/*
Copyright © Brian Buller <brian@bullercodeworks.com>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
package widgets

import (
	"fmt"
	"time"

	wh "git.bullercodeworks.com/brian/tcell-widgets/helpers"
	"github.com/gdamore/tcell"
)

// ScrollingWidgetList lays out all widgets added one after the other
// It will fill as much space as you give it
type ScrollingWidgetList struct {
	id    string
	style tcell.Style

	orientation ScrollingWidgetListOrient

	x, y    int
	w, h    int
	widgets []Widget

	emptyWidget Widget

	active      bool
	visible     bool
	focusable   bool
	disableTab  bool
	insetBorder bool

	keyMap *KeyMap

	logger func(string, ...any)
}

type ScrollingWidgetListOrient int

const (
	SWLLayV = ScrollingWidgetListOrient(iota)
	SWLLayH
)

var _ Widget = (*ScrollingWidgetList)(nil)

func NewScrollingWidgetList(id string, s tcell.Style) *ScrollingWidgetList {
	ret := &ScrollingWidgetList{}
	ret.Init(id, s)
	return ret
}

func (w *ScrollingWidgetList) Init(id string, s tcell.Style) {
	w.id = id
	w.style = s
	w.visible = true
	w.focusable = true
	w.keyMap = NewKeyMap(NewKey(BuildEK(tcell.KeyTab), func(ev *tcell.EventKey) bool {
		active := w.findActive()
		if active == nil && len(w.widgets) > 0 {
			// No widget is active, but we do have some
			for i := range w.widgets {
				if w.widgets[i].Focusable() {
					w.widgets[i].SetActive(true)
					return true
				}
			}
			return false
		}
		return w.ActivateNext()
	}))
	w.keyMap.Add(NewKey(BuildEK(tcell.KeyBacktab), func(ev *tcell.EventKey) bool {
		active := w.findActive()
		if active == nil && len(w.widgets) > 0 {
			// No widget is active, but we do have some
			for i := len(w.widgets) - 1; i >= 0; i-- {
				if w.widgets[i].Focusable() {
					w.widgets[i].SetActive(true)
					return true
				}
			}
			return false
		}
		return w.ActivatePrev()
	}))
	e := NewText(fmt.Sprintf("%s-empty", w.id), w.style)
	e.SetText("Nothing to Display")
	w.emptyWidget = e
}

func (w *ScrollingWidgetList) Id() string { return w.id }
func (w *ScrollingWidgetList) HandleResize(ev *tcell.EventResize) {
	w.w, w.h = ev.Size()
	w.updateWidgetLayouts()
}

func (w *ScrollingWidgetList) GetKeyMap() *KeyMap   { return w.keyMap }
func (w *ScrollingWidgetList) SetKeyMap(km *KeyMap) { w.keyMap = km }

func (w *ScrollingWidgetList) HandleKey(ev *tcell.EventKey) bool {
	if !w.active || w.disableTab {
		return false
	}
	active := w.findActive()
	if active != nil {
		if active.HandleKey(ev) {
			return true
		}
	}
	return w.keyMap.Handle(ev)
}

func (w *ScrollingWidgetList) GetActiveWidgetIdx() int { return w.findActiveIdx() }
func (w *ScrollingWidgetList) GetActiveWidget() Widget { return w.findActive() }

func (w *ScrollingWidgetList) HandleTime(ev *tcell.EventTime) {
	for _, wi := range w.widgets {
		wi.HandleTime(ev)
	}
}

func (w *ScrollingWidgetList) Draw(screen tcell.Screen) {
	if !w.visible {
		return
	}

	pos := w.GetPos()
	if w.insetBorder {
		wh.Border(pos.X, pos.Y, pos.X+w.w, pos.Y+w.h, wh.BRD_CSIMPLE, w.style, screen)
	}

