// gomuks - A terminal Matrix client written in Go.
// Copyright (C) 2018 Tulir Asokan
//
// This program 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
// (at your option) any later version.
//
// This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

package messages

import (
	"bytes"
	"encoding/gob"
	"fmt"
	"time"

	"image/color"

	"maunium.net/go/gomuks/debug"
	"maunium.net/go/gomuks/interface"
	"maunium.net/go/gomuks/lib/ansimage"
	"maunium.net/go/gomuks/ui/messages/tstring"
	"maunium.net/go/tcell"
)

func init() {
	gob.Register(&ImageMessage{})
}

type ImageMessage struct {
	BaseMessage
	Homeserver string
	FileID     string
	data       []byte

	gmx ifc.Gomuks
}

// NewImageMessage creates a new ImageMessage object with the provided values and the default state.
func NewImageMessage(gmx ifc.Gomuks, id, sender, msgtype, homeserver, fileID string, data []byte, timestamp time.Time) UIMessage {
	return &ImageMessage{
		newBaseMessage(id, sender, msgtype, timestamp),
		homeserver,
		fileID,
		data,
		gmx,
	}
}

func (msg *ImageMessage) RegisterGomuks(gmx ifc.Gomuks) {
	msg.gmx = gmx

	debug.Print(len(msg.data), msg.data)
	if len(msg.data) == 0 {
		go func() {
			defer gmx.Recover()
			msg.updateData()
		}()
	}
}

func (msg *ImageMessage) NotificationContent() string {
	return "Sent an image"
}

func (msg *ImageMessage) updateData() {
	debug.Print("Loading image:", msg.Homeserver, msg.FileID)
	data, _, _, err := msg.gmx.Matrix().Download(fmt.Sprintf("mxc://%s/%s", msg.Homeserver, msg.FileID))
	if err != nil {
		debug.Print("Failed to download image %s/%s: %v", msg.Homeserver, msg.FileID, err)
		return
	}
	msg.data = data
}

func (msg *ImageMessage) Path() string {
	return msg.gmx.Matrix().GetCachePath(msg.Homeserver, msg.FileID)
}

// CopyFrom replaces the content of this message object with the content of the given object.
func (msg *ImageMessage) CopyFrom(from ifc.MessageMeta) {
	msg.BaseMessage.CopyFrom(from)

	fromImgMsg, ok := from.(*ImageMessage)
	if ok {
		msg.data = fromImgMsg.data
	}

	msg.RecalculateBuffer()
}

// CalculateBuffer generates the internal buffer for this message that consists
// of the text of this message split into lines at most as wide as the width
// parameter.
func (msg *ImageMessage) CalculateBuffer(width int) {
	if width < 2 {
		return
	}

	image, err := ansimage.NewScaledFromReader(bytes.NewReader(msg.data), 0, width, color.Black)
	if err != nil {
		msg.buffer = []tstring.TString{tstring.NewColorTString("Failed to display image", tcell.ColorRed)}
		debug.Print("Failed to display image:", err)
		return
	}

	msg.buffer = image.Render()
	msg.prevBufferWidth = width
}

// RecalculateBuffer calculates the buffer again with the previously provided width.
func (msg *ImageMessage) RecalculateBuffer() {
	msg.CalculateBuffer(msg.prevBufferWidth)
}