package cli

import (
	"strings"
	"testing"

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

func TestBarStaysWithinItsWidth(t *testing.T) {
	// It is drawn from counts that can disagree briefly — a GPU freed between
	// two reads — and a bar that overruns its column wrecks the table it is in.
	for _, tc := range [][2]int{{0, 0}, {0, 8}, {8, 8}, {9, 8}, {100, 8}} {
		got := bar(tc[0], tc[1])
		if tc[1] == 0 {
			if got != "" {
				t.Errorf("bar(%d,%d) = %q, want empty for an empty class", tc[0], tc[1], got)
			}
			continue
		}
		if n := strings.Count(got, "#") + strings.Count(got, "."); n != 20 {
			t.Errorf("bar(%d,%d) drew %d cells: %q", tc[0], tc[1], n, got)
		}
	}
}

func TestIdleColumnDistinguishesUnknownFromIdle(t *testing.T) {
	// Every replica looks unreported before its first request and after a
	// router restart. Showing that as a very large duration would make an
	// untouched fleet read as an abandoned one.
	if got := idleColumn(-1); got != "-" {
		t.Errorf("idleColumn(-1) = %q, want a dash", got)
	}
	if got := idleColumn(90); got != "1m30s" {
		t.Errorf("idleColumn(90) = %q", got)
	}
}

func TestModelStatusSeparatesWaitingFromBroken(t *testing.T) {
	// These used to differ by a parenthetical — "0/1 ready (1 total)" against
	// "0/1 ready" — and they need opposite responses: one means wait, the other
	// means look at explain-placement. On forty models that difference is
	// invisible.
	for _, tc := range []struct {
		name string
		view adminapi.ModelView
		want string
	}{
		{"serving what it asked for", adminapi.ModelView{Min: 2, Ready: 2, Total: 2}, "ready"},
		{"a replica is coming up", adminapi.ModelView{Min: 1, Ready: 0, Total: 1}, "starting"},
		{"nothing could be placed", adminapi.ModelView{Min: 1, Ready: 0, Total: 0}, "not placed"},
		{"deliberately not running", adminapi.ModelView{Min: 0, Ready: 0, Total: 0}, "stopped"},
		{"short but rebuilding", adminapi.ModelView{Min: 2, Ready: 1, Total: 2}, "starting"},
		{"woken by a request", adminapi.ModelView{Min: 0, Ready: 1, Total: 1}, "ready (on demand)"},
		{"waking", adminapi.ModelView{Min: 0, Ready: 0, Total: 1}, "starting"},
	} {
		t.Run(tc.name, func(t *testing.T) {
			if got := modelStatus(tc.view); got != tc.want {
				t.Errorf("modelStatus(%+v) = %q, want %q", tc.view, got, tc.want)
			}
		})
	}
}

func TestHardwarePoolsNeverMergeAcrossFabrics(t *testing.T) {
	// A replica may never span two fabrics, so eight free cards split across
	// two of them are not eight cards for a model that needs eight. Merging
	// them would plan something that starts, passes health checks and hangs on
	// its first all-reduce.
	nodes := []adminapi.NodeView{
		{ID: "a", State: "ready", Classes: []string{"h100-80g"}, Fabrics: []string{"ib-a"}, GPUFree: 4, GPUTotal: 4},
		{ID: "b", State: "ready", Classes: []string{"h100-80g"}, Fabrics: []string{"ib-a"}, GPUFree: 4, GPUTotal: 4},
		{ID: "c", State: "ready", Classes: []string{"h100-80g"}, Fabrics: []string{"ib-b"}, GPUFree: 4, GPUTotal: 4},
	}
	hw := hardwareFrom(nodes)
	if len(hw) != 2 {
		t.Fatalf("expected one pool per fabric, got %d: %+v", len(hw), hw)
	}
	for _, p := range hw {
		switch p.Fabric {
		case "ib-a":
			if p.Nodes != 2 {
				t.Errorf("ib-a has %d nodes, want 2", p.Nodes)
			}
		case "ib-b":
			if p.Nodes != 1 {
				t.Errorf("ib-b has %d nodes, want 1", p.Nodes)
			}
		default:
			t.Errorf("unexpected fabric %q", p.Fabric)
		}
	}
}