	for _, wd := range w.widgets {
		pos.DrawOffset(wd, screen)
	}
}

func (w *ScrollingWidgetList) SetStyle(s tcell.Style) { w.style = s }
func (w *ScrollingWidgetList) Active() bool           { return w.active }
func (w *ScrollingWidgetList) SetActive(a bool) {
	w.active = a
	if w.active {
		act := w.findActiveOrFirst()
		if act != nil {
			act.SetActive(true)
		}
	}
}
func (w *ScrollingWidgetList) Visible() bool       { return w.visible }
func (w *ScrollingWidgetList) SetVisible(a bool)   { w.visible = a }
func (w *ScrollingWidgetList) Focusable() bool     { return w.focusable }
func (w *ScrollingWidgetList) SetFocusable(b bool) { w.focusable = b }
func (w *ScrollingWidgetList) SetX(x int)          { w.x = x }
func (w *ScrollingWidgetList) SetY(y int)          { w.y = y }
func (w *ScrollingWidgetList) GetX() int           { return w.x }
func (w *ScrollingWidgetList) GetY() int           { return w.y }
func (w *ScrollingWidgetList) GetPos() Coord       { return Coord{X: w.x, Y: w.y} }
func (w *ScrollingWidgetList) SetPos(c Coord)      { w.x, w.y = c.X, c.Y }
func (w *ScrollingWidgetList) GetW() int           { return w.w }
func (w *ScrollingWidgetList) GetH() int           { return w.h }
func (w *ScrollingWidgetList) SetW(wd int)         { w.w = wd }
func (w *ScrollingWidgetList) SetH(h int)          { w.h = h }
func (w *ScrollingWidgetList) getSize() Coord      { return Coord{X: w.w, Y: w.h} }
func (w *ScrollingWidgetList) SetSize(c Coord)     { w.w, w.h = c.X, c.Y }
func (w *ScrollingWidgetList) WantW() int {
	var wantW int
	for _, wd := range w.widgets {
		switch w.orientation {
		case SWLLayV:
			// Find the highest want of all widgets
			wantW = wh.Max(wd.WantW(), wantW)
		case SWLLayH:
			// Find the sum of all widgets wants
			wantW = wantW + wd.WantW()
		}
	}
	if w.insetBorder {
		wantW += 2
	}
	return wantW
}

func (w *ScrollingWidgetList) WantH() int {
	var wantH int
	for _, wd := range w.widgets {
		switch w.orientation {
		case SWLLayV:
			// Find the sum of all widgets wants
			wantH = wantH + wd.WantH()
		case SWLLayH:
			// Find the highest want of all widgets
			wantH = wh.Max(wd.WantH(), wantH)
		}
	}
	if w.insetBorder {
		wantH += 2
	}
	return wantH
}

func (w *ScrollingWidgetList) MinW() int {
	var minW int
	for _, wd := range w.widgets {
		switch w.orientation {
		case SWLLayV:
			// Find the highest minimum width of all widgets
			minW = wh.Max(wd.MinW(), minW)
		case SWLLayH:
			// Find the sum of all widget minimum widgets
			minW = minW + wd.MinW()
		}
	}
	return minW
}

func (w *ScrollingWidgetList) MinH() int {
	var minH int
	for _, wd := range w.widgets {
		switch w.orientation {
		case SWLLayV:
			minH = minH + wd.MinH()
		case SWLLayH:
			minH = wh.Max(wd.MinH(), minH)
		}
	}
	return minH
}

// Find the currently active widget, there should be only one.
func (w *ScrollingWidgetList) findActiveIdx() int {
	for i := range w.widgets {
		if w.widgets[i].Active() {
			return i
		}
	}
	return -1
}

func (w *ScrollingWidgetList) findActive() Widget {
	for i := range w.widgets {
		if w.widgets[i].Active() {
			return w.widgets[i]
		}
	}
	return nil
}

func (w *ScrollingWidgetList) findActiveOrFirst() Widget {
	if act := w.findActive(); act != nil {
		return act
	}
	// Didn't find one, return the first
	if len(w.widgets) > 0 {
		return w.widgets[0]
	}
	return nil
}

func (w *ScrollingWidgetList) ActivateWidget(n Widget) {
	for i := range w.widgets {
		w.widgets[i].SetActive(w.widgets[i] == n)
	}
}

func (w *ScrollingWidgetList) ActivateNext() bool {
	var found bool
	for i := range w.widgets {
		if found && w.widgets[i].Focusable() {
			w.widgets[i].SetActive(true)
			return true
		} else if w.widgets[i].Active() {
			found = true
			w.widgets[i].SetActive(false)
		}
	}
	return false
}

func (w *ScrollingWidgetList) ActivatePrev() bool {
	var found bool
	for i := len(w.widgets) - 1; i >= 0; i-- {
		if found && w.widgets[i].Focusable() {
			w.widgets[i].SetActive(true)
			return true
		} else if w.widgets[i].Active() {
			found = true
			w.widgets[i].SetActive(false)
		}
	}
	return false
}

func (w *ScrollingWidgetList) SetOrientation(o ScrollingWidgetListOrient) { w.orientation = o }
func (w *ScrollingWidgetList) WidgetCount() int                           { return len(w.widgets) }
func (w *ScrollingWidgetList) IndexOf(n Widget) int {
	for i := range w.widgets {
		if w.widgets[i] == n {
			return i
		}
	}
	return -1
}

