import { createShapeId } from '@tldraw/editor'
import { vi } from 'vitest'
import { createDrawSegments } from '../lib/utils/test-helpers'
import { TestEditor } from './TestEditor'

let editor: TestEditor

vi.useFakeTimers()

const ids = {
	box1: createShapeId('box1'),
	box2: createShapeId('box2'),
	box3: createShapeId('box3'),
	box4: createShapeId('box4'),
	draw1: createShapeId('draw1'),
	frame1: createShapeId('frame1'),
	group1: createShapeId('group1'),
}

beforeEach(() => {
	editor = new TestEditor()
	editor.createShapes([
		{
			id: ids.box1,
			type: 'geo',
			x: 0,
			y: 0,
			props: {
				fill: 'none',
			},
		},
		{
			id: ids.box2,
			type: 'geo',
			x: 75, // overlapping box1
			y: 75,
			props: {
				fill: 'solid',
			},
		},
		{
			id: ids.box3,
			type: 'geo',
			x: 300,
			y: 300,
			props: {
				fill: 'solid',
			},
		},
		{
			id: ids.frame1,
			type: 'frame',
			x: 300,
			y: 0,
			props: {
				w: 100,
				h: 100,
			},
		},
		{
			id: ids.box4,
			type: 'geo',
			parentId: ids.frame1,
			x: 50,
			y: 50, // clipped by frame
			props: {
				fill: 'solid',
			},
		},
		{
			id: ids.draw1,
			type: 'draw',
			x: 0,
			y: 300,
			props: {
				segments: createDrawSegments([
					[
						{ x: 0, y: 0 },
						{ x: 2, y: 50 },
						{ x: 10, y: 100 },
						{ x: 48, y: 100 },
						{ x: 100, y: 100 },
					],
				]),
			},
		},
	])
})

afterEach(() => {
	editor?.dispose()
})

describe('When clicking', () => {
	it('Selects the tool, adds the hovered shapes to the editor.erasingShapeIds array on pointer down, deletes them on pointer up, restores on undo and deletes again on redo', () => {
		editor.setCurrentTool('eraser')

		// Starts in idle
		editor.expectToBeIn('eraser.idle')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(0, 0) // near enough to box1

		// Enters the pointing state
		editor.expectToBeIn('eraser.pointing')

		// Sets the erasingShapeIds array
		expect(editor.getErasingShapeIds()).toEqual([ids.box1])

		editor.pointerUp()

		const shapesAfterCount = editor.getCurrentPageShapes().length

		// Deletes the erasing shapes
		expect(editor.getShape(ids.box1)).toBeUndefined()
		expect(shapesAfterCount).toBe(shapesBeforeCount - 1)

		// Also empties the erasingShapeIds array
		expect(editor.getErasingShapeIds()).toEqual([])

		// Returns to idle
		editor.expectToBeIn('eraser.idle')

		editor.undo()

		expect(editor.getShape(ids.box1)).toBeDefined()
		expect(editor.getCurrentPageShapes().length).toBe(shapesBeforeCount)

		editor.redo()

		expect(editor.getShape(ids.box1)).toBeUndefined()
		expect(editor.getCurrentPageShapes().length).toBe(shapesBeforeCount - 1)
	})

	it('Erases all shapes under the cursor on click', () => {
		editor.setCurrentTool('eraser')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(99, 99) // next to box1 AND in box2

		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.box1, ids.box2]))

		editor.pointerUp()

		expect(editor.getShape(ids.box1)).toBeUndefined()
		expect(editor.getShape(ids.box2)).toBeUndefined()

		const shapesAfterCount = editor.getCurrentPageShapes().length
		expect(shapesAfterCount).toBe(shapesBeforeCount - 2)
	})

	it("Erases a group when clicking on the group's child", () => {
		editor.groupShapes([ids.box2, ids.box3], { groupId: ids.group1 })
		editor.setCurrentTool('eraser')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(350, 350) // in box3

