package main

import (
	"bytes"
	"context"
	"encoding/base64"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	dynamicfake "k8s.io/client-go/dynamic/fake"
)

func newTestServer(objs ...runtime.Object) *server {
	listKinds := map[schema.GroupVersionResource]string{
		environmentGVR: "EnvironmentList",
		packageGVR:     "PackageList",
		functionGVR:    "FunctionList",
		httpTrigGVR:    "HTTPTriggerList",
		timeTrigGVR:    "TimeTriggerList",
	}
	dyn := dynamicfake.NewSimpleDynamicClientWithCustomListKinds(runtime.NewScheme(), listKinds, objs...)
	return &server{dyn: dyn, ns: "default", routerURL: "http://example.invalid", http: &http.Client{}, saTokenPath: ""}
}

func TestNormalizeMethods(t *testing.T) {
	got := normalizeMethods([]string{"get", " POST ", "get", ""})
	if len(got) != 2 || got[0] != "GET" || got[1] != "POST" {
		t.Fatalf("unexpected methods: %#v", got)
	}

	fallback := normalizeMethods([]string{"", "   "})
	if len(fallback) != 1 || fallback[0] != "GET" {
		t.Fatalf("expected default GET, got %#v", fallback)
	}
}

func TestCreateFunctionValidation(t *testing.T) {
	s := newTestServer()
	req := httptest.NewRequest(http.MethodPost, "/api/functions", strings.NewReader(`{"name":""}`))
	rec := httptest.NewRecorder()

	s.handleCreateFunction(rec, req)

	if rec.Code != http.StatusBadRequest {
		t.Fatalf("expected 400, got %d: %s", rec.Code, rec.Body.String())
	}
}

func TestCreateFunctionSuccessAndGetDetails(t *testing.T) {
	env := &unstructured.Unstructured{Object: map[string]any{
		"apiVersion": "fission.io/v1",
		"kind":       "Environment",
		"metadata": map[string]any{
			"name":      "python",
			"namespace": "default",
		},
	}}
	s := newTestServer(env)

	body := `{"name":"t-fn","environment":"python","code":"def main(ctx):\n    return {\"ok\": True}","entrypoint":"main.main","route":"/t-fn","methods":["get"]}`
	req := httptest.NewRequest(http.MethodPost, "/api/functions", strings.NewReader(body))
	rec := httptest.NewRecorder()
	s.handleCreateFunction(rec, req)
	if rec.Code != http.StatusCreated {
		t.Fatalf("expected 201, got %d: %s", rec.Code, rec.Body.String())
	}

	ctx := context.Background()
	pkg, err := s.dyn.Resource(packageGVR).Namespace("default").Get(ctx, "t-fn-pkg", metav1.GetOptions{})
	if err != nil {
		t.Fatalf("package not created: %v", err)
	}
	literal, _, _ := unstructured.NestedString(pkg.Object, "spec", "deployment", "literal")
	decoded, err := base64.StdEncoding.DecodeString(literal)
	if err != nil {
		t.Fatalf("decode literal: %v", err)
	}
	if !strings.Contains(string(decoded), "def main") {
		t.Fatalf("unexpected package code: %q", string(decoded))
	}

	getReq := httptest.NewRequest(http.MethodGet, "/api/functions/t-fn", nil)
	getRec := httptest.NewRecorder()
	s.handleGetFunction(getRec, getReq, "t-fn")
	if getRec.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", getRec.Code, getRec.Body.String())
	}

	var out map[string]any
	if err := json.Unmarshal(getRec.Body.Bytes(), &out); err != nil {
		t.Fatalf("decode get response: %v", err)
	}
	if out["name"] != "t-fn" {
		t.Fatalf("unexpected name: %#v", out["name"])
	}
	if out["environment"] != "python" {
		t.Fatalf("unexpected environment: %#v", out["environment"])
	}
}

func TestUpdateFunctionCode(t *testing.T) {
	env := &unstructured.Unstructured{Object: map[string]any{
		"apiVersion": "fission.io/v1",
		"kind":       "Environment",
		"metadata":   map[string]any{"name": "python", "namespace": "default"},
	}}
	s := newTestServer(env)

