//go:build e2e

package agentnetwork

import (
	"context"
	"encoding/json"
	"os"
	"sort"
	"strconv"
	"strings"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/netbirdio/netbird/e2e/harness"
	sharedllm "github.com/netbirdio/netbird/shared/llm"
	"github.com/netbirdio/netbird/shared/management/http/api"
)

// TestLiveModelDiscovery drives model discovery against the REAL vendor
// endpoints — OpenAI, Anthropic, Bedrock and Vertex — rather than the mock.
//
// The mock upstream proves the filter's mechanics: it advertises ids we chose,
// so a listing narrowing to the ones we authorised is arithmetic we already
// controlled both sides of. What it cannot prove is that the filter survives
// contact with a real catalogue — ids we never enumerated, dated builds whose
// suffix the vendor picks, surfaces that answer a listing request with
// something other than a listing. That is what this covers, and it is the part
// a QA engineer would otherwise have to walk through by hand.
//
// One proxy serves every case. Each provider gets its own group, policy and
// client, because a model-less request matches exactly ONE route
// (matchModelless): with two providers authorised for the same caller, the
// listing would go to whichever won the tiebreak and the other would go
// untested. Group-scoping the caller makes each provider the only candidate
// for its own client.
func TestLiveModelDiscovery(t *testing.T) {
	cases := liveDiscoveryCases()
	if len(cases) == 0 {
		t.Skip("no provider keys set; source ~/.llm-keys to run live model discovery")
	}

	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Minute)
	defer cancel()

	t.Logf("[discovery] live matrix: %s", strings.Join(caseNames(cases), ", "))

	// Provision every provider, group and policy before the proxy starts: the
	// proxy takes a configuration snapshot at connect time and does not
	// reconcile provider changes made afterwards.
	keys := make(map[string]string, len(cases))
	for i := range cases {
		keys[cases[i].name] = provisionLiveDiscovery(t, ctx, &cases[i])
	}

	endpoint, firstIP, firstClient, px := connectClient(t, ctx, "disc-live", keys[cases[0].name])
	clients := map[string]*harness.Client{cases[0].name: firstClient}
	ips := map[string]string{cases[0].name: firstIP}
	for _, tc := range cases[1:] {
		cl := joinClient(t, ctx, px, endpoint, keys[tc.name])
		ip, err := cl.ResolveProxyIP(ctx, endpoint)
		require.NoError(t, err, "resolve endpoint from the %s client", tc.name)
		clients[tc.name] = cl
		ips[tc.name] = ip
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			runLiveDiscoveryCase(t, ctx, tc, clients[tc.name], endpoint, ips[tc.name])
		})
	}
}

// liveDiscoveryCase is one provider's discovery surface and what the proxy
// must make of it.
type liveDiscoveryCase struct {
	name      string
	catalogID string
	upstream  string
	apiKey    string

	// path is the discovery endpoint the client calls. Not every surface uses
	// /v1/models: Bedrock lists inference profiles instead.
	path string
	// headers the vendor requires on a bare GET (Anthropic versions its API
	// through a header, and rejects a request without one).
	headers []string

	// models the provider record enumerates. Empty models a gateway record,
	// which enumerates nothing and claims everything.
	models []string
	// allowlist, when non-empty, is a guardrail narrowing the policy below the
	// provider's own enumeration — the second of the two bounds discovery
	// applies, and the only one a provider record alone cannot demonstrate.
	allowlist []string

	// routed is false for a surface the proxy must refuse outright because no
	// provider of this shape can serve it.
	routed bool
	// filtered is false where the proxy routes the surface but applies no
	// model bound to the response.
	filtered bool

	// permitted is every id allowed to survive filtering, in the form the
	// provider record registers it. A surviving id counts as permitted when it
	// matches one of these outright or after Anthropic date-normalisation.
	permitted []string
	// wantHidden are ids the upstream is known to advertise and the bound must
	// remove. Only set where we enumerate the model ourselves, so the
	// expectation cannot rot when a vendor changes its catalogue.
	wantHidden []string
}

// liveDiscoveryCases builds the matrix from whichever provider credentials are
// present, mirroring availableProviders' env-var gating so a partial key set
// still yields partial coverage.
func liveDiscoveryCases() []liveDiscoveryCase {
	var cases []liveDiscoveryCase

	// OpenAI enumerates TWO real models and the policy permits one. That is
	// the only case here where both bounds are observable at once: the
	// upstream advertises dozens of ids, the provider record cuts them to two,
	// and the guardrail cuts those to one.
	if k := os.Getenv("OPENAI_TOKEN"); k != "" {
		cases = append(cases, liveDiscoveryCase{
			name: "openai", catalogID: "openai_api", upstream: "https://api.openai.com", apiKey: k,
			path:      "/v1/models",
			models:    []string{"gpt-4o-mini", "gpt-4o"},
			allowlist: []string{"gpt-4o-mini"},
			routed:    true, filtered: true,
			permitted:  []string{"gpt-4o-mini"},
			wantHidden: []string{"gpt-4o"},
		})
	}

