package ui

import (
	"strings"
	"time"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/widget"

	"viewsagent/internal/capture"
	"viewsagent/internal/win32"
)

// cardTitle 是答案浮窗的标题，win32 靠它找 HWND。
const cardTitle = "viewsagent-card"

// floatCard 是贴在选区旁边的置顶小窗，只显示最新答案。
type floatCard struct {
	win     fyne.Window
	body    *widget.RichText
	region  capture.Region
	visible bool
}

func newFloatCard(a fyne.App) *floatCard {
	c := &floatCard{win: a.NewWindow(cardTitle)}
	rt := widget.NewRichText()
	rt.Wrapping = fyne.TextWrapWord
	c.body = rt

	c.win.SetContent(container.NewBorder(
		nil, nil, nil, nil,
		container.NewPadded(rt),
	))
	c.win.Resize(fyne.NewSize(400, 240))
	return c
}

// setRegion 记录当前监视区域，用于定位浮窗。
func (c *floatCard) setRegion(r capture.Region) {
	c.region = r
}

// update 刷新浮窗内容。
func (c *floatCard) update(text string) {
	text = strings.TrimSpace(text)
	if text == "" {
		text = "（空）"
	}
	c.body.ParseMarkdown(text)
	if c.visible {
		c.place()
	}
}

// show 显示浮窗。
func (c *floatCard) show() {
	if c.visible {
		c.place()
		c.win.RequestFocus()
		return
	}
	c.visible = true
	c.win.Show()
	go func() {
		time.Sleep(120 * time.Millisecond)
		fyne.Do(c.place)
	}()
}

// hide 隐藏浮窗。
func (c *floatCard) hide() {
	c.visible = false
	c.win.Hide()
}

// toggle 切换显示状态。
func (c *floatCard) toggle() {
	if c.visible {
		c.hide()
		return
	}
	c.show()
}

// visibleNow 返回是否正在显示。
func (c *floatCard) visibleNow() bool { return c.visible }

// place 把浮窗贴到选区下方（放不下就贴上方），并置顶。
func (c *floatCard) place() {
	hwnd, err := win32.FindWindowByTitle(cardTitle)
	if err != nil {
		return
	}
	_ = win32.SetTopMost(hwnd)

	rect, err := win32.WindowRect(hwnd)
	if err != nil || rect.Width() <= 0 || rect.Height() <= 0 {
		return
	}
	if !c.region.Valid() {
		return
	}
	mon, _ := win32.MonitorAt(c.region.X+c.region.W/2, c.region.Y+c.region.H/2)
	work := mon.Work
	if work.Width() <= 0 {
		work = mon.Rect
	}
	gap := int(8 * max(mon.Scale, 1))

	x := c.region.X
	y := c.region.Y + c.region.H + gap
	if y+rect.Height() > work.Bottom {
		y = c.region.Y - rect.Height() - gap
	}
	if y < work.Top {
		y = work.Bottom - rect.Height()
	}
	if x+rect.Width() > work.Right {
		x = work.Right - rect.Width()
	}
	if x < work.Left {
		x = work.Left
	}
	_ = win32.MoveTo(hwnd, win32.Rect{Left: x, Top: y, Right: x + rect.Width(), Bottom: y + rect.Height()})
}