/*
Copyright The Helm Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package cli

import (
	"os"
	"reflect"
	"strings"
	"testing"

	"github.com/spf13/pflag"

	"helm.sh/helm/v4/internal/version"
)

func TestSetNamespace(t *testing.T) {
	settings := New()

	if settings.namespace != "" {
		t.Errorf("Expected empty namespace, got %s", settings.namespace)
	}

	settings.SetNamespace("testns")
	if settings.namespace != "testns" {
		t.Errorf("Expected namespace testns, got %s", settings.namespace)
	}
}

func TestEnvSettings(t *testing.T) {
	tests := []struct {
		name string

		// input
		args    string
		envvars map[string]string

		// expected values
		ns, kcontext  string
		debug         bool
		maxhistory    int
		kubeAsUser    string
		kubeAsGroups  []string
		kubeCaFile    string
		kubeInsecure  bool
		kubeTLSServer string
		burstLimit    int
		qps           float32
	}{
		{
			name:       "defaults",
			ns:         "default",
			maxhistory: defaultMaxHistory,
			burstLimit: defaultBurstLimit,
			qps:        defaultQPS,
		},
		{
			name:          "with flags set",
			args:          "--debug --namespace=myns --kube-as-user=poro --kube-as-group=admins --kube-as-group=teatime --kube-as-group=snackeaters --kube-ca-file=/tmp/ca.crt --burst-limit 100  --qps 50.12 --kube-insecure-skip-tls-verify=true --kube-tls-server-name=example.org",
			ns:            "myns",
			debug:         true,
			maxhistory:    defaultMaxHistory,
			burstLimit:    100,
			qps:           50.12,
			kubeAsUser:    "poro",
			kubeAsGroups:  []string{"admins", "teatime", "snackeaters"},
			kubeCaFile:    "/tmp/ca.crt",
			kubeTLSServer: "example.org",
			kubeInsecure:  true,
		},
		{
			name:          "with envvars set",
			envvars:       map[string]string{"HELM_DEBUG": "1", "HELM_NAMESPACE": "yourns", "HELM_KUBEASUSER": "pikachu", "HELM_KUBEASGROUPS": ",,,operators,snackeaters,partyanimals", "HELM_MAX_HISTORY": "5", "HELM_KUBECAFILE": "/tmp/ca.crt", "HELM_BURST_LIMIT": "150", "HELM_KUBEINSECURE_SKIP_TLS_VERIFY": "true", "HELM_KUBETLS_SERVER_NAME": "example.org", "HELM_QPS": "60.34"},
			ns:            "yourns",
			maxhistory:    5,
			burstLimit:    150,
			qps:           60.34,
			debug:         true,
			kubeAsUser:    "pikachu",
			kubeAsGroups:  []string{"operators", "snackeaters", "partyanimals"},
			kubeCaFile:    "/tmp/ca.crt",
			kubeTLSServer: "example.org",
			kubeInsecure:  true,
		},
		{
			name:          "with flags and envvars set",
			args:          "--debug --namespace=myns --kube-as-user=poro --kube-as-group=admins --kube-as-group=teatime --kube-as-group=snackeaters --kube-ca-file=/my/ca.crt --burst-limit 175 --qps 70 --kube-insecure-skip-tls-verify=true --kube-tls-server-name=example.org",
			envvars:       map[string]string{"HELM_DEBUG": "1", "HELM_NAMESPACE": "yourns", "HELM_KUBEASUSER": "pikachu", "HELM_KUBEASGROUPS": ",,,operators,snackeaters,partyanimals", "HELM_MAX_HISTORY": "5", "HELM_KUBECAFILE": "/tmp/ca.crt", "HELM_BURST_LIMIT": "200", "HELM_KUBEINSECURE_SKIP_TLS_VERIFY": "true", "HELM_KUBETLS_SERVER_NAME": "example.org", "HELM_QPS": "40"},
			ns:            "myns",
			debug:         true,
			maxhistory:    5,
			burstLimit:    175,
			qps:           70,
			kubeAsUser:    "poro",
			kubeAsGroups:  []string{"admins", "teatime", "snackeaters"},
			kubeCaFile:    "/my/ca.crt",
			kubeTLSServer: "example.org",
			kubeInsecure:  true,
		},
		{
			name:       "invalid kubeconfig",
			ns:         "testns",
			args:       "--namespace=testns --kubeconfig=/path/to/fake/file",
			maxhistory: defaultMaxHistory,
			burstLimit: defaultBurstLimit,
			qps:        defaultQPS,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			defer resetEnv()()

