package survey

import (
	"bytes"
	"fmt"
	"io"
	"os"
	"strings"
	"testing"

	"github.com/stretchr/testify/assert"

	"github.com/AlecAivazis/survey/v2/core"
	"github.com/AlecAivazis/survey/v2/terminal"
)

func init() {
	// disable color output for all prompts to simplify testing
	core.DisableColor = true
}

func TestSelectRender(t *testing.T) {

	prompt := Select{
		Message: "Pick your word:",
		Options: []string{"foo", "bar", "baz", "buz"},
		Default: "baz",
	}

	helpfulPrompt := prompt
	helpfulPrompt.Help = "This is helpful"

	tests := []struct {
		title    string
		prompt   Select
		data     SelectTemplateData
		expected string
	}{
		{
			"Test Select question output",
			prompt,
			SelectTemplateData{SelectedIndex: 2, PageEntries: core.OptionAnswerList(prompt.Options)},
			strings.Join(
				[]string{
					fmt.Sprintf("%s Pick your word:  [Use arrows to move, type to filter]", defaultIcons().Question.Text),
					"  foo",
					"  bar",
					fmt.Sprintf("%s baz", defaultIcons().SelectFocus.Text),
					"  buz\n",
				},
				"\n",
			),
		},
		{
			"Test Select answer output",
			prompt,
			SelectTemplateData{Answer: "buz", ShowAnswer: true, PageEntries: core.OptionAnswerList(prompt.Options)},
			fmt.Sprintf("%s Pick your word: buz\n", defaultIcons().Question.Text),
		},
		{
			"Test Select question output with help hidden",
			helpfulPrompt,
			SelectTemplateData{SelectedIndex: 2, PageEntries: core.OptionAnswerList(prompt.Options)},
			strings.Join(
				[]string{
					fmt.Sprintf("%s Pick your word:  [Use arrows to move, type to filter, %s for more help]", defaultIcons().Question.Text, string(defaultPromptConfig().HelpInput)),
					"  foo",
					"  bar",
					fmt.Sprintf("%s baz", defaultIcons().SelectFocus.Text),
					"  buz\n",
				},
				"\n",
			),
		},
		{
			"Test Select question output with help shown",
			helpfulPrompt,
			SelectTemplateData{SelectedIndex: 2, ShowHelp: true, PageEntries: core.OptionAnswerList(prompt.Options)},
			strings.Join(
				[]string{
					fmt.Sprintf("%s This is helpful", defaultIcons().Help.Text),
					fmt.Sprintf("%s Pick your word:  [Use arrows to move, type to filter]", defaultIcons().Question.Text),
					"  foo",
					"  bar",
					fmt.Sprintf("%s baz", defaultIcons().SelectFocus.Text),
					"  buz\n",
				},
				"\n",
			),
		},
	}

	for _, test := range tests {
		t.Run(test.title, func(t *testing.T) {
			r, w, err := os.Pipe()
			assert.NoError(t, err)

			test.prompt.WithStdio(terminal.Stdio{Out: w})
			test.data.Select = test.prompt

			// set the icon set
			test.data.Config = defaultPromptConfig()

			err = test.prompt.Render(
				SelectQuestionTemplate,
				test.data,
			)
			assert.NoError(t, err)

			assert.NoError(t, w.Close())
			var buf bytes.Buffer
			_, err = io.Copy(&buf, r)
			assert.NoError(t, err)

			assert.Contains(t, buf.String(), test.expected)
		})
	}
}

func TestSelectPrompt(t *testing.T) {
	tests := []PromptTest{
		{
			"basic interaction: blue",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select blue.
				c.SendLine(string(terminal.KeyArrowDown))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 1, Value: "blue"},
		},
		{
			"basic interaction: green",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select blue.
				c.Send(string(terminal.KeyArrowDown))
				// Select green.
				c.SendLine(string(terminal.KeyTab))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"default value",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				Default: "green",
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select green.
				c.SendLine("")
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"default index",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				Default: 2,
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select green.
				c.SendLine("")
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"overriding default",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				Default: "blue",
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select red.
				c.SendLine(string(terminal.KeyArrowUp))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 0, Value: "red"},
		},
		{
			"SKIP: prompt for help",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				Help:    "My favourite color is red",
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				c.SendLine("?")
				c.ExpectString("My favourite color is red")
				// Select red.
				c.SendLine("")
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 0, Value: "red"},
		},
		{
			"PageSize",
			&Select{
				Message:  "Choose a color:",
				Options:  []string{"red", "blue", "green"},
				PageSize: 1,
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select green.
				c.SendLine(string(terminal.KeyArrowUp))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"vim mode",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				VimMode: true,
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Select blue.
				c.SendLine("j")
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 1, Value: "blue"},
		},
		{
			"filter",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Filter down to red and green.
				c.Send("re")
				// Select green.
				c.SendLine(string(terminal.KeyArrowDown))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"filter is case-insensitive",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Filter down to red and green.
				c.Send("RE")
				// Select green.
				c.SendLine(string(terminal.KeyArrowDown))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"Can select the first result in a filtered list if there is a default",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				Default: "blue",
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Make sure only red is showing
				c.SendLine("red")
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 0, Value: "red"},
		},
		{
			"custom filter",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
				Filter: func(filter string, optValue string, optIndex int) (filtered bool) {
					return len(optValue) >= 5
				},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Filter down to only green since custom filter only keeps options that are longer than 5 runes
				c.SendLine("re")
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "green"},
		},
		{
			"answers filtered out",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "green"},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// filter away everything
				c.SendLine("z")
				// send enter (should get ignored since there are no answers)
				c.SendLine(string(terminal.KeyEnter))

				// remove the filter we just applied
				c.SendLine(string(terminal.KeyBackspace))

				// press enter
				c.SendLine(string(terminal.KeyEnter))
			},
			core.OptionAnswer{Index: 0, Value: "red"},
		},
		{
			"delete filter word",
			&Select{
				Message: "Choose a color:",
				Options: []string{"red", "blue", "black"},
			},
			func(c expectConsole) {
				c.ExpectString("Choose a color:")
				// Filter down to blue.
				c.Send("blu")
				// Filter down to blue and black.
				c.Send(string(terminal.KeyDelete))
				// Select black.
				c.SendLine(string(terminal.KeyArrowDown))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "black"},
		},
		{
			"delete filter word in rune",
			&Select{
				Message: "今天中午吃什么？",
				Options: []string{"青椒牛肉丝", "小炒肉", "小煎鸡"},
			},
			func(c expectConsole) {
				c.ExpectString("今天中午吃什么？")
				// Filter down to 小炒肉.
				c.Send("小炒")
				// Filter down to 小炒肉 and 小煎鸡.
				c.Send(string(terminal.KeyBackspace))
				// Select 小煎鸡.
				c.SendLine(string(terminal.KeyArrowDown))
				c.ExpectEOF()
			},
			core.OptionAnswer{Index: 2, Value: "小煎鸡"},
		},
	}

	for _, test := range tests {
		testName := strings.TrimPrefix(test.name, "SKIP: ")
		t.Run(testName, func(t *testing.T) {
			if testName != test.name {
				t.Skipf("warning: flakey test %q", testName)
			}
			RunPromptTest(t, test)
		})
	}
}