package world

import (
	"testing"

	"github.com/stretchr/testify/require"
)

func TestClampCameraNoWrapViewport_ClampsToKeepViewportInsideWorld(t *testing.T) {
	t.Parallel()

	worldW := 100 * SCALE
	worldH := 100 * SCALE
	zoomFp := SCALE // 1.0x

	// viewport 40px => span 40 units => half 20.
	viewportW, viewportH := 40, 40

	// Too far left/up => clamp to minCam=20
	cx, cy := ClampCameraNoWrapViewport(
		0, 0,
		viewportW, viewportH,
		zoomFp,
		worldW, worldH,
	)
	require.Equal(t, 20*SCALE, cx)
	require.Equal(t, 20*SCALE, cy)

	// Too far right/down => clamp to maxCam=world-half=80
	cx, cy = ClampCameraNoWrapViewport(
		99*SCALE, 99*SCALE,
		viewportW, viewportH,
		zoomFp,
		worldW, worldH,
	)
	require.Equal(t, 80*SCALE, cx)
	require.Equal(t, 80*SCALE, cy)

	// Inside range => unchanged
	cx, cy = ClampCameraNoWrapViewport(
		50*SCALE, 60*SCALE,
		viewportW, viewportH,
		zoomFp,
		worldW, worldH,
	)
	require.Equal(t, 50*SCALE, cx)
	require.Equal(t, 60*SCALE, cy)
}

func TestClampCameraNoWrapViewport_WhenViewportLargerThanWorld_ForcesCenter(t *testing.T) {
	t.Parallel()

	worldW := 50 * SCALE
	worldH := 50 * SCALE
	zoomFp := SCALE

	// viewport 60px => span 60 units > world 50
	viewportW, viewportH := 60, 60

	cx, cy := ClampCameraNoWrapViewport(
		0, 0,
		viewportW, viewportH,
		zoomFp,
		worldW, worldH,
	)

	require.Equal(t, worldW/2, cx)
	require.Equal(t, worldH/2, cy)
}

func TestWorldClampRenderParamsNoWrap_UsesViewportClamp(t *testing.T) {
	t.Parallel()

	w := NewWorld(100, 100)

	p := RenderParams{
		ViewportWidthPx:  40,
		ViewportHeightPx: 40,
		MarginXPx:        10,
		MarginYPx:        10,
		CameraZoom:       1.0,
		CameraXWorldFp:   0,
		CameraYWorldFp:   0,
		Options:          &RenderOptions{DisableWrapScroll: true},
	}

	w.ClampRenderParamsNoWrap(&p)

	// viewport half is 20, not 30 (margins ignored)
	require.Equal(t, 20*SCALE, p.CameraXWorldFp)
	require.Equal(t, 20*SCALE, p.CameraYWorldFp)
}