			for k, v := range tt.envvars {
				t.Setenv(k, v)
			}

			flags := pflag.NewFlagSet("testing", pflag.ContinueOnError)

			settings := New()
			settings.AddFlags(flags)
			flags.Parse(strings.Split(tt.args, " "))

			if settings.Debug != tt.debug {
				t.Errorf("expected debug %t, got %t", tt.debug, settings.Debug)
			}
			if settings.Namespace() != tt.ns {
				t.Errorf("expected namespace %q, got %q", tt.ns, settings.Namespace())
			}
			if settings.KubeContext != tt.kcontext {
				t.Errorf("expected kube-context %q, got %q", tt.kcontext, settings.KubeContext)
			}
			if settings.MaxHistory != tt.maxhistory {
				t.Errorf("expected maxHistory %d, got %d", tt.maxhistory, settings.MaxHistory)
			}
			if tt.kubeAsUser != settings.KubeAsUser {
				t.Errorf("expected kAsUser %q, got %q", tt.kubeAsUser, settings.KubeAsUser)
			}
			if !reflect.DeepEqual(tt.kubeAsGroups, settings.KubeAsGroups) {
				t.Errorf("expected kAsGroups %+v, got %+v", len(tt.kubeAsGroups), len(settings.KubeAsGroups))
			}
			if tt.kubeCaFile != settings.KubeCaFile {
				t.Errorf("expected kCaFile %q, got %q", tt.kubeCaFile, settings.KubeCaFile)
			}
			if tt.burstLimit != settings.BurstLimit {
				t.Errorf("expected BurstLimit %d, got %d", tt.burstLimit, settings.BurstLimit)
			}
			if tt.kubeInsecure != settings.KubeInsecureSkipTLSVerify {
				t.Errorf("expected kubeInsecure %t, got %t", tt.kubeInsecure, settings.KubeInsecureSkipTLSVerify)
			}
			if tt.kubeTLSServer != settings.KubeTLSServerName {
				t.Errorf("expected kubeTLSServer %q, got %q", tt.kubeTLSServer, settings.KubeTLSServerName)
			}
		})
	}
}

func TestEnvOrBool(t *testing.T) {
	const envName = "TEST_ENV_OR_BOOL"
	tests := []struct {
		name     string
		env      string
		val      string
		def      bool
		expected bool
	}{
		{
			name:     "unset with default false",
			def:      false,
			expected: false,
		},
		{
			name:     "unset with default true",
			def:      true,
			expected: true,
		},
		{
			name:     "blank env with default false",
			env:      envName,
			def:      false,
			expected: false,
		},
		{
			name:     "blank env with default true",
			env:      envName,
			def:      true,
			expected: true,
		},
		{
			name:     "env true with default false",
			env:      envName,
			val:      "true",
			def:      false,
			expected: true,
		},
		{
			name:     "env false with default true",
			env:      envName,
			val:      "false",
			def:      true,
			expected: false,
		},
		{
			name:     "env fails parsing with default true",
			env:      envName,
			val:      "NOT_A_BOOL",
			def:      true,
			expected: true,
		},
		{
			name:     "env fails parsing with default false",
			env:      envName,
			val:      "NOT_A_BOOL",
			def:      false,
			expected: false,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if tt.env != "" {
				t.Setenv(tt.env, tt.val)
			}
			actual := envBoolOr(tt.env, tt.def)
			if actual != tt.expected {
				t.Errorf("expected result %t, got %t", tt.expected, actual)
			}
		})
	}
}

func TestEnvInt64OrQuantityBytes(t *testing.T) {
	envName := "TEST_ENV_INT64"

	tests := []struct {
		name     string
		env      string
		val      string
		def      int64
		expected int64
	}{
		{
			name:     "empty env name uses default",
			env:      "",
			val:      "999",
			def:      100,
			expected: 100,
		},
		{
			name:     "env set with valid int64",
			env:      envName,
			val:      "12345",
			def:      100,
			expected: 12345,
		},
		{
			name:     "env fails parsing with default",
			env:      envName,
			val:      "NOT_A_NUMBER",
			def:      100,
			expected: 100,
		},
		{
			name:     "env empty string with default",
			env:      envName,
			val:      "",
			def:      200,
			expected: 200,
		},

