module RuboCop::Cop::Style::ConditionalCorrectorHelper

def assignment(node)
  *_, condition = *node
  Parser::Source::Range.new(node.loc.expression.source_buffer,
                            node.loc.expression.begin_pos,
                            condition.loc.expression.begin_pos)
end

def correct_branches(corrector, branches)
  branches.each do |branch|
    *_, assignment = *branch
    corrector.replace(branch.source_range, assignment.source)
  end
end

def correct_if_branches(corrector, cop, node)
  if_branch, elsif_branches, else_branch = extract_tail_branches(node)
  corrector.insert_before(node.source_range, lhs(if_branch))
  replace_branch_assignment(corrector, if_branch)
  correct_branches(corrector, elsif_branches)
  replace_branch_assignment(corrector, else_branch)
  corrector.insert_before(node.loc.end, indent(cop, lhs(if_branch)))
end

def remove_whitespace_in_branches(corrector, branch, condition, column)
  branch.each_node do |child|
    white_space = white_space_range(child, column)
    corrector.remove(white_space) if white_space.source.strip.empty?
  end
  [condition.loc.else, condition.loc.end].each do |loc|
    corrector.remove_preceding(loc, loc.column - column)
  end
end

def replace_branch_assignment(corrector, branch)
  _variable, *_operator, assignment = *branch
  corrector.replace(branch.source_range, assignment.source)
end

def white_space_range(node, column)
  expression = node.loc.expression
  begin_pos = expression.begin_pos - (expression.column - column - 2)
  Parser::Source::Range.new(expression.source_buffer,
                            begin_pos,
                            expression.begin_pos)
end