func TestUnreadyNodesAreNotCountedAsCapacity(t *testing.T) {
	// Planning against a node that is draining or unreachable produces a fit
	// that cannot be placed, which is worse than saying nothing fits.
	nodes := []adminapi.NodeView{
		{ID: "a", State: "ready", Classes: []string{"h100-80g"}, GPUFree: 8, GPUTotal: 8},
		{ID: "b", State: "draining", Classes: []string{"h100-80g"}, GPUFree: 8, GPUTotal: 8},
		{ID: "c", State: "unreachable", Classes: []string{"h100-80g"}, GPUFree: 8, GPUTotal: 8},
	}
	hw := hardwareFrom(nodes)
	if len(hw) != 1 || hw[0].Nodes != 1 {
		t.Fatalf("expected only the ready node, got %+v", hw)
	}
}

func TestCardMemoryComesFromTheClassLabel(t *testing.T) {
	// The label carries it by construction — "h100-80g" is eighty gigabytes and
	// says so — which is why the planner needs no table of card models.
	for label, want := range map[string]int{
		"h100-80g": 80, "a100-40g": 40, "l40s-48g": 48, "rtx4090-24g": 24,
		"nonsense": 0, "": 0, "h100-": 0,
	} {
		if got := memFromClass(label); got != want {
			t.Errorf("memFromClass(%q) = %d, want %d", label, got, want)
		}
	}
}

func TestACPUOnlyNodeBecomesAMemoryPool(t *testing.T) {
	// How this cluster began: a node with no cards is not an empty pool, it is
	// a pool measured in RAM.
	hw := hardwareFrom([]adminapi.NodeView{
		{ID: "cpu1", State: "ready", MemoryGB: 31},
	})
	if len(hw) != 1 {
		t.Fatalf("the CPU node produced %d pools", len(hw))
	}
	if hw[0].Class != "" || hw[0].HostMemGB != 31 {
		t.Errorf("pool = %+v, want a classless pool with 31 GB", hw[0])
	}
}

func TestAGPUNodeWithNoFreeCardsIsNotAPool(t *testing.T) {
	// Fully allocated hardware is not capacity, and offering it would plan a
	// replica that cannot be placed.
	hw := hardwareFrom([]adminapi.NodeView{
		{ID: "full", State: "ready", Classes: []string{"h100-80g"}, GPUFree: 0, GPUTotal: 8},
	})
	for _, p := range hw {
		if p.Class != "" {
			t.Errorf("a node with no free cards became a pool: %+v", p)
		}
	}
}

func TestTheEntryNamesAnEngineThatCanServeThePrecision(t *testing.T) {
	// The defect this prevents, found by reading the tool's own output: it
	// chose q8_0 — a GGUF quantisation — and emitted a vLLM profile with no
	// quantisation at all. Following that loads full-precision weights, which
	// the same plan had just shown do not fit on one card. The tool would have
	// caused the out-of-memory it exists to prevent.
	m := modelplan.Model{Name: "Qwen2.5-Coder-32B", Params: 32_800_000_000, Layers: 64, KVHeads: 8, HeadDim: 128}

	gguf := modelplan.Fit{Precision: modelplan.Q8GGUF, Class: "h100-80g", TP: 1, Nodes: 1}
	entry := catalogEntry(m, gguf, "Qwen/Qwen2.5-Coder-32B-Instruct", 32768)
	if !strings.Contains(entry, "engine: llamacpp") {
		t.Errorf("a GGUF precision produced a non-llamacpp profile:\n%s", entry)
	}
	if strings.Contains(entry, "source: Qwen/") {
		t.Errorf("a GGUF entry points at a repository rather than a file:\n%s", entry)
	}
	if !strings.Contains(entry, ".gguf") {
		t.Errorf("a GGUF entry has no file path:\n%s", entry)
	}

	fp8 := modelplan.Fit{Precision: modelplan.FP8, Class: "h100-80g", TP: 2, Nodes: 1}
	entry = catalogEntry(m, fp8, "Qwen/Qwen2.5-Coder-32B-Instruct", 32768)
	if !strings.Contains(entry, "engine: vllm") {
		t.Errorf("fp8 did not produce a vLLM profile:\n%s", entry)
	}
	// And the quantisation has to reach the engine, or vLLM loads bf16.
	if !strings.Contains(entry, "--quantization") || !strings.Contains(entry, "fp8") {
		t.Errorf("the fp8 quantisation is not passed to the engine:\n%s", entry)
	}
	if !strings.Contains(entry, "source: Qwen/") {
		t.Errorf("a vLLM entry should load from the repository:\n%s", entry)
	}
}