package lighthouse

import (
	"context"
	"encoding/json"
	"net/http"
	"strings"
	"testing"

	"git.golem15.com/golem15/summercms/modules/pact"
)

// recRouter records the groups and routes Mount registers.
type recRouter struct {
	groups []recGroup
	routes []string
}

type recGroup struct {
	raw        bool
	prefix     string
	middleware []string
	routes     []string
}

func (r *recRouter) group(raw bool, prefix string, mw []string, fn func(pact.Router)) {
	inner := &recRouter{}
	fn(inner)
	r.groups = append(r.groups, recGroup{raw: raw, prefix: prefix, middleware: append([]string(nil), mw...), routes: inner.routes})
}

func (r *recRouter) Group(prefix string, mw []string, fn func(pact.Router)) {
	r.group(false, prefix, mw, fn)
}
func (r *recRouter) GroupRaw(prefix string, mw []string, fn func(pact.Router)) {
	r.group(true, prefix, mw, fn)
}
func (r *recRouter) add(m, p string)                                  { r.routes = append(r.routes, m+" "+p) }
func (r *recRouter) Get(p string, _ http.HandlerFunc, _ ...string)    { r.add("GET", p) }
func (r *recRouter) Post(p string, _ http.HandlerFunc, _ ...string)   { r.add("POST", p) }
func (r *recRouter) Put(p string, _ http.HandlerFunc, _ ...string)    { r.add("PUT", p) }
func (r *recRouter) Patch(p string, _ http.HandlerFunc, _ ...string)  { r.add("PATCH", p) }
func (r *recRouter) Delete(p string, _ http.HandlerFunc, _ ...string) { r.add("DELETE", p) }
func (r *recRouter) Where(string, string)                             {}
func (r *recRouter) WhereIn(string, ...string)                        {}

// routeDriver is a driver that declares the given routes.
type routeDriver struct{ routes []Route }

func (d routeDriver) Name() string    { return "acme" }
func (d routeDriver) Routes() []Route { return d.routes }
func (routeDriver) Publish(context.Context, string, string, json.RawMessage) error {
	return nil
}
func (routeDriver) Broadcast(context.Context, []string, string, json.RawMessage) error {
	return nil
}

func okHandler(http.ResponseWriter, *http.Request) {}

// TestMountSurfaces covers D-13 and T-11-19: UserAuth and Public routes
// mount in a group with the surface middleware then the shared middleware,
// ServerToServer routes in a raw group, every method is registered, a
// UserAuth route without a guard is refused before anything is mounted,
// and a nil driver or the null driver mounts nothing.
func TestMountSurfaces(t *testing.T) {
	s := Surfaces{UserAuth: []string{"jwt.auth"}, ServerToServer: []string{"acme.s2s"}, Public: []string{"acme.public"}, Middleware: []string{"throttle:ws-api"}}
	d := routeDriver{routes: []Route{
		{Name: "token", Method: "get", Path: "/api/rt/token", Surface: UserAuth, Handler: okHandler},
		{Name: "subscribe", Method: http.MethodPost, Path: "/api/rt/subscribe", Surface: ServerToServer, Handler: okHandler},
		{Name: "put", Method: http.MethodPut, Path: "/api/rt/p", Surface: Public, Handler: okHandler},
		{Name: "patch", Method: http.MethodPatch, Path: "/api/rt/p", Surface: Public, Handler: okHandler},
		{Name: "delete", Method: http.MethodDelete, Path: "/api/rt/p", Surface: Public, Handler: okHandler},
	}}
	r := &recRouter{}
	if err := Mount(r, d, s); err != nil {
		t.Fatal(err)
	}
	want := []recGroup{
		{false, "/", []string{"jwt.auth", "throttle:ws-api"}, []string{"GET /api/rt/token"}},
		{true, "/", []string{"acme.s2s", "throttle:ws-api"}, []string{"POST /api/rt/subscribe"}},
		{false, "/", []string{"acme.public", "throttle:ws-api"}, []string{"PUT /api/rt/p"}},
		{false, "/", []string{"acme.public", "throttle:ws-api"}, []string{"PATCH /api/rt/p"}},
		{false, "/", []string{"acme.public", "throttle:ws-api"}, []string{"DELETE /api/rt/p"}},
	}
	if len(r.groups) != len(want) {
		t.Fatalf("groups = %+v", r.groups)
	}
	for i, w := range want {
		g := r.groups[i]
		if g.raw != w.raw || g.prefix != w.prefix || strings.Join(g.middleware, ",") != strings.Join(w.middleware, ",") || strings.Join(g.routes, ",") != strings.Join(w.routes, ",") {
			t.Errorf("group %d = %+v, want %+v", i, g, w)
		}
	}
	if len(s.UserAuth) != 1 || s.UserAuth[0] != "jwt.auth" {
		t.Fatal("Mount mutated the caller's surface middleware")
	}

	refusals := []struct {
		name  string
		route Route
		s     Surfaces
		want  string
	}{
		{"user_route_without_guard", Route{Name: "token", Method: "GET", Path: "/t", Surface: UserAuth, Handler: okHandler}, Surfaces{Middleware: []string{"throttle"}}, "Surfaces.UserAuth is empty"},
		{"no_handler", Route{Name: "x", Method: "GET", Path: "/t", Surface: Public}, s, "has no handler"},
		{"relative_path", Route{Name: "x", Method: "GET", Path: "t", Surface: Public, Handler: okHandler}, s, "must be absolute"},
		{"bad_method", Route{Name: "x", Method: "TRACE", Path: "/t", Surface: Public, Handler: okHandler}, s, "unsupported method"},
		{"unknown_surface", Route{Name: "x", Method: "GET", Path: "/t", Surface: Surface(9), Handler: okHandler}, s, "unknown surface Surface(9)"},
	}
	for _, c := range refusals {
		t.Run(c.name, func(t *testing.T) {
			r := &recRouter{}
			// A valid route first: nothing may be mounted when a later one
			// is invalid.
			valid := Route{Name: "ok", Method: "POST", Path: "/ok", Surface: ServerToServer, Handler: okHandler}
			err := Mount(r, routeDriver{routes: []Route{valid, c.route}}, c.s)
			if err == nil || !strings.Contains(err.Error(), c.want) || !strings.Contains(err.Error(), "driver acme route") {
				t.Fatalf("err = %v, want %q", err, c.want)
			}
			if len(r.groups) != 0 {
				t.Fatalf("mounted %d group(s) before refusing", len(r.groups))
			}
		})
	}

	if err := Mount(nil, d, s); err == nil {
		t.Fatal("nil router accepted")
	}
	r = &recRouter{}
	if err := Mount(r, nil, s); err != nil || len(r.groups) != 0 {
		t.Fatalf("nil driver: err %v, groups %d", err, len(r.groups))
	}
	if err := Mount(r, nullDriver{}, Surfaces{}); err != nil || len(r.groups) != 0 {
		t.Fatalf("null driver: err %v, groups %d", err, len(r.groups))
	}
	for surface, name := range map[Surface]string{UserAuth: "UserAuth", ServerToServer: "ServerToServer", Public: "Public", Surface(0): "Surface(0)"} {
		if surface.String() != name {
			t.Errorf("Surface(%d).String() = %q", int(surface), surface.String())
		}
	}
}