package gallery

import (
	"fmt"
	"strings"

	"github.com/egoist/mygo/ui"

	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/icon"
	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/input"
	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/layout"
	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
)

const logo = "8BIT·MYGO·UI"

func (a *App) topBar(c *ui.Context) {
	k := pixel.K(c)
	ui.Row(c).Height(k.D(24)).Padding(0, k.D(6)).Gap(k.D(8)).Draw(func(p *ui.Painter, r ui.Rect) {
		g := k.Canvas(p, r)
		g.Rect(0, 0, g.W, g.H, pixel.Face)
		g.HLine(0, g.H-2, g.W, pixel.Shade)
		g.HLine(0, g.H-1, g.W, pixel.Edge)
	}).Children(func() {
		if press(c, pixel.Measure(logo)+2, 18, "home", func(g pixel.Canvas, st pixel.State) {
			ink := pixel.Accent
			if st.Hover {
				ink = pixel.AccentLit
			}
			shadow(g, 0, 1, logo, ink, 1)
		}) {
			a.Go("/")
		}
		a.search = input.SearchField(c, "Search components", &a.query, input.SearchFieldOptions{Placeholder: "/ search 搜索", Width: 150})
		if m := matches(a.query); a.search.Submitted && len(m) > 0 {
			a.Go(m[0].Path())
		}
		ui.Spacer(c)
		a.paletteControl(c)
		other, mark := pixel.Zh, "中"
		if a.locale == pixel.Zh {
			other, mark = pixel.En, "EN"
		}
		if input.Button(c, mark, input.ButtonOptions{Size: input.Small, Label: "language"}).Clicked {
			a.locale = other
		}
	})
}

func (a *App) paletteControl(c *ui.Context) {
	pal := pixel.Palettes[a.palette]
	arrows := input.IconButtonOptions{Variant: input.Ghost, Size: input.Small}
	if input.IconButton(c, icon.ChevronLeft, "previous palette", arrows).Clicked {
		a.setPalette(a.palette - 1)
	}
	name := strings.ToUpper(pal.Name) + " " + pal.Zh
	press(c, 4*pixel.Slots+6+pixel.Measure(name), 16, "palette "+pal.Name, func(g pixel.Canvas, st pixel.State) {
		g.Rect(0, 2, 4*pixel.Slots+2, 12, pixel.Edge)
		for i := range pixel.Slots {
			g.Rect(1+i*4, 3, 4, 10, pixel.Slot(i))
		}
		g.Text(4*pixel.Slots+6, 0, name, pixel.Ink, 1)
	})
	if input.IconButton(c, icon.ChevronRight, "next palette", arrows).Clicked {
		a.setPalette(a.palette + 1)
	}
}

func (a *App) sidebar(c *ui.Context) {
	k := pixel.K(c)
	here := a.router.Path()
	ui.Scroll(c).Width(k.D(120)).Draw(func(p *ui.Painter, r ui.Rect) {
		g := k.Canvas(p, r)
		g.Rect(0, 0, g.W, g.H, pixel.Face)
		g.VLine(g.W-2, 0, g.H, pixel.Shade)
		g.VLine(g.W-1, 0, g.H, pixel.Edge)
	}).Children(func() {
		ui.Column(c).Padding(k.D(4)).Gap(k.D(1)).FocusGroup(ui.Vertical).Children(func() {
			for _, cat := range Categories {
				n := count(cat.Key)
				path := "/cat/" + cat.Key
				on := here == path
				if press(c, 0, 16, cat.Name, func(g pixel.Canvas, st pixel.State) {
					ink := pixel.Ink
					if on {
						g.Rect(0, 0, g.W, g.H, pixel.Accent)
						ink = pixel.AccentInk
					} else if st.Hover {
						g.Rect(0, 0, g.W, g.H, pixel.Lit)
					}
					if n == 0 {
						ink = pixel.Faint
					}
					g.Sprite(2, 2, cat.Icon, 0, ink, 1)
					g.Text(17, 0, cat.Name, ink, 1)
					num := fmt.Sprint(n)
					g.Micro(g.W-pixel.MicroWidth(num)-3, 6, num, ink, 1)
				}) {
					a.Go(path)
				}
			}
		})
	})
}

func (a *App) statusBar(c *ui.Context) {
	layout.StatusBar(c, []string{"/ search · P palette · [ ] prev next", fmt.Sprintf("%d entries", len(Entries()))}, layout.StatusBarOptions{})
}

// press is a custom-drawn chrome tile; true when clicked.
func press(c *ui.Context, w, h int, name string, draw func(g pixel.Canvas, st pixel.State)) bool {
	k := pixel.K(c)
	shell, base, st := pixel.Shell(c, func() *ui.Element { return ui.ButtonBase(c).Label(name) })
	if w > 0 {
		shell.Width(k.D(w))
	}
	shell.Height(k.D(h)).Draw(func(p *ui.Painter, r ui.Rect) {
		g := k.Canvas(p, r)
		draw(g, st)
		if st.Focus {
			g.FocusMark(0, 0, g.W, g.H)
		}
	})
	return base.Clicked()
}

// shadow draws s with a shadow one scaled dot down-right.
func shadow(g pixel.Canvas, x, y int, s string, ink pixel.Slot, scale int) {
	g.Text(x+scale, y+scale, s, pixel.Shade, scale)
	g.Text(x, y, s, ink, scale)
}

func count(cat string) int {
	n := 0
	for _, e := range Entries() {
		if e.Category == cat {
			n++
		}
	}
	return n
}