	// Anthropic is the surface Claude Code actually calls. Its listing returns
	// DATED build ids (claude-haiku-4-5-20251001) while the provider record
	// registers the undated id, so this is the case that proves the filter's
	// date-normalisation against ids the vendor chose rather than ids we wrote.
	if k := os.Getenv("ANTHROPIC_TOKEN"); k != "" {
		cases = append(cases, liveDiscoveryCase{
			name: "anthropic", catalogID: "anthropic_api", upstream: "https://api.anthropic.com", apiKey: k,
			path:    "/v1/models",
			headers: []string{"anthropic-version: 2023-06-01"},
			models:  []string{"claude-haiku-4-5"},
			routed:  true, filtered: true,
			permitted: []string{"claude-haiku-4-5"},
		})
	}

	// Bedrock lists inference profiles, not models: matchModelless routes
	// /inference-profiles to a Bedrock route and refuses /v1/models for one.
	// Filtering is keyed on /v1/models alone, so this response is routed but
	// NOT bounded — asserted below, and worth knowing rather than assuming.
	if k := os.Getenv("AWS_BEARER_TOKEN_BEDROCK"); k != "" {
		region := os.Getenv("AWS_REGION")
		if region == "" {
			region = "eu-central-1"
		}
		model := os.Getenv("AWS_BEDROCK_MODEL")
		if model == "" {
			model = "global.anthropic.claude-sonnet-4-6"
		}
		cases = append(cases, liveDiscoveryCase{
			name: "bedrock", catalogID: "bedrock_api",
			upstream: "https://bedrock-runtime." + region + ".amazonaws.com", apiKey: k,
			path:   "/inference-profiles",
			models: []string{sharedllm.NormalizeAnthropicModel(strings.TrimPrefix(model, "global."))},
			routed: true, filtered: false,
		})
	}

	// Vertex carries the model in the rawPredict path and serves no listing
	// endpoint at all, so the proxy must refuse discovery rather than rewrite
	// it onto an upstream that would 404.
	if sa := os.Getenv("GOOGLE_VERTEX_SA_BASE64"); sa != "" {
		if project := os.Getenv("GOOGLE_VERTEX_PROJECT"); project != "" {
			region := os.Getenv("GOOGLE_VERTEX_REGION")
			if region == "" {
				region = "global"
			}
			host := "aiplatform.googleapis.com"
			if region != "global" {
				host = region + "-aiplatform.googleapis.com"
			}
			cases = append(cases, liveDiscoveryCase{
				name: "vertex", catalogID: "vertex_ai_api", upstream: "https://" + host,
				apiKey: "keyfile::" + sa,
				path:   "/v1/models",
				routed: false,
			})
		}
	}

	return cases
}

// provisionLiveDiscovery creates the group, provider, optional guardrail and
// policy for one case, and returns the setup key a client joins that group
// with. Scoping each provider to its own group is what keeps it the only
// candidate for its own client's model-less request.
func provisionLiveDiscovery(t *testing.T, ctx context.Context, tc *liveDiscoveryCase) string {
	t.Helper()

	grp, err := srv.API().Groups.Create(ctx, api.PostApiGroupsJSONRequestBody{Name: "e2e-disc-live-" + tc.name})
	require.NoError(t, err, "create group for %s", tc.name)
	t.Cleanup(func() { _ = srv.API().Groups.Delete(context.Background(), grp.Id) })

	ephemeral := false
	sk, err := srv.API().SetupKeys.Create(ctx, api.PostApiSetupKeysJSONRequestBody{
		Name:       "e2e-disc-live-" + tc.name,
		Type:       "reusable",
		ExpiresIn:  86400,
		UsageLimit: 0,
		AutoGroups: []string{grp.Id},
		Ephemeral:  &ephemeral,
	})
	require.NoError(t, err, "mint setup key for %s", tc.name)
	require.NotEmpty(t, sk.Key, "setup key plaintext for %s", tc.name)

	req := api.AgentNetworkProviderRequest{
		Name:        "e2e-disc-live-" + tc.name,
		ProviderId:  tc.catalogID,
		UpstreamUrl: tc.upstream,
		ApiKey:      &tc.apiKey,
		Enabled:     ptr(true),
	}
	if len(tc.models) > 0 {
		models := make([]api.AgentNetworkProviderModel, 0, len(tc.models))
		for _, id := range tc.models {
			models = append(models, api.AgentNetworkProviderModel{Id: id, InputPer1k: 0.001, OutputPer1k: 0.002})
		}
		req.Models = &models
	}
	prov, err := srv.CreateProvider(ctx, req)
	require.NoError(t, err, "create provider %s", tc.name)
	t.Cleanup(func() { _ = srv.DeleteProvider(context.Background(), prov.Id) })

