module Logfmt

# File lib/logfmt/parser.rb, line 12
def self.integer?(s)
  s.is_a?(Integer) || s.to_s.match(/\A[-+]?[0-9]+\Z/)
end

# File lib/logfmt/parser.rb, line 8
def self.numeric?(s)
  s.is_a?(Numeric) || s.to_s.match(/\A[-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?\Z/)
end

# File lib/logfmt/parser.rb, line 16
def self.parse(line)
  output = {}
  key, value = '', ''
  escaped = false
  state = GARBAGE
  i = 0
  line.each_char do |c|
    i += 1
    if state == GARBAGE
      if c > ' ' && c != '"' && c != '='
        key = c
        state = KEY
      end
      next
    end
    if state == KEY
      if c > ' ' && c != '"' && c != '='
        state = KEY
        key << c
      elsif c == '='
        output[key.strip] = true
        state = EQUAL
      else
        output[key.strip] = true
        state = GARBAGE
      end
      output[key.strip] = true if i >= line.length
      next
    end
    if state == EQUAL
      if c > ' ' && c != '"' && c != '='
        value = c
        state = IVALUE
      elsif c == '"'
        value = ''
        escaped = false
        state = QVALUE
      else
        state = GARBAGE
      end
      if i >= line.length
        if integer?(value)
          value = value.to_i
        elsif numeric?(value)
          fvalue = value.to_f
          value = fvalue if fvalue.finite?
        end
        output[key.strip] = value || true
      end
      next
    end
    if state == IVALUE
      if !(c > ' ' && c != '"')
        if integer?(value)
          value = value.to_i
        elsif numeric?(value)
          fvalue = value.to_f
          value = fvalue if fvalue.finite?
        end
        output[key.strip] = value
        state = GARBAGE
      else
        value << c
      end
      if i >= line.length
        if integer?(value)
          value = value.to_i
        elsif numeric?(value)
          fvalue = value.to_f
          value = fvalue if fvalue.finite?
        end
        output[key.strip] = value
      end
      next
    end
    if state == QVALUE
      if c == '\\'
        escaped = true
        value << '\\'
      elsif c == '"'
        if escaped
          escaped = false
          value.chop! << c
          next
        end
        output[key.strip] = value
        state = GARBAGE
      else
        escaped = false
        value << c
      end
      next
    end
  end
  output
end