Initial functionality

src/main.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"os"
+	"sort"
+
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+)
+
+// Individual Command Items Later Extracted
+type CmdItem struct {
+	CommandName        string `json:"command"`
+	CommandDescription string `json:"desc"`
+}
+
+// All commands
+type CmdMap map[string][]CmdItem
+
+// Read Json-File and return it
+func loadCommands(path string) (CmdMap, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+
+	var m CmdMap
+	if err := json.Unmarshal(data, &m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// Function Called when a subset of functions has been selected
+func showCommandList(app *tview.Application, lang string, cmds []CmdItem, langList *tview.List) {
+	cmdList := tview.NewList()
+	cmdList.SetBorder(true).SetTitle(fmt.Sprintf("%s commands", lang))
+
+	for _, c := range cmds {
+		c := c
+		cmdList.AddItem(c.CommandName, c.CommandDescription, 0, func() {
+			//fmt.Println(c.CommandName)
+			app.Suspend(func() {
+				fmt.Println(c.CommandName) // this now prints visibly
+			})
+			app.Stop()
+			os.Exit(0)
+		})
+	}
+
+	cmdList.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
+		if event.Rune() == 'b' || event.Key() == tcell.KeyEscape {
+			// Restore the language list
+			app.SetRoot(langList, true)
+			return nil
+		}
+		return event
+	})
+
+	app.SetRoot(cmdList, true)
+}
+
+// Main Function
+// Initialises the first page and starts app
+func main() {
+	commands, err := loadCommands("data/commands.json")
+	if err != nil {
+		log.Fatalf("Cannot load commands file: %v", err)
+	}
+
+	app := tview.NewApplication()
+
+	// Sort alphabetically
+	langs := make([]string, 0, len(commands))
+	for lang := range commands {
+		langs = append(langs, lang)
+	}
+	sort.Strings(langs)
+
+	langList := tview.NewList()
+	langList.SetBorder(true).SetTitle("Select a topic")
+
+	for _, lang := range langs {
+		lang := lang // capture loop variable
+		langList.AddItem(lang, "", 0, func() {
+			showCommandList(app, lang, commands[lang], langList)
+		})
+	}
+
+	if err := app.SetRoot(langList, true).Run(); err != nil {
+		log.Fatalf("Error initialising TUI: %v", err)
+	}
+}