package cli

import (
	"context"
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"gitea.mynodes.xyz/ilker/llmgw/internal/bundle"
	"gitea.mynodes.xyz/ilker/llmgw/internal/config"
)

// handMadeBundle is a bundle as 'bundle create' leaves it: an engine build
// and the starter model, with their checksums in the manifest.
func handMadeBundle(t *testing.T) (dir, digest string) {
	t.Helper()
	dir = t.TempDir()
	m := bundle.Manifest{Format: bundle.Format, MadeBy: "test",
		Models: []bundle.Model{{Name: starterName, Version: starterVersion, Source: starterSource}}}
	for p, body := range map[string]string{
		"engines/llamacpp/b1/llama-b1-bin-ubuntu-x64.tar.gz":                 "an engine",
		"models/" + starterName + "/" + starterVersion + "/qwen-q4_k_m.gguf": "weights",
	} {
		full := filepath.Join(dir, p)
		_ = os.MkdirAll(filepath.Dir(full), 0o755)
		_ = os.WriteFile(full, []byte(body), 0o644)
		sum := sha256.Sum256([]byte(body))
		m.Files = append(m.Files, bundle.File{Path: p, Bytes: int64(len(body)), SHA256: hex.EncodeToString(sum[:])})
	}
	raw, _ := json.Marshal(m)
	_ = os.WriteFile(filepath.Join(dir, bundle.ManifestName), raw, 0o644)
	return dir, bundle.Digest(raw)
}

func TestInitFromABundleLeavesAnOfflineClusterThatTrustsItsEngines(t *testing.T) {
	in, out := newTestInit(t)
	dir, digest := handMadeBundle(t)
	in.bundle, in.hosts, in.mirrorPath = dir, []string{"10.9.8.7"}, t.TempDir()

	in.bundleSHA = ""
	if err := in.checkBundle(); err == nil || !strings.Contains(err.Error(), "--bundle-sha256") {
		t.Errorf("a bundle with no digest: %v", err)
	}
	in.bundleSHA = strings.Repeat("0", 64)
	if err := in.checkBundle(); err == nil {
		t.Error("a bundle not matching its digest was taken")
	}
	in.bundleSHA = digest
	if err := in.run(context.Background()); err != nil {
		t.Fatalf("%v\n%s", err, out)
	}
	if err := in.ensureBundle(context.Background()); err != nil {
		t.Fatalf("%v\n%s", err, out)
	}

	cfg, err := config.Load(in.configPath())
	if err != nil {
		t.Fatal(err)
	}
	if cfg.Offline.Mirror != "http://10.9.8.7:8081" || cfg.ReleasesBase() != "http://10.9.8.7:8081/_llmgw/releases" {
		t.Errorf("server.yaml: offline %+v, releases %s", cfg.Offline, cfg.ReleasesBase())
	}
	got := bundle.NewTrusted(cfg.Offline.ChecksumsFile()).For("llamacpp", "b1")
	if len(got) != 1 {
		t.Errorf("the control plane trusts %v", got)
	}
	if _, err := os.Stat(filepath.Join(in.mirrorPath, starterName, starterVersion, "qwen-q4_k_m.gguf")); err != nil {
		t.Errorf("the starter model is not in the mirror: %v", err)
	}
	if !in.bundleCarries(starterName) || in.bundleCarries(guardModelName) {
		t.Error("what the bundle carries was misread")
	}

	// Again, and nothing changes: not the mirror, not server.yaml.
	before, _ := os.ReadFile(in.configPath())
	if err := in.ensureBundle(context.Background()); err != nil {
		t.Fatal(err)
	}
	if after, _ := os.ReadFile(in.configPath()); string(after) != string(before) {
		t.Error("init from the same bundle changed server.yaml again")
	}
}