lbcserb

#!/usr/bin/env ruby

require 'erb'

if ARGV.length < 5
    puts "Need at least 5 arguments.  Also, this is only for lbcs scripts.  How are you even seeing this?"
    exit 1
end

maindir=ARGV.shift
lbcsdir=ARGV.shift
container=ARGV.shift
templatefile=ARGV.shift
outputfile=ARGV.shift
type=ARGV.shift

if type == 'addon'
    addon=ARGV.shift
end

if type != "container" && type != "addon"
    puts "Unknown type #{type}"
    exit 1
end

if ! File.directory?(maindir)
    puts "maindir arg '#{maindir}' doesn't look like a directory"
    exit 1
end

if ! File.directory?(lbcsdir)
    puts "lbcsdir arg '#{lbcsdir}' doesn't look like a directory"
    exit 1
end

containerdir=File.join(maindir, 'containers', container)

if ! File.directory?(containerdir)
    puts "containerdir arg '#{containerdir}' doesn't look like a directory"
    exit 1
end

if type == 'addon'
    addondir=File.join(containerdir, 'addons', addon)

    if ! File.directory?(addondir)
        puts "addondir arg '#{addondir}' doesn't look like a directory"
        exit 1
    end
end

if ! File.exist?(templatefile)
    puts "templatefile arg '#{templatefile}' doesn't look like a file"
    exit 1
end

vals={}

vals['maindir']=maindir
vals['lbcsdir']=lbcsdir
vals['containerdir']=containerdir
vals['container']=container
vals['container_name']=container
vals['user']=%x{id -un}.strip
if type == 'addon'
    vals['addondir']=addondir
    vals['addon']=addon
    vals['addon_name']=addon
end

# All remaining args are "foo=bar" stuff to add to the
# erb variable list
for arg in ARGV[0..] do
    stuff = arg.split('=', 2)
    vals[stuff[0]] = stuff[1]
end

files = [
    File.join(maindir, 'config'),
    File.join(maindir, 'secrets'),
    File.join(lbcsdir, 'config'),
    File.join(lbcsdir, 'secrets'),
    File.join(containerdir, 'config'),
    File.join(containerdir, 'secrets'),
]
if type == 'addon'
    files << File.join(addondir, 'config')
    files << File.join(addondir, 'secrets')
end

def getvals(line)
  stuff = line.split('=', 2)
  if line =~ %r{^[a-z_].*="}
    return stuff[0], stuff[1].sub( %r{^"(.*)"$}, '\1' )
  elsif line =~ %r{^[a-z_].*='}
    return stuff[0], stuff[1].sub( %r{^'(.*)'$}, '\1' )
  else
    return stuff[0], stuff[1]
  end
end

# Get a list of the addons
if type == 'container'
    addons_arr=[]
    Dir[File.join(containerdir, 'addons', '*')].each do |addon|
      line = File.read(File.join(addon, 'config')).lines.grep(%r{^name=}).first
      stuff = getvals(line)
      addons_arr << stuff[1]
    end
    vals['addons'] = addons_arr.join(' ')
end

# Now get all the vals from all the config and secrets files
for varfile in files do
    if File.exist?(varfile)
        for line in File.read(varfile).lines do
            line = line.gsub(%r{#.*},'').strip

            # Ruby local variables must start with a lower case letter
            # or underscore.  Also we don't care about lines with no =
            if line =~ %r{^[a-z_].*=}
                stuff = getvals(line)
                vals[stuff[0]] = stuff[1]
            end
        end
    end
end

templatetext = File.read(templatefile)

newtext = ERB.new(templatetext, trim_mode: '-').result_with_hash(vals)

oldtext=''

if File.exist?(outputfile)
    oldtext = File.read(outputfile)
end

if oldtext != newtext
    File.open(outputfile, 'w') { |file| file.write(newtext) }
end