From ed8d357881ea1ef00ad28cd186481e97386249a0 Mon Sep 17 00:00:00 2001
From: Chris Cummer <chriscummer@me.com>
Date: Sun, 28 Apr 2019 20:43:39 -0700
Subject: [PATCH] Simplifies the use of MultiSourceWidget

Widgets that embed MultiSourceWidget no longer have to explicitly call
loadSources(). This is done as part of the set-up for MultiSourceWidget.
---
 modules/git/widget.go       |  1 -
 modules/mercurial/widget.go |  1 -
 modules/textfile/widget.go  |  1 -
 modules/twitter/widget.go   |  1 -
 wtf/multisource_widget.go   | 80 ++++++++++++++++++++++++-------------
 5 files changed, 52 insertions(+), 32 deletions(-)

diff --git a/modules/git/widget.go b/modules/git/widget.go
index 0b6ad89d..6373a7d0 100644
--- a/modules/git/widget.go
+++ b/modules/git/widget.go
@@ -50,7 +50,6 @@ func NewWidget(app *tview.Application, pages *tview.Pages, settings *Settings) *
 		settings: settings,
 	}
 
-	widget.LoadSources()
 	widget.SetDisplayFunction(widget.display)
 
 	widget.HelpfulWidget.SetView(widget.View)
diff --git a/modules/mercurial/widget.go b/modules/mercurial/widget.go
index 656047e8..ea95c989 100644
--- a/modules/mercurial/widget.go
+++ b/modules/mercurial/widget.go
@@ -45,7 +45,6 @@ func NewWidget(app *tview.Application, pages *tview.Pages, settings *Settings) *
 		settings: settings,
 	}
 
-	widget.LoadSources()
 	widget.SetDisplayFunction(widget.display)
 
 	widget.HelpfulWidget.SetView(widget.View)
diff --git a/modules/textfile/widget.go b/modules/textfile/widget.go
index 17bf277f..9acb3075 100644
--- a/modules/textfile/widget.go
+++ b/modules/textfile/widget.go
@@ -53,7 +53,6 @@ func NewWidget(app *tview.Application, pages *tview.Pages, settings *Settings) *
 	widget.settings.common.RefreshInterval = 0
 
 	widget.HelpfulWidget.SetView(widget.View)
-	widget.LoadSources()
 	widget.SetDisplayFunction(widget.display)
 	widget.View.SetWrap(true)
 	widget.View.SetWordWrap(true)
diff --git a/modules/twitter/widget.go b/modules/twitter/widget.go
index 2682e151..33dfb5c0 100644
--- a/modules/twitter/widget.go
+++ b/modules/twitter/widget.go
@@ -48,7 +48,6 @@ func NewWidget(app *tview.Application, pages *tview.Pages, settings *Settings) *
 
 	widget.HelpfulWidget.SetView(widget.View)
 
-	widget.LoadSources()
 	widget.SetDisplayFunction(widget.display)
 
 	widget.client = NewClient(settings)
diff --git a/wtf/multisource_widget.go b/wtf/multisource_widget.go
index 3123e6cf..6ddffdf1 100644
--- a/wtf/multisource_widget.go
+++ b/wtf/multisource_widget.go
@@ -14,16 +14,22 @@ type MultiSourceWidget struct {
 	Sources         []string
 }
 
+// NewMultiSourceWidget creates and returns an instance of MultiSourceWidget
 func NewMultiSourceWidget(moduleConfig *cfg.Common, singular, plural string) MultiSourceWidget {
-	return MultiSourceWidget{
+	widget := MultiSourceWidget{
 		moduleConfig: moduleConfig,
 		singular:     singular,
 		plural:       plural,
 	}
+
+	widget.loadSources()
+
+	return widget
 }
 
 /* -------------------- Exported Functions -------------------- */
 
+// CurrentSource returns the string representations of the currently-displayed source
 func (widget *MultiSourceWidget) CurrentSource() string {
 	if widget.Idx >= len(widget.Sources) {
 		return ""
@@ -32,7 +38,51 @@ func (widget *MultiSourceWidget) CurrentSource() string {
 	return widget.Sources[widget.Idx]
 }
 
-func (widget *MultiSourceWidget) LoadSources() {
+// Next displays the next source in the source list. If the current source is the last
+// source it wraps around to the first source
+func (widget *MultiSourceWidget) Next() {
+	widget.Idx = widget.Idx + 1
+	if widget.Idx == len(widget.Sources) {
+		widget.Idx = 0
+	}
+
+	if widget.DisplayFunction != nil {
+		widget.DisplayFunction()
+	}
+}
+
+// Prev displays the previous source in the source list. If the current source is the first
+// source, it wraps around to the last source
+func (widget *MultiSourceWidget) Prev() {
+	widget.Idx = widget.Idx - 1
+	if widget.Idx < 0 {
+		widget.Idx = len(widget.Sources) - 1
+	}
+
+	if widget.DisplayFunction != nil {
+		widget.DisplayFunction()
+	}
+}
+
+// SetDisplayFunction stores the function that should be called when the source is
+// changed. This is typically called from within the initializer for the struct that
+// embeds MultiSourceWidget
+//
+// Example:
+//
+//   widget := Widget{
+//     MultiSourceWidget: wtf.NewMultiSourceWidget(settings.common, "person", "people")
+//   }
+//
+//   widget.SetDisplayFunction(widget.display)
+//
+func (widget *MultiSourceWidget) SetDisplayFunction(displayFunc func()) {
+	widget.DisplayFunction = displayFunc
+}
+
+/* -------------------- Unexported Functions -------------------- */
+
+func (widget *MultiSourceWidget) loadSources() {
 	var empty []interface{}
 
 	single := widget.moduleConfig.Config.UString(widget.singular, "")
@@ -46,29 +96,3 @@ func (widget *MultiSourceWidget) LoadSources() {
 
 	widget.Sources = asStrs
 }
-
-func (widget *MultiSourceWidget) Next() {
-	widget.Idx = widget.Idx + 1
-	if widget.Idx == len(widget.Sources) {
-		widget.Idx = 0
-	}
-
-	if widget.DisplayFunction != nil {
-		widget.DisplayFunction()
-	}
-}
-
-func (widget *MultiSourceWidget) Prev() {
-	widget.Idx = widget.Idx - 1
-	if widget.Idx < 0 {
-		widget.Idx = len(widget.Sources) - 1
-	}
-
-	if widget.DisplayFunction != nil {
-		widget.DisplayFunction()
-	}
-}
-
-func (widget *MultiSourceWidget) SetDisplayFunction(displayFunc func()) {
-	widget.DisplayFunction = displayFunc
-}