#!/usr/bin/env lua
--[[

All-in-one packager for LuaRocks
   * by Hisham Muhammad <hisham@gobolinux.org>
   * licensed under the same terms as Lua (MIT license).

Based on:

* srlua.c - Lua interpreter for self-running programs
   * by Luiz Henrique de Figueiredo <lhf@tecgraf.puc-rio.br>
   * 03 Nov 2014 15:31:43
   * srlua.c is placed in the public domain.
* bin2c.lua - converts a binary to a C string that can be embedded
   * by Mark Edgar
   * http://lua-users.org/wiki/BinTwoCee
   * bin2c.lua is licensed under the same terms as Lua (MIT license).
* lua.c - Lua stand-alone interpreter
   * by Luiz Henrique de Figueiredo, Waldemar Celes, Roberto Ierusalimschy
   * lua.c is licensed under the same terms as Lua (MIT license).
* luastatic - builds a standalone executable from a Lua program
   * by Eric R. Schulz
   * https://github.com/ers35/luastatic
   * luastatic is licensed under the CC0 1.0 Universal license

]]

local MAIN_PROGRAM = arg[1] or "src/bin/luarocks"
local LUA_DIR = arg[2] or "/usr"
local EXCLUDE = arg[3] or "^src/luarocks/admin/"
local SYSCONFDIR = arg[4] or "/etc/luarocks"
local TARGET = arg[5] or "build-binary"
local FORCE_CONFIG = (arg[6] == "yes")
local MY_PLATFORM = arg[7] or "unix"
local CC = arg[8] or "gcc"
local NM = arg[9] or "nm"
local CROSSCOMPILER_SYSROOT = arg[10] or "/usr/lib/mingw-w64-sysroot/i686-w64-mingw32"

local LUA_MODULES = TARGET .. "/lua_modules"
local CONFIG_DIR = TARGET .. "/.luarocks"

package.path = "./src/?.lua;" .. package.path

local fs = require("luarocks.fs")
local cfg = require("luarocks.core.cfg")
local cmd = require("luarocks.cmd")
local deps = require("luarocks.deps")
local path = require("luarocks.path")
local manif = require("luarocks.manif")
local queries = require("luarocks.queries")
local persist = require("luarocks.persist")
local sysdetect = require("luarocks.core.sysdetect")

--------------------------------------------------------------------------------

local function if_platform(plat, val)
   if MY_PLATFORM == plat then
      return val
   end
end

local function reindent_c(input)
   local out = {}
   local indent = 0
   local previous_is_blank = true
   for line in input:gmatch("([^\n]*)") do
      line = line:match("^[ \t]*(.-)[ \t]*$")

      local is_blank = (#line == 0)
      local do_print =
         (not is_blank) or
         (not previous_is_blank and indent == 0)

      if line:match("^[})]") then
         indent = indent - 1
         if indent < 0 then indent = 0 end
      end
      if do_print then
         table.insert(out, string.rep("   ", indent))
         table.insert(out, line)
         table.insert(out, "\n")
      end
      if line:match("[{(]$") then
         indent = indent + 1
      end

      previous_is_blank = is_blank
   end
   return table.concat(out)
end

local hexdump
do
   local numtab = {}
   for i = 0, 255 do
     numtab[string.char(i)] = ("%-3d,"):format(i)
   end
   function hexdump(str)
      return (str:gsub(".", numtab):gsub(("."):rep(80), "%0\n"))
   end
end

local c_preamble = [[

#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

/* portable alerts, from srlua */
#ifdef _WIN32
#include <windows.h>
#define alert(message)  MessageBox(NULL, message, progname, MB_ICONERROR | MB_OK)
#define getprogname()   char name[MAX_PATH]; argv[0]= GetModuleFileName(NULL,name,sizeof(name)) ? name : NULL;
#else
#define alert(message)  fprintf(stderr,"%s: %s\n", progname, message)
#define getprogname()
#endif

static int registry_key;

/* fatal error, from srlua */
static void fatal(const char* message) {
   alert(message);
   exit(EXIT_FAILURE);
}

