Set column widths from sidebarWidth config value

Reads from config file or defaults to 1 column

README.md

@@ -24,7 +24,11 @@ Getting started
         "slack_token": "yourslacktokenhere",
 
         // add the following to use light theme, default is dark
-        "theme": "light"
+        "theme": "light",
+
+        // Set the width of the channel list sidebar. Must be between 1 and 11
+        // as the entire width of the screen is 12 columns.
+        "sidebar_width": 3
     }
     ```
 

config/config.go

@@ -10,14 +10,16 @@ import (
 
 // Config is the definition of a Config struct
 type Config struct {
-	SlackToken string `json:"slack_token"`
-	Theme      string `json:"theme"`
+	SlackToken   string `json:"slack_token"`
+	Theme        string `json:"theme"`
+	SidebarWidth int    `json:"sidebar_width"`
 }
 
 // NewConfig loads the config file and returns a Config struct
 func NewConfig(filepath string) (*Config, error) {
 	cfg := Config{
-		Theme: "dark",
+		Theme:        "dark",
+		SidebarWidth: 1,
 	}
 
 	file, err := os.Open(filepath)

main.go

@@ -68,15 +68,17 @@ func main() {
 	// Create context
 	ctx := context.CreateAppContext(flgConfig)
 
+	mainWidth := 12 - ctx.Config.SidebarWidth
+
 	// Setup body
 	termui.Body.AddRows(
 		termui.NewRow(
-			termui.NewCol(1, 0, ctx.View.Channels),
-			termui.NewCol(11, 0, ctx.View.Chat),
+			termui.NewCol(ctx.Config.SidebarWidth, 0, ctx.View.Channels),
+			termui.NewCol(mainWidth, 0, ctx.View.Chat),
 		),
 		termui.NewRow(
-			termui.NewCol(1, 0, ctx.View.Mode),
-			termui.NewCol(11, 0, ctx.View.Input),
+			termui.NewCol(ctx.Config.SidebarWidth, 0, ctx.View.Mode),
+			termui.NewCol(mainWidth, 0, ctx.View.Input),
 		),
 	)
 	termui.Body.Align()