package web

import (
	"context"
	"io"
	"log/slog"
	"net/http"
	"net/url"
	"strings"
	"testing"
	"time"

	"gitea.mynodes.xyz/ilker/llmgw/internal/control/adminapi"
	"gitea.mynodes.xyz/ilker/llmgw/internal/control/inventory"
	"gitea.mynodes.xyz/ilker/llmgw/internal/store"
)

// buildFleet is one GPU node whose vLLM build was chosen, and one CPU node.
type buildFleet struct{ fakeFleet }

func (buildFleet) Nodes() []adminapi.NodeView {
	return []adminapi.NodeView{
		{ID: "gpu07", State: "ready", GPUTotal: 8, GPUFree: 8,
			EngineBuilds: map[string]string{"vllm": "cu129"},
			Provision:    []inventory.EngineInstall{{Engine: "vllm", Version: "0.30.0", Variant: "cu129", State: "installing"}}},
		{ID: "cpu01", State: "ready"},
	}
}

type recordedChoice struct{ node, engine, build, by string }

type fakeEngineAdmin struct{ got []recordedChoice }

func (f *fakeEngineAdmin) SetNodeEngine(_ context.Context, node, engine, build, by string) error {
	f.got = append(f.got, recordedChoice{node, engine, build, by})
	return nil
}

func TestTheVLLMBuildIsChosenOnTheClusterPage(t *testing.T) {
	a := fakeAccounts{user: store.User{ID: "u1", Email: "a@example.com", IsAdmin: true}}
	p := NewAccountPages(a, nil, nil, "v0", slog.New(slog.NewTextHandler(io.Discard, nil)))
	mux := http.NewServeMux()
	mux.HandleFunc("GET /admin", p.AdminPage(Dashboard(buildFleet{}, nil, "v1", time.Second, false, NavExtras{}, nil)))
	fe := &fakeEngineAdmin{}
	p.RegisterNodeEngines(mux, fe)

	body := mirrorGet(t, mux, "/admin").Body.String()
	if !strings.Contains(body, `action="/admin/nodes/gpu07/engines"`) ||
		!strings.Contains(body, `<option value="cu129" selected>CUDA 12.9</option>`) {
		t.Fatalf("no choice of build for the GPU node, with its current one selected: %s", body)
	}
	if strings.Contains(body, `action="/admin/nodes/cpu01/engines"`) {
		t.Error("a node with no GPU was offered a vLLM build")
	}
	if !strings.Contains(body, "0.30.0 CUDA 12.9 installing") {
		t.Error("what is installed is not shown beside the choice")
	}

	// The read-only page on the admin listener has no session, so no form.
	_, ro := get(t, Dashboard(buildFleet{}, nil, "v1", time.Second, true, NavExtras{}, nil), "http://127.0.0.1:9090/", nil)
	if strings.Contains(ro, "/engines\"") {
		t.Error("the admin listener's page offers a change it cannot sign")
	}

	w := mirrorPost(t, mux, "/admin/nodes/gpu07/engines", url.Values{"csrf": {"tok"}, "engine": {"vllm"}, "build": {"none"}})
	if w.Code != http.StatusSeeOther || len(fe.got) != 1 || fe.got[0] != (recordedChoice{"gpu07", "vllm", "none", "a@example.com"}) {
		t.Fatalf("status %d, chose %+v", w.Code, fe.got)
	}
	if loc := w.Header().Get("Location"); !strings.Contains(loc, "notice=") {
		t.Errorf("redirected to %s, saying nothing", loc)
	}
	if w := mirrorPost(t, mux, "/admin/nodes/gpu07/engines", url.Values{"csrf": {"bad"}, "engine": {"vllm"}, "build": {"none"}}); w.Code != http.StatusBadRequest || len(fe.got) != 1 {
		t.Errorf("a forged form was accepted: %d", w.Code)
	}
}