#!/usr/bin/env ruby
#
# etl [run] <pipeline.rb> [options]      ('run' is optional)
#
# executable of the gem datapipeline; in this repository bin/etl loads the bundle first
#
#   --from=DATE --till=DATE   in DataPipeline.params, also passed on to the pipeline script
#   --param key=value         in DataPipeline.params[:key], repeatable
#   --dry-run                 run everything, write nothing, print the first rows
#   --limit=N                 only the first N source rows
#   --verbose                 log level debug, --quiet only warnings (default info)
#   --lock=FILE               exclusive lock for the whole script, exit 3 when another run holds it
#   --name=value              any other option: DataPipeline.params[:name] and passed on to the script
#
# exit code: 0 ok, 1 aborted, 2 finished with rejected rows, 3 locked by another run
#
require 'optparse'
require 'logger'
require_relative '../lib/datapipeline'

options = { settings: { log_level: Logger::INFO }, passthrough: [] }
DataPipeline.params = {}
parser = OptionParser.new do |opts|
  opts.banner = "Usage: etl [run] PIPELINE.rb [options]\n\n  etl examples/kunden_import.rb --dry-run\n"
  opts.on('--from=DATE', String) { |v| DataPipeline.params[:from] = v; options[:passthrough] << "--from=#{v}" }
  opts.on('--till=DATE', String) { |v| DataPipeline.params[:till] = v; options[:passthrough] << "--till=#{v}" }
  opts.on('--param KEY=VALUE', String) do |v|
    key, value = v.split('=', 2)
    DataPipeline.params[key.to_sym] = value
  end
  opts.on('--dry-run') { options[:settings][:dry_run] = true }
  opts.on('--limit=N', Integer) { |v| options[:settings][:limit] = v }
  opts.on('--verbose') { options[:settings][:log_level] = Logger::DEBUG }
  opts.on('--quiet') { options[:settings][:log_level] = Logger::WARN }
  opts.on('--lock=FILE', String) { |v| options[:lock] = v }
end

# own options for the parser, everything else (also --name=value of the script) goes to the script
own = []
args = []
argv = ARGV.dup
while (arg = argv.shift)
  if arg.match?(/\A--(from|till|param|dry-run|limit|verbose|quiet|lock)(=|\z)/)
    own << arg
    own << argv.shift if %w[--param --limit --from --till].include?(arg)
  else
    args << arg
  end
end
parser.parse(own)
args.shift if args.first == 'run'
script = args.shift
DataPipeline.params.merge!(DataPipeline.parse_params(args)) { |_key, own_value, _| own_value }
abort parser.help if script.nil?
abort "etl: #{script} not found\n\n#{parser.help}" unless File.exist?(script)

DataPipeline.settings(options[:settings])

begin
  script_lock = DataPipeline::Lock.new(options[:lock]).acquire if options[:lock]   # held until the process ends
rescue DataPipeline::LockError => e
  warn "#{File.basename(script)}: #{e.message}"
  exit 3
end

# the pipeline script sees only its own arguments
ARGV.replace(options[:passthrough] + args)

begin
  load File.expand_path(script)
rescue StandardError => e
  warn "#{File.basename(script)}: #{e.class}: #{e.message}"
  exit(e.is_a?(DataPipeline::LockError) ? 3 : 1)
end

runs = DataPipeline.runs
exit 3 if runs.any? { |stats| stats.error.is_a?(DataPipeline::LockError) }
exit 1 if runs.any?(&:error)
exit 2 if runs.any? { |stats| stats.rejected.positive? }
exit 0