jZIP

--[[
    Project info:

    Name: jZip
    Creator: Jesusthekiller
    Language: Lua (CC)
    Website: None
    License: GNU GPL
        License file can be fount at www.jesusthekiller.com/license-gpl.html
    Version: 1.2
]]--

--[[
    Changelog:
      1.0:
        Initial Release
      1.1:
        jZIP API
      1.2:
        jZIP API fix
]]--

--[[
    LICENSE:

    jZip
    Copyright (c) 2013 Jesusthekiller
    This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
    This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>.
]]--

local function usage()
    print("Usage:")
    print("  zip <u|unzip> <zip file>")
    print("  zip <z|zip> <name> <output file> <file 1> [file 2 [...]]")
    print("  zip loadapi")
    print("    It will load zip API - use shell.run('zip', 'loadapi') instead of os.loadAPI('zip').")
end

-- API:
local function decode(text)
    local s = ""
    for k, char in ipairs({ text:byte(1, #text) }) do
        s = s..string.char(char+8)
    end
    return s
end

local function code(text)
    local s = ""
    for k, char in ipairs({ text:byte(1, #text) }) do
        s = s..string.char(char-8)
    end
    return s
end

local oerror = error
local function error(str, mode)
    return oerror("[ZIP API] "..str, mode)
end

local function getDir(path)
    local dir, file, tab = "", "", {}

    for t in path:gmatch("[^/]+") do
        table.insert(tab, t)
    end

    file = table.remove(tab, #tab)

    for k, v in ipairs(tab) do
        dir = dir.."/"..v
    end

    return file, (dir == "") and "/" or dir
end

local function confirm(text)
    print(text)

    local e, k
    repeat
        e, k = os.pullEvent("key")
    until k == keys.y or k == keys.n

    coroutine.yield()

    return (k == keys.y) and true or false
end

local function unzip(file)
    local f = fs.open(file, "r") or error("File '"..file.."' does not exist!", 0)

    -- Read file
    local c = f.readAll()

    -- Close
    f.close()

    -- Split into table and decode
    local t = {}
    for token in decode(c):gmatch("[^\n]+") do
        table.insert(t, token)
    end

    -- Check if it is zip file
    h = table.remove(t, 1)
    if h ~= "`ZIP`" then
        error("File is not ZIP file or it is corrupted", 0)
    end

    -- Print name
    print("Unpacking "..tostring(table.remove(t, 1)))

    -- Loop unpacking process
    while true do
        -- Raw full path
        local rawfullpath = table.remove(t, 1)

        -- Break if end of file
        if not rawfullpath then
            break
        end

        -- Get and print file path
        local fullpath = shell.dir().."/"..rawfullpath
        print("  File "..fullpath)

        -- Resolve path
        local file, dir = getDir(fullpath)

        -- Create dir
        if fs.exists(dir) and not fs.isDir(dir) then
            if not confirm("File "..dir.." exists. Overwrite? [y/n]") then error("This file has to be overwritten to unpack this zip!", 0) end
        end

        if not fs.exists(dir) then
            fs.makeDir(dir)
        end

        -- Open file
        if fs.exists(fullpath) then
            if not confirm("File "..fullpath.." exists. Overwrite? [y/n]") then error("This file has to be overwritten to unpack this zip!", 0) end
            fs.delete(fullpath) -- It it's dir
        end

        local f = fs.open(fullpath, "w")

        -- Unpack file
        local line = table.remove(t, 1)
        while line ~= "`STOP`" and line do
            f.writeLine(line)
            line = table.remove(t, 1)
        end

        f.close()
    end

    print("Done!")
end

local function fileRead(path)
    local f = fs.open(path, "r") or error("Can not open file "..path, 0)
    local s = f.readAll()
    f.close()

    return code(s)
end

local function file(fout, path, out)
    -- Code write func
    local function codeWrite(str)
        fout.write(code(str)..string.char(2))
    end

    if fs.exists(path) then
        if fs.isDir(path) and (not string.find(path, "/rom")) then
            -- Loop trough all dirs
            for k, v in ipairs(fs.list(path)) do
                file(fout, path.."/"..v, out)
            end
        elseif (not string.find(path, "/"..out)) and (not string.find(path, "/rom")) then
            print("  Doing "..path)
            codeWrite(path)
            fout.write(fileRead(path)..string.char(2))
            codeWrite("`STOP`")
            print("    File "..path.." done!")
        else
            print("###WARNING### TRIED TO COMPRESS OUTPUT/BANNED FILE/FOLDER (?) - "..path)
        end
    else
        error("File "..path.." does not exist!", 0)
    end
end

local function fzip(...)
    -- Error checks
    local pars = {...}
    local name = table.remove(pars, 1) or error("No name specified!", 0)
    local out = table.remove(pars, 1) or error("No output file specified!", 0)

    if fs.exists(out) then
        if not confirm("File "..out.." exists. Overwrite? [y/n]") then
            return
        end

        fs.delete(out)
    end

    -- Open out file
    local f = fs.open(out, "w")

    -- Code write func
    local function codeWrite(str)
        f.write(code(str)..string.char(2))
    end

    -- Write headers
    codeWrite("`ZIP`")
    codeWrite(name)

    for k, v in ipairs(pars) do
        local fullpath = shell.dir().."/"..v or error("It should have not happened...", 0)
        if fs.exists(fullpath) then
            file(f, fullpath, out)
        else
            f.close()
            error("File "..fullpath.." does not exist!", 0)
        end
    end
    f.close()

    print("Done!")
end

local args = {...}
args[1] = args[1] or ""
args[1] = args[1]:lower()

if args[1] == "u" or args[1] == "unzip" then
    assert(args[2], "No file specified!")
    unzip(args[2])
elseif args[1] == "z" or args[1] == "zip" then
    table.remove(args, 1)
    fzip(unpack(args))
elseif args[1] == "loadapi" then
    -- Globals
    zip = {}
    zip.zip = fzip
    zip.unzip = unzip
else
    usage()
end