		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.group1]))

		editor.pointerUp()

		const shapesAfterCount = editor.getCurrentPageShapes().length

		expect(editor.getShape(ids.box2)).toBeUndefined()
		expect(editor.getShape(ids.box3)).toBeUndefined()
		expect(editor.getShape(ids.group1)).toBeUndefined()

		expect(shapesAfterCount).toBe(shapesBeforeCount - 3)
	})

	it('Does not erase a group when clicking on the group itself', () => {
		editor.groupShapes([ids.box2, ids.box3], { groupId: ids.group1 })
		editor.setCurrentTool('eraser')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(275, 275) // in between box2 AND box3, so over of the new group

		editor.pointerUp()

		const shapesAfterCount = editor.getCurrentPageShapes().length
		expect(shapesAfterCount).toBe(shapesBeforeCount)
	})

	it('Stops erasing when it reaches a frame when the frame was not was the top-most hovered shape', () => {
		editor.setCurrentTool('eraser')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(375, 75) // inside of the box4 shape inside of box3

		editor.pointerUp()

		const shapesAfterCount = editor.getCurrentPageShapes().length
		expect(shapesAfterCount).toBe(shapesBeforeCount - 1)

		// Erases the child but does not erase the frame
		expect(editor.getShape(ids.box4)).toBeUndefined()
		expect(editor.getShape(ids.frame1)).toBeDefined()
	})

	it('Erases a frame only when its clicked on the edge', () => {
		editor.setCurrentTool('eraser')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(325, 25) // directly on frame1, not its children

		editor.pointerUp() // without dragging!

		const shapesAfterCount = editor.getCurrentPageShapes().length
		expect(shapesAfterCount).toBe(shapesBeforeCount)

		// Erases BOTH the frame and its child
		expect(editor.getShape(ids.box4)).toBeDefined()
		expect(editor.getShape(ids.frame1)).toBeDefined()
	})

	it('Only erases masked shapes when pointer is inside the mask', () => {
		editor.setCurrentTool('eraser')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(425, 125) // inside of box4's bounds, but outside of its parent's mask

		editor.pointerUp() // without dragging!

		const shapesAfterCount = editor.getCurrentPageShapes().length
		expect(shapesAfterCount).toBe(shapesBeforeCount)

		// Erases NEITHER the frame nor its child
		expect(editor.getShape(ids.box4)).toBeDefined()
		expect(editor.getShape(ids.frame1)).toBeDefined()
	})

	it('Clears erasing ids and does not erase shapes on cancel', () => {
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(0, 0) // in box1
		editor.expectToBeIn('eraser.pointing')

		expect(editor.getErasingShapeIds()).toEqual([ids.box1])

		editor.cancel()

		editor.pointerUp()

		const shapesAfterCount = editor.getCurrentPageShapes().length

		editor.expectToBeIn('eraser.idle')

		// Does NOT erase the shape
		expect(editor.getErasingShapeIds()).toEqual([])
		expect(editor.getShape(ids.box1)).toBeDefined()
		expect(shapesAfterCount).toBe(shapesBeforeCount)
	})

	it('Clears erasing ids and does not erase shapes on interrupt', () => {
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.pointerDown(0, 0) // near to box1
		editor.expectToBeIn('eraser.pointing')

		expect(editor.getErasingShapeIds()).toEqual([ids.box1])

		editor.interrupt()

		editor.pointerUp()

		const shapesAfterCount = editor.getCurrentPageShapes().length

		editor.expectToBeIn('eraser.idle')

		// Does NOT erase the shape
		expect(editor.getErasingShapeIds()).toEqual([])
		expect(editor.getShape(ids.box1)).toBeDefined()
		expect(shapesAfterCount).toBe(shapesBeforeCount)
	})
})

describe('When clicking and dragging', () => {
	it('Enters erasing state on pointer move, adds contacted shapes to the apps.erasingShapeIds array, deletes them and clears erasingShapeIds  on pointer up, restores shapes on undo and deletes again on redo', () => {
		editor.setCurrentTool('eraser')

		editor.expectToBeIn('eraser.idle')

		editor.pointerDown(-100, -100) // outside of any shapes

		editor.expectToBeIn('eraser.pointing')
		expect(editor.getInstanceState().scribbles.length).toBe(0)

		editor.pointerMove(50, 50) // inside of box1

		editor.expectToBeIn('eraser.erasing')

		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)

		expect(editor.getErasingShapeIds()).toEqual([ids.box1])

		// editor.pointerUp()
		// editor.expectToBeIn('eraser.idle')
		// expect(editor.erasingShapeIds).toEqual([])
		// expect(editor.getShape(ids.box1)).not.toBeDefined()

		// editor.undo()

		// expect(editor.erasingShapeIds).toEqual([])
		// expect(editor.getShape(ids.box1)).toBeDefined()

		// editor.redo()