]]

local function bin2c_file(out, filename)
   local fd = io.open(filename, "rb")
   local content = fd:read("*a"):gsub("^#![^\n]+\n", "")
   fd:close()
   table.insert(out, ("static const unsigned char code[] = {"))
   table.insert(out, hexdump(content))
   table.insert(out, ("};"))
end

local function write_hardcoded_module(dir)

   local system, processor
   if if_platform("unix", true) then
      system, processor = sysdetect.detect()
   else
      system, processor = "windows", "x86"
   end

   local hardcoded = {
      SYSTEM = system,
      PROCESSOR = processor,
      FORCE_CONFIG = FORCE_CONFIG,

      SYSCONFDIR = if_platform("unix", SYSCONFDIR),

      LUA_DIR = if_platform("unix", cfg.variables.LUA_DIR),
      LUA_BINDIR = if_platform("unix", cfg.variables.LUA_BINDIR)
                or if_platform("windows", "."),
      LUA_INTERPRETER = if_platform("unix", cfg.lua_interpreter),
   }
   
   local name = dir .. "/luarocks/core/hardcoded.lua"
   persist.save_as_module(name, hardcoded)
   return name
end

local function declare_modules(out, dirs, skip)
   skip = skip or {}
   table.insert(out, [[
   static void declare_modules(lua_State* L) {
      lua_settop(L, 0);                                /* */
      lua_newtable(L);                                 /* modules */
      lua_pushlightuserdata(L, (void*) &registry_key); /* modules registry_key */
      lua_pushvalue(L, 1);                             /* modules registry_key modules */
      lua_rawset(L, LUA_REGISTRYINDEX);                /* modules */
   ]])
   for _, dir in ipairs(dirs) do
      for _, name in ipairs(fs.find(dir)) do
         local run = true
         for _, pat in ipairs(skip) do
            if name:match(pat) then
               run = false
               break
            end
         end
         if run then
            local filename = dir .. "/" .. name
            if fs.is_file(filename) then
               print(name)
               local modname = name:gsub("%.lua$", ""):gsub("/", ".")
               table.insert(out, ("/* %s */"):format(modname))
               table.insert(out, ("{"))
               bin2c_file(out, filename)
               table.insert(out, ("luaL_loadbuffer(L, code, sizeof(code), %q);"):format(filename))
               table.insert(out, ("lua_setfield(L, 1, %q);"):format(modname))
               table.insert(out, ("}"))
            end
         end
      end
   end
   table.insert(out, [[
      lua_settop(L, 0);                                /* */
   }
   ]])
end

local function nm(filename)
   local pd = io.popen(NM .. " " .. filename)
   local out = pd:read("*a")
   pd:close()
   return out
end

local function declare_libraries(out, dir)
   local a_files = {}
   local externs = {}
   local fn = {}
   table.insert(fn, [[
   static void declare_libraries(lua_State* L) {
      lua_getglobal(L, "package");                     /* package */
      lua_getfield(L, -1, "preload");                  /* package package.preload */
   ]])
   for _, name in ipairs(fs.find(dir)) do
      local filename = dir .. "/" .. name
      if name:match("%.a$") then
         table.insert(a_files, filename)
         local nmout = nm(filename)
         for luaopen in nmout:gmatch("[^dD] _?(luaopen_[%a%p%d]+)") do

            -- FIXME what about module names with underscores?
            local modname = luaopen:gsub("^_?luaopen_", ""):gsub("_", ".")

            table.insert(externs, "extern int " .. luaopen .. "(lua_State* L);")
            table.insert(fn, "lua_pushcfunction(L, " .. luaopen .. ");")
            table.insert(fn, "lua_setfield(L, -2, \"" .. modname .. "\");")
         end
      end
   end
   local pd = io.popen("find " .. dir .. " -name '*.a'", "r")
   for line in pd:lines() do
      table.insert(a_files, line)
   end
   pd:close()
   table.insert(fn, [[
      lua_settop(L, 0);                                /* */
   }
   ]])

   table.insert(out, "\n")
   for _, line in ipairs(externs) do
      table.insert(out, line)
   end
   table.insert(out, "\n")
   for _, line in ipairs(fn) do
      table.insert(out, line)
   end
   table.insert(out, "\n")

   return a_files
end

local function load_main(out, main_program, program_name)
   table.insert(out, [[static void load_main(lua_State* L) {]])
   bin2c_file(out, main_program)
   table.insert(out, ("if(luaL_loadbuffer(L, code, sizeof(code), %q) != LUA_OK) {"):format(program_name))
   table.insert(out, ("   fatal(lua_tostring(L, -1));"))
   table.insert(out, ("}"))
   table.insert(out, [[}]])
   table.insert(out, [[]])
end

