package web

import (
	"net/http"
	"strings"
	"testing"
	"time"

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

// nodeMux mounts the page where it lives, so the path carries the node.
func nodeMux(src Source, h History) http.Handler {
	mux := http.NewServeMux()
	if h == nil {
		mux.HandleFunc("GET /admin/nodes/{id}", NodePage(src, nil, time.Hour, false, "v1", nil))
	} else {
		mux.HandleFunc("GET /admin/nodes/{id}", NodePage(src, h, time.Hour, false, "v1", nil))
	}
	return mux
}

// busySource is fakeSource with a node that has been measured.
type busySource struct{ fakeSource }

func (busySource) Nodes() []adminapi.NodeView {
	n := fakeSource{}.Nodes()[0]
	n.Load = &adminapi.LoadView{CPUPercent: 62, CPUs: 8, Load1: 3.25, Load5: 2, Load15: 1,
		MemUsed: 6 << 30, MemTotal: 8 << 30, MemPercent: 75}
	return []adminapi.NodeView{n}
}

func (busySource) Replicas(string) []adminapi.ReplicaView {
	r := fakeSource{}.Replicas("")
	r[0].Shards[0].CPUCores, r[0].Shards[0].MemoryBytes = 4, 5<<30
	return r
}

func TestANodesPageShowsHowBusyItIsAndWhatIsUsingIt(t *testing.T) {
	h := &fakeHistory{byExpr: map[string][]promq.Series{
		`llmgw_node_cpu_utilization_percent{node="llmgw-node01"} / 100`: {ts("llmgw-node01", 0.2, 0.6)},
	}}
	code, body := get(t, nodeMux(busySource{}, h), "http://x/admin/nodes/llmgw-node01", nil)
	if code != http.StatusOK {
		t.Fatalf("status %d", code)
	}
	for _, want := range []string{
		"62%", "CPU · 8 cores", "RAM in use", "3.25",
		// The engine and its share: four of eight cores is half the machine.
		"<td>served</td>", "4.0 cores", "width: 50%",
		`hx-get="/admin/nodes/llmgw-node01"`,
	} {
		if !strings.Contains(body, want) {
			t.Errorf("missing %q", want)
		}
	}
	// Every chart is about this node, and nothing else.
	for _, q := range h.asked {
		if !strings.Contains(q, `"llmgw-node01"`) && !strings.Contains(q, `served-1`) {
			t.Errorf("a query not scoped to the node: %s", q)
		}
	}
}

func TestAnUnknownNodeIsNotFound(t *testing.T) {
	h := &fakeHistory{}
	code, _ := get(t, nodeMux(busySource{}, h), "http://x/admin/nodes/nope", nil)
	if code != http.StatusNotFound {
		t.Errorf("status %d", code)
	}
	// Nothing was asked of the metrics store for a name nobody knows.
	if len(h.asked) != 0 {
		t.Errorf("queried for an unknown node: %v", h.asked)
	}
}

func TestANodeNotMeasuredLatelySaysSoRatherThanZero(t *testing.T) {
	_, body := get(t, nodeMux(fakeSource{}, nil), "http://x/admin/nodes/llmgw-node01", nil)
	if !strings.Contains(body, "not measured lately") {
		t.Error("an unmeasured node should say so")
	}
	if !strings.Contains(body, "No metrics store is configured") {
		t.Error("without a metrics store the page should say where history comes from")
	}
}