func (w *ScrollingWidgetList) FindById(id string) Widget {
	for i := range w.widgets {
		if w.widgets[i].Id() == id {
			return w.widgets[i]
		}
	}
	return nil
}

func (w *ScrollingWidgetList) Contains(n Widget) bool {
	return w.IndexOf(n) >= 0
}

func (w *ScrollingWidgetList) Replace(n, with Widget) {
	idx := w.IndexOf(n)
	if idx == -1 {
		// 'n' isn't in layout. Bail out.
		return
	}
	w.Delete(n)
	w.Insert(with, idx)
}

func (w *ScrollingWidgetList) AddAll(n Widget, more ...Widget) {
	w.Add(n)
	for i := range more {
		w.Add(more[i])
	}
}

func (w *ScrollingWidgetList) Add(n Widget) {
	if w.Contains(n) {
		// If the widget is already in the layout, move it to the end
		w.Delete(n)
	}
	w.widgets = append(w.widgets, n)
	w.updateWidgetLayouts()
}

func (w *ScrollingWidgetList) Insert(n Widget, idx int) {
	if idx >= len(w.widgets) {
		w.Add(n)
		return
	}
	if pos := w.IndexOf(n); pos >= 0 {
		if pos < idx {
			idx--
		}
		w.Delete(n)
	}
	w.widgets = append(w.widgets[:idx], append([]Widget{n}, w.widgets[idx:]...)...)
}

// Remove all children from this widget
func (w *ScrollingWidgetList) Clear() { w.widgets = []Widget{} }

func (w *ScrollingWidgetList) Delete(n Widget) {
	for i := 0; i < len(w.widgets); i++ {
		if w.widgets[i] == n {
			w.DeleteIndex(i)
			return
		}
	}
}

func (w *ScrollingWidgetList) DeleteIndex(idx int) {
	if idx < len(w.widgets) {
		w.widgets = append(w.widgets[:idx], w.widgets[idx+1:]...)
	}
}

func (w *ScrollingWidgetList) updateWidgetLayouts() {
	switch w.orientation {
	case SWLLayV:
		for _, wd := range w.widgets {
			wd.HandleResize((&Coord{X: w.w, Y: wd.WantH()}).ResizeEvent())
			w.updateSWLVWidgetPos(wd)
		}
	case SWLLayH:
		for _, wd := range w.widgets {
			wd.HandleResize((&Coord{X: wd.WantW(), Y: w.h}).ResizeEvent())
			w.updateSWLHWidgetPos(wd)
		}
	}
}

// The Layout should have a static Size set at this point that we can use
// All widgets are being aligned to the Top-Left
//
// The position and size of each widget before this should be correct
// This widget should also know its size by now. We just need to
// position it relative to the layout.
func (w *ScrollingWidgetList) updateSWLVWidgetPos(wd Widget) {
	c := Coord{}
	for i := range w.widgets {
		if w.widgets[i] == wd {
			if i > 0 {
				c.Y += 1
			}
			break
		}
		// We only care about the Y & H of the widget before this one.
		if w.widgets[i].Visible() {
			c.Y = w.widgets[i].GetY() + w.widgets[i].GetH()
		}
	}

	if wd.GetW() < w.w {
		c.X = int((float64(w.w) / 2) - (float64(wd.GetW()) / 2))
	} else {
		c.X = 0
	}
	if w.insetBorder {
		c.X += 1
		c.Y += 1
	}
	wd.SetPos(c)
}

func (w *ScrollingWidgetList) updateSWLHWidgetPos(wd Widget) {
	c := Coord{}
	for i := range w.widgets {
		if w.widgets[i] == wd {
			if i > 0 {
				c.X += 1
			}
			break
		}
		if w.widgets[i].Visible() {
			c.X = w.widgets[i].GetX() + w.widgets[i].GetW()
		}
	}

	// Is the Y of this tricky?
	c.Y = 0
	if w.insetBorder {
		c.X += 1
		c.Y += 1
	}
	wd.SetPos(c)
}

func (w *ScrollingWidgetList) SetTabDisabled(b bool)            { w.disableTab = b }
func (w *ScrollingWidgetList) SetBordered(b bool)               { w.insetBorder = b }
func (w *ScrollingWidgetList) SetLogger(l func(string, ...any)) { w.logger = l }
func (w *ScrollingWidgetList) Log(txt string, args ...any) {
	if w.logger != nil {
		txt = fmt.Sprintf("%s:%s", time.Now().Format(time.TimeOnly), txt)
		w.logger(txt, args...)
	}
}

func (w *ScrollingWidgetList) SetEmptyWidget(wd Widget) { w.emptyWidget = wd }