package widget

import "fmt"
import . "gitlab.com/beoran/ebsgo/zori/types"
import "gitlab.com/beoran/ebsgo/zori/backend"
import "gitlab.com/beoran/ebsgo/zori/state"
import  "gitlab.com/beoran/ebsgo/zori/style"
import "gitlab.com/beoran/ebsgo/zori/event"
import "gitlab.com/beoran/ebsgo/monolog"

var LastID = 0

type ActionCallback func (w Widget, data ... interface{}) event.Result

type Basic struct {
    Be          backend.Backend
    ID          int
    MyRoot      RootWidget
    Box
    Outer       Box
    Inner       Box
    Z           int
    style.BasicTheme
    MyParent    Widget
    MyChildren []Widget
    state.Flag
    Result      interface{}
    ActionCallback        
}

func (b * Basic) SetBounds(bounds * Box) {
    b.Box.X   = bounds.X
    b.Box.Y   = bounds.Y
    b.Box.W   = bounds.W
    b.Box.H   = bounds.H
    b.Outer   = b.Box
    b.Inner   = b.Box
}


func NewBasicWithTheme(parent Widget, bounds * Box, theme * style.Theme, cb ActionCallback) * Basic {
    b := &Basic{}
    
    LastID++
    b.ID = LastID
    
    if parent != nil {
        b.Be        = parent.Backend()
        if parent.Theme() != nil {
            b.MyTheme   = * parent.Theme()
        }
        
        if root, ok := parent.(RootWidget) ; ok {
            b.MyRoot = root
        } else {
            b.MyRoot    = parent.Root()
        }
        
        b.MyParent  = parent
        box := Bounds(parent.Top(), parent.Left(), parent.Width(), parent.Height())
        b.SetBounds(&box)
    }
    
    if bounds != nil {
        b.SetBounds(bounds)
    }   
    
    if theme != nil {
        b.MyTheme = *theme
    }
    
    if cb != nil {
        b.ActionCallback = cb
    }

    return b;
}

func NewBasic(parent Widget, bounds * Box, cb ActionCallback) * Basic {
    return NewBasicWithTheme(parent, bounds, nil, cb)
}

func NewBasicWidgetWithTheme(parent Widget, bounds * Box, theme * style.Theme, cb ActionCallback) Widget {
    return Widget(NewBasicWidgetWithTheme(parent, bounds, theme, cb));
}

func NewBasicWidget(parent Widget, bounds * Box, cb ActionCallback) Widget {
    return Widget(NewBasicWidget(parent, bounds, cb));
}

func (b Basic) Backend() backend.Backend {
    return b.Be
}

func (b Basic) Parent() Widget {
    return b.MyParent
}

func (b Basic) Root() RootWidget {
    return b.MyRoot
}

func (b Basic) Children() []Widget {
    return b.MyChildren
}


func (b * Basic) AddChild(widget Widget) Widget {
    b.MyChildren = append(b.MyChildren, widget)
    return widget
}

func (bw *Basic) Action(ev event.Action) event.Result { 
    monolog.Info("Action"); 
    if bw.ActionCallback != nil {
        return bw.ActionCallback(bw, ev.Data)
    }
    return event.Pass; 
}

