/**
 * Designer 编辑器测试（对应设计文档 §4.5）。
 *
 * 核心断言：
 * - 编辑器状态（选中、缩放、平移）独立于文档（§3.2）。
 * - 所有编辑操作通过命令，可撤销可重做。
 * - 坐标转换在屏幕 px 与文档 mm 之间正确换算。
 */
import { describe, expect, it, vi } from "vitest"
import { createDocument, createElementId, type ReportDocument } from "@report/core"
import { EditorSession, createEditorSession } from "../src/editor.js"
import { screenToDoc, docToScreen, hitTest, clampZoom, snapToGrid } from "../src/coords.js"
import { createDesignerState } from "../src/state.js"
import { createTextElement, createRectElement } from "../src/commands.js"

function sampleDoc(): ReportDocument {
  const doc = createDocument({ name: "编辑器测试" })
  const detail = doc.sections.find((s) => s.kind === "detail")!
  detail.children.push(
    createTextElement({ x: 0, y: 0, width: 50, height: 8 }, "标题"),
    createRectElement({ x: 0, y: 10, width: 50, height: 20 }),
  )
  return doc
}

describe("编辑器状态独立于文档", () => {
  it("选中状态不写入文档", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = doc.sections.find((s) => s.kind === "detail")!
    const firstId = detail.children[0]!.id

    editor.select(firstId)
    // 文档序列化后不应包含任何选中状态
    const serialized = JSON.stringify(editor.getDocument())
    expect(serialized).not.toContain("selectedIds")
    expect(editor.getSelectedIds()).toEqual([firstId])
  })

  it("缩放与平移不写入文档", () => {
    const editor = new EditorSession(sampleDoc())
    editor.setZoom(1.5)
    editor.pan(10, 20)
    const state = editor.getState()
    expect(state.zoom).toBe(1.5)
    expect(state.panX).toBe(10)
    expect(state.panY).toBe(20)
    // 文档本身不含这些字段
    expect(JSON.stringify(editor.getDocument())).not.toContain("zoom")
  })
})

describe("选择", () => {
  it("选择单个元素", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = doc.sections.find((s) => s.kind === "detail")!
    const id = detail.children[0]!.id
    editor.select(id)
    expect(editor.getSelectedIds()).toEqual([id])
  })

  it("多选与清空", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = doc.sections.find((s) => s.kind === "detail")!
    const ids = detail.children.map((c) => c.id)
    editor.selectMany(ids)
    expect(editor.getSelectedIds().length).toBe(2)
    editor.clearSelection()
    expect(editor.getSelectedIds()).toHaveLength(0)
  })
})

describe("编辑命令与撤销重做", () => {
  it("移动元素可撤销", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = doc.sections.find((s) => s.kind === "detail")!
    const id = detail.children[0]!.id
    const before = { ...detail.children[0]!.frame }

    editor.select(id)
    editor.moveElements({ [id]: { x: 100, y: 100, width: 50, height: 8 } })

    const afterMove = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!.frame
    expect(afterMove.x).toBe(100)

    editor.undo()
    const afterUndo = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!.frame
    expect(afterUndo.x).toBe(before.x)

    editor.redo()
    const afterRedo = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!.frame
    expect(afterRedo.x).toBe(100)
  })

  it("新增元素可撤销", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const beforeCount = detail.children.length

    const newEl = createTextElement({ x: 0, y: 0, width: 30, height: 8 }, "新元素")
    editor.addElement(detail.id, newEl)

    const afterAdd = editor.getDocument().sections.find((s) => s.kind === "detail")!.children.length
    expect(afterAdd).toBe(beforeCount + 1)

    editor.undo()
    const afterUndo = editor.getDocument().sections.find((s) => s.kind === "detail")!.children.length
    expect(afterUndo).toBe(beforeCount)
  })

  it("删除选中元素", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const beforeCount = detail.children.length
    const id = detail.children[0]!.id