		// expect(editor.erasingShapeIds).toEqual([])
		// expect(editor.getShape(ids.box1)).not.toBeDefined()
	})

	it('Clears erasing ids and does not erase shapes on cancel', () => {
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')
		editor.pointerDown(-100, -100) // outside of any shapes
		editor.pointerMove(50, 50) // inside of box1
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		expect(editor.getErasingShapeIds()).toEqual([ids.box1])
		editor.cancel()
		editor.expectToBeIn('eraser.idle')
		expect(editor.getErasingShapeIds()).toEqual([])
		expect(editor.getShape(ids.box1)).toBeDefined()
	})

	it('Excludes a group if it was hovered when the drag started, but erases its children', () => {
		editor.groupShapes([ids.box2, ids.box3], { groupId: ids.group1 })
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')
		editor.pointerDown(275, 275) // in between box2 AND box3, so over of the new group
		editor.pointerMove(280, 280) // still in the gap between children
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		expect(editor.getErasingShapeIds()).toEqual([])
		// Moving to (0,0) crosses through box2 (child of the group) and box1
		editor.pointerMove(0, 0)
		// box2 is now erased as a child shape (not resolved to the excluded group)
		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.box1, ids.box2]))
		expect(editor.getShape(ids.box1)).toBeDefined()
		editor.pointerUp()
		// box1 and box2 are deleted; the group auto-dissolves since it only has one child left
		expect(editor.getShape(ids.box1)).not.toBeDefined()
		expect(editor.getShape(ids.box2)).not.toBeDefined()
		expect(editor.getShape(ids.group1)).not.toBeDefined()
		// box3 survives (it was reparented when the group dissolved)
		expect(editor.getShape(ids.box3)).toBeDefined()
	})

	it('Erases child shapes when starting drag inside a group and dragging over them', () => {
		editor.groupShapes([ids.box2, ids.box3], { groupId: ids.group1 })
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')
		// Start inside the group bounds (between box2 and box3)
		editor.pointerDown(275, 275)
		// Drag directly over box3
		editor.pointerMove(350, 350)
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		// box3 should be marked for erasing as a child of the excluded group
		expect(editor.getErasingShapeIds()).toEqual([ids.box3])
		editor.pointerUp()
		// box3 is deleted; the group auto-dissolves since it only has one child left
		expect(editor.getShape(ids.box3)).not.toBeDefined()
		expect(editor.getShape(ids.group1)).not.toBeDefined()
		// box2 survives (reparented when the group dissolved)
		expect(editor.getShape(ids.box2)).toBeDefined()
	})

	it('Erases the whole group when starting drag outside of it', () => {
		editor.groupShapes([ids.box2, ids.box3], { groupId: ids.group1 })
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')
		// Start outside the group (avoiding box1 which is at 0,0)
		editor.pointerDown(150, -100)
		// Drag over box2 (child of group)
		editor.pointerMove(150, 125)
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		// The whole group should be erased since we started outside
		expect(editor.getErasingShapeIds()).toEqual([ids.group1])
		editor.pointerUp()
		expect(editor.getShape(ids.group1)).not.toBeDefined()
		expect(editor.getShape(ids.box2)).not.toBeDefined()
		expect(editor.getShape(ids.box3)).not.toBeDefined()
	})

	it('Excludes a frame if it was hovered when the drag started', () => {
		editor.setCurrentTool('eraser')
		editor.pointerDown(325, 25) // directly on frame1, not its children
		editor.pointerMove(350, 375) // still in the frame, passing through box3
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		expect(editor.getErasingShapeIds()).toEqual([ids.box3])
		editor.pointerUp()
		expect(editor.getShape(ids.frame1)).toBeDefined()
		expect(editor.getShape(ids.box3)).not.toBeDefined()
	})

	it('Only erases masked shapes when pointer is inside the mask', () => {
		editor.setCurrentTool('eraser')
		editor.pointerMove(425, 0)
		editor.pointerDown() // Above the masked part of box3
		expect(editor.getErasingShapeIds()).toEqual([])
		editor.pointerMove(425, 500) // Through the masked part of box3
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		expect(editor.getErasingShapeIds()).toEqual([])
		editor.pointerUp()
		expect(editor.getShape(ids.box3)).toBeDefined()

		editor.pointerMove(375, 0)
		editor.pointerDown() // Above the not-masked part of box3
		editor.pointerMove(375, 500) // Through the masked part of box3
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		expect(editor.getErasingShapeIds()).toEqual([ids.box3])
		editor.pointerUp()
		expect(editor.getShape(ids.box3)).not.toBeDefined()
	})

	it('Does nothing on interrupt, allowing for a pinch during the erasing session', () => {
		editor.setCurrentTool('eraser')
		editor.pointerDown(-100, -100)
		editor.pointerMove(50, 50)
		editor.interrupt()
		editor.expectToBeIn('eraser.erasing')
	})