	createReq := httptest.NewRequest(http.MethodPost, "/api/functions", strings.NewReader(`{"name":"upd-fn","environment":"python","code":"old","entrypoint":"main.main"}`))
	createRec := httptest.NewRecorder()
	s.handleCreateFunction(createRec, createReq)
	if createRec.Code != http.StatusCreated {
		t.Fatalf("create failed: %d %s", createRec.Code, createRec.Body.String())
	}

	updReq := httptest.NewRequest(http.MethodPut, "/api/functions/upd-fn/code", bytes.NewBufferString(`{"code":"new-code"}`))
	updRec := httptest.NewRecorder()
	s.handleUpdateFunctionCode(updRec, updReq, "upd-fn")
	if updRec.Code != http.StatusOK {
		t.Fatalf("update failed: %d %s", updRec.Code, updRec.Body.String())
	}

	ctx := context.Background()
	pkg, err := s.dyn.Resource(packageGVR).Namespace("default").Get(ctx, "upd-fn-pkg", metav1.GetOptions{})
	if err != nil {
		t.Fatalf("get package: %v", err)
	}
	literal, _, _ := unstructured.NestedString(pkg.Object, "spec", "deployment", "literal")
	decoded, err := base64.StdEncoding.DecodeString(literal)
	if err != nil {
		t.Fatalf("decode literal: %v", err)
	}
	if string(decoded) != "new-code" {
		t.Fatalf("expected new-code, got %q", string(decoded))
	}
}

func TestInvokeFunctionWithJWTAuth(t *testing.T) {
	// Mock router: /auth/login returns JWT, /inv-fn returns hello
	var gotAuth string
	mockRouter := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path == "/auth/login" && r.Method == http.MethodPost {
			w.Header().Set("Content-Type", "application/json")
			_, _ = w.Write([]byte(`{"accesstoken":"fake-jwt-token-xyz","tokentype":"Bearer"}`))
			return
		}
		gotAuth = r.Header.Get("Authorization")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{"hello":"world"}`))
	}))
	defer mockRouter.Close()

	env := &unstructured.Unstructured{Object: map[string]any{
		"apiVersion": "fission.io/v1",
		"kind":       "Environment",
		"metadata":   map[string]any{"name": "python", "namespace": "default"},
	}}

	listKinds := map[schema.GroupVersionResource]string{
		environmentGVR: "EnvironmentList",
		packageGVR:     "PackageList",
		functionGVR:    "FunctionList",
		httpTrigGVR:    "HTTPTriggerList",
		timeTrigGVR:    "TimeTriggerList",
	}
	dyn := dynamicfake.NewSimpleDynamicClientWithCustomListKinds(runtime.NewScheme(), listKinds, env)
	s := &server{
		dyn:       dyn,
		ns:        "default",
		routerURL: mockRouter.URL,
		http:      mockRouter.Client(),
		authUser:  "admin",
		authPass:  "pass",
	}

	// Create function first
	createBody := `{"name":"inv-fn","environment":"python","code":"print(1)","route":"/inv-fn","methods":["GET"]}`
	createRec := httptest.NewRecorder()
	s.handleCreateFunction(createRec, httptest.NewRequest(http.MethodPost, "/api/functions", strings.NewReader(createBody)))
	if createRec.Code != http.StatusCreated {
		t.Fatalf("create: %d %s", createRec.Code, createRec.Body.String())
	}

	// Invoke
	invokeRec := httptest.NewRecorder()
	s.handleInvokeFunction(invokeRec, httptest.NewRequest(http.MethodPost, "/api/functions/inv-fn/invoke", strings.NewReader(`{}`)), "inv-fn")
	if invokeRec.Code != http.StatusOK {
		t.Fatalf("invoke: %d %s", invokeRec.Code, invokeRec.Body.String())
	}

	// Verify JWT was obtained via login and sent
	if gotAuth != "Bearer fake-jwt-token-xyz" {
		t.Fatalf("expected 'Bearer fake-jwt-token-xyz', got %q", gotAuth)
	}

	var out map[string]any
	if err := json.Unmarshal(invokeRec.Body.Bytes(), &out); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if out["status"] != float64(200) {
		t.Fatalf("expected status 200, got %v", out["status"])
	}
	if !strings.Contains(out["response_raw"].(string), "hello") {
		t.Fatalf("unexpected response: %v", out["response_raw"])
	}
}