# coding: utf-8
require 'CSV'
require 'yaml'
require 'mysql2'
require 'optparse'

load 'config.rb'

Options = {}
OptionParser.new do |opts|
  opts.banner = "Usage: invoice.rb [options]"
  
  opts.on("-d", "--draft", "Generate invoices with 'DRAFT' watermark") do |d|
    Options[:draft] = d
  end
  opts.on("-v", "--verbose", "Run verbosely") do |v|
    Options[:verbose] = v
  end
  opts.on("-s", "--silent", "Run silently (overrules -v)") do |s|
    Options[:silent] = true
    Options[:verbose] = false
  end
end.parse!

db = Mysql2::Client.new(:host => DB_HOST, :username => DB_USER, :database => DB_DB)

YAML_BASE = {"author": "Christoffer Müller Madsen", "city": "Aarhus", "from": ["Falstersgade 18, 4. th", "8000 Aarhus C"], 'currency': 'DKK', 'commasep': true, 'lang': 'danish', 'seriffont': 'Linux Libertine', 'sansfont': 'Linux Biolinum', 'fontsize': '10pt', 'geometry': 'a4paper, left=43mm, right=43mm, top=51mm, bottom=17mm', 'closingnote': %Q[Overfør venligst det anførte beløb via MobilePay til følgende telefonnummer i løbet af de næste 14 dage:

    +45 81 73 02 02

Med venlig hilsen
] }

Products = Hash.new
Names = Hash.new
Prices = Hash.new

# Initialize product and member hashses
db.query("SELECT * FROM products").each do |product|
  id = product['id']
  pretty_name = product['pretty_name']
  price = product['price']
  if Options[:verbose]
    puts "Found product: #{id} => #{pretty_name}, #{price}"
  end
  Products[id] = pretty_name
  Prices[id] = price
end

db.query("SELECT * FROM members").each do |member|
  Names[member['id']] = member['name']
end


class LogItem
  def initialize(time,person,product,amount: 1)
    @time = time
    @person = person
    @product = product
    @amount = amount
  end
  attr_accessor :time, :person, :product, :amount
end

def read_file(file)
  rows = Array.new
  CSV.foreach(file, col_sep: ';', converters: :float) do |row|
    rows << LogItem.new(row[0],row[1],row[2],amount: row[3])
  end
  rows
end

def read_db(db)
  rows = Array.new
  db.query("SELECT * FROM transactions").each do |row|
    if date_of_prev('monday').to_time < row["time"]
      rows << LogItem.new(row["time"], row["buyer"], row["product"], amount: row["amount"])
    end
  end
  rows
end

def partition_rows(rows)
  skyldnere = Hash.new
  rows.each do |row|
    skyldnere[row.person] = Hash.new unless skyldnere[row.person]
    skyldnere[row.person][row.product] = 0 unless skyldnere[row.person][row.product]
    skyldnere[row.person][row.product] += row.amount
  end
  skyldnere
end

def generate_receipt(skyldnere,draft)
  counter = 0
  skyldnere.each do |person, products|
    counter += 1
    yaml = YAML_BASE.clone
    yaml["to"] = Names[person]
    products.each do |product, amount|
      yaml["invoice-nr"] = Time.now.strftime('%Y%W') + "-" + counter.to_s
      yaml["service"] = Array.new unless yaml["service"]
      hash = {description: Products[product], pieceprice: Prices[product].to_i, price: Prices[product].to_i*amount, amount: amount}
      yaml["service"] << Hash[hash.map{ |k, v| [k.to_s, v] }]
    end

    if draft
      yaml["draft"] = "true"
      yaml["drafttext"] = "Udkast"
    end
    
    output = Hash[yaml.map{ |k, v| [k.to_s, v] }].to_yaml
    output += "---\n"
    File.open("./pandoc/details.yml","w") do |file|
      file << output
    end
    `cd pandoc/; make -B`
    `cp pandoc/output.pdf #{OUTPUT_PATH}/#{yaml["invoice-nr"]}.pdf`
    puts "#{person}: #{yaml["invoice-nr"]}.pdf" unless Options[:silent]
  end
end

# Utility

def date_of_next(day)
  date  = Date.parse(day)
  delta = date > Date.today ? 0 : 7
  date + delta
end

def date_of_prev(day)
  date = Date.parse(day)
  delta = date < Date.today ? 0 : 7
  date - delta
end

partition = partition_rows(read_db(db))
generate_receipt(partition,Options[:draft])