	it('Starts a scribble on pointer down, updates it on pointer move, stops it on exit', () => {
		editor.setCurrentTool('eraser')
		editor.pointerDown(-100, -100)
		expect(editor.getInstanceState().scribbles.length).toBe(0)
		editor.pointerMove(50, 50)
		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		editor.pointerMove(50, 50)
		editor.pointerMove(51, 50)
		editor.pointerMove(52, 50)
		editor.pointerMove(53, 50)
		editor.pointerUp()
		expect(editor.getInstanceState().scribbles.length).toBe(1)
	})
})

describe('Does not erase hollow shapes on click', () => {
	it('Returns to select on cancel', () => {
		editor.selectAll().deleteShapes(editor.getSelectedShapes())
		expect(editor.getCurrentPageShapes().length).toBe(0)
		editor.createShape({
			id: createShapeId(),
			type: 'geo',
		})
		editor.setCurrentTool('eraser')
		editor.pointerMove(50, 50)
		editor.pointerDown()
		expect(editor.getErasingShapeIds()).toEqual([])
		editor.pointerUp()
		expect(editor.getCurrentPageShapes().length).toBe(1)
	})
})

// Not yet implemented
describe('When shift clicking', () => {
	it.todo('Erases a line between the previous clicked point and the current point')
	it.todo('Clears the previous clicked point when leaving / re-entering the eraser tool')
})

describe('When holding meta/ctrl key (accel key)', () => {
	it('Only erases the top shape hit when clicking with accel key held', () => {
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')

		const shapesBeforeCount = editor.getCurrentPageShapes().length

		editor.keyDown('Meta')
		editor.pointerDown(99, 99) // next to box1 AND in box2

		expect(editor.getErasingShapeIds()).toEqual([ids.box2])

		editor.pointerUp()

		expect(editor.getShape(ids.box1)).toBeDefined()
		expect(editor.getShape(ids.box2)).toBeUndefined()

		const shapesAfterCount = editor.getCurrentPageShapes().length
		expect(shapesAfterCount).toBe(shapesBeforeCount - 1)

		editor.keyUp('Meta')
	})

	it('Erases all hit shapes once an accel pointer becomes a drag', () => {
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')

		editor.keyDown('Meta')
		editor.pointerDown(99, 99) // next to box1 AND in box2

		expect(editor.getErasingShapeIds()).toEqual([ids.box2])

		editor.pointerMove(350, 350) // in box3
		editor.expectToBeIn('eraser.erasing')
		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.box1, ids.box2, ids.box3]))

		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)
		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.box1, ids.box2, ids.box3]))

		editor.pointerUp()

		expect(editor.getShape(ids.box1)).toBeUndefined()
		expect(editor.getShape(ids.box2)).toBeUndefined()
		expect(editor.getShape(ids.box3)).toBeUndefined()

		editor.keyUp('Meta')
	})

	it('Still erases normally when accel key is released during erasing', () => {
		editor.setCurrentTool('eraser')
		editor.expectToBeIn('eraser.idle')

		editor.pointerDown(-100, -100) // outside of any shapes
		editor.pointerMove(99, 99) // next to box1 AND in box2

		vi.advanceTimersByTime(16)
		expect(editor.getInstanceState().scribbles.length).toBe(1)

		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.box1, ids.box2]))

		editor.keyDown('Meta')
		editor.keyUp('Meta')
		editor.pointerMove(350, 350) // in box3

		expect(new Set(editor.getErasingShapeIds())).toEqual(new Set([ids.box1, ids.box2, ids.box3]))

		editor.pointerUp()

		expect(editor.getShape(ids.box1)).toBeUndefined()
		expect(editor.getShape(ids.box2)).toBeUndefined()
		expect(editor.getShape(ids.box3)).toBeUndefined()
	})
})

describe('Hold accel to temporarily erase from the draw / highlight tool', () => {
	for (const tool of ['draw', 'highlight'] as const) {
		describe(`from ${tool}`, () => {
			it(`holding accel alone does not switch tools`, () => {
				editor.setCurrentTool(tool)
				editor.expectToBeIn(`${tool}.idle`)

				editor.keyDown('Meta')

