package cli

import (
	"bytes"
	"context"
	"errors"
	"io"
	"os"
	"strings"
	"testing"
)

func TestInteractiveSetupPrompterPromptSetupCollectsCredential(t *testing.T) {
	input := strings.NewReader(" imap.example.com \n alice \n secret \n")
	output := &bytes.Buffer{}
	prompter := NewInteractiveSetupPrompter(input, output)

	cred, err := prompter.PromptSetup(context.Background())
	if err != nil {
		t.Fatalf("PromptSetup returned error: %v", err)
	}

	if cred.Host != "imap.example.com" || cred.Username != "alice" || cred.Password != "secret" {
		t.Fatalf("unexpected credential: %#v", cred)
	}
	if got := output.String(); got != "IMAP host: Username: Password: " {
		t.Fatalf("unexpected prompts: %q", got)
	}
}

func TestInteractiveSetupPrompterPromptSetupUsesPasswordReader(t *testing.T) {
	output := &bytes.Buffer{}
	passwordReader := &passwordReaderStub{password: "secret"}
	prompter := NewInteractiveSetupPrompterWithPasswordReader(
		strings.NewReader("imap.example.com\nalice\n"),
		output,
		passwordReader,
	)

	cred, err := prompter.PromptSetup(context.Background())
	if err != nil {
		t.Fatalf("PromptSetup returned error: %v", err)
	}

	if cred.Password != "secret" {
		t.Fatalf("expected password from password reader, got %#v", cred)
	}
	if passwordReader.prompt != "Password: " {
		t.Fatalf("unexpected password prompt %q", passwordReader.prompt)
	}
}

func TestInteractiveSetupPrompterPromptSetupRejectsMissingFields(t *testing.T) {
	input := strings.NewReader("imap.example.com\nalice\n   \n")
	prompter := NewInteractiveSetupPrompter(input, &bytes.Buffer{})

	_, err := prompter.PromptSetup(context.Background())
	if err == nil {
		t.Fatal("expected validation error")
	}
	if !strings.Contains(err.Error(), "password is required") {
		t.Fatalf("expected password validation error, got %v", err)
	}
}

func TestTerminalPasswordReaderReadPasswordUsesHiddenInputForTTY(t *testing.T) {
	hiddenCalls := 0
	fallbackCalls := 0
	reader := terminalPasswordReader{
		input:  os.Stdin,
		output: &bytes.Buffer{},
		isTerminal: func(io.Reader) bool {
			return true
		},
		readHiddenPassword: func(file *os.File) ([]byte, error) {
			hiddenCalls++
			if file != os.Stdin {
				t.Fatalf("expected os.Stdin, got %v", file)
			}
			return []byte("secret"), nil
		},
		readFallbackPassword: func(string) (string, error) {
			fallbackCalls++
			return "", nil
		},
	}

	password, err := reader.ReadPassword("Password: ")
	if err != nil {
		t.Fatalf("ReadPassword returned error: %v", err)
	}

	if password != "secret" {
		t.Fatalf("expected hidden password, got %q", password)
	}
	if hiddenCalls != 1 {
		t.Fatalf("expected hidden reader to be called once, got %d", hiddenCalls)
	}
	if fallbackCalls != 0 {
		t.Fatalf("expected fallback reader not to be called, got %d", fallbackCalls)
	}
}

func TestTerminalPasswordReaderReadPasswordFallsBackWhenInputIsNotTTY(t *testing.T) {
	hiddenCalls := 0
	reader := terminalPasswordReader{
		input:  strings.NewReader("ignored\n"),
		output: &bytes.Buffer{},
		isTerminal: func(io.Reader) bool {
			return false
		},
		readHiddenPassword: func(*os.File) ([]byte, error) {
			hiddenCalls++
			return nil, errors.New("should not be called")
		},
		readFallbackPassword: func(prompt string) (string, error) {
			if prompt != "Password: " {
				t.Fatalf("unexpected prompt %q", prompt)
			}
			return "secret", nil
		},
	}

	password, err := reader.ReadPassword("Password: ")
	if err != nil {
		t.Fatalf("ReadPassword returned error: %v", err)
	}

	if password != "secret" {
		t.Fatalf("expected fallback password, got %q", password)
	}
	if hiddenCalls != 0 {
		t.Fatalf("expected hidden reader not to be called, got %d", hiddenCalls)
	}
}

type passwordReaderStub struct {
	password string
	err      error
	prompt   string
}

func (p *passwordReaderStub) ReadPassword(prompt string) (string, error) {
	p.prompt = prompt
	if p.err != nil {
		return "", p.err
	}
	return p.password, nil
}