// Copyright 2026 Versity Software
// This file is 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 embedgw

import (
	"context"
	"slices"
	"strings"
	"testing"

	"github.com/versity/versitygw/backend"
)

func TestValidatePortConflicts(t *testing.T) {
	tests := []struct {
		name         string
		ports        []string
		admPorts     []string
		webuiPorts   []string
		websitePorts []string
		expectError  bool
		description  string
	}{
		{
			name:        "bare port conflict with bare port",
			ports:       []string{":7071"},
			admPorts:    []string{},
			webuiPorts:  []string{":7071"},
			expectError: true,
			description: "should fail: bare :7071 conflicts with bare :7071",
		},
		{
			name:        "bare port conflict with IP:port",
			ports:       []string{":7071"},
			admPorts:    []string{},
			webuiPorts:  []string{"127.0.0.1:7071"},
			expectError: true,
			description: "should fail: bare :7071 conflicts with 127.0.0.1:7071",
		},
		{
			name:        "IP:port conflict with bare port",
			ports:       []string{"127.0.0.1:7071"},
			admPorts:    []string{},
			webuiPorts:  []string{":7071"},
			expectError: true,
			description: "should fail: 127.0.0.1:7071 conflicts with bare :7071",
		},
		{
			name:        "same IP:port allowed",
			ports:       []string{"127.0.0.1:7071"},
			admPorts:    []string{},
			webuiPorts:  []string{"127.0.0.1:7071"},
			expectError: false,
			description: "should pass: identical IP:port specs are allowed",
		},
		{
			name:        "different IP:port no conflict",
			ports:       []string{"127.0.0.1:7071"},
			admPorts:    []string{},
			webuiPorts:  []string{"127.0.0.1:7072"},
			expectError: false,
			description: "should pass: different ports don't conflict",
		},
		{
			name:        "different IP same port no conflict when both have IP",
			ports:       []string{"127.0.0.1:7071"},
			admPorts:    []string{},
			webuiPorts:  []string{"192.168.1.1:7071"},
			expectError: false,
			description: "should pass: different IPs with same port are okay",
		},
		{
			name:        "admin port conflict with s3 port",
			ports:       []string{":7070"},
			admPorts:    []string{"127.0.0.1:7070"},
			webuiPorts:  []string{},
			expectError: true,
			description: "should fail: admin port conflicts with s3 port",
		},
		{
			name:        "all three conflict",
			ports:       []string{":8080"},
			admPorts:    []string{"127.0.0.1:8080"},
			webuiPorts:  []string{"192.168.1.1:8080"},
			expectError: true,
			description: "should fail: bare port conflicts with both admin and webui",
		},
		{
			name:        "no conflicts",
			ports:       []string{":7070"},
			admPorts:    []string{":8080"},
			webuiPorts:  []string{":9090"},
			expectError: false,
			description: "should pass: all different ports",
		},
		{
			name:        "IPv6 bare port conflict with IPv4 specified",
			ports:       []string{":7071"},
			admPorts:    []string{},
			webuiPorts:  []string{"[::1]:7071"},
			expectError: true,
			description: "should fail: bare :7071 conflicts with [::1]:7071",
		},
		{
			name:        "multiple ports with one conflict",
			ports:       []string{":7070", ":8080"},
			admPorts:    []string{":9090"},
			webuiPorts:  []string{"127.0.0.1:8080"},
			expectError: true,
			description: "should fail: :8080 conflicts with 127.0.0.1:8080",
		},
		{
			name:         "website bare port conflict with s3 port",
			ports:        []string{"127.0.0.1:8080"},
			admPorts:     []string{},
			webuiPorts:   []string{},
			websitePorts: []string{":8080"},
			expectError:  true,
			description:  "should fail: website bare :8080 conflicts with s3 127.0.0.1:8080",
		},
		{
			name:         "website no conflict",
			ports:        []string{":7070"},
			admPorts:     []string{":8080"},
			webuiPorts:   []string{":9090"},
			websitePorts: []string{":8081"},
			expectError:  false,
			description:  "should pass: website uses a distinct port",
		},
		{
			name:         "duplicate website unix socket conflict",
			ports:        []string{"/tmp/versitygw.sock"},
			admPorts:     []string{},
			webuiPorts:   []string{},
			websitePorts: []string{"/tmp/versitygw.sock"},
			expectError:  true,
			description:  "should fail: duplicate unix socket path conflicts across s3 and website",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := validatePortConflicts(tt.ports, tt.admPorts, tt.webuiPorts, tt.websitePorts)
			if tt.expectError && err == nil {
				t.Errorf("%s: expected error but got none", tt.description)
			}
			if !tt.expectError && err != nil {
				t.Errorf("%s: expected no error but got: %v", tt.description, err)
			}
		})
	}
}