    editor.select(id)
    editor.deleteSelected()

    const afterDelete = editor.getDocument().sections.find((s) => s.kind === "detail")!.children.length
    expect(afterDelete).toBe(beforeCount - 1)
    expect(editor.getSelectedIds()).toHaveLength(0)
  })

  it("修改元素属性", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const id = detail.children[0]!.id

    editor.updateElement(id, "props.text", "改后的标题")
    const after = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!
    expect((after.props as { text: string }).text).toBe("改后的标题")
  })
})

describe("坐标转换", () => {
  it("屏幕 px 与文档 mm 换算（zoom=1, pan=0）", () => {
    const state = createDesignerState()
    const doc = screenToDoc({ x: 96, y: 96 }, state)
    // 96px = 1in = 25.4mm
    expect(doc.x).toBeCloseTo(25.4, 2)
    expect(doc.y).toBeCloseTo(25.4, 2)

    const screen = docToScreen({ x: 25.4, y: 25.4 }, state)
    expect(screen.x).toBeCloseTo(96, 2)
    expect(screen.y).toBeCloseTo(96, 2)
  })

  it("缩放影响换算", () => {
    const state = createDesignerState({ zoom: 2 })
    const doc = screenToDoc({ x: 96, y: 0 }, state)
    // 96px / 2 = 48px = 12.7mm
    expect(doc.x).toBeCloseTo(12.7, 2)
  })

  it("命中测试", () => {
    const state = createDesignerState()
    const frame = { x: 0, y: 0, width: 25.4, height: 25.4 }
    // 中心点 (48,48)px = 12.7mm 在 frame 内
    expect(hitTest({ x: 48, y: 48 }, frame, state)).toBe(true)
    // 外部点不在
    expect(hitTest({ x: 200, y: 200 }, frame, state)).toBe(false)
  })

  it("缩放钳制在 [0.5, 2]", () => {
    expect(clampZoom(0.1)).toBe(0.5)
    expect(clampZoom(5)).toBe(2)
    expect(clampZoom(1)).toBe(1)
  })
})

describe("拖拽", () => {
  it("拖拽移动选中元素", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const id = detail.children[0]!.id
    const before = { ...detail.children[0]!.frame }

    editor.select(id)
    editor.beginDrag(0, 0)
    editor.updateDrag(10, 20)
    editor.endDrag()

    const after = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!.frame
    expect(after.x).toBe(before.x + 10)
    expect(after.y).toBe(before.y + 20)
    expect(editor.isDragging()).toBe(false)
  })

  it("吸附作用在结果坐标上，拖动落点为整数 mm", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const id = detail.children[0]!.id

    editor.select(id)
    editor.beginDrag(0, 0)
    editor.updateDrag(10.4, 20.6)
    editor.endDrag()

    const after = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!.frame
    // 起点 x=0 y=0，位移取整后应为 10 / 21
    expect(after.x).toBe(10)
    expect(after.y).toBe(21)
  })

  it("吸附取整的是落点而非位移量", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const id = detail.children[1]!.id

    // 关键：起点必须是非整数，否则「取整落点」与「取整位移量」结果相同，
    // 这个用例就区分不出两种实现。
    editor.moveElements({ [id]: { x: 5.4, y: 10.4, width: 50, height: 20 } })

    editor.select(id)
    editor.beginDrag(0, 0)
    editor.updateDrag(0.3, 0.3)
    editor.endDrag()

    const after = editor.getDocument().sections.find((s) => s.kind === "detail")!.children[1]!.frame
    // 落点 5.7 → 6、10.7 → 11。
    // 若改成对位移量取整，结果会是 5.4 和 10.4（位移 0.3 取整为 0），与期望不符。
    expect(after.x).toBe(6)
    expect(after.y).toBe(11)
  })
})

describe("拖拽的事务语义", () => {
  it("拖拽中途停顿超过时间窗，仍然只产生一步撤销", () => {
    vi.useFakeTimers()
    vi.setSystemTime(new Date("2026-01-01T00:00:00Z"))
    try {
      const doc = sampleDoc()
      const editor = new EditorSession(doc)
      const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
      const id = detail.children[0]!.id
      const frame = () =>
        editor.getDocument().sections.find((s) => s.kind === "detail")!.children[0]!.frame

      editor.select(id)
      editor.beginDrag(0, 0)
      editor.updateDrag(10, 10)

