#!/usr/bin/lua5.1
-- -*- Lua -*-
-- gitano-pre-receive-hook
--
-- Git (with) Augmented network operations -- pre-receive hook handler
--
-- Copyright 2012-2017 Daniel Silverstone <dsilvers@digital-scurf.org>
-- All rights reserved.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions
-- are met:
-- 1. Redistributions of source code must retain the above copyright
--    notice, this list of conditions and the following disclaimer.
-- 2. Redistributions in binary form must reproduce the above copyright
--    notice, this list of conditions and the following disclaimer in the
--    documentation and/or other materials provided with the distribution.
-- 3. Neither the name of the author nor the names of their contributors
--    may be used to endorse or promote products derived from this software
--    without specific prior written permission.
--
-- THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-- ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-- FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-- DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-- OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-- HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-- LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-- OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-- SUCH DAMAGE.
--
--

-- Gitano modules installed into /usr/share/lua/5.1/?.lua

local gitano = require "gitano"
local gall = require "gall"
local luxio = require "luxio"
local sio = require "luxio.simple"
local sp = require "luxio.subprocess"

gitano.config.lib_bin_path("/usr/lib/gitano/bin")
gitano.config.share_path("/usr/share/gitano")
gitano.i18n.set_langpack_path("/usr/share/gitano/lang") gitano.i18n.set_category()
gitano.plugins.load_plugins {"/etc/gitano/plugins", "/usr/lib/gitano/plugins"}

local start_log_level = gitano.log.get_level()
-- Clamp level at info until we have checked if the caller
-- is an admin or not
gitano.log.cap_level(gitano.log.level.INFO)
gitano.log.syslog.open()

local repo_root = luxio.getenv("GITANO_ROOT")
local username  = luxio.getenv("GITANO_USER") or "gitano/anonymous"
local keytag    = luxio.getenv("GITANO_KEYTAG") or "unknown"
local project   = luxio.getenv("GITANO_PROJECT") or ""
local source    = luxio.getenv("GITANO_SOURCE") or "ssh"
local running   = luxio.getenv("GITANO_RUNNING")

-- Check whether we are called through gitano-auth
if not running then
   return 0
end

-- Now load the administration data
gitano.config.repo_path(repo_root)
local admin_repo = gall.repository.new((repo_root or "") .. "/gitano-admin.git")

if not admin_repo then
   gitano.log.fatal(gitano.i18n.expand("ERROR_NO_ADMIN_REPO"));
end

local admin_head = admin_repo:get(admin_repo.HEAD)

if not admin_head then
   gitano.log.fatal(gitano.i18n.expand("ERROR_BAD_ADMIN_REPO"));
end

local config, msg = gitano.config.parse(admin_head)

if not config then
   gitano.log.critical(gitano.i18n.expand("ERROR_CANNOT_PARSE_ADMIN"))
   gitano.log.critical("  * " .. (msg or "No error?"))
   gitano.log.fatal(gitano.i18n.expand("ERROR_CANNOT_CONTINUE"))
end

-- Now, are we an admin?
if config.groups["gitano-admin"].filtered_members[username] then
   -- Yep, so blithely reset logging level
   gitano.log.set_level(start_log_level)
end

if not config.global.silent then
   -- Not silent, bump to chatty level automatically
   gitano.log.bump_level(gitano.log.level.CHAT)
end

local repo, msg = gitano.repository.find(config, project)
if not repo then
   gitano.log.critical(gitano.i18n.expand("ERROR_CANNOT_LOCATE_REPO"))
   gitano.log.critical("  * " .. (tostring(msg)))
   gitano.log.fatal(gitano.i18n.expand("ERROR_CANNOT_CONTINUE"))
end

if repo.is_nascent then
   gitano.log.fatal(gitano.i18n.expand("ERROR_REPO_IS_NASCENT", {name=repo.name}))
end

-- pre-receive can prevent updates. Its name is a bit misleading.
-- pre-receive is called once all the objects have been pushed, but before the
-- individual update hooks are called.  It gets the same input as post-receive
-- but can opt to reject the entire push.  If you need to make decisions based
-- upon multiple refs being updated simultaneously, then this is the badger for
-- you.

local updates = {}
for oldsha, newsha, refname in (sio.stdin:read("*a")):gmatch("([^ ]+) ([^ ]+) ([^\n]+)") do
   gitano.log.ddebug("pre-receive:", oldsha, newsha, refname)
   updates[refname] = {oldsha, newsha, oldsha=oldsha, newsha=newsha}
end

if repo:uses_hook("pre-receive") then
   gitano.log.debug("Configuring for pre-receive hook")
   gitano.actions.set_supple_globals("pre-receive")

   local msg = gitano.i18n.expand("RUNNING_PRE_RECEIVE_HOOK")

   gitano.log.info(msg)
   gitano.log.syslog.info(msg)

   local info = {
      username = username,
      keytag = keytag,
      source = source,
      realname = (config.users[username] or {}).real_name or "",
      email = (config.users[username] or {}).email_address or "",
   }
   local ok, msg = gitano.supple.run_hook("pre-receive", repo, info, updates)
   if not ok then
      gitano.log.crit(msg or gitano.i18n.expand("ERROR_NO_ERROR_FOUND"))
   end
   gitano.log.info(gitano.i18n.expand("FINISHED"))
end

gitano.log.syslog.close()

return 0
