require 'RMagick'
require 'aws-sdk'
include Magick

class MosaicImage

	def perform
		canvas = mosaic()

		# Resize
		width = 800
		height = 1200
		canvas = canvas.resize_to_fit(width,height)

		box(canvas)
		text(canvas)

		canvas
	end

	private

	def box(canvas)
		w = canvas.columns
		h = canvas.rows

		gc = Magick::Draw.new

		x1 = (w/2) - (w/4)
		y1 = (h/2) - (h * 0.05)
		x2 = x1 + (w/2)
		y2 = y1 + (h * 0.05)

		gc.stroke_width(1)
		gc.stroke('gray50')
		gc.fill('white')

		gc.rectangle(x1, y1, x2, y2)
		gc.draw(canvas)
	end

	def text(canvas)
		w = canvas.columns
		h = canvas.rows
		# puts(h)
		text_label = "SEE THE OUTFITS"

		pt = h / 30
		# puts(pt)

		gc = Magick::Draw.new
		gc.stroke('transparent')
		gc.font_family('Helvetica')

		gc.font_weight(Magick::NormalWeight)
		gc.pointsize(pt)

		gc.font_style(Magick::NormalStyle)
		gc.text_align(Magick::CenterAlign)

		metrics = gc.get_type_metrics(text_label)
		# puts(metrics)
		# gc.text(w/2, h/2 + ((metrics.pixels_per_em.y / (metrics.bounds.y2 - metrics.bounds.y1) ) / 2).round, text_label)
		gc.text(w/2, h/2 - ((metrics.max_advance + metrics.descent) /2), text_label)

		gc.draw(canvas)
	end

	def mosaic()
		gc = Magick::ImageList.new

		img = 1
		5.times do
		    gc.read("img"+img.to_s+".jpg")
		    img += 1
		end

		b = Magick::ImageList.new
		page = Magick::Rectangle.new(0,0,0,0)
		gc.scene = 0
		3.times do |i|
		    3.times do |j|
		        b << gc.scale(1)
		        page.x = j * b.columns
		        page.y = i * b.rows
		        b.page = page
		        (gc.scene += 1) rescue gc.scene = 0
		    end
		end

		b.mosaic
	end

end

# Generate image and write to s3
canvas = MosaicImage.new().perform
s3 = Aws::S3::Resource.new
bucket = s3.bucket('my-bucket')
bucket.object('test/canvas.png').put(body: canvas.to_blob)

# write locally as well
canvas.write("canvas.png")