package doodle

import (
	"git.kirsle.net/apps/doodle/pkg/balance"
	"git.kirsle.net/apps/doodle/pkg/doodads"
	"git.kirsle.net/apps/doodle/pkg/uix"
	"git.kirsle.net/go/render"
	"git.kirsle.net/go/ui"
)

// setupInventoryHud configures the Inventory HUD.
func (s *PlayScene) setupInventoryHud() {
	s.invenFrame = ui.NewFrame("Inventory")
	s.invenDoodads = map[string]*uix.Canvas{}
	s.invenFrame.Configure(ui.Config{
		BorderStyle: ui.BorderRaised,
		BorderSize:  2,
		Background:  render.RGBA(128, 128, 128, 60),
	})

	// Items label.
	label := ui.NewLabel(ui.Label{
		Text: "Items:",
		Font: balance.LabelFont,
	})
	label.Compute(s.d.Engine)

	// Configure the label tall enough to cover typical 32x32 item doodads.
	// This pushes the Frame height tall enough.
	label.Configure(ui.Config{
		Height: 36,
		Width:  label.Size().W + 2,
	})
	s.invenFrame.Pack(label, ui.Pack{
		Side: ui.W,
		PadX: 2,
		PadY: 4,
	})

	// Add the inventory frame to the screen frame.
	s.screen.Place(s.invenFrame, ui.Place{
		Top:   40,
		Right: 40,
	})

	// Hide inventory if empty.
	if len(s.invenItems) == 0 {
		s.invenFrame.Hide()
	}
}

// computeInventory adjusts the inventory HUD when the player's inventory changes.
func (s *PlayScene) computeInventory() {
	items := s.Player.ListItems()
	if len(items) != len(s.invenItems) {
		// Inventory has changed! See which doodads we have
		// and which we need to load.
		var seen = map[string]interface{}{}
		for _, filename := range items {
			seen[filename] = nil

			if _, ok := s.invenDoodads[filename]; !ok {
				// Cache miss. Load the doodad here.
				doodad, err := doodads.LoadFile(filename)
				if err != nil {
					s.d.Flash("Inventory item '%s' error: %s", filename, err)
					continue
				}

				canvas := uix.NewCanvas(doodad.ChunkSize(), false)
				canvas.LoadDoodad(doodad)
				canvas.Resize(render.NewRect(
					doodad.ChunkSize(), doodad.ChunkSize(),
				))
				s.invenFrame.Pack(canvas, ui.Pack{
					Side: ui.W,

					// TODO: work around a weird padding bug. item had too
					// tall a top margin when added to the inventory frame!
					PadX: 8,
				})
				s.invenDoodads[filename] = canvas
			}

			s.invenDoodads[filename].Show()
		}

		// Hide any doodad that used to be in the inventory but now is not.
		for filename, canvas := range s.invenDoodads {
			if _, ok := seen[filename]; !ok {
				canvas.Hide()
			}
		}

		// Recompute the size of the inventory frame.
		// TODO: this works around a bug in ui.Frame, at the bottom of
		// compute_packed, a frame Resize's itself to fit the children but this
		// trips the "manually set size" boolean... packing more items after a
		// computer doesn't resize the frame. So here, we resize-auto it to
		// reset that boolean so the next compute, picks the right size.
		s.invenFrame.Configure(ui.Config{
			AutoResize: true,
			Width:      1,
			Height:     1,
		})
		s.invenFrame.Compute(s.d.Engine)

		// If we removed all items, hide the frame.
		if len(items) == 0 {
			s.invenFrame.Hide()
		} else {
			s.invenFrame.Show()
		}

		// Cache the item list so we don't run the above logic every single tick.
		s.invenItems = items
	}

	// Compute the inventory frame so it positions and wraps the items.
	s.screen.Compute(s.d.Engine)
}