                                                                       
func (bw *Basic) Update(ev event.Update) event.Result                   { monolog.Info("Update"); return event.Pass; }
func (bw *Basic) Draw(ev event.Draw) event.Result                       { monolog.Info("Draw"); return event.Pass; }
func (bw *Basic) Resize(ev event.Resize) event.Result                   { monolog.Info("Resize"); return event.Pass; }
func (bw *Basic) Destroy(ev event.Destroy) event.Result                 { monolog.Info("Destroy"); return event.Pass; }
func (bw *Basic) Close(ev event.Close) event.Result                     { monolog.Info("Close"); return event.Pass; }
func (bw *Basic) NewChild(ev event.NewChild) event.Result               { monolog.Info("Child"); return event.Pass; }
func (bw *Basic) JoystickButtonPress(ev event.Joystick) event.Result    { monolog.Info("JBP"); return event.Pass; }
func (bw *Basic) JoystickButtonRelease(ev event.Joystick) event.Result  { monolog.Info("JBR"); return event.Pass; }
func (bw *Basic) JoystickAxis(ev event.Joystick) event.Result           { monolog.Info("JAX"); return event.Pass; }
func (bw *Basic) KeyPress(ev event.Key) event.Result                    { monolog.Info("KEP"); return event.Pass; }
func (bw *Basic) KeyRelease(ev event.Key) event.Result                  { monolog.Info("KER"); return event.Pass; }
func (bw *Basic) MouseAxes(ev event.Mouse) event.Result                 { monolog.Info("MAX"); return event.Pass; }
func (bw *Basic) MouseWarped(ev event.Mouse) event.Result               { monolog.Info("MWA"); return event.Pass; }
func (bw *Basic) MouseButtonPress(ev event.Mouse) event.Result          { monolog.Info("MBP"); return event.Pass; }
func (bw *Basic) MouseButtonRelease(ev event.Mouse) event.Result        { monolog.Info("MBR"); return event.Pass; }
func (bw *Basic) MouseEnterDisplay(ev event.Mouse) event.Result         { monolog.Info("MED"); return event.Pass; }
func (bw *Basic) MouseLeaveDisplay(ev event.Mouse) event.Result         { monolog.Info("MLD"); return event.Pass; }
func (bw *Basic) TouchBegin(ev event.Touch) event.Result                { monolog.Info("TB"); return event.Pass; }
func (bw *Basic) TouchEnd(ev event.Touch) event.Result                  { monolog.Info("TE"); return event.Pass; }
func (bw *Basic) TouchMove(ev event.Touch) event.Result                 { monolog.Info("TM"); return event.Pass; }
func (bw *Basic) TouchCancel(ev event.Touch) event.Result               { monolog.Info("TC"); return event.Pass; }

func (bw *Basic) Default(ev event.Event) event.Result { 
    monolog.Warning("Warning using default event handler for type %d %s!", ev.Type(), event.String(ev));
    return event.Pass;
}

func (bw *Basic) KeyChar(kc event.Key) event.Result {
    monolog.Info("KeyChar of Basic")
    return event.Done
}

// Checks if the coordinates are inside the main rectange of the widget.
func (bw *Basic) IsInside(x, y int) bool {
    return (x >= bw.X) && (x <= bw.X + bw.W) && (y >= bw.Y) && (y <= (bw.Y + bw.H))
}

func (bw * Basic) String() string {
    return fmt.Sprintf("widget %d", bw.ID)
}

func DispatchRecursive(bw Widget, ev event.Event) event.Result {
    res := event.Dispatch(ev, bw)
    dlev := "INFO"
    switch ev.(type) { 
        case event.Draw: dlev = "DEBUG"
        case event.Update: dlev = "DEBUG"
        case event.Mouse: if ev.Type() == event.TypeMouseAxes { dlev = "DEBUG" ; }
        default: break
    }
    monolog.Log(dlev, "Parent dispatch: %s -> %s", event.String(ev), bw.String())

    if event.Done != res {
        one_ok := false
        for _ , child := range bw.Children() {
            monolog.Log(dlev, "Child dispatch: %v -> %s", child, event.String(ev))
            res := event.Dispatch(ev, child)
            if res == event.Done {
                one_ok = true
            }
        }
        if one_ok {
            return event.Done
        } else {
            return event.Pass
        }        
    } else {
        return event.Done
    }
}

func (bw * Basic) Dispatch(ev event.Event) event.Result {
    return DispatchRecursive(bw, ev)
}


/** Returns whether or not a widget will even handle an event in the first place.
 * For example, a hidden widget won't draw, and a disabled widget won't 
 * accept any system events, and a NULL widget doesn't accept events at all.. */
func (bw * Basic) AcceptsEvent(ev event.Event) bool {
    switch ev.(type) {
        case event.Draw: return bw.Visible()
        default: return bw.Active()
    }
}

func (bw * Basic) Priority() int {
    return bw.Z
}

func (bw * Basic) Compare(w Widget) int {
    return (w.Priority() - bw.Priority())
}



