tui/picker.go

// Copyright 2023 Google LLC
//
// 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 tui

import (
	"fmt"
	"io"
	"strings"

	"github.com/charmbracelet/bubbles/list"
	"github.com/charmbracelet/bubbles/spinner"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

type itemDelegate struct{}

func (d itemDelegate) Height() int                               { return 1 }
func (d itemDelegate) Spacing() int                              { return 0 }
func (d itemDelegate) Update(msg tea.Msg, m *list.Model) tea.Cmd { return nil }
func (d itemDelegate) Render(w io.Writer, m list.Model, index int, listItem list.Item) {
	i, ok := listItem.(item)
	if !ok {
		return
	}

	str := fmt.Sprintf("%2d. %-50s", index+1, i.label)

	fn := itemStyle.Render
	if index == m.Index() {
		color := selectedItemStyle.background.code()
		fn = func(s string) string {
			defaultItemStyle := lipgloss.NewStyle().Bold(true)
			return selectedItemStyle.Render(color + "> " + defaultItemStyle.Render(s) + clear)
		}
	}

	fmt.Fprint(w, fn(str))
}

type item struct {
	label, value string
}

func (i item) FilterValue() string { return i.value }

type picker struct {
	dynamicPage

	list         list.Model
	target       string
	defaultValue string
}

func newPicker(listLabel, spinnerLabel, key, defaultValue string, preProcessor tea.Cmd) picker {
	p := picker{}

	l := list.New([]list.Item{}, itemDelegate{}, 0, 19)
	l.Title = listLabel
	l.Styles.Title = titleStyle.style
	l.Styles.PaginationStyle = paginationStyle
	l.Styles.HelpStyle = helpStyle
	p.list = l

	p.showProgress = true
	p.defaultValue = defaultValue
	p.preProcessor = preProcessor
	p.key = key
	p.state = "idle"
	if preProcessor != nil {
		p.state = "querying"
	}

	p.spinnerLabel = spinnerLabel

	s := spinner.New()
	s.Spinner = spinnerType
	p.spinner = s

	return p
}

func positionDefault(items []list.Item, defaultValue string) ([]list.Item, int) {
	selectedIndex := 0
	if defaultValue == "" {
		return items, selectedIndex
	}

	defaultIndex := 0
	newItems := []list.Item{}
	defaultItem := item{}
	createItem := item{}
	returnItems := []list.Item{}

	for i, v := range items {
		item := v.(item)
		if item.value == defaultValue || item.label == defaultValue || defaultValue == item.value+"|"+item.label {
			defaultItem = item
			text := defaultItem.label + " (Default Value)"
			defaultItem.label = text
			items[i] = defaultItem
			defaultIndex = i
			continue
		}
		if strings.Contains(item.label, "Create New Project") {
			createItem = item
			continue
		}
		newItems = append(newItems, item)
	}

	if len(items) <= 10 {
		return items, defaultIndex
	}

	createAdded := 0
	if createItem.label != "" {
		createAdded++
		returnItems = append(returnItems, createItem)
	}

	defaultAdded := 0
	if defaultItem.value != "" {
		defaultAdded++

		returnItems = append(returnItems, defaultItem)
	}

	selectedIndex = (createAdded + defaultAdded) - 1
	if selectedIndex < 0 {
		selectedIndex = 0
	}

	returnItems = append(returnItems, newItems...)

	return returnItems, selectedIndex
}

func (p picker) Init() tea.Cmd {
	return tea.Batch(p.spinner.Tick, p.preProcessor)
}

func (p picker) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case []list.Item:
		p.state = "displaying"
		items := []list.Item(msg)

		offset := len(p.list.Items())

		for i, v := range items {
			p.list.InsertItem(i+offset, v)
		}

		tmp, selectedIndex := positionDefault(p.list.Items(), p.defaultValue)
		p.list.SetItems(tmp)

		p.list.Select(selectedIndex)

		return p, p.spinner.Tick
	case errMsg:
		p.state = "idle"
		p.err = msg
		p.target = msg.target
		return p, nil
	case successMsg:
		p.state = "idle"
		newValue := p.value
		if msg.msg == "prependProject" {
			currentProject := p.queue.Get("currentProject").(string)
			newValue = fmt.Sprintf("%s-%s", currentProject, newValue)
		}

		if !msg.unset && !p.omitFromSettings {
			p.queue.stack.AddSetting(p.key, newValue)
		}

		return p.queue.next()
	case tea.KeyMsg:
		if p.list.FilterState() == list.Filtering {
			break
		}
		switch keypress := msg.String(); keypress {
		case "alt+b", "ctrl+b":
			return p.queue.prev()
		case "ctrl+c":
			return p.queue.exitPage()
		case "enter":
			if p.state == "displaying" {
				i, ok := p.list.SelectedItem().(item)
				if ok {
					p.value = string(i.value)
				}
				if !p.omitFromSettings {
					p.queue.stack.AddSetting(p.key, p.value)
				}

				if p.postProcessor != nil {
					if p.state != "querying" {
						p.state = "querying"
						p.err = nil

						var cmd tea.Cmd
						var cmdSpin tea.Cmd
						cmd = p.postProcessor(p.value, p.queue)
						p.spinner, cmdSpin = p.spinner.Update(msg)

						return p, tea.Batch(cmd, cmdSpin)
					}

					return p, nil
				}

				return p.queue.next()
			}
			if p.err != nil && p.target != "" {
				p.queue.clear(p.target)
				return p.queue.goToModel(p.target)
			}
		}

	default:
		var cmdList tea.Cmd
		var cmdSpin tea.Cmd
		p.list, cmdList = p.list.Update(msg)
		p.spinner, cmdSpin = p.spinner.Update(msg)
		return p, tea.Batch(cmdSpin, cmdList)
	}

	// If this isn't here, then keyPress events do not get responded to by
	// the list ¯\(°_o)/¯
	if p.state == "displaying" {
		var cmd tea.Cmd
		p.list, cmd = p.list.Update(msg)
		return p, cmd
	}

	return p, nil
}

func (p picker) View() string {
	if p.preViewFunc != nil {
		p.preViewFunc(p.queue)
	}
	doc := strings.Builder{}
	doc.WriteString(p.queue.header.render())

	if p.showProgress && p.err == nil {
		doc.WriteString(drawProgress(p.queue.calcPercent()))
		doc.WriteString("\n\n")
	}

	if p.err != nil {
		doc.WriteString(errorAlert{p.err.(errMsg)}.Render())
		return docStyle.Render(doc.String())
	}

	if len(p.content) > 0 {
		inst := strings.Builder{}
		for _, v := range p.content {
			content := v.render()

			inst.WriteString(content)
		}
		doc.WriteString(instructionStyle.Width(width).Render(inst.String()))
		doc.WriteString("\n")
		doc.WriteString("\n")
	}

	if p.state != "waiting" && p.state != "idle" && p.state != "querying" {
		selectedItemStyle.Width(hardWidthLimit)
		doc.WriteString(componentStyle.Render(p.list.View()))
	}

	if p.state == "querying" {
		spinnerSB := strings.Builder{}
		spinnerSB.WriteString(textStyle.Render(fmt.Sprintf("%s ", p.spinnerLabel)))
		spinnerSB.WriteString(spinnerStyle.Render(fmt.Sprintf("%s", p.spinner.View())))
		if p.querySlowText != "" {
			spinnerSB.WriteString(textStyle.Render(fmt.Sprintf("\n%s ", p.querySlowText)))
		}

		doc.WriteString(bodyStyle.Render(spinnerSB.String()))
	}

	return docStyle.Render(doc.String())
}