func TestValidateAdminPathPrefix(t *testing.T) {
	tests := []struct {
		prefix  string
		wantErr bool
	}{
		{prefix: "", wantErr: false},
		{prefix: "/admin", wantErr: false},
		{prefix: "/vgw-admin_1.0~x", wantErr: false},
		{prefix: "admin", wantErr: true},
		{prefix: "/", wantErr: true},
		{prefix: "/admin/", wantErr: true},
		{prefix: "/api/admin", wantErr: true},
		{prefix: "/.", wantErr: true},
		{prefix: "/..", wantErr: true},
		{prefix: "/ad min", wantErr: true},
		{prefix: "/:bucket", wantErr: true},
		{prefix: "/admin*", wantErr: true},
		{prefix: "/admin%20", wantErr: true},
		{prefix: "/admin?x", wantErr: true},
		{prefix: " /admin", wantErr: true},
	}

	for _, tt := range tests {
		t.Run(tt.prefix, func(t *testing.T) {
			err := validateAdminPathPrefix(tt.prefix)
			if (err != nil) != tt.wantErr {
				t.Fatalf("validateAdminPathPrefix(%q) = %v, wantErr %v", tt.prefix, err, tt.wantErr)
			}
		})
	}
}

func TestAppendPathPrefix(t *testing.T) {
	urls := []string{"http://127.0.0.1:7070", "https://s3.example.com/"}

	got := appendPathPrefix(urls, "/admin")
	want := []string{"http://127.0.0.1:7070/admin", "https://s3.example.com/admin"}
	if !slices.Equal(got, want) {
		t.Fatalf("appendPathPrefix = %v, want %v", got, want)
	}
	if urls[0] != "http://127.0.0.1:7070" {
		t.Fatalf("appendPathPrefix modified its input: %v", urls)
	}
	if got := appendPathPrefix(urls, ""); !slices.Equal(got, urls) {
		t.Fatalf("appendPathPrefix without prefix = %v, want %v", got, urls)
	}
}

func TestRunVersityGWValidatesAdminPathPrefix(t *testing.T) {
	tests := []struct {
		name    string
		mutate  func(*Config)
		wantErr string
	}{
		{
			name: "invalid prefix",
			mutate: func(cfg *Config) {
				cfg.AdminPathPrefix = "/api/admin"
			},
			wantErr: "invalid AdminPathPrefix",
		},
		{
			name: "same as webui s3 prefix",
			mutate: func(cfg *Config) {
				cfg.AdminPathPrefix = "/ui"
				cfg.WebuiS3Prefix = "/UI"
			},
			wantErr: "must differ from WebuiS3Prefix",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			cfg := Config{
				RootUserAccess:    "root",
				RootUserSecret:    "secret",
				Ports:             []string{"127.0.0.1:0"},
				MaxConnections:    1,
				MaxRequests:       1,
				MultipartMaxParts: 1,
				Quiet:             true,
			}
			tt.mutate(&cfg)

			err := RunVersityGW(context.Background(), backend.BackendUnsupported{}, &cfg)
			if err == nil {
				t.Fatal("expected error, got nil")
			}
			if !strings.Contains(err.Error(), tt.wantErr) {
				t.Fatalf("error = %q, want substring %q", err, tt.wantErr)
			}
		})
	}
}