require "./check"

module Scope
  @[Meta(name: "Mandelbrot", desc: "The mandelbrot set")]
  class Mandelbrot < Check
    def query
      <<-SQL
        WITH RECURSIVE Z(IX, IY, CX, CY, X, Y, I) AS (
            SELECT IX, IY, X::float, Y::float, X::float, Y::float, 0
            FROM (select -2.2 + 0.031 * i, i from generate_series(0,101) as i) as xgen(x,ix),
                (select -1.5 + 0.031 * i, i from generate_series(0,101) as i) as ygen(y,iy)
          UNION ALL
            SELECT IX, IY, CX, CY, X * X - Y * Y + CX AS X, Y * X * 2 + CY, I + 1
            FROM Z
            WHERE X * X + Y * Y < 16::float
            AND I < 100
        )
        SELECT array_to_string(array_agg(SUBSTRING(' .,,,-----++++%%%%@@@@#### ', LEAST(GREATEST(I,1),27), 1)),'') AS mandelbrot
        FROM (
          SELECT IX, IY, MAX(I) AS I
          FROM Z
          GROUP BY IY, IX
          ORDER BY IY, IX
        ) AS ZT
        GROUP BY IY
        ORDER BY IY
      SQL
    end
  end
end

# SQL modified from https://github.com/heroku/heroku-pg-extras/releases/tag/v1.2.3
#
# The MIT License (MIT)
#
# Copyright Â© Heroku 2008 - 2014
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
