#!/usr/bin/env ruby

#
# gen-logo.rb: generate svg logo
#
# 
# notes: 
# * used #4e86b1 as base color
# * used color wheel to generate complimentary colors:
#   https://www.sessions.edu/color-calculator/ 
#

require 'luigi-template'

CONFIG = {
  # svg dimensions
  # FIXME: these aren't working
  svg_width:  108,
  svg_height: 90,

  # show background?
  bg: false,

  # animation duration, in seconds
  duration: 20,

  # animation delay coefficients
  #   delay = (y - 1) * YC + (x - 1) * XC
  delay_coefficients: {
    y: 1.0,
    x: 0.2,
  },

  # animation color keyframes
  colors: [
    { c: '#ffffff', t: 0 },
    { c: '#4e86b1', t: 0.333 },
    { c: '#4eb179', t: 0.666 },
    { c: '#ffffff', t: 1 },
  ],

  # dot sizes
  dot_width: 12,
  dot_height: 10,

  # square coordinates
  dots: [
    # P (0)
    { x: 1, y: 1 },
    { x: 1, y: 2 },
    { x: 1, y: 3 },
    { x: 1, y: 4 },
    { x: 1, y: 5 },
    { x: 1, y: 5 },

    # P (1)
    { x: 2, y: 1 },
    { x: 2, y: 3 },

    # P (2)
    { x: 3, y: 1 },
    { x: 3, y: 2 },
    { x: 3, y: 3 },

    # T (0)
    { x: 5, y: 1 },

    # T (1)
    { x: 6, y: 1 },
    { x: 6, y: 2 },
    { x: 6, y: 3 },
    { x: 6, y: 4 },
    { x: 6, y: 5 },

    # T (2)
    { x: 7, y: 1 },

    # _ (0-7)
    { x: 1, y: 7 },
    { x: 2, y: 7 },
    { x: 3, y: 7 },
    { x: 4, y: 7 },
    { x: 5, y: 7 },
    { x: 6, y: 7 },
    { x: 7, y: 7 },
  ],
}

# build template cache
TEMPLATES = Luigi::Cache.new({
  svg: %{
    <?xml version="1.0"?>
    <svg
      xmlns="http://www.w3.org/2000/svg"
      version="1.1"
      viewBox="0 0 %{width} %{height}"
    >
      %{bg}

      <g fill='white' stroke='black'>
        %{dots}
      </g>
    </svg>
  },

  bg: %{
    <rect x='0' y='0' width='100%' height='100%' fill='black'/>
  },

  dot: %{
    <rect x='%{x}' y='%{y}' width='%{width}' height='%{height}'>
      <animate
        dur='%{duration}s'
        begin='%{begin}'
        values='%{values}'
        keyTimes='%{times}'
        attributeName='fill'
        repeatCount='indefinite'
      />
    </rect>
  },
}.reduce({}) do |r, row|
  r[row[0]] = row[1].strip.gsub(/(?<!\?\>)\s+/, ' ')
  r
end)

# keyframe color values
VALUES = CONFIG[:colors].map { |row|
  row[:c]
}.join(';').freeze

# keyframe times
TIMES = CONFIG[:colors].map { |row|
  ('%1.3f' % row[:t]).gsub(/0+$/, '').gsub(/\.$/, '')
}.join(';').freeze

# get delay coefficients
YC = CONFIG[:delay_coefficients][:y]
XC = CONFIG[:delay_coefficients][:x]

# generate svg
svg = TEMPLATES[:svg].run({
  # svg dimensions
  width:  CONFIG[:svg_width],
  height: CONFIG[:svg_height],

  # background
  bg: CONFIG[:bg] ? TEMPLATES[:bg].run({}) : '',

  # dots
  dots: CONFIG[:dots].map { |row|
    y = row[:y] * CONFIG[:dot_height]
    x = row[:x] * CONFIG[:dot_width]

    # calculate animation delay
    delay = (row[:y] - 1) * YC + (row[:x] - 1) * XC

    TEMPLATES[:dot].run(row.merge({
      x:        x - 5,
      y:        y,
      width:    CONFIG[:dot_width],
      height:   CONFIG[:dot_height],

      duration: CONFIG[:duration],
      begin:    '%1.1fs' % [delay],
      values:   VALUES,
      times:    TIMES,
    }))
  }.join,
})

# apply cleanups to svg, then write it to stdout
puts([
  [ /> +</,    '><'   ],
  [ /\s+>/m,  '>'     ],
  [ / +\/>/,  '/>'    ],
  [ / +<svg/, '<svg'  ],
].reduce(svg) do |r, row|
  # apply cleanup
  r.gsub(row[0], row[1])
end)