package haproxy

import (
	"bytes"
	"strings"
	"testing"

	"git.netcell-it.de/projekte/edgeguard-native/internal/models"
)

func renderView(t *testing.T, v View) string {
	t.Helper()
	var buf bytes.Buffer
	if err := tpl.Execute(&buf, v); err != nil {
		t.Fatalf("template execute: %v", err)
	}
	return buf.String()
}

func mkBackend(id int64, name string, hcp *string) models.Backend {
	return models.Backend{
		ID: id, Name: name, Scheme: "http",
		LBAlgorithm: "roundrobin", Active: true,
		HealthCheckPath: hcp,
	}
}

func mkServer(backendID int64, name, addr string, port int) models.BackendServer {
	return models.BackendServer{
		BackendID: backendID, Name: name, Address: addr, Port: port,
		Weight: 100, Active: true,
	}
}

func TestRender_BaselineHasFrontendsAndApiBackend(t *testing.T) {
	out := renderView(t, View{})
	for _, w := range []string{
		"frontend public_http",
		"frontend public_https",
		"frontend internal_stats",
		"backend api_backend",
		"server api1 127.0.0.1:9443 check",
		"bind :443 ssl crt /etc/edgeguard/tls/",
		"path_beg /.well-known/acme-challenge/",
		"http-request redirect scheme https",
	} {
		if !strings.Contains(out, w) {
			t.Errorf("missing %q in baseline output:\n%s", w, out)
		}
	}
}

func TestRender_DomainRoutesEmitUseBackend(t *testing.T) {
	v := View{
		Backends: []BackendView{
			{Backend: mkBackend(1, "app", nil), Servers: []models.BackendServer{
				mkServer(1, "app", "10.0.0.10", 8080),
			}},
			{Backend: mkBackend(2, "api", nil), Servers: []models.BackendServer{
				mkServer(2, "api", "10.0.0.20", 9000),
			}},
		},
		Domains: []DomainView{{
			Domain: models.Domain{ID: 1, Name: "example.com", Active: true},
			Routes: []RouteView{
				{PathPrefix: "/", BackendID: 1},
				{PathPrefix: "/api", BackendID: 2},
			},
		}},
	}
	out := renderView(t, v)
	for _, w := range []string{
		"backend eg_backend_1",
		"server app 10.0.0.10:8080",
		"backend eg_backend_2",
		"server api 10.0.0.20:9000",
		"balance roundrobin",
		"use_backend eg_backend_1 if { hdr(host) -i example.com } { path_beg / }",
		"use_backend eg_backend_2 if { hdr(host) -i example.com } { path_beg /api }",
	} {
		if !strings.Contains(out, w) {
			t.Errorf("missing %q in output:\n%s", w, out)
		}
	}
}

func TestRender_HealthCheckPathAddsCheckInter(t *testing.T) {
	hcp := "/health"
	v := View{
		Backends: []BackendView{
			{Backend: mkBackend(1, "app", &hcp), Servers: []models.BackendServer{
				mkServer(1, "app", "10.0.0.10", 8080),
			}},
		},
	}
	out := renderView(t, v)
	if !strings.Contains(out, "server app 10.0.0.10:8080 check inter 5s") {
		t.Errorf("expected `check inter 5s` for backend with health_check_path:\n%s", out)
	}
	if !strings.Contains(out, "option httpchk") {
		t.Errorf("expected `option httpchk` when health_check_path set:\n%s", out)
	}
}