local c_main = [[

/* custom package loader */
static int pkg_loader(lua_State* L) {
   lua_pushlightuserdata(L, (void*) &registry_key); /* modname ? registry_key */
   lua_rawget(L, LUA_REGISTRYINDEX);                /* modname ? modules */
   lua_pushvalue(L, -1);                            /* modname ? modules modules */
   lua_pushvalue(L, 1);                             /* modname ? modules modules modname */
   lua_gettable(L, -2);                             /* modname ? modules mod */
   if (lua_type(L, -1) == LUA_TNIL) {
      lua_pop(L, 1);                                /* modname ? modules */
      lua_pushvalue(L, 1);                          /* modname ? modules modname */
      lua_pushliteral(L, ".init");                  /* modname ? modules modname ".init" */
      lua_concat(L, 2);                             /* modname ? modules modname..".init" */
      lua_gettable(L, -2);                          /* modname ? mod */
   }
   return 1;
}

static void install_pkg_loader(lua_State* L) {
   lua_settop(L, 0);                                /* */
   lua_getglobal(L, "table");                       /* table */
   lua_getfield(L, -1, "insert");                   /* table table.insert */
   lua_getglobal(L, "package");                     /* table table.insert package */
   lua_getfield(L, -1, "searchers");                /* table table.insert package package.searchers */
   if (lua_type(L, -1) == LUA_TNIL) {
      lua_pop(L, 1);
      lua_getfield(L, -1, "loaders");               /* table table.insert package package.loaders */
   }
   lua_copy(L, 4, 3);                               /* table table.insert package.searchers */
   lua_settop(L, 3);                                /* table table.insert package.searchers */
   lua_pushnumber(L, 1);                            /* table table.insert package.searchers 1 */
   lua_pushcfunction(L, pkg_loader);                /* table table.insert package.searchers 1 pkg_loader */
   lua_call(L, 3, 0);                               /* table */
   lua_settop(L, 0);                                /* */
}

/* main script launcher, from srlua */
static int pmain(lua_State *L) {
   int argc = lua_tointeger(L, 1);
   char** argv = lua_touserdata(L, 2);
   int i;
   load_main(L);
   lua_createtable(L, argc, 0);
   for (i = 0; i < argc; i++) {
      lua_pushstring(L, argv[i]);
      lua_rawseti(L, -2, i);
   }
   lua_setglobal(L, "arg");
   luaL_checkstack(L, argc - 1, "too many arguments to script");
   for (i = 1; i < argc; i++) {
      lua_pushstring(L, argv[i]);
   }
   lua_call(L, argc - 1, 0);
   return 0;
}

/* error handler, from luac */
static int msghandler (lua_State *L) {
   /* is error object not a string? */
   const char *msg = lua_tostring(L, 1);            
   if (msg == NULL) {
      /* does it have a metamethod that produces a string */
      if (luaL_callmeta(L, 1, "__tostring") && lua_type(L, -1) == LUA_TSTRING) {
         /* then that is the message */
         return 1;
      } else {
         msg = lua_pushfstring(L, "(error object is a %s value)", luaL_typename(L, 1));
      }
   }
   /* append a standard traceback */
   luaL_traceback(L, L, msg, 1);
   return 1;
}

/* main function, from srlua */
int main(int argc, char** argv) {
   lua_State* L;
   getprogname();
   if (argv[0] == NULL) {
      fatal("cannot locate this executable");
   }
   L = luaL_newstate();
   if (L == NULL) {
      fatal("not enough memory for state");
   }
   luaL_openlibs(L);
   install_pkg_loader(L);
   declare_libraries(L);
   declare_modules(L);
   lua_pushcfunction(L, &msghandler);
   lua_pushcfunction(L, &pmain);
   lua_pushinteger(L, argc);
   lua_pushlightuserdata(L, argv);
   if (lua_pcall(L, 2, 0, -4) != 0) {
      fatal(lua_tostring(L, -1));
   }
   lua_close(L);
   return EXIT_SUCCESS;
}

