受保护的域名不应有 auth_request:\n%s", open)
	}
	if contains(open, "client_max_body_size") {
		t.Fatalf("未设置上限时不应生成 client_max_body_size:\n%s", open)
	}
}

func TestRenderGatewayConfRejectsBadInput(t *testing.T) {
	base := func(r Route) *GatewayConfig {
		return &GatewayConfig{ListenPort: 8081, AuthURL: "http://x/_auth", Routes: []Route{r}}
	}
	cases := []struct {
		name string
		cfg  *GatewayConfig
	}{
		{"空域名", base(Route{Host: "", Upstream: "http://a"})},
		{"域名带协议", base(Route{Host: "http://a.com", Upstream: "http://a"})},
		{"后端非 http", base(Route{Host: "a.com", Upstream: "10.0.0.1:80"})},
		{"域名重复", &GatewayConfig{ListenPort: 8081, AuthURL: "http://x/_auth", Routes: []Route{
			{Host: "a.com", Upstream: "http://a"}, {Host: "a.com", Upstream: "http://b"},
		}}},
		{"需认证但无认证地址", &GatewayConfig{ListenPort: 8081, Routes: []Route{{Host: "a.com", Upstream: "http://a", RequireLogin: true}}}},
		{"启用HTTPS但无证书", &GatewayConfig{ListenPort: 8081, ListenHTTPS: true, Routes: []Route{{Host: "a.com", Upstream: "http://a"}}}},
	}
	for _, c := range cases {
		if _, err := RenderGatewayConf(c.cfg); err == nil {
			t.Errorf("%s: 应当报错但没有", c.name)
		}
	}
}

func TestGatewayRoundTrip(t *testing.T) {
	dir := t.TempDir()
	oldFile, oldOut := gatewayFile, gatewayOutDir
	gatewayFile = dir + "/gateway.yml"
	gatewayOutDir = dir + "/gateway"
	defer func() { gatewayFile, gatewayOutDir = oldFile, oldOut }()

	// 文件不存在时应给出默认配置而不是报错
	cfg, err := loadGateway()
	if err != nil {
		t.Fatalf("缺文件应回落默认配置: %v", err)
	}
	if cfg.ListenPort != 8081 || len(cfg.Routes) != 0 {
		t.Fatalf("默认配置不对: %+v", cfg)
	}
	cfg.Routes = []Route{{Host: "a.com", Upstream: "http://a", RequireLogin: true}}
	if err := saveGateway(cfg); err != nil {
		t.Fatalf("保存失败: %v", err)
	}
	got, err := loadGateway()
	if err != nil || len(got.Routes) != 1 || !got.Routes[0].RequireLogin {
		t.Fatalf("回读不一致: %+v err=%v", got, err)
	}
}

func contains(hay, needle string) bool {
	return len(hay) >= len(needle) && (func() bool {
		for i := 0; i+len(needle) <= len(hay); i++ {
			if hay[i:i+len(needle)] == needle {
				return true
			}
		}
		return false
	})()
}

// section 取出 server_name 所属的那个 server 块（到下一个 server{ 之前）
func section(all, marker string) string {
	i := indexOf(all, marker)
	if i < 0 {
		return ""
	}
	start := i
	for start > 0 && all[start-1] != '\n' {
		start--
	}
	rest := all[i:]
	if j := indexOf(rest, "\nserver {"); j >= 0 {
		return rest[:j]
	}
	return rest
}

func indexOf(hay, needle string) int {
	for i := 0; i+len(needle) <= len(hay); i++ {
		if hay[i:i+len(needle)] == needle {
			return i
		}
	}
	return -1
}