      // 模拟用户拖到一半停手，闲置远超 History 的 500ms 合并窗口后继续拖。
      // 若靠 mergeKey 时间窗合并，这里会被拆成两条撤销记录。
      vi.setSystemTime(new Date("2026-01-01T00:00:10Z"))
      editor.updateDrag(30, 30)
      editor.endDrag()

      expect(frame().x).toBe(30)

      // 关键：一次撤销直接回到原位，而不是停在中间态 10
      editor.undo()
      expect(frame().x).toBe(0)
    } finally {
      vi.useRealTimers()
    }
  })

  it("拖拽没有产生位移时不写入撤销记录", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const id = detail.children[0]!.id

    editor.select(id)
    editor.beginDrag(0, 0)
    editor.endDrag()

    expect(editor.canUndo()).toBe(false)
  })
})

describe("吸附开关（snapToGrid）", () => {
  it("开启时取整到整数 mm", () => {
    const state = createDesignerState({ snapEnabled: true })
    expect(snapToGrid(10.4, state)).toBe(10)
    expect(snapToGrid(10.6, state)).toBe(11)
  })

  it("关闭时原样返回", () => {
    const state = createDesignerState({ snapEnabled: false })
    expect(snapToGrid(10.4, state)).toBe(10.4)
    expect(snapToGrid(-3.7, state)).toBe(-3.7)
  })
})

describe("多选切换与剪贴板", () => {
  it("toggleSelect 在选中与取消之间切换", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const first = detail.children[0]!.id
    const second = detail.children[1]!.id

    editor.toggleSelect(first)
    expect(editor.getSelectedIds()).toEqual([first])

    // 再切一次同一个 → 取消选中
    editor.toggleSelect(first)
    expect(editor.getSelectedIds()).toHaveLength(0)

    // 两个都切上 → 多选
    editor.toggleSelect(first)
    editor.toggleSelect(second)
    expect(editor.getSelectedIds().sort()).toEqual([first, second].sort())
  })

  it("粘贴后选中新元素，而不是清空选中", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const sourceId = detail.children[0]!.id
    const beforeCount = detail.children.length

    editor.select(sourceId)
    editor.copy()
    editor.paste(detail.id)

    const afterChildren = editor.getDocument().sections.find((s) => s.kind === "detail")!.children
    expect(afterChildren.length).toBe(beforeCount + 1)

    // 回归：旧实现这里会把选中清空
    const selectedIds = editor.getSelectedIds()
    expect(selectedIds).toHaveLength(1)
    expect(selectedIds[0]).not.toBe(sourceId)
    // 选中的确实是刚粘贴出来的那个
    expect(afterChildren.some((c) => c.id === selectedIds[0])).toBe(true)
  })

  it("粘贴的元素相对源元素偏移 5mm 避免重叠", () => {
    const doc = sampleDoc()
    const editor = new EditorSession(doc)
    const detail = editor.getDocument().sections.find((s) => s.kind === "detail")!
    const source = detail.children[0]!

    editor.select(source.id)
    editor.copy()
    editor.paste(detail.id)

    const pasted = editor.getDocument().sections
      .find((s) => s.kind === "detail")!
      .children.find((c) => c.id === editor.getSelectedIds()[0])!
    expect(pasted.frame.x).toBe(source.frame.x + 5)
    expect(pasted.frame.y).toBe(source.frame.y + 5)
  })
})