package oauth

import (
	"fmt"
	"strings"
	"testing"
)

// mockCommandExecutor is a test mock that records executed commands without actually running them.
type mockCommandExecutor struct {
	executedCmd  string
	executedArgs []string
	returnError  error
}

func (m *mockCommandExecutor) Execute(name string, args ...string) error {
	m.executedCmd = name
	m.executedArgs = args
	return m.returnError
}

func TestBuildBrowserCommand(t *testing.T) {
	tests := []struct {
		name        string
		goos        string
		url         string
		wantCmd     string
		wantArgs    []string
		wantErr     bool
		errContains string
	}{
		{
			name:     "macOS with simple URL",
			goos:     "darwin",
			url:      "https://example.com",
			wantCmd:  "open",
			wantArgs: []string{"https://example.com"},
			wantErr:  false,
		},
		{
			name:     "Linux with simple URL",
			goos:     "linux",
			url:      "https://example.com",
			wantCmd:  "xdg-open",
			wantArgs: []string{"https://example.com"},
			wantErr:  false,
		},
		{
			name:     "Windows with simple URL",
			goos:     "windows",
			url:      "https://example.com",
			wantCmd:  "rundll32",
			wantArgs: []string{"url.dll,FileProtocolHandler", "https://example.com"},
			wantErr:  false,
		},
		{
			name:     "macOS with URL containing query params",
			goos:     "darwin",
			url:      "https://example.com/callback?code=123&state=abc",
			wantCmd:  "open",
			wantArgs: []string{"https://example.com/callback?code=123&state=abc"},
			wantErr:  false,
		},
		{
			name:     "Linux with URL containing fragment",
			goos:     "linux",
			url:      "https://example.com/page#section",
			wantCmd:  "xdg-open",
			wantArgs: []string{"https://example.com/page#section"},
			wantErr:  false,
		},
		{
			name:     "Windows with URL containing special chars",
			goos:     "windows",
			url:      "https://example.com/path?key=value&other=123",
			wantCmd:  "rundll32",
			wantArgs: []string{"url.dll,FileProtocolHandler", "https://example.com/path?key=value&other=123"},
			wantErr:  false,
		},
		{
			name:        "unsupported OS",
			goos:        "freebsd",
			url:         "https://example.com",
			wantCmd:     "",
			wantArgs:    nil,
			wantErr:     true,
			errContains: "unsupported platform",
		},
		{
			name:        "unknown OS",
			goos:        "amiga",
			url:         "https://example.com",
			wantCmd:     "",
			wantArgs:    nil,
			wantErr:     true,
			errContains: "amiga",
		},
		{
			name:     "empty URL on macOS",
			goos:     "darwin",
			url:      "",
			wantCmd:  "open",
			wantArgs: []string{""},
			wantErr:  false,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			cmd, args, err := buildBrowserCommand(tt.goos, tt.url)

			// Check error
			if tt.wantErr {
				if err == nil {
					t.Errorf("buildBrowserCommand() expected error, got nil")
					return
				}
				if tt.errContains != "" && !strings.Contains(err.Error(), tt.errContains) {
					t.Errorf("buildBrowserCommand() error = %v, should contain %q", err, tt.errContains)
				}
				return
			}

			if err != nil {
				t.Errorf("buildBrowserCommand() unexpected error = %v", err)
				return
			}

			// Check command
			if cmd != tt.wantCmd {
				t.Errorf("buildBrowserCommand() cmd = %v, want %v", cmd, tt.wantCmd)
			}

			// Check args
			if len(args) != len(tt.wantArgs) {
				t.Errorf("buildBrowserCommand() args length = %d, want %d", len(args), len(tt.wantArgs))
				return
			}
			for i, arg := range args {
				if arg != tt.wantArgs[i] {
					t.Errorf("buildBrowserCommand() args[%d] = %v, want %v", i, arg, tt.wantArgs[i])
				}
			}
		})
	}
}

func TestOpenBrowserWithExecutor(t *testing.T) {
	tests := []struct {
		name          string
		goos          string
		url           string
		executorError error
		wantCmd       string
		wantArgs      []string
		wantErr       bool
		errContains   string
	}{
		{
			name:     "macOS success",
			goos:     "darwin",
			url:      "https://example.com",
			wantCmd:  "open",
			wantArgs: []string{"https://example.com"},
			wantErr:  false,
		},
		{
			name:     "Linux success",
			goos:     "linux",
			url:      "https://example.com/auth",
			wantCmd:  "xdg-open",
			wantArgs: []string{"https://example.com/auth"},
			wantErr:  false,
		},
		{
			name:     "Windows success",
			goos:     "windows",
			url:      "https://example.com/callback?code=123",
			wantCmd:  "rundll32",
			wantArgs: []string{"url.dll,FileProtocolHandler", "https://example.com/callback?code=123"},
			wantErr:  false,
		},
		{
			name:        "unsupported OS",
			goos:        "plan9",
			url:         "https://example.com",
			wantErr:     true,
			errContains: "unsupported platform",
		},
		{
			name:          "executor error",
			goos:          "darwin",
			url:           "https://example.com",
			executorError: fmt.Errorf("exec failed"),
			wantCmd:       "open",
			wantArgs:      []string{"https://example.com"},
			wantErr:       true,
			errContains:   "exec failed",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mock := &mockCommandExecutor{returnError: tt.executorError}

			err := openBrowserWithExecutor(tt.goos, tt.url, mock)

			// Check error
			if tt.wantErr {
				if err == nil {
					t.Errorf("openBrowserWithExecutor() expected error, got nil")
					return
				}
				if tt.errContains != "" && !strings.Contains(err.Error(), tt.errContains) {
					t.Errorf("openBrowserWithExecutor() error = %v, should contain %q", err, tt.errContains)
				}
				return
			}

			if err != nil {
				t.Errorf("openBrowserWithExecutor() unexpected error = %v", err)
				return
			}

			// Verify mock was called with correct command
			if mock.executedCmd != tt.wantCmd {
				t.Errorf("executed command = %v, want %v", mock.executedCmd, tt.wantCmd)
			}

			// Verify mock was called with correct args
			if len(mock.executedArgs) != len(tt.wantArgs) {
				t.Errorf("executed args length = %d, want %d", len(mock.executedArgs), len(tt.wantArgs))
				return
			}
			for i, arg := range mock.executedArgs {
				if arg != tt.wantArgs[i] {
					t.Errorf("executed args[%d] = %v, want %v", i, arg, tt.wantArgs[i])
				}
			}
		})
	}
}