/* Gets the theme to use for a marked widget. Looks up a root widget and then 
 * looks for the cursor to determine this. */
func (bw * Basic) MarkedTheme() style.Theme {
    return bw.Root().MarkedTheme()
}

/* Gets the style to use for a hovered widget. Looks up a screen widget and then 
 * looks for the cursor t determine this. */
func (bw * Basic) HoveredTheme() style.Theme {
    return bw.Root().HoveredTheme()
}


/* Sets the widget's margins */
func (bw * Basic) SetMargins(left, top, right, bottom int) * Basic {
    bw.Outer = bw.Box
    bw.Outer.X -=  left
    bw.Outer.Y -=  top
    bw.Outer.W +=  (left+ right)
    bw.Outer.H +=  (top + bottom)
    return bw
}

/* Sets the widget's margins, all equal */
func (bw * Basic) SetMargin(size int) * Basic {
    return bw.SetMargins(size, size,  size,  size)
}

/* Sets the widget's paddins */
func (bw * Basic) SetPaddings(left, top, right, bottom int) * Basic {
    bw.Inner   = bw.Box
    bw.Inner.X +=  left
    bw.Inner.Y +=  top
    bw.Inner.W -=  (left+ right)
    bw.Inner.H -=  (top + bottom)
    return bw
}

/* Sets the widget's paddings, all equal */
func (bw * Basic) SetPadding(size int) * Basic {
    return bw.SetPaddings(size, size,  size,  size)
}


/* Draws a widget's frame based on it's style. If the background bitmap is set 
 * then that is used, otherwise,  the background color is used, including a border
 * if needed. */
func (bw * Basic) DrawBackground() { 
    be := bw.Backend()
    dx := bw.X
    dy := bw.Y
    dw := bw.W
    dh := bw.H
    
    theme := bw.MyTheme
        
    if bw.Hovered() {
        theme = bw.HoveredTheme()
    } else if bw.Marked() {
        theme = bw.MarkedTheme()
    }
    
    if theme.Background.Bitmap != nil {
        bmp := theme.Background.Bitmap
        sw  := bmp.Width()
        sh  := bmp.Height()
        // XXX should use draw9 algorithm here
        be.DrawScaledBitmap(0,0,sw,sh,dx,dy,dw,dh, bmp)
    } else { 
        fillcol := theme.Background.Color
        bordcol := theme.Border.Color
        thick   := theme.Border.Size
        rad     := theme.Border.Radius
        be.DrawRoundedSlab(dx, dy, dw, dh, rad, rad, fillcol)
        be.DrawRoundedRectangle(dx, dy, dw, dh, rad, rad, bordcol, thick)
    }
}

func (bw * Basic) SetState(flag state.Flag, set bool) bool {
    if set {
        bw.Flag |= flag        
    } else {
        bw.Flag &= (^flag)
    }
    return bw.IsState(flag)
}

func (bw * Basic) IsState(flag state.Flag) bool { 
    return ((bw.Flag & flag) == flag)
}

func (bw * Basic) Visible() bool {
    return bw != nil && ((bw.Flag & state.HIDDEN) != state.HIDDEN)
}

func (bw * Basic) Active() bool {
    return bw != nil && ((bw.Flag & state.DISABLED) != state.DISABLED )
}

func (bw * Basic) Hovered() bool {
    return bw != nil && bw.IsState(state.HOVERED)
}

func (bw * Basic) Marked() bool {
    return bw != nil && bw.IsState(state.MARKED)
}

func (bw * Basic) SetHovered(set bool) bool {
   return bw.SetState(state.HOVERED, set)
}

func (bw * Basic) SetMarked(set bool) bool {
    return bw.SetState(state.MARKED, set)
}

func (bw * Basic) SetActive(set bool) bool {
    bw.SetState(state.DISABLED, !set)
    return bw.Active()
}

func (bw * Basic) SetVisible(set bool) bool {
    bw.SetState(state.HIDDEN, !set)
    return bw.Visible()
}

