package adminapi

import (
	"testing"
	"time"

	"gitea.mynodes.xyz/ilker/llmgw/internal/agent/discovery"
	"gitea.mynodes.xyz/ilker/llmgw/internal/control/inventory"
)

func TestSummaryCountsCapacityByClass(t *testing.T) {
	// The question a per-node table answers badly at two hundred nodes: how
	// full am I.
	a, _ := setup(t, testModels(), gpuNode("n1", 8), gpuNode("n2", 8))
	s := a.Summary()

	if s.Nodes.Total != 2 || s.Nodes.Ready != 2 {
		t.Errorf("nodes = %+v", s.Nodes)
	}
	if len(s.GPUs) != 1 {
		t.Fatalf("expected one GPU class, got %+v", s.GPUs)
	}
	if g := s.GPUs[0]; g.Total != 16 || g.Free() != 16 {
		t.Errorf("class totals wrong: %+v", g)
	}
}

func TestUnhealthyGPUsAreNotCountedAsFree(t *testing.T) {
	// Counting them free is how a cluster looks like it has room it does not,
	// which is worse than showing less capacity than exists.
	n := gpuNode("n1", 4)
	n.GPUs[0].Health.Problems = []string{"3 uncorrected ECC errors"}
	a, _ := setup(t, testModels(), n)

	g := a.Summary().GPUs[0]
	if g.Unhealthy != 1 {
		t.Errorf("unhealthy = %d", g.Unhealthy)
	}
	if g.Free() != 3 {
		t.Errorf("free = %d; a faulty card was counted as available", g.Free())
	}
}

func TestFabricFreeBlocksCountWholeNodesOnly(t *testing.T) {
	// A multi-node replica may never span fabrics, and a node with one card in
	// use cannot contribute a full-width shard. Free cards scattered across
	// partly-used nodes are not capacity for the model that needs them.
	free := gpuNode("free", 8, "ib-a")
	partial := gpuNode("partial", 8, "ib-a")
	a, ctl := setup(t, testModels(), free, partial)
	// Take one GPU on the second node.
	ctl.Inventory().Allocate("partial", inventory.Allocation{
		ShardID: "s", ReplicaID: "r", GPUIndices: []int{0},
	})

	s := a.Summary()
	if len(s.Fabrics) != 1 {
		t.Fatalf("fabrics = %+v", s.Fabrics)
	}
	if got := s.Fabrics[0].LargestFreeBlock; got != 1 {
		t.Errorf("fully free nodes = %d, want 1: a partly used node is not one", got)
	}
}

func TestANodeWithNoGPUsDoesNotInventAClass(t *testing.T) {
	// The CPU-only node this fleet acquired. It has no class, and a summary
	// that invents one for it would report capacity nobody has.
	a, _ := setup(t, testModels(), inventory.Node{ID: "cpu1", State: inventory.Ready})
	s := a.Summary()
	for _, g := range s.GPUs {
		if g.Class == "" {
			t.Errorf("an empty class was reported: %+v", g)
		}
	}
	if s.Nodes.Total != 1 {
		t.Errorf("the node was not counted: %+v", s.Nodes)
	}
}

func TestIdleReplicasNeedRealIdleness(t *testing.T) {
	// A replica the router has said nothing about carries -1, and must not be
	// read as idle since the epoch — otherwise a router restart nominates the
	// whole fleet for eviction at once.
	for _, tc := range []struct {
		name string
		idle int64
		want bool
	}{
		{"never reported", -1, false},
		{"just used", 5, false},
		{"idle for an hour", int64(time.Hour.Seconds()), true},
	} {
		t.Run(tc.name, func(t *testing.T) {
			got := tc.idle >= int64(idleThreshold.Seconds())
			if got != tc.want {
				t.Errorf("idle=%d counted as idle=%v, want %v", tc.idle, got, tc.want)
			}
		})
	}
}

func TestSummaryNamesModelsThatCannotBePlaced(t *testing.T) {
	// The line that turns "something is wrong" into a place to look.
	a, _ := setup(t, testModels()) // no nodes at all
	s := a.Summary()
	if len(s.Unplaceable) == 0 {
		t.Fatal("a model with no hardware to run on was not named")
	}
	if s.Models.Short == 0 {
		t.Error("no model was counted short")
	}
}

func TestWeightsAreCountedPerFabric(t *testing.T) {
	// Fabrics are not connected, so weights in one are not weights in another.
	// A model seeded into a single fabric leaves the rest of the cluster unable
	// to serve it without first moving tens of gigabytes over the management
	// network, and nothing said so.
	a1 := gpuNode("a1", 4, "ib-a")
	a1.Weights = []discovery.LocalWeights{{Path: "/models/llama.gguf"}}
	a2 := gpuNode("a2", 4, "ib-a")
	a2.Weights = []discovery.LocalWeights{{Path: "/models/llama.gguf"}}
	b1 := gpuNode("b1", 4, "ib-b") // the same fabric capacity, none of the weights

	api, _ := setup(t, testModels(), a1, a2, b1)
	s := api.Summary()

	byName := map[string]FabricUse{}
	for _, f := range s.Fabrics {
		byName[f.Fabric] = f
	}
	if got := byName["ib-a"]; got.Models != 1 || got.NodesWithWeights != 2 {
		t.Errorf("ib-a = %+v, want one model on two nodes", got)
	}
	if got := byName["ib-b"]; got.Models != 0 || got.NodesWithWeights != 0 {
		t.Errorf("ib-b = %+v; it holds nothing and should say so", got)
	}
}

func TestOneSharedCopyCountsAsMuchAsTwenty(t *testing.T) {
	// A filer mounted on every node and a local copy on every node are the same
	// answer to "can this fabric serve it", which is the question being asked.
	var nodes []inventory.Node
	for _, id := range []string{"n1", "n2", "n3"} {
		n := gpuNode(id, 4, "ib-a")
		n.Weights = []discovery.LocalWeights{{Path: "/mnt/shared/llama.gguf", Shared: true}}
		nodes = append(nodes, n)
	}
	api, _ := setup(t, testModels(), nodes...)

	f := api.Summary().Fabrics[0]
	if f.Models != 1 {
		t.Errorf("counted %d models; three nodes seeing one file is one model", f.Models)
	}
}