class RuboCop::Cop::Style::Next

def self.autocorrect_incompatible_with
  [Style::SafeNavigation]
end

def actual_indent(lines, buffer)
  lines.map { |lineno| buffer.source_line(lineno) =~ /\S/ }.min
end

def allowed_modifier_if?(node)
  if node.modifier_form?
    style == :skip_modifier_ifs
  else
    !min_body_length?(node)
  end
end

def autocorrect_block(corrector, node)
  next_code = "next #{node.inverse_keyword} #{node.condition.source}"
  corrector.insert_before(node, next_code)
  corrector.remove(cond_range(node, node.condition))
  corrector.remove(end_range(node))
  lines = reindentable_lines(node)
  return if lines.empty?
  reindent(lines, node.condition, corrector)
end

def autocorrect_modifier(corrector, node)
  body = node.if_branch || node.else_branch
  replacement =
    "next #{node.inverse_keyword} #{node.condition.source}\n" \
    "#{' ' * node.source_range.column}#{body.source}"
  corrector.replace(node, replacement)
end

def check(node)
  return unless node.body && ends_with_condition?(node.body)
  offending_node = offense_node(node.body)
  add_offense(offense_location(offending_node)) do |corrector|
    if offending_node.modifier_form?
      autocorrect_modifier(corrector, offending_node)
    else
      autocorrect_block(corrector, offending_node)
    end
  end
end

def cond_range(node, cond)
  end_pos = if node.loc.begin
              node.loc.begin.end_pos # after "then"
            else
              cond.source_range.end_pos
            end
  range_between(node.source_range.begin_pos, end_pos)
end

def end_followed_by_whitespace_only?(source_buffer, end_pos)
  /\A\s*$/.match?(source_buffer.source[end_pos..-1])
end

def end_range(node)
  source_buffer = node.source_range.source_buffer
  end_pos = node.loc.end.end_pos
  begin_pos = node.loc.end.begin_pos - node.loc.end.column
  begin_pos -= 1 if end_followed_by_whitespace_only?(source_buffer,
                                                     end_pos)
  range_between(begin_pos, end_pos)
end

def ends_with_condition?(body)
  return true if simple_if_without_break?(body)
  body.begin_type? && simple_if_without_break?(body.children.last)
end

def exit_body_type?(node)
  return false unless node.if_branch
  EXIT_TYPES.include?(node.if_branch.type)
end

def heredoc_lines(node)
  node.each_node(:dstr)
      .select(&:heredoc?)
      .map { |n| n.loc.heredoc_body }
      .flat_map { |b| (b.line...b.last_line).to_a }
end

def if_else_children?(node)
  node.each_child_node(:if).any?(&:else?)
end

def if_without_else?(node)
  node&.if_type? && !node.ternary? && !node.else?
end

def offense_location(offense_node)
  offense_begin_pos = offense_node.source_range.begin
  offense_begin_pos.join(offense_node.condition.source_range)
end

def offense_node(body)
  *_, condition = *body
  condition&.if_type? ? condition : body
end

def on_block(node)
  return unless node.send_node.send_type? &&
                node.send_node.enumerator_method?
  check(node)
end

def on_new_investigation
  # When correcting nested offenses, we need to keep track of how much
  # we have adjusted the indentation of each line
  @reindented_lines = Hash.new(0)
end

def on_while(node)
  check(node)
end

def reindent(lines, node, corrector)
  range  = node.source_range
  buffer = range.source_buffer
  target_indent = range.source_line =~ /\S/
  delta = actual_indent(lines, buffer) - target_indent
  lines.each do |lineno|
    reindent_line(corrector, lineno, delta, buffer)
  end
end

def reindent_line(corrector, lineno, delta, buffer)
  adjustment = delta + @reindented_lines[lineno]
  @reindented_lines[lineno] = adjustment
  if adjustment.positive?
    corrector.remove_leading(buffer.line_range(lineno), adjustment)
  elsif adjustment.negative?
    corrector.insert_before(buffer.line_range(lineno),
                            ' ' * -adjustment)
  end
end

def reindentable_lines(node)
  buffer = node.source_range.source_buffer
  # end_range starts with the final newline of the if body
  lines = (node.source_range.line + 1)...node.loc.end.line
  lines = lines.to_a - heredoc_lines(node)
  # Skip blank lines
  lines.reject { |lineno| /\A\s*\z/.match?(buffer.source_line(lineno)) }
end

def simple_if_without_break?(node)
  return false unless if_without_else?(node)
  return false if if_else_children?(node)
  return false if allowed_modifier_if?(node)
  !exit_body_type?(node)
end