package main

import (
	"bytes"
	"image"
	_ "image/gif"
	"image/jpeg"
	_ "image/png"
	"io/ioutil"
	"log"
	"net/http"
	"os"
	"strings"

	"github.com/golang/freetype"
	"github.com/hamcha/clessy/tg"
	"github.com/llgcode/draw2d"
	"github.com/llgcode/draw2d/draw2dimg"

	"github.com/disintegration/imaging"
)

const unsplashUrl = "https://source.unsplash.com/random/1280x720"

var quoteFontData draw2d.FontData

func initunsplash() {
	fontfile, err := os.Open(*gillmt)
	assert(err)
	defer fontfile.Close()

	bytes, err := ioutil.ReadAll(fontfile)
	assert(err)

	font, err := freetype.ParseFont(bytes)
	assert(err)

	quoteFontData = draw2d.FontData{"gillmt", draw2d.FontFamilySans, draw2d.FontStyleBold}
	draw2d.RegisterFont(quoteFontData, font)

	log.Println("[unsplash] Loaded!")
}

func stripUnreadable(r rune) rune {
	if r == '\n' || r == '\t' {
		return ' '
	}
	if r < 32 || r >= 0x1f000 {
		return -1
	}
	return r
}

func unsplash(broker *tg.Broker, update tg.APIMessage) {
	if isCommand(update, "unsplash") {
		text := ""
		user := update.User

		if update.ReplyTo != nil {
			if update.ReplyTo.Text == nil {
				broker.SendTextMessage(update.Chat, "Non c'e' niente di 'ispiratore' in questo..", &update.MessageID)
				return
			}
			text = *(update.ReplyTo.Text)
			user = update.ReplyTo.User
		} else {
			if strings.Index(*(update.Text), " ") > 0 {
				text = strings.TrimSpace(strings.SplitN(*(update.Text), " ", 2)[1])
			}
		}

		// Cleanup chars
		text = strings.Map(stripUnreadable, text)

		author := user.FirstName
		if user.LastName != "" {
			author = user.FirstName + " " + user.LastName
		}
		author += " (" + user.Username + ")"

		if strings.TrimSpace(text) == "" {
			broker.SendTextMessage(update.Chat, "Non c'e' niente di 'ispiratore' in questo..", &update.MessageID)
			return
		}

		resp, err := http.Get(unsplashUrl)
		if err != nil {
			log.Println("[unsplash] HTTP request failed: %s\n", err.Error())
			broker.SendTextMessage(update.Chat, "<b>ERRORE!</b> @hamcha controlla la console!", &update.MessageID)
			return
		}
		defer resp.Body.Close()

		img, _, err := image.Decode(resp.Body)
		if err != nil {
			log.Println("[unsplash] Image decode error: %s\n", err.Error())
			broker.SendTextMessage(update.Chat, "<b>ERRORE</b>: Non riesco a leggere l'immagine", &update.MessageID)
			return
		}

		// Darken image
		img = imaging.AdjustBrightness(imaging.AdjustGamma(imaging.AdjustSigmoid(img, 0.5, -6.0), 0.8), -20)

		// Create target image
		bounds := img.Bounds()
		iwidth := float64(bounds.Size().X)
		iheight := float64(bounds.Size().Y)

		timg := image.NewRGBA(bounds)
		gc := draw2dimg.NewGraphicContext(timg)
		gc.SetFontData(quoteFontData)
		gc.DrawImage(img)
		gc.SetStrokeColor(image.Black)
		gc.SetFillColor(image.White)

		text = strings.ToUpper(strings.TrimSpace(text))
		gc.Restore()
		gc.Save()

		// Detect appropriate font size
		scale := iheight / iwidth * (iwidth / 10) * 0.8
		gc.SetFontSize(scale)
		gc.SetLineWidth(scale / 15)

		// Get NEW bounds
		left, top, right, bottom := gc.GetStringBounds(text)

		width := right - left
		texts := []string{text}
		if width*1.2 > iwidth {
			// Split text
			texts = splitCenter(text)

			// Get longest line
			longer := float64(0)
			longid := 0
			widths := make([]float64, len(texts))
			for id := range texts {
				tleft, _, tright, _ := gc.GetStringBounds(texts[id])
				widths[id] = tright - tleft
				if width > longer {
					longer = widths[id]
					longid = id
				}
			}

			// Still too big? Decrease font size again
			iter := 0
			for width*1.2 > iwidth && iter < 10 {
				scale *= (0.9 - 0.05*float64(iter))
				gc.SetFontSize(scale)
				left, top, right, bottom = gc.GetStringBounds(texts[longid])
				width = right - left
				iter++
			}
		}

		texts = append(texts, author)
		height := bottom - top + 20
		margin := float64(height / 50)
		txtheight := (height + margin) * float64(len(texts))

		gc.Save()
		for id, txt := range texts {
			gc.Save()
			left, _, right, _ = gc.GetStringBounds(txt)
			width = right - left

			x := (iwidth - width) / 2
			y := (iheight-txtheight)/2 + (height+margin*2)*float64(id+1)
			if id == len(texts)-1 {
				gc.SetFontSize(scale * 0.7)
				left, _, right, _ = gc.GetStringBounds(txt)
				width = right - left
				x = (iwidth - width) / 1.5
				y = (iheight-txtheight)/2 + (height+margin)*float64(id+1) + margin*6
			}

			gc.Translate(x, y)
			gc.StrokeString(txt)
			gc.FillString(txt)
			gc.Restore()
		}

		buf := new(bytes.Buffer)
		err = jpeg.Encode(buf, timg, &(jpeg.Options{Quality: 80}))
		if err != nil {
			log.Println("[unsplash] Image encode error: %s\n", err.Error())
			broker.SendTextMessage(update.Chat, "<b>ERRORE!</b> @hamcha controlla la console!", &update.MessageID)
			return
		}
		broker.SendPhoto(update.Chat, buf.Bytes(), "quote.jpg", "", &update.MessageID)
	}
}