package ui

import (
	"time"

	"opslag.de/schobers/galleg/allegro5"
	"opslag.de/schobers/geom"
)

type Container interface {
	Control
	Children() []Control
	Arrange(Context, geom.RectangleF)
}

func NewContainer(parent Container, children ...Control) *ContainerBase {
	return &ContainerBase{ControlBase{}, false, parent, children}
}

type ContainerBase struct {
	ControlBase
	created  bool
	parent   Container
	children []Control
}

func (c *ContainerBase) Children() []Control {
	return c.children
}

func (c *ContainerBase) Arrange(ctx Context, rect geom.RectangleF) {
	c.ControlBase.SetRect(rect)
	for _, child := range c.children {
		Arrange(ctx, child, rect)
	}
}

func (c *ContainerBase) Append(child Control) {
	if c.created {
		panic("error append, must use append create when control is already created")
	}
	c.children = append(c.children, child)
}

func (c *ContainerBase) AppendCreate(ctx Context, child Control) error {
	if !c.created {
		panic("error append create, must use append when control is not yet created")
	}
	c.children = append(c.children, child)
	return child.Created(ctx, c)
}

func (c *ContainerBase) RemoveFn(ctx Context, pred func(Control) bool) {
	var i = 0
	for i < len(c.children) {
		if pred(c.children[i]) {
			c.children[i].Destroyed(ctx)
			c.children = c.children[:i+copy(c.children[i:], c.children[i+1:])]
		} else {
			i++
		}
	}
}

func (c *ContainerBase) Created(ctx Context, p Container) error {
	if c.created {
		panic("already created")
	}
	c.parent = p
	for _, child := range c.children {
		err := child.Created(ctx, p)
		if nil != err {
			return err
		}
	}
	c.created = true
	return nil
}

func (c *ContainerBase) Destroyed(ctx Context) {
	if !c.created {
		panic("not yet created or already destroyed")
	}
	for _, child := range c.children {
		child.Destroyed(ctx)
	}
}

func (c *ContainerBase) Update(ctx Context, dt time.Duration) {
	for _, child := range c.children {
		child.Update(ctx, dt)
	}
}

func (c *ContainerBase) Handle(ctx Context, ev allegro5.Event) {
	for _, child := range c.children {
		child.Handle(ctx, ev)
	}
}

func (c *ContainerBase) Render(ctx Context) {
	for _, child := range c.children {
		child.Render(ctx)
	}
	c.ControlBase.Render(ctx)
}