package world

import (
	"testing"

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

// rendererTestCase is a generic table-driven renderer test scaffold.
// Replace invoke with the real renderer call once the renderer exists.
type rendererTestCase struct {
	name string

	// setup prepares the world and optional environment overrides.
	setup func(t *testing.T, env *rendererTestEnv)

	// invoke calls the renderer under test.
	invoke func(t *testing.T, env *rendererTestEnv)

	// verify checks the produced fake drawer log.
	verify func(t *testing.T, env *rendererTestEnv)
}

func runRendererTestCases(t *testing.T, cases []rendererTestCase) {
	t.Helper()

	for _, tc := range cases {
		tc := tc
		t.Run(tc.name, func(t *testing.T) {
			env := newRendererTestEnv()

			if tc.setup != nil {
				tc.setup(t, env)
			}

			require.NotNil(t, tc.invoke, "renderer test case must define invoke")
			require.NotNil(t, tc.verify, "renderer test case must define verify")

			tc.invoke(t, env)
			tc.verify(t, env)
		})
	}
}

// TestRenderer_Template_PointCases is a scaffold for future point renderer tests.
func TestRenderer_Template_PointCases(t *testing.T) {
	t.Parallel()

	runRendererTestCases(t, []rendererTestCase{
		{
			name: "point fully inside viewport",
			setup: func(t *testing.T, env *rendererTestEnv) {
				worldMustAddPoint(t, env.world, 5, 5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "point visible only in horizontal margin copy",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewport(160, 40)
				worldMustAddPoint(t, env.world, 0.1, 5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "point visible only in vertical margin copy",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewport(40, 160)
				worldMustAddPoint(t, env.world, 5, 0.1)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "point duplicated across torus corner with independent margins",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewportAndMargins(120, 60, 30, 10)
				worldMustAddPoint(t, env.world, 0.1, 0.1)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
	})
}

// TestRenderer_Template_LineCases is a scaffold for future line renderer tests.
func TestRenderer_Template_LineCases(t *testing.T) {
	t.Parallel()

	runRendererTestCases(t, []rendererTestCase{
		{
			name: "line fully inside viewport",
			setup: func(t *testing.T, env *rendererTestEnv) {
				worldMustAddLine(t, env.world, 2, 2, 8, 2)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "line wrap copy across x edge",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewport(160, 40)
				worldMustAddLine(t, env.world, 9, 5, 1, 5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "line wrap copy across y edge",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewport(40, 160)
				worldMustAddLine(t, env.world, 5, 9, 5, 1)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "line tie case uses deterministic wrapped representation",
			setup: func(t *testing.T, env *rendererTestEnv) {
				worldMustAddLine(t, env.world, 1, 5, 6, 5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
	})
}

// TestRenderer_Template_CircleCases is a scaffold for future circle renderer tests.
func TestRenderer_Template_CircleCases(t *testing.T) {
	t.Parallel()

	runRendererTestCases(t, []rendererTestCase{
		{
			name: "circle fully inside viewport",
			setup: func(t *testing.T, env *rendererTestEnv) {
				worldMustAddCircle(t, env.world, 5, 5, 1)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "circle duplicated across horizontal edge",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewport(160, 40)
				worldMustAddCircle(t, env.world, 0.2, 5, 0.5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "circle duplicated across vertical edge",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewport(40, 160)
				worldMustAddCircle(t, env.world, 5, 0.2, 0.5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
		{
			name: "circle duplicated across corner with asymmetric margins",
			setup: func(t *testing.T, env *rendererTestEnv) {
				env.setViewportAndMargins(120, 60, 30, 10)
				worldMustAddCircle(t, env.world, 0.2, 0.2, 0.5)
			},
			invoke: func(t *testing.T, env *rendererTestEnv) {
				t.Skip("replace with actual renderer call")
			},
			verify: func(t *testing.T, env *rendererTestEnv) {
				requireNoDrawerCommands(t, env.drawer)
			},
		},
	})
}