Initial Commit

cmd/main.go

@@ -0,0 +1,108 @@
+package main
+
+import (
+	"fmt"
+	"math"
+
+	"github.com/expr-lang/expr"
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+)
+
+func main() {
+	app := tview.NewApplication()
+
+	env := map[string]any{
+		"abs":   math.Abs,
+		"acos":  math.Acos,
+		"asin":  math.Asin,
+		"atan":  math.Atan,
+		"atan2": math.Atan2,
+		"ceil":  math.Ceil,
+		"cos":   math.Cos,
+		"cosh":  math.Cosh,
+		"exp":   math.Exp,
+		"floor": math.Floor,
+		"log":   math.Log,
+		"log10": math.Log10,
+		"max":   math.Max,
+		"min":   math.Min,
+		"mod":   math.Mod,
+		"pow":   math.Pow,
+		"round": math.Round,
+		"sin":   math.Sin,
+		"sinh":  math.Sinh,
+		"sqrt":  math.Sqrt,
+		"tan":   math.Tan,
+		"tanh":  math.Tanh,
+		"pi":    math.Pi,
+		"e":     math.E,
+	}
+
+	title := tview.NewTextView()
+	title.SetText("🧮 [::b]Math Expression Evaluator[-]")
+	title.SetTextAlign(tview.AlignCenter)
+	title.SetDynamicColors(true)
+	title.SetBorder(true)
+	title.SetBorderColor(tcell.ColorLightBlue)
+
+	result := tview.NewTextView()
+	result.SetDynamicColors(true)
+	result.SetWrap(true)
+	result.SetChangedFunc(func() { app.Draw() })
+	result.SetBorder(true)
+	result.SetTitle("Result")
+	result.SetTitleAlign(tview.AlignLeft)
+
+	help := tview.NewTextView()
+	help.SetText("[yellow]Functions: sqrt, pow, abs, sin, cos, tan...\nConstants: pi, e")
+	help.SetDynamicColors(true)
+	help.SetWrap(true)
+	help.SetBorder(true)
+	help.SetTitle("Help")
+	help.SetTitleAlign(tview.AlignLeft)
+
+	input := tview.NewInputField()
+	input.SetLabel("Expression: ")
+	input.SetFieldWidth(60)
+	input.SetDoneFunc(func(key tcell.Key) {
+		if key == tcell.KeyEnter {
+			exprStr := input.GetText()
+
+			program, err := expr.Compile(exprStr, expr.Env(env))
+			if err != nil {
+				result.SetText(fmt.Sprintf("[red]Compile error: %v", err))
+				return
+			}
+			output, err := expr.Run(program, env)
+			if err != nil {
+				result.SetText(fmt.Sprintf("[red]Runtime error: %v", err))
+				return
+			}
+			result.SetText(fmt.Sprintf("[green]Result: %v", output))
+		}
+	})
+	input.SetBorder(true)
+	input.SetTitle("Input")
+	input.SetTitleAlign(tview.AlignLeft)
+
+	mainFlex := tview.NewFlex()
+	mainFlex.SetDirection(tview.FlexRow)
+	mainFlex.AddItem(title, 3, 1, false)
+	mainFlex.AddItem(input, 5, 0, true)
+	mainFlex.AddItem(result, 5, 0, false)
+	mainFlex.AddItem(help, 3, 1, false)
+
+	app.SetRoot(mainFlex, true)
+	app.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
+		if event.Key() == tcell.KeyEsc || event.Key() == tcell.KeyCtrlC {
+			app.Stop()
+			return nil
+		}
+		return event
+	})
+
+	if err := app.Run(); err != nil {
+		panic(err)
+	}
+}