//
//  rhlibrary
//
//  The Radio Helsinki Rivendell Library
//
//
//  Copyright (C) 2016 Christian Pointner <equinox@helsinki.at>
//
//  This file is part of rhlibrary.
//
//  rhlibrary is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  any later version.
//
//  rhlibrary is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with rhlibrary. If not, see <http://www.gnu.org/licenses/>.
//

package main

import (
	"time"

	"code.helsinki.at/rhrd-go/player"
	"github.com/gotk3/gotk3/glib"
	"github.com/gotk3/gotk3/gtk"
)

var (
	playIcon  *gtk.Image = nil
	pauseIcon *gtk.Image = nil
)

func addPlayPauseButton(box *gtk.Box, p *player.PlayerChan) (err error) {
	var btn *gtk.Button
	if btn, err = gtk.ButtonNew(); err != nil {
		return
	}
	if playIcon, err = gtk.ImageNewFromIconName("media-playback-start", gtk.ICON_SIZE_LARGE_TOOLBAR); err != nil {
		return
	}
	if pauseIcon, err = gtk.ImageNewFromIconName("media-playback-pause", gtk.ICON_SIZE_LARGE_TOOLBAR); err != nil {
		return
	}
	btn.SetSizeRequest(42, 42)
	btn.SetImage(playIcon)
	btn.SetSensitive(false)

	btn.Connect("clicked", func(_ *gtk.Button) {
		if err := p.PlayPause(); err != nil {
			rhdl.Println(err) // TODO: feedback at GUI?
		}
	})

	p.AddStateChangeHandler(func(state player.State, _ interface{}) bool {
		glib.IdleAdd(func() {
			switch state {
			case player.IDLE:
				btn.SetImage(playIcon)
				btn.SetSensitive(false)
			case player.PAUSED:
				btn.SetImage(playIcon)
				btn.SetSensitive(true)
			case player.PLAYING:
				btn.SetImage(pauseIcon)
				btn.SetSensitive(true)
			}
		})
		return true
	}, nil)

	box.PackStart(btn, false, false, 0)
	return
}

func addStopButton(box *gtk.Box, p *player.PlayerChan) (err error) {
	var btn *gtk.Button
	if btn, err = gtk.ButtonNewFromIconName("media-playback-stop", gtk.ICON_SIZE_LARGE_TOOLBAR); err != nil {
		return
	}
	btn.SetSizeRequest(42, 42)
	btn.SetSensitive(false)

	btn.Connect("clicked", func(_ *gtk.Button) {
		if err := p.Stop(); err != nil {
			rhdl.Println(err) // TODO: feedback at GUI?
		}
	})

	p.AddStateChangeHandler(func(state player.State, _ interface{}) bool {
		glib.IdleAdd(func() {
			switch state {
			case player.IDLE:
				btn.SetSensitive(false)
			case player.PAUSED:
				btn.SetSensitive(true)
			case player.PLAYING:
				btn.SetSensitive(true)
			}
		})
		return true
	}, nil)

	box.PackStart(btn, false, false, 0)
	return
}

func addButtons(grid *gtk.Grid, p *player.PlayerChan) (err error) {
	var box *gtk.Box
	if box, err = gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 2); err != nil {
		return
	}

	if err = addPlayPauseButton(box, p); err != nil {
		return
	}
	if err = addStopButton(box, p); err != nil {
		return
	}

	grid.Attach(box, 1, 1, 1, 1)
	return
}

func addMeter(grid *gtk.Grid, p *player.PlayerChan) error {
	widget, err := getVUMeterWidget(p)
	if err != nil {
		return err
	}

	grid.Attach(widget, 2, 1, 1, 1)
	return nil
}

func getPlayTimeString(duration, pos time.Duration, countdown bool) string {
	t := time.Unix(0, 0).UTC()
	if countdown {
		return t.Add(duration).Add(-1 * pos).Format("-15:04:05.0")
	}
	return t.Add(pos).Format(" 15:04:05.0")
}

func addPlayTime(grid *gtk.Grid, p *player.PlayerChan) (err error) {
	var btn *gtk.Button
	if btn, err = gtk.ButtonNew(); err != nil {
		return err
	}

	countdown := false
	duration := time.Duration(0)
	pos := time.Duration(0)
	p.AddUpdateHandler(func(d time.Duration, p time.Duration, _ player.Meter, _ interface{}) bool {
		glib.IdleAdd(func() {
			duration = d
			pos = p
			btn.SetLabel(getPlayTimeString(duration, pos, countdown))
		})
		return true
	}, nil)

	btn.SetSizeRequest(128, 42)
	btn.SetRelief(gtk.RELIEF_NONE)
	btn.SetFocusOnClick(false)
	btn.SetLabel(getPlayTimeString(duration, pos, countdown))

	btn.Connect("clicked", func(_ *gtk.Button) {
		countdown = !countdown
		btn.SetLabel(getPlayTimeString(duration, pos, countdown))
	})
	if err = setCssStyle(&btn.Widget, ".button { border: 1px solid; border-color: #a1a1a1; font-weight: bold; font-size: 1.3em; }"); err != nil {
		return
	}

	grid.Attach(btn, 3, 1, 1, 1)
	return
}

func addScrubber(grid *gtk.Grid, p *player.PlayerChan) (err error) {
	var scale *gtk.Scale
	if scale, err = gtk.ScaleNew(gtk.ORIENTATION_HORIZONTAL, nil); err != nil {
		return
	}
	if err = scale.SetProperty("draw-value", false); err != nil {
		return
	}
	scale.SetRange(0, 1)
	scale.SetValue(0)

	scale.Connect("change-value", func(s *gtk.Scale, _ interface{}, pos float64) {
		if err := p.Seek(pos); err != nil {
			rhdl.Println(err) // TODO: feedback at GUI?
		}
	})
	scale.SetSensitive(false)

	p.AddUpdateHandler(func(duration time.Duration, pos time.Duration, _ player.Meter, _ interface{}) bool {
		glib.IdleAdd(func() {
			if duration > 0 {
				scale.SetValue(float64(pos) / float64(duration))
			} else {
				scale.SetValue(0)
			}
		})
		return true
	}, nil)

	p.AddStateChangeHandler(func(state player.State, _ interface{}) bool {
		glib.IdleAdd(func() {
			switch state {
			case player.IDLE:
				scale.SetSensitive(false)
			case player.PAUSED:
				scale.SetSensitive(true)
			case player.PLAYING:
				scale.SetSensitive(true)
			}
		})
		return true
	}, nil)

	grid.Attach(scale, 1, 2, 3, 1)
	return
}

func getPlayerWidget(p *player.PlayerChan) (gtk.IWidget, error) {
	var err error
	var grid *gtk.Grid
	if grid, err = gtk.GridNew(); err != nil {
		return nil, err
	}
	grid.SetOrientation(gtk.ORIENTATION_HORIZONTAL)
	grid.SetRowSpacing(8)
	grid.SetColumnSpacing(13)

	if err = addButtons(grid, p); err != nil {
		return nil, err
	}
	if err = addMeter(grid, p); err != nil {
		return nil, err
	}
	if err = addPlayTime(grid, p); err != nil {
		return nil, err
	}
	if err = addScrubber(grid, p); err != nil {
		return nil, err
	}

	grid.SetHAlign(gtk.ALIGN_CENTER)
	return grid, nil
}