#!/usr/bin/env ruby

# Example: sync all posts from a given account (excluding replies and reposts) to a local JSON file.
# When run again, it will only fetch new posts since the last time and add them to the file.
#
# We'll use the getAuthorFeed endpoint on the AppView here, which does not require authentication.

require 'bundler/setup'
require 'didkit'
require 'minisky'
require 'time'

if ARGV.length != 2
  puts "Usage: #{$PROGRAM_NAME} <handle | did> <posts.json>"
  exit 1
end

$did = DID.resolve_handle(ARGV[0]).to_s

if $did.empty?
  puts "Couldn't resolve handle: #{ARGV[0]}"
  exit 1
end

$posts_file = ARGV[1]

# create a client instance
bsky = Minisky.new('public.api.bsky.app', nil)

# print progress dots when loading multiple pages
bsky.default_progress = '.'

# load previously saved posts; we'll only fetch posts newer than the last saved before
posts = File.exist?($posts_file) ? JSON.parse(File.read($posts_file)) : []
latest_date = posts[0] && posts[0]['indexedAt']

if !posts.empty?
  last_date_fmt = Time.parse(latest_date).getlocal
  puts "Loaded #{posts.length} previously saved posts (last date: #{last_date_fmt})"
end

# fetch all posts from the profile feed (without replies) until the target timestamp
results = bsky.fetch_all('app.bsky.feed.getAuthorFeed',
  { actor: $did, filter: 'posts_no_replies', limit: 100 },
  field: 'feed',
  break_when: latest_date && proc { |x| x['post']['indexedAt'] <= latest_date }
)

new_posts = results.map { |x|
  x['post']
}.reject { |x|
  # skip reposts
  x['author']['did'] != $did
}.map { |x|
  # trim some data to save space
  x.slice('uri', 'cid', 'record', 'indexedAt')
}

posts = new_posts + posts

puts
puts "Fetched #{new_posts.length} new posts (total = #{posts.length})"

# save all new and old posts back to the file
File.write($posts_file, JSON.pretty_generate(posts))