				// No tool switch on key down — the switch only happens on pointer down.
				editor.expectToBeIn(`${tool}.idle`)
				expect(editor.getCurrentToolId()).toBe(tool)

				editor.keyUp('Meta')
				editor.expectToBeIn(`${tool}.idle`)
			})

			it(`accel + click in idle goes straight into eraser.pointing with ${tool} masked`, () => {
				editor.setCurrentTool(tool)
				editor.keyDown('Meta')

				editor.pointerDown(99, 99) // next to box1 AND in box2

				editor.expectToBeIn('eraser.pointing')
				expect(editor.getCurrentTool().id).toBe('eraser')
				expect(editor.getCurrentToolId()).toBe(tool)
				expect(editor.getErasingShapeIds()).toEqual([ids.box2])
			})

			it(`accel + click + release with accel held returns to eraser.idle, masked as ${tool}`, () => {
				editor.setCurrentTool(tool)
				editor.keyDown('Meta')

				const shapesBefore = editor.getCurrentPageShapes().length
				editor.pointerDown(99, 99)
				editor.pointerUp()

				expect(editor.getCurrentPageShapes().length).toBe(shapesBefore - 1)
				expect(editor.getShape(ids.box1)).toBeDefined()
				expect(editor.getShape(ids.box2)).toBeUndefined()

				editor.expectToBeIn('eraser.idle')
				expect(editor.getCurrentTool().id).toBe('eraser')
				expect(editor.getCurrentToolId()).toBe(tool)
			})

			it(`releasing accel after a transient erase returns to ${tool}`, () => {
				editor.setCurrentTool(tool)
				editor.keyDown('Meta')

				editor.pointerDown(99, 99)
				editor.pointerUp()
				editor.expectToBeIn('eraser.idle')

				editor.keyUp('Meta')
				editor.expectToBeIn(`${tool}.idle`)
				expect(editor.getCurrentToolId()).toBe(tool)
			})

			it(`release event on transient click returns to ${tool}`, () => {
				editor.setCurrentTool(tool)
				editor.keyDown('Meta')

				editor.pointerDown(99, 99)
				editor.expectToBeIn('eraser.pointing')
				expect(editor.inputs.getAccelKey()).toBe(true)

				editor.pointerUp(99, 99, { accelKey: false, metaKey: false, ctrlKey: false })
				editor.expectToBeIn(`${tool}.idle`)
				expect(editor.getCurrentToolId()).toBe(tool)
			})

			it(`releasing accel mid-erase does not yank back; pointer up returns to ${tool}`, () => {
				editor.setCurrentTool(tool)
				editor.keyDown('Meta')

				editor.pointerDown(99, 99)
				editor.expectToBeIn('eraser.pointing')
				editor.pointerMove(350, 350)
				editor.expectToBeIn('eraser.erasing')
				expect(new Set(editor.getErasingShapeIds())).toEqual(
					new Set([ids.box1, ids.box2, ids.box3])
				)

				expect(editor.getCurrentTool().id).toBe('eraser')
				expect(editor.inputs.getAccelKey()).toBe(true)

				editor.pointerUp(350, 350, { accelKey: false, metaKey: false, ctrlKey: false })
				editor.expectToBeIn(`${tool}.idle`)
				expect(editor.getCurrentToolId()).toBe(tool)
				expect(editor.getShape(ids.box1)).toBeUndefined()
				expect(editor.getShape(ids.box2)).toBeUndefined()
				expect(editor.getShape(ids.box3)).toBeUndefined()
			})

			it(`accel pressed mid-stroke does not switch tools`, () => {
				editor.setCurrentTool(tool)
				editor.pointerDown(0, 0)
				editor.expectToBeIn(`${tool}.drawing`)

				editor.keyDown('Meta')
				editor.expectToBeIn(`${tool}.drawing`)

				editor.keyUp('Meta')
				editor.pointerUp()
			})

			it(`shift + accel + click does not switch (preserves shift+cmd straight-line snap)`, () => {
				editor.setCurrentTool(tool)
				editor.keyDown('Shift')
				editor.keyDown('Meta')

				editor.pointerDown(99, 99)

				// Should be drawing (straight-line mode), not erasing.
				editor.expectToBeIn(`${tool}.drawing`)
			})
		})
	}

	it('explicit eraser (not from accel) does not get masked or auto-return on key up', () => {
		editor.setCurrentTool('eraser')
		expect(editor.getCurrentToolId()).toBe('eraser')

		editor.keyDown('Meta')
		editor.keyUp('Meta')

		// Still eraser; no transient return because there's no onInteractionEnd.
		expect(editor.getCurrentToolId()).toBe('eraser')
		expect(editor.getCurrentTool().id).toBe('eraser')
	})
})