From cdfe068cd23a58be1a947e208232931bc13550d9 Mon Sep 17 00:00:00 2001
From: decentral1se <cellarspoon@riseup.net>
Date: Wed, 10 May 2023 19:24:10 +0200
Subject: [PATCH] feat: datasheet loading spinner

---
 gshmm.go | 98 +++++++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 69 insertions(+), 29 deletions(-)

diff --git a/gshmm.go b/gshmm.go
index 534215a..d49443d 100644
--- a/gshmm.go
+++ b/gshmm.go
@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/charmbracelet/bubbles/spinner"
 	"github.com/charmbracelet/bubbles/textinput"
 	"github.com/charmbracelet/bubbles/viewport"
 	tea "github.com/charmbracelet/bubbletea"
@@ -68,9 +69,11 @@ func readPDF(name string) (string, error) {
 type model struct {
 	input textinput.Model // Fuzzy search interface
 
-	datasheets         []datasheet // All datasheets under cwd
-	datasheetNames     []string    // All datasheet names (caching)
-	filteredDatasheets []string    // Filtered view on all datasheets
+	datasheets           []datasheet   // All datasheets under cwd
+	datasheetNames       []string      // All datasheet names (caching)
+	filteredDatasheets   []string      // Filtered view on all datasheets
+	loadDatasheetSpinner spinner.Model // Spinner to show while loading datasheets
+	datasheetsLoaded     bool          // Whether or not the datasheets are loaded or not
 
 	datasheetViewport viewport.Model // Viewport for the PDF content
 
@@ -108,6 +111,35 @@ func initialModel() model {
 	input := textinput.New()
 	input.Focus()
 
+	// TODO: set width/heigh to match terminal. this should also
+	//       be set in relation to the list of filenames also. they
+	//       should have some visually pleasing ratio set i imagine
+	viewp := viewport.New(60, 30)
+
+	loadDatasheetSpinner := spinner.New()
+	loadDatasheetSpinner.Spinner = spinner.Dot
+	loadDatasheetSpinner.Style = lipgloss.NewStyle().Foreground(lipgloss.Color("205"))
+
+	m := model{
+		input:                input,
+		datasheetsLoaded:     false,
+		loadDatasheetSpinner: loadDatasheetSpinner,
+		datasheetViewport:    viewp,
+		filterMode:           filenameFilterMode,
+	}
+
+	return m
+}
+
+// loadedDatasheetsMsg signals to the UI that the datasheets have been loaded.
+type loadedDatasheetsMsg struct {
+	datasheets     []datasheet
+	datasheetNames []string
+}
+
+// loadDatasheets loads the datasheets from disk. The UI shows a spinner while
+// this is happening so that nobody gets bored.
+func loadDatasheets(m model) loadedDatasheetsMsg {
 	var datasheets []datasheet
 	var datasheetNames []string
 
@@ -138,28 +170,19 @@ func initialModel() model {
 		return nil
 	})
 
-	// TODO: set width/heigh to match terminal. this should also
-	//       be set in relation to the list of filenames also. they
-	//       should have some visually pleasing ratio set i imagine
-	viewp := viewport.New(60, 30)
-	selectedDatasheet := datasheets[len(datasheets)-1].contents
-	viewp.SetContent(selectedDatasheet)
-
-	m := model{
-		input:              input,
-		datasheets:         datasheets,
-		datasheetNames:     datasheetNames,
-		filteredDatasheets: datasheetNames,
-		datasheetViewport:  viewp,
-		filterMode:         filenameFilterMode,
+	return loadedDatasheetsMsg{
+		datasheets:     datasheets,
+		datasheetNames: datasheetNames,
 	}
-
-	return m
 }
 
 // Init initialises the program.
 func (m model) Init() tea.Cmd {
-	return textinput.Blink
+	return tea.Batch(
+		func() tea.Msg { return loadDatasheets(m) },
+		textinput.Blink,
+		m.loadDatasheetSpinner.Tick,
+	)
 }
 
 // filterDatasheetNames filters datasheet names based on user input.
@@ -189,7 +212,16 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		cmds []tea.Cmd
 	)
 
-	if m.input.Focused() {
+	m.input, cmd = m.input.Update(msg)
+	cmds = append(cmds, cmd)
+
+	m.datasheetViewport, cmd = m.datasheetViewport.Update(msg)
+	cmds = append(cmds, cmd)
+
+	m.loadDatasheetSpinner, cmd = m.loadDatasheetSpinner.Update(msg)
+	cmds = append(cmds, cmd)
+
+	if m.input.Focused() && m.datasheetsLoaded {
 		m.filteredDatasheets = filterDatasheetNames(m)
 
 		// TODO: implement cursor for scrolling up/down filtered
@@ -202,6 +234,15 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	// TODO: handle terminal resizing
 	switch msg := msg.(type) {
+	case loadedDatasheetsMsg:
+		m.datasheets = msg.datasheets
+		m.datasheetNames = msg.datasheetNames
+		m.filteredDatasheets = msg.datasheetNames
+
+		selectedDatasheet := msg.datasheets[len(msg.datasheets)-1].contents
+		m.datasheetViewport.SetContent(selectedDatasheet)
+
+		m.datasheetsLoaded = true
 	case tea.KeyMsg:
 		switch msg.String() {
 		case "ctrl+c":
@@ -211,12 +252,6 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 	}
 
-	m.input, cmd = m.input.Update(msg)
-	cmds = append(cmds, cmd)
-
-	m.datasheetViewport, cmd = m.datasheetViewport.Update(msg)
-	cmds = append(cmds, cmd)
-
 	return m, tea.Batch(cmds...)
 }
 
@@ -224,8 +259,13 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 func (m model) View() string {
 	body := strings.Builder{}
 
-	// TODO: paginate / trim view to last 10 or something?
-	sheets := strings.Join(m.filteredDatasheets, "\n")
+	var sheets string
+	if !m.datasheetsLoaded {
+		sheets = fmt.Sprintf("%s gathering datasheets...", m.loadDatasheetSpinner.View())
+	} else {
+		// TODO: paginate / trim view to last 10 or something?
+		sheets = strings.Join(m.filteredDatasheets, "\n")
+	}
 
 	// TODO: style further with lipgloss, e.g. borders, margins, etc.
 	panes := lipgloss.JoinHorizontal(lipgloss.Left, sheets, m.datasheetViewport.View())