func TestRender_HTTPSHealthcheckPinsAlpnHTTP1(t *testing.T) {
	// L7TOUT-Bug: ohne `check-alpn http/1.1` handelt der Check h2
	// aus (vom server-Stmt geerbt) und hängt, weil option httpchk
	// HTTP/1.x sendet. Test stellt sicher dass HTTPS+Healthcheck
	// das ALPN für den Check pinnt.
	hcp := "/"
	v := View{
		Backends: []BackendView{
			{
				Backend: models.Backend{ID: 9, Name: "tls-app", Scheme: "https",
					LBAlgorithm: "roundrobin", HealthCheckPath: &hcp, Active: true},
				Servers: []models.BackendServer{
					{BackendID: 9, Name: "tls-1", Address: "10.0.0.30", Port: 8443, Weight: 100, Active: true},
				},
			},
			{
				// Gegenprobe: HTTP-Backend mit Healthcheck darf KEIN
				// check-alpn bekommen (ALPN gibt's nur bei SSL).
				Backend: models.Backend{ID: 10, Name: "plain-app", Scheme: "http",
					LBAlgorithm: "roundrobin", HealthCheckPath: &hcp, Active: true},
				Servers: []models.BackendServer{
					{BackendID: 10, Name: "plain-1", Address: "10.0.0.31", Port: 80, Weight: 100, Active: true},
				},
			},
		},
	}
	out := renderView(t, v)
	idxTLS := strings.Index(out, "backend eg_backend_9")
	idxPlain := strings.Index(out, "backend eg_backend_10")
	if idxTLS < 0 || idxPlain < 0 {
		t.Fatalf("backend sections missing:\n%s", out)
	}
	tlsBlock := out[idxTLS:idxPlain]
	plainBlock := out[idxPlain:]
	if !strings.Contains(tlsBlock, "check-alpn http/1.1") {
		t.Errorf("HTTPS+healthcheck soll check-alpn http/1.1 pinnen:\n%s", tlsBlock)
	}
	if strings.Contains(plainBlock, "check-alpn") {
		t.Errorf("HTTP-Backend darf KEIN check-alpn bekommen:\n%s", plainBlock)
	}
}

func TestRender_WebSocketEmitsTunnelTimeout(t *testing.T) {
	v := View{
		Backends: []BackendView{
			{
				Backend: models.Backend{ID: 7, Name: "vmm", Scheme: "https",
					LBAlgorithm: "source", WebSocket: true, Active: true},
				Servers: []models.BackendServer{
					{BackendID: 7, Name: "vmm-1", Address: "10.0.5.14", Port: 8006, Weight: 100, Active: true},
				},
			},
			{
				Backend: models.Backend{ID: 8, Name: "api", Scheme: "http",
					LBAlgorithm: "roundrobin", WebSocket: false, Active: true},
				Servers: []models.BackendServer{
					{BackendID: 8, Name: "api-1", Address: "10.0.5.20", Port: 8080, Weight: 100, Active: true},
				},
			},
		},
	}
	out := renderView(t, v)
	// vmm soll tunnel-Timeout haben, api nicht.
	idxVmm := strings.Index(out, "backend eg_backend_7")
	idxApi := strings.Index(out, "backend eg_backend_8")
	if idxVmm < 0 || idxApi < 0 {
		t.Fatalf("backend sections missing in output:\n%s", out)
	}
	vmmBlock := out[idxVmm:idxApi]
	apiBlock := out[idxApi:]
	if !strings.Contains(vmmBlock, "timeout tunnel 1h") {
		t.Errorf("vmm-Block sollte `timeout tunnel 1h` enthalten:\n%s", vmmBlock)
	}
	if strings.Contains(apiBlock, "timeout tunnel") {
		t.Errorf("api-Block soll KEIN `timeout tunnel` enthalten:\n%s", apiBlock)
	}
}

func TestRender_MultiServerPool(t *testing.T) {
	v := View{
		Backends: []BackendView{
			{
				Backend: models.Backend{ID: 1, Name: "vmm", Scheme: "http", LBAlgorithm: "leastconn", Active: true},
				Servers: []models.BackendServer{
					{BackendID: 1, Name: "vmm-1", Address: "10.0.0.11", Port: 8080, Weight: 100, Active: true},
					{BackendID: 1, Name: "vmm-2", Address: "10.0.0.12", Port: 8080, Weight: 100, Active: true},
					{BackendID: 1, Name: "vmm-3", Address: "10.0.0.13", Port: 8080, Weight: 50, Backup: true, Active: true},
				},
			},
		},
	}
	out := renderView(t, v)
	for _, w := range []string{
		"backend eg_backend_1",
		"balance leastconn",
		"server vmm-1 10.0.0.11:8080",
		"server vmm-2 10.0.0.12:8080",
		"server vmm-3 10.0.0.13:8080",
		"weight 50",
		" backup",
	} {
		if !strings.Contains(out, w) {
			t.Errorf("missing %q in multi-server output:\n%s", w, out)
		}
	}
}