module RbaRates

# File lib/rba_rates.rb, line 90
def fetch_cash_csv(fetch: nil)
  body = fetch ? fetch.call(CASH_CSV_URL) : RabbotHttp.fetch(CASH_CSV_URL)
  parse_cash_csv(body)
rescue StandardError
  nil
end

# File lib/rba_rates.rb, line 59
def fetch_exchange_csv(fetch: nil)
  body = fetch ? fetch.call(EXCHANGE_CSV_URL) : RabbotHttp.fetch(EXCHANGE_CSV_URL)
  parse_exchange_csv(body)
rescue StandardError
  nil
end

# File lib/rba_rates.rb, line 150
def format_cash(result)
  return format_missing("cash rate") unless result

  lines = [
    IrcFormat.report_header(tag: "RBA", title: "Cash rate target", style: STYLE_TITLE),
    "#{result[:rate]}% — as at #{result[:date]}",
    IrcFormat.report_footer("target cash rate", "Reserve Bank of Australia")
  ]
  lines.join("\n")
end

# File lib/rba_rates.rb, line 161
def format_missing(what)
  lines = [
    IrcFormat.report_header(tag: "RBA", title: what, style: STYLE_TITLE),
    "Rate data unavailable right now.",
    IrcFormat.report_footer("RBA statistics", "Reserve Bank of Australia")
  ]
  lines.join("\n")
end

# File lib/rba_rates.rb, line 139
def format_pair(result)
  return format_missing("exchange rate") unless result

  lines = [
    IrcFormat.report_header(tag: "RBA", title: result[:label], style: STYLE_TITLE),
    "#{result[:value]} — as at #{result[:date]}",
    IrcFormat.report_footer("daily indicative rate", "Reserve Bank of Australia")
  ]
  lines.join("\n")
end

# File lib/rba_rates.rb, line 121
def lookup_pair(pair, fetch: nil)
  series_id = resolve_series(pair)
  return nil unless series_id

  table = fetch_exchange_csv(fetch: fetch)
  return nil unless table

  value = table[:values][series_id]
  return nil unless value

  {
    series_id: series_id,
    label: SERIES_LABELS.fetch(series_id, series_id),
    value: value,
    date: table[:date]
  }
end

# File lib/rba_rates.rb, line 97
def parse_cash_csv(body)
  rows = CSV.parse(body.to_s)
  series_row = rows.find { |row| row[0].to_s.strip == "Series ID" }
  return nil unless series_row

  cash_index = series_row.index(CASH_SERIES_ID)
  return nil unless cash_index

  data_rows = rows.select do |row|
    row[0].to_s.match?(/\A(?:\d{2}-[A-Za-z]{3}-\d{4}|[A-Za-z]{3}-\d{4})\z/)
  end
  return nil if data_rows.empty?

  latest = data_rows.reverse.find { |row| !row[cash_index].to_s.strip.empty? }
  return nil unless latest

  {
    date: latest[0].to_s.strip,
    rate: latest[cash_index].to_s.strip
  }
rescue StandardError
  nil
end

# File lib/rba_rates.rb, line 66
def parse_exchange_csv(body)
  rows = CSV.parse(body.to_s)
  series_row = rows.find { |row| row[0].to_s.strip == "Series ID" }
  return nil unless series_row

  series_ids = series_row[1..]
  data_rows = rows.select { |row| row[0].to_s.match?(/\A\d{2}-[A-Za-z]{3}-\d{4}\z/) }
  return nil if data_rows.empty?

  latest = data_rows.last
  date = latest[0].to_s.strip
  values = {}
  series_ids.each_with_index do |series_id, index|
    next if series_id.to_s.strip.empty?

    value = latest[index + 1].to_s.strip
    values[series_id.to_s.strip] = value unless value.empty?
  end

  { date: date, values: values }
rescue StandardError
  nil
end

# File lib/rba_rates.rb, line 52
def resolve_series(pair)
  key = pair.to_s.strip.downcase.gsub(/[^a-z]/, "")
  return nil if key.empty?

  PAIR_ALIASES[key]
end