#!/usr/bin/env ruby
# coding: utf-8

# http://docs.gitlab.com/ee/workflow/repository_mirroring.html
# https://gitlab.com/gitlab-org/gitlab-ee/issues/767

require 'net/http'
require 'uri'
require 'cgi'
require 'json'

class GitLabCE
	def initialize(api_uri, api_key, project_id)
		@api_uri = URI(api_uri)
		unless @api_uri.path.end_with?("/")
			@api_uri.path += "/"
		end
		@api_key = api_key.to_s
		@project_id = project_id.to_s

		@connections = {}
		@cache = {}

		# API docs suck, just look at `lib/api/projects.rb`
		@vars = [
			:builds_enabled,                                  # create | create-user | edit
			:container_registry_enabled,                      # create |             | edit
			:default_branch                                   #        | create-user | edit
			:description,                                     # create | create-user | edit
			:import_url,                                      # create | create-user |
			:issues_enabled,                                  # create | create-user | edit
			:lfs_enabled,                                     # create | create-user | edit
			:merge_requests_enabled,                          # create | create-user | edit
			:name,                                            # create | create-user | edit
			:namespace_id,                                    # create |             |
			:only_allow_merge_if_build_succeeds,              # create | create-user | edit
			:path,                                            # create |             | edit
			:public,                                          # create | create-user | edit
			:public_builds,                                   # create | create-user | edit
			:request_access_enabled,                          # create | create-user | edit
			:shared_runners_enabled,                          # create | create-user | edit
			:snippets_enabled,                                # create | create-user | edit
			:visibility_level,                                # create | create-user | edit
			:wiki_enabled,                                    # create | create-user | edit
			:only_allow_merge_if_all_discussions_are_resolved # create | create-user | edit
		]

		@vars = [
			"builds_enabled",
			"container_registry_enabled",
			"default_branch",
			"description",
			"issues_enabled",
			"lfs_enabled",
			"merge_requests_enabled",
			"name",
			"only_allow_merge_if_all_discussions_are_resolved",
			"only_allow_merge_if_build_succeeds",
			"path",
			"public",
			"public_builds",
			"request_access_enabled",
			"shared_runners_enabled",
			"snippets_enabled",
			"visibility_level",
			"wiki_enabled",
		]
	end

	def _connection(uri)
		key=URI(uri.scheme+":")
		key.host = uri.host
		key.port = uri.port

		@connections[key] ||= Net::HTTP::start(uri.host, uri.port, :use_ssl => uri.scheme == 'https')
		return @connections[key]
	end

	def _info
		unless @cache.has_key?(:info)
			req = Net::HTTP::Get.new(@api_uri + "projects/" + CGI::escape(@project_id))
			req.add_field("PRIVATE-TOKEN", @api_key)
			con = _connection(req.uri)
			res = con.request(req)
			if res.code != "200"
				throw res
			end
			@cache[:info] = JSON::parse(res.body)
		end
		return @cache[:info]
	end

	def get_meta
		return _info.select{|k,v| @vars.include?(k)}
	end

	def set_meta(map)
		illegal = map.select{|k,v| not @vars.include?(k)}
		if illegal.count > 0
			throw illegal
		end

		req = Net::HTTP::Put.new(@api_uri + "projects/" + CGI::escape(_info["id"].to_s))
		req.add_field("PRIVATE-TOKEN", @api_key)
		req.add_field("Content-Type", "application/json")
		req.body = JSON::dump(map)
		con = _connection(req.uri)
		res = con.request(req)
		if res.code != "200"
			throw res
		end
		@cache[:info] = JSON::parse(res.body)
		return get_meta
	end

	def pushURL
		return _info["ssh_url_to_repo"]
	end

	def pullURL
		return _info["http_url_to_repo"]
	end

	def create(id, map)
		if map.has_key?("mirror")
			map["import_url"] = map["mirror"]
			map.delete("mirror")
		end
		req = Net::HTTP::Post.new(@api_uri + "projects")
		req.add_field("PRIVATE-TOKEN", @api_key)
		req.add_field("Content-Type", "application/json")
		req.body = JSON::dump(map)
		con = _connection(req.uri)
		res = con.request(req)
	end

	def capabilities
		return [
			[ "get-meta", @vars ].flatten,
			[ "set-meta", @vars ].flatten,
			[ "push-url" ],
			[ "pull-url" ],
		]
	end

	def finish
		@connections.each do |k,v|
			v.finish()
		end
		@connections = {}
	end
end