package app

import (
	"bytes"
	"testing"
)

func TestCursorShifterCUP(t *testing.T) {
	cs := newCursorShifter(1)
	got := cs.Shift([]byte("\x1b[H"))
	want := []byte("\x1b[2;1H")
	if !bytes.Equal(got, want) {
		t.Fatalf("CUP home: got %q want %q", got, want)
	}
}

func TestCursorShifterCUPRowCol(t *testing.T) {
	cs := newCursorShifter(1)
	got := cs.Shift([]byte("\x1b[10;5H"))
	if string(got) != "\x1b[11;5H" {
		t.Fatalf("CUP 10;5: got %q", got)
	}
}

func TestCursorShifterVPA(t *testing.T) {
	cs := newCursorShifter(1)
	got := cs.Shift([]byte("\x1b[7d"))
	if string(got) != "\x1b[8d" {
		t.Fatalf("VPA 7: got %q", got)
	}
}

func TestCursorShifterDECSTBM(t *testing.T) {
	cs := newCursorShifter(1)
	got := cs.Shift([]byte("\x1b[2;20r"))
	if string(got) != "\x1b[3;21r" {
		t.Fatalf("DECSTBM: got %q", got)
	}
}

func TestCursorShifterPrivateCSIPassthrough(t *testing.T) {
	cs := newCursorShifter(1)
	// Alt-screen toggle — private CSI.
	got := cs.Shift([]byte("\x1b[?1049h"))
	if string(got) != "\x1b[?1049h" {
		t.Fatalf("alt-screen: got %q", got)
	}
}

func TestCursorShifterSGRPassthrough(t *testing.T) {
	cs := newCursorShifter(1)
	got := cs.Shift([]byte("\x1b[1;31mhello\x1b[0m"))
	if string(got) != "\x1b[1;31mhello\x1b[0m" {
		t.Fatalf("SGR: got %q", got)
	}
}

func TestCursorShifterStraddleChunks(t *testing.T) {
	cs := newCursorShifter(1)
	a := cs.Shift([]byte("\x1b["))
	b := cs.Shift([]byte("5;3H"))
	got := string(a) + string(b)
	if got != "\x1b[6;3H" {
		t.Fatalf("straddle: got %q", got)
	}
}

func TestCursorShifterOSCNotRewritten(t *testing.T) {
	cs := newCursorShifter(1)
	// OSC body containing what looks like a CSI cursor move — should
	// NOT be rewritten.
	in := []byte("\x1b]0;\x1b[5;3Htitle\x07")
	got := cs.Shift(in)
	if string(got) != string(in) {
		t.Fatalf("OSC: got %q want %q", got, in)
	}
}