local util = {}
local magick = require("magick")
local db = require("lapis.db")

local Avatars = require("models").Avatars
local Users = require("models").Users

function util.get_user_avatar_url(req, user)
  if not user.avatar_id then
    return "/avatars/default.webp"
  end
  return Avatars:find(user.avatar_id).file_path
end

function util.validate_and_create_image(input_image, filename)
  local img = magick.load_image_from_blob(input_image)

  if not img then
    return false
  end

  img:strip()
  img:set_gravity("CenterGravity")

  local width, height = img:get_width(), img:get_height()
  local min_dim = math.min(width, height)
  if min_dim > 256 then
    local ratio = 256.0 / min_dim
    local new_w, new_h = width * ratio, height * ratio
    img:resize(new_w, new_h)
  end

  width, height = img:get_width(), img:get_height()
  local crop_size = math.min(width, height)
  local x_offset = (width - crop_size) / 2
  local y_offset = (height - crop_size) / 2
  img:crop(crop_size, crop_size, x_offset, y_offset)

  img:set_format("webp")
  img:set_quality(85)

  img:write(filename)
  img:destroy()
  return true
end

function util.get_logged_in_user(req)
  if req.session.session_key == nil then
    return nil
  end

  local session = db.select('* FROM "sessions" WHERE "key" = ? AND "expires_at" > "?" LIMIT 1', req.session.session_key, os.time())
  if #session > 0 then
    return Users:find({id = session[1].user_id})
  end

  return nil
end

return util