#!/usr/bin/lua5.2
telemver = "0.3 // 2018-05-04"
require("pl.strict")
file = require("pl.file")
io = require("io")
lfs = require("lfs")
os = require("os")
path = require("pl.path")
string = require("string")
table = require("table")
_BBS_ROOT = "/var/bbs/"
-- Global var declarations
username = os.getenv("USER") -- TODO: This is, obviously, not secure and will need to be updated
boards = {} -- Array of board names, alphaetically sorted
board_names = {} -- Set of board names, must always be consistent with boards
current_board = "" -- String, name of current board, must be in boards and board_names
current_board_threads = {} -- Array of thread tables, containing threads associated with current_board
current_thread = {} -- Active thread table, always an element of current_board_threads
current_thread_posts = {} -- Array of post tables, containing posts associated with current_thread
current_post_index = nil -- Integer index into current_thread_posts
-- Utility functions
function cat_file(filename)
io.write(file.read(filename))
end
function getchar()
os.execute("/bin/stty -icanon")
local char = io.read(1)
os.execute("/bin/stty icanon")
return char
end
function dispatch_loop(dispatch_table, quit_char, prompt_func, err_str)
repeat
-- Show prompt and read 1 char from keyboard
io.write(prompt_func())
local c = getchar()
if c ~= "\n" then io.write("\n") end
-- Use char as index into dispatch table
if c == "\n" then
-- pass
elseif dispatch_table[c] == nil then
print(err_str)
else
dispatch_table[c]()
end
until c == quit_char
end
-- Internals
function update_boards()
for board in lfs.dir(path.join(_BBS_ROOT, "boards")) do
if string.sub(board, 1, 1) ~= "." and not board_names[board] then
board_names[board] = true
table.insert(boards, board)
end
end
table.sort(boards)
end
function check_at_board()
if current_board == "" then
print("Not at any board! Hit `l` to list boards, `g` to go to one.")
end
return current_board ~= ""
end
function get_threads(board)
local threads = {}
for threaddir in lfs.dir(path.join(_BBS_ROOT, "boards", board)) do
if string.sub(threaddir, 1,1) == "." then goto continue end
if threaddir == "topic" then goto continue end
local thread = {}
thread.directory = path.join(_BBS_ROOT, "boards", board, threaddir)
local _, _, timestamp, author = string.find(threaddir, "(%d+)-(%g+)")
thread.timestamp = tonumber(timestamp)
thread.author = author
io.input(path.join(thread.directory, "subject"))
thread.subject = io.read("*line")
io.input(io.stdin)
local posts = get_posts(thread)
thread.post_count = #posts
thread.updated = 0
for _, post in ipairs(posts) do
if post.timestamp > thread.updated then
thread.updated = post.timestamp
end
end
table.insert(threads, thread)
::continue::
end
table.sort(threads, function(x,y) return x.updated > y.updated end)
return threads
end
function get_posts(thread)
local posts = {}
for postfile in lfs.dir(thread.directory) do
if string.sub(postfile, 1,1) == "." then goto continue end
if postfile == "subject" then goto continue end
local post = {}
post.filename = path.join(thread.directory, postfile)
local _, _, timestamp, author = string.find(postfile, "(%d+)-(%a+)")
post.timestamp = tonumber(timestamp)
post.author = author
table.insert(posts, post)
::continue::
end
table.sort(posts, function(x,y) return x.timestamp < y.timestamp end)
return posts
end
-- Commands
function do_board()
-- Creates a new (empty) board
-- Get details
io.write("New board name? (Max 18 chars) ")
local board = string.upper(io.read())
if string.len(board) > 18 then
print("Board names must be 18 characters or less!")
return
elseif string.len(board) == 0 then
print("New board cancelled.")
return
end
io.write("Board topic? (Max 48 chars)")
local desc = io.read()
if string.len(desc) > 48 then
print("Board topics must be 48 characters or less!")
return
end
-- Create directory
local board_dir = path.join(_BBS_ROOT, "boards", board)
lfs.mkdir(board_dir)
-- Write topic file
local topic_file = path.join(board_dir, "topic")
file.write(topic_file, desc)
-- Update representation of BBS
board_names[board] = true
table.insert(boards, board)
table.sort(boards)
-- Done!
print("Board created.")
end
function do_go()
io.write("Go to which board? ")
local board = string.upper(io.read())
if board == "" then
do_list()
elseif board_names[board] == nil then
print("No such board! Hit `l` to list boards.")
else
current_board = board
current_board_threads = get_threads(current_board)
end
end
function do_help()
cat_file(path.join(_BBS_ROOT, "docs", "help"))
end
function do_help2()
cat_file(path.join(_BBS_ROOT, "docs", "help2"))
end
function do_list()
update_boards()
for _,b in ipairs(boards) do
local threads = -3 -- Don't want to count "topic" file or "." or ".."
for topic in lfs.dir(path.join(_BBS_ROOT, "boards", b)) do
threads = threads +1
end
print(string.format("%s [%d threads]", b, threads))
end
end
function do_messages()
if not check_at_board() then return end
current_board_threads = get_threads(current_board)
for i, thread in ipairs(current_board_threads) do
print(tostring(i), os.date("%x %H:%M", thread.timestamp), thread.author, thread.subject, "("..tostring(thread.post_count).." posts)")
end
end
function do_new()
if not check_at_board() then return end
-- Get subject for new thread
io.write("Subject? ")
local subject = io.read()
if string.len(subject) > 48 then
print("Thread subjects must be 48 characters or less!")
