class Pronto::Formatter::GitFormatter

def client_module
  raise NotImplementedError
end

def consolidate_comments(comments)
  comment = comments.first
  if comments.length > 1
    joined_body = join_comments(comments)
    Comment.new(comment.sha, joined_body, comment.path, comment.position)
  else
    comment
  end
end

def dedupe_comments(existing, comments)
  body = existing.map(&:body).join(' ')
  comments.reject { |comment| body.include?(comment.body) }
end

def existing_comments(*)
  raise NotImplementedError
end

def format(messages, repo, patches)
  client = client_module.new(repo)
  existing = existing_comments(messages, client, repo)
  comments = new_comments(messages, patches)
  additions = remove_duplicate_comments(existing, comments)
  submit_comments(client, additions)
  
  approve_pull_request(comments.count, additions.count, client) if defined?(self.approve_pull_request)
  "#{additions.count} Pronto messages posted to #{pretty_name} (#{existing.count} existing)"
end

def grouped_comments(comments)
  comments.group_by { |comment| [comment.path, comment.position] }
end

def join_comments(comments)
  comments.map { |comment| "- #{comment.body}" }.join("\n")
end

def line_number(*)
  raise NotImplementedError
end

def new_comment(message, patches)
  config.logger.log("Creating a comment from message: #{message.inspect}")
  sha = message.commit_sha
  body = config.message_format(self.class.name) % message.to_h
  path = message.path
  lineno = line_number(message, patches) if message.line
  Comment.new(sha, body, path, lineno)
end

def new_comments(messages, patches)
  comments = messages
    .uniq
    .map { |message| new_comment(message, patches) }
  grouped_comments(comments)
end

def pretty_name
  raise NotImplementedError
end

def remove_duplicate_comments(old_comments, new_comments)
  new_comments.each_with_object([]) do |(key, comments), memo|
    existing = old_comments[key]
    comments = dedupe_comments(existing, comments) if existing
    if config.consolidate_comments? && !comments.empty?
      comment = consolidate_comments(comments)
      memo.push(comment)
    else
      memo.concat(comments)
    end
  end
end

def submit_comments(*)
  raise NotImplementedError
end