#!/usr/bin/env ruby

require 'cgi'

# Levenshtein distance implementation taken from:
# https://stackoverflow.com/a/16323861/155351
def lev(s, t)
  m = s.length
  n = t.length
  return m if n == 0
  return n if m == 0

  d = Array.new(m+1) {Array.new(n+1)}

  (0..m).each {|i| d[i][0] = i}
  (0..n).each {|j| d[0][j] = j}
  (1..n).each do |j|
    (1..m).each do |i|
      d[i][j] =
        if s[i-1] == t[j-1]
          d[i-1][j-1]
        else
          [ d[i-1][j]+1,
            d[i][j-1]+1,
            d[i-1][j-1]+1,
          ].min
        end
    end
  end

  d[m][n]
end

def find_scheme_lev(screenshot_file_name, all_scheme_names)
  all_scheme_names
    .map {|scheme_name| [lev(screenshot_file_name, scheme_name), scheme_name]}
    .min
end

def find_scheme_naive(screenshot_file_name, all_scheme_names)
  naive_guess =
    screenshot_file_name
    .capitalize
    .gsub(/-(.)/) {|match| match[1].upcase}
    .gsub(/_(.)/) {|match| " #{match[1].upcase}"}

  return naive_guess if all_scheme_names.include?(naive_guess)
end

def build_screenshot_scheme_map
  all_scheme_names = Dir["schemes/*.itermcolors"].map { |path|
    File.basename(path, ".itermcolors")
  }

  found_schemes = []
  stragglers = []

  Dir['screenshots/*.png'].each do |path|
    screenshot_file_name = File.basename(path, '.png')

    if scheme_name = find_scheme_naive(screenshot_file_name, all_scheme_names)
      found_schemes << [screenshot_file_name, scheme_name]
      all_scheme_names.delete(scheme_name)
    else
      stragglers << screenshot_file_name
    end
  end

  stragglers.each do |screenshot_file_name|
    distance, scheme_name =
      find_scheme_lev(screenshot_file_name, all_scheme_names)

    if distance < 10
      found_schemes << [screenshot_file_name, scheme_name]
      all_scheme_names.delete(scheme_name)
    else
      found_schemes << [screenshot_file_name, nil]
    end
  end

  found_schemes.sort
end

build_screenshot_scheme_map.reject{|pair| pair.last.nil?}.each do |screenshot_name, scheme_name|
  puts <<-HTML

<p><a href="https://raw.githubusercontent.com/mbadolato/iTerm2-Color-Schemes/master/schemes/#{CGI.escape(scheme_name)}.itermcolors"><strong>#{scheme_name}</strong></a></p>

<p><img src="https://raw.githubusercontent.com/mbadolato/iTerm2-Color-Schemes/master/screenshots/#{CGI.escape(screenshot_name)}.png" alt="Screenshot"></p>
  HTML
end