		// Quantity cases (bytes)
		{
			name:     "quantity Mi",
			env:      envName,
			val:      "512Mi",
			def:      100,
			expected: 512 * 1024 * 1024,
		},
		{
			name:     "quantity Gi",
			env:      envName,
			val:      "2Gi",
			def:      100,
			expected: 2 * 1024 * 1024 * 1024,
		},
		{
			name:     "quantity Ki",
			env:      envName,
			val:      "4096Ki",
			def:      100,
			expected: 4096 * 1024,
		},
		{
			name: "decimal SI 1G (base10)",
			env:  envName,
			val:  "1G",
			def:  100,
			// 1G in decimal SI is 1,000,000,000 bytes
			expected: 1_000_000_000,
		},
		{
			name:     "decimal SI 500M (base10)",
			env:      envName,
			val:      "500M",
			def:      100,
			expected: 500_000_000,
		},
		{
			name:     "lowercase suffix returns default with error message",
			env:      envName,
			val:      "1gi",
			def:      100,
			expected: 100, // Returns default but prints error about uppercase requirement
		},
		{
			name:     "whitespace trimmed",
			env:      envName,
			val:      " 256Mi ",
			def:      100,
			expected: 256 * 1024 * 1024,
		},
		{
			name: "too large to fit in int64 returns default",
			env:  envName,
			// ~9.22e18 is max int64; use larger than that to trigger overflow handling.
			val:      "10000000000Gi", // 10,000,000,000 * 1024^3 bytes ≈ 1.07e22
			def:      1234,
			expected: 1234,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			// Clear previous value to avoid bleed between tests
			t.Setenv(envName, "")
			if tt.env != "" {
				t.Setenv(tt.env, tt.val)
			}
			actual := envInt64OrQuantityBytes(tt.env, tt.def)
			if actual != tt.expected {
				t.Errorf("expected result %d, got %d (env=%q val=%q def=%d)", tt.expected, actual, tt.env, tt.val, tt.def)
			}
		})
	}
}

func TestUserAgentHeaderInK8sRESTClientConfig(t *testing.T) {
	defer resetEnv()()

	settings := New()
	restConfig, err := settings.RESTClientGetter().ToRESTConfig()
	if err != nil {
		t.Fatal(err)
	}

	expectedUserAgent := version.GetUserAgent()
	if restConfig.UserAgent != expectedUserAgent {
		t.Errorf("expected User-Agent header %q in K8s REST client config, got %q", expectedUserAgent, restConfig.UserAgent)
	}
}

func TestQuantityBytesValue(t *testing.T) {
	tests := []struct {
		name        string
		input       string
		expected    int64
		expectError bool
	}{
		{
			name:     "plain int64",
			input:    "12345",
			expected: 12345,
		},
		{
			name:     "quantity Mi",
			input:    "256Mi",
			expected: 256 * 1024 * 1024,
		},
		{
			name:     "quantity Gi",
			input:    "1Gi",
			expected: 1 * 1024 * 1024 * 1024,
		},
		{
			name:     "quantity with whitespace",
			input:    " 512Mi ",
			expected: 512 * 1024 * 1024,
		},
		{
			name:        "invalid value",
			input:       "not-a-number",
			expectError: true,
		},
		{
			name:        "lowercase suffix rejected",
			input:       "1gi",
			expectError: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			var val int64
			qv := NewQuantityBytesValue(&val)

			err := qv.Set(tt.input)

			if tt.expectError {
				if err == nil {
					t.Errorf("expected error but got none")
				}
			} else {
				if err != nil {
					t.Errorf("unexpected error: %v", err)
				}
				if val != tt.expected {
					t.Errorf("expected %d, got %d", tt.expected, val)
				}
			}
		})
	}
}

func resetEnv() func() {
	origEnv := os.Environ()

	// ensure any local envvars do not hose us
	for e := range New().EnvVars() {
		os.Unsetenv(e)
	}

	return func() {
		for _, pair := range origEnv {
			kv := strings.SplitN(pair, "=", 2)
			os.Setenv(kv[0], kv[1])
		}
	}
}