return
elseif string.len(subject) == 0 then
print("New thread cancelled.")
return
end
-- Save body of post to temp file
local filename = os.tmpname()
os.execute("$EDITOR " .. filename)
-- TODO: show and confirm
-- Make thread dir
local timestamp = tostring(os.time())
local thread_dir = timestamp .. "-" .. username
local thread_path = path.join(_BBS_ROOT, "boards", current_board, thread_dir)
lfs.mkdir(thread_path)
-- Write subject file
file.write(path.join(thread_path, "subject"),
subject)
-- Move post file
local post_file = thread_dir -- first post and thread directory names are the same!
local newpath = path.join(thread_path, post_file)
local ret, str = file.move(filename, newpath)
if not ret then
print(str)
end
-- Done!
print("Post submitted.")
end
-- The "type" command is implemented using multiple functions
-- do_type is the entry point, which runs a command dispatch loop that
-- runs various do_type_xxx functions.
function do_type_first()
current_post_index = 1
do_type_show_post()
end
function do_type_last()
current_post_index = #current_thread_posts
do_type_show_post()
end
function do_type_next()
if current_post_index ~= #current_thread_posts then
current_post_index = current_post_index + 1
end
do_type_show_post()
end
function do_type_prev()
if current_post_index ~= 1 then
current_post_index = current_post_index - 1
end
do_type_show_post()
end
function do_type_reply()
local filename = os.tmpname()
os.execute("$EDITOR " .. filename)
local timestamp = tostring(os.time())
local newfilename = timestamp .. "-" .. username
local newpath = path.join(current_thread.directory, newfilename)
local ret, str = file.move(filename, newpath)
if not ret then
print(str)
end
current_thread_posts = get_posts(current_thread)
current_post_index = #current_thread_posts
do_type_show_post()
end
function do_type_show_post()
local post = current_thread_posts[current_post_index]
print("SUBJECT: " .. current_thread.subject)
print("AUTHOR: " .. post.author)
print("POSTED: " .. os.date("%H:%M %B %d, %Y", post.timestamp))
print("--------------------------------")
cat_file(post.filename)
print("--------------------------------")
print(string.format("Viewing post %d of %d in thread", current_post_index, #current_thread_posts))
end
type_dispatch = {}
type_dispatch["f"] = do_type_first
type_dispatch["l"] = do_type_last
type_dispatch["n"] = do_type_next
type_dispatch["p"] = do_type_prev
type_dispatch["r"] = do_type_reply
type_dispatch["d"] = function() return end
function do_type()
if not check_at_board() then return end
io.write("Read which thread? ")
local thread_id = tonumber(io.read())
if not thread_id or thread_id < 0 or thread_id > #current_board_threads then
print("Invalid thread index!")
return
end
current_thread = current_board_threads[thread_id]
current_thread_posts = get_posts(current_thread)
current_post_index = #current_thread_posts
do_type_show_post()
dispatch_loop(type_dispatch, "d",
function() return "[f]irst, [n]ext, [p]rev, [l]last, [r]eply, [d]one > " end,
"Unrecognised command!")
end
-- end of "type" command implementation
function do_quit()
print("Goodbye!")
end
function do_reply()
if not check_at_board() then return end
io.write("Reply to which thread? ")
local thread_id = tonumber(io.read())
if not thread_id or thread_id < 0 or thread_id > #current_board_threads then
print("Invalid thread index!")
return
end
current_thread = current_board_threads[thread_id]
current_thread_posts = get_posts(current_thread)
current_post_index = #current_thread_posts
do_type_reply()
end
function do_rules()
cat_file(path.join(_BBS_ROOT, "docs", "rules"))
end
function do_unimplemented()
print("Sorry, this command is not (yet) implemented!")
end
function do_who()
os.execute("/usr/bin/w")
end
-- MAIN PROGRAM BODY BELOW
-- Show welcome message
print("::::::::::: This is telem ver."..telemver.." :::::::::::")
cat_file(path.join(_BBS_ROOT, "docs", "welcome"))
-- Initialise global vars representing BBS state
update_boards()
-- Build dispatch table mapping chars to functions
dispatch = {}
dispatch["h"] = do_help
dispatch["g"] = do_go
dispatch["l"] = do_list
dispatch["m"] = do_messages
dispatch["q"] = do_quit
dispatch["t"] = do_type
dispatch["?"] = do_help2
dispatch["!"] = do_rules
dispatch["w"] = do_who
dispatch["s"] = do_unimplemented
dispatch["="] = do_unimplemented
dispatch["M"] = do_unimplemented
dispatch["n"] = do_new
dispatch["r"] = do_reply
dispatch["b"] = do_board
dispatch["c"] = do_unimplemented
-- Infinite loop of command dispatch
dispatch_loop(dispatch, "q",
function() return "["..current_board.."] COMMAND :> " end,
"Unrecognised command, hit `h` for help.")