/** Get active and visible */
func (bw * Basic) Live() bool {
    return bw.Active() && bw.Visible()
}

/** Set active and visible */
func (bw * Basic) SetLive(live bool) {
    bw.SetActive(live)
    bw.SetVisible(live)
}


func (bw * Basic) FindParent(predicate func (wi Widget) bool) Widget {    
    for parent := bw.Parent() ; parent != nil ; parent = parent.Parent() {
        if predicate(parent) {
            return parent
        }
    }
    return nil    
}

func (bw * Basic) Mark() event.Result {
    root := bw.Root().(*Root)
    root.Cursors.Keyjoy.Point = bw.Box.Point
    return event.Done
}

/* Moves the widget by the offset (dx, dy). Does not move it's children.  */
func (bw * Basic) MoveSelfBy(dx, dy int) {
    bw.Box.X += dx
    bw.Box.Y += dy
    bw.Inner.X += dx
    bw.Inner.Y += dy
    bw.Outer.X += dx
    bw.Outer.Y += dy
}


/* Resizes the widget by the offset (dw, dh). Does not move it's children.  */
func (bw * Basic) ResizeSelfBy(dw, dh int) {
    bw.Box.W += dw
    bw.Box.H += dh
    bw.Inner.W += dw
    bw.Inner.H += dh
    bw.Outer.W += dw
    bw.Outer.H += dh
}


/* Moves the widget by the offset (dx, dy). It's children will be moved as well recursively
 * keeping the offset */
func (bw * Basic) MoveBy(dx, dy int) {
    bw.MoveSelfBy(dx, dy)
    for _, child := range bw.MyChildren {
        child.MoveBy(dx, dy)
    }
}


/* Moves the widget to (x, y). It's children will be moved as well recursively
 * keeping the offset */
func (bw * Basic) MoveTo(x, y int) {
    dx := bw.Box.X - x
    dy := bw.Box.Y - y
    bw.MoveBy(dx, dy)
}

/* Moves the widget to (x, y). Doesn't move children. */
func (bw * Basic) MoveSelfTo(x, y int) {
    dx := bw.Box.X - x
    dy := bw.Box.Y - y
    bw.MoveSelfBy(dx, dy)
}

/* Resizes the widget to (w, h). Doesn't resize children. Margins and padding will be 
 * resized accordingly. */
func (bw * Basic) ResizeSelfTo(w, h int) {
    dx := bw.Box.W - w
    dy := bw.Box.H - h
    bw.ResizeSelfBy(dx, dy)
}
 

    
/* Makes the widget fit itself to all direct children.
 * Does not resize nor move the children.
 */
func (bw * Basic) FitToChildren(w, h int) {
    min_x := 640
    min_y := 480
    min_w := 0
    min_h := 0
    be    := bw.Backend()
    
    if be.Display() != nil {
        min_x = be.Display().Width()  
        min_y = be.Display().Height()          
    }
    

    for _,child := range bw.MyChildren {
        if child.Left() < min_x {
            min_x = child.Left()
        }        
        if child.Top() < min_y {
            min_y = child.Top()
        }
        if child.Width() > min_w {
            min_w = child.Width()
        }
        if child.Height() > min_h {
            min_w = child.Height()
        }
    }
    
    bw.MoveSelfTo(min_x, min_y)
    bw.ResizeSelfTo(min_w, min_h)
}


/* Style getters for ease of use. */
func (bw * Basic) TextFont() Font {
    theme := bw.MyTheme
    if (theme.Text.Font != nil) { 
        return theme.Text.Font
    } 
    
    if bw.MyParent != nil {
        return bw.Root().Theme().Text.Font
    }
    return nil
}

func (bw * Basic) TextColor() Color {
    theme := bw.MyTheme
    return theme.Text.Color
}

func (bw * Basic) BackgroundColor() Color {
    theme := bw.MyTheme
    return theme.Background.Color
}