]]

local function filter_in(f, xs)
   for i = #xs, 1, -1 do
      if not f(xs[i]) then
         table.remove(xs, i)
      end
   end
   return xs
end

local function nonnull(x) return x ~= nil end

local function generate(main_program, dir, skip)
   local program_name = main_program:gsub(".*/", "")

   local hardcoded = write_hardcoded_module(dir)
   
   local out = {}
   table.insert(out, ([[static const char* progname = %q;]]):format(program_name))
   table.insert(out, c_preamble)
   load_main(out, main_program, program_name)
   local lua_modules = LUA_MODULES .. "/share/lua/" .. cfg.lua_version
   declare_modules(out, { dir, lua_modules }, skip)
   local a_files = declare_libraries(out, LUA_MODULES .. "/lib/lua/" .. cfg.lua_version)
   table.insert(out, c_main)

   os.remove(hardcoded)
   
   local c_filename = TARGET .. "/" .. program_name .. ".exe.c"
   local fd = io.open(c_filename, "w")
   fd:write(reindent_c(table.concat(out, "\n")))
   fd:close()

   deps.check_lua(cfg.variables)
   
   cmd = table.concat(filter_in(nonnull, {
      CC, "-o", TARGET .. "/" .. program_name .. ".exe",
      "-I", cfg.variables.LUA_INCDIR,
      if_platform("unix", "-rdynamic"),
      "-Os",
      c_filename,
      "-L", cfg.variables.LUA_LIBDIR,
      table.concat(a_files, " "),
      --if_platform("unix", cfg.variables.LUA_LIBDIR .. "/" .. cfg.variables.LUALIB:gsub("%.so.*$", ".a")),
      --if_platform("windows", "mingw/liblua.a"), -- FIXME
      cfg.variables.LUA_LIBDIR .. "/" .. cfg.variables.LUALIB:gsub("%.so.*$", ".a"),
      if_platform("unix", "-ldl"),
      if_platform("unix", "-lpthread"),
      "-lm"
   }), " ")
   print(cmd)
   os.execute(cmd)
end

--------------------------------------------------------------------------------

local function main()

   os.remove("src/luarocks/core/hardcoded.lua")
   cfg.init()
   cfg.variables.LUA_DIR = LUA_DIR
   cfg.variables.LUA_INCDIR = nil -- let it autodetect later
   cfg.variables.LUA_LIBDIR = nil -- let it autodetect later
   fs.init()
   path.use_tree(LUA_MODULES)

   local CONFIG_FILE = CONFIG_DIR .. "/config-" .. cfg.lua_version .. ".lua"
   
   fs.make_dir(CONFIG_DIR)

   persist.save_from_table(CONFIG_FILE, {
      lib_extension = "a",
      external_lib_extension = "a",
      variables = {
         CC = fs.current_dir() .. "/binary/static-gcc",
         LD = fs.current_dir() .. "/binary/static-gcc",
         LIB_EXTENSION = "a",
         LIBFLAG = "-static",
      },
      platforms = if_platform("windows", { "windows", "win32", "mingw32" }),
      external_deps_dirs = if_platform("windows", { CROSSCOMPILER_SYSROOT, fs.current_dir().."/windows-deps" }),
   })
   
   local dependencies = {
      md5 = "md5",
      luasec = "./binary/luasec-0.7alpha-2.rockspec",
      luaposix = if_platform("unix", "./binary/luaposix-34.0.4-1.rockspec"),
      luasocket = "luasocket",
      ["lua-zlib"] = "./binary/lua-zlib-1.2-0.rockspec",
      ["lua-bz2"] = "./binary/lua-bz2-0.1.0-1.rockspec",
      luafilesystem = "luafilesystem",
   }
   
   fs.make_dir(LUA_MODULES)
   for name, arg in pairs(dependencies) do
      print("----------------------------------------------------------------")
      print(name)
      print("----------------------------------------------------------------")
      local vers = manif.get_versions(queries.from_dep_string(name), "one")
      if not next(vers) then
         local ok = os.execute("LUAROCKS_CONFIG='" .. CONFIG_FILE .. "' ./luarocks install '--tree=" .. LUA_MODULES .. "' " .. arg)
         if ok ~= 0 and ok ~= true then
            error("Failed building dependency: " .. name)
         end
      end
   end

   generate(MAIN_PROGRAM, "src", { EXCLUDE, "^bin/?" })
end

main()