	polReq := api.AgentNetworkPolicyRequest{
		Name:                   "e2e-disc-live-" + tc.name,
		Enabled:                ptr(true),
		SourceGroups:           []string{grp.Id},
		DestinationProviderIds: []string{prov.Id},
	}
	if len(tc.allowlist) > 0 {
		var gr api.AgentNetworkGuardrailRequest
		gr.Name = "e2e-disc-live-" + tc.name
		gr.Checks.ModelAllowlist.Enabled = true
		gr.Checks.ModelAllowlist.Models = tc.allowlist
		g, gerr := srv.CreateGuardrail(ctx, gr)
		require.NoError(t, gerr, "create guardrail for %s", tc.name)
		t.Cleanup(func() { _ = srv.DeleteGuardrail(context.Background(), g.Id) })
		polReq.GuardrailIds = &[]string{g.Id}
	}
	pol, err := srv.CreatePolicy(ctx, polReq)
	require.NoError(t, err, "create policy for %s", tc.name)
	t.Cleanup(func() { _ = srv.DeletePolicy(context.Background(), pol.Id) })

	return sk.Key
}

// runLiveDiscoveryCase issues the discovery request and reports everything the
// vendor said before asserting on any of it. The log is the point on the first
// run: a live catalogue is the one input we do not control, so a failure has to
// arrive with the response that caused it rather than just a count.
func runLiveDiscoveryCase(t *testing.T, ctx context.Context, tc liveDiscoveryCase, cl *harness.Client, endpoint, proxyIP string) {
	t.Helper()

	if !tc.routed {
		code, body, err := cl.Get(ctx, endpoint, proxyIP, tc.path, tc.headers)
		require.NoError(t, err, "request must reach the proxy")
		t.Logf("[discovery] %s GET %s -> %d; body: %s", tc.name, tc.path, code, truncate(body, 2000))
		assert.NotEqual(t, 200, code,
			"%s serves no model listing, so the proxy must refuse discovery rather than rewrite it onto an upstream that would 404; body: %s",
			tc.name, truncate(body, 2000))
		return
	}

	code, body := callUntil(t, func() (int, string, error) {
		return cl.Get(ctx, endpoint, proxyIP, tc.path, tc.headers)
	}, 200)
	t.Logf("[discovery] %s GET %s -> %d; body: %s", tc.name, tc.path, code, truncate(body, 4000))
	require.Equal(t, 200, code, "%s discovery must be served; body: %s", tc.name, truncate(body, 2000))

	ids, ok := listingIDs(body)
	if !ok {
		t.Logf("[discovery] %s: response is not a {\"data\":[{\"id\":…}]} listing; nothing to bound", tc.name)
		// A shape the filter cannot parse is forwarded untouched by design. Say
		// so plainly rather than failing: the contract is that the client gets
		// the upstream's own answer, not a corrupted rewrite.
		assert.False(t, tc.filtered,
			"%s was expected to return a filterable listing but did not; body: %s", tc.name, truncate(body, 2000))
		return
	}
	sort.Strings(ids)
	t.Logf("[discovery] %s: %d ids after filtering: %s", tc.name, len(ids), strings.Join(ids, ", "))

	if !tc.filtered {
		// Routed but not bounded. Recorded as an assertion so that the day
		// filtering does extend to this surface, this test is what tells us.
		t.Logf("[discovery] %s: surface is routed but NOT model-bounded (filtering keys on /v1/models only)", tc.name)
		assert.NotEmpty(t, ids, "%s must return the upstream's own listing untouched", tc.name)
		return
	}

	require.NotEmpty(t, ids, "%s filtered the listing down to nothing; the caller would see an empty picker", tc.name)

	permitted := make(map[string]struct{}, len(tc.permitted)*2)
	for _, id := range tc.permitted {
		permitted[id] = struct{}{}
		permitted[sharedllm.NormalizeAnthropicModel(id)] = struct{}{}
	}
	for _, id := range ids {
		_, direct := permitted[id]
		_, normalised := permitted[sharedllm.NormalizeAnthropicModel(id)]
		assert.Truef(t, direct || normalised,
			"%s offered %q, which no policy on this route permits — every entry the picker shows must be a request the guardrail would allow", tc.name, id)
	}
	for _, hidden := range tc.wantHidden {
		assert.NotContainsf(t, ids, hidden,
			"%s offered %q, which the provider enumerates but the policy does not permit", tc.name, hidden)
	}
}

// listingIDs pulls the model ids out of a listing response. ok is false when
// the body is not the {"data":[{"id":…}]} shape the filter recognises.
func listingIDs(body string) ([]string, bool) {
	var doc struct {
		Data []struct {
			ID string `json:"id"`
		} `json:"data"`
	}
	if err := json.Unmarshal([]byte(body), &doc); err != nil {
		return nil, false
	}
	if doc.Data == nil {
		return nil, false
	}
	ids := make([]string, 0, len(doc.Data))
	for _, entry := range doc.Data {
		ids = append(ids, entry.ID)
	}
	return ids, true
}

func caseNames(cases []liveDiscoveryCase) []string {
	names := make([]string, 0, len(cases))
	for _, c := range cases {
		names = append(names, c.name)
	}
	return names
}

// truncate bounds a logged response body. A live catalogue can run to tens of
// kilobytes, and the useful part is the front.
func truncate(s string, limit int) string {
	if len(s) <= limit {
		return s
	}
	return s[:limit] + "… (" + strconv.Itoa(len(s)-limit) + " more bytes)"
}