package gluash

import "github.com/yuin/gopher-lua"

var exports = map[string]lua.LGFunction{}
var abort = false
var shouldWait = false
var debug = false

// Loader is used for preloading a module
func Loader(L *lua.LState) int {

	// register functions to the table
	mod := L.SetFuncs(L.NewTable(), exports)

	// set up meta table
	mt := L.NewTable()
	L.SetField(mt, "__index", L.NewClosure(moduleIndex))
	L.SetField(mt, "__call", L.NewClosure(moduleCall))
	L.SetMetatable(mod, mt)

	shMetaTable := L.NewTypeMetatable(luaShTypeName)
	L.SetField(shMetaTable, "__call", L.NewFunction(shCall))
	L.SetField(shMetaTable, "__index", L.NewFunction(shIndex))

	// returns the module
	L.Push(mod)
	return 1
}

// moduleIndex creates and returns userdata shell command (sh) defined by the
// index.
func moduleIndex(L *lua.LState) int {
	index := L.CheckString(2)

	if index == "glob" {
		L.Push(L.NewFunction(glob))
		return 1
	}

	cmd := &shellCommand{
		path: index,
	}

	L.Push(cmd.UserData(L))
	return 1
}

func moduleCall(L *lua.LState) int {
	if L.GetTop() == 2 && L.Get(2).Type() == lua.LTTable {
		return configure(L)
	}

	path := L.CheckString(2)
	args := checkStrings(L, 3)

	cmd, err := newShellCommand(path, args...)
	checkError(L, err)

	err = cmd.Start(shouldWait)
	checkError(L, err)

	L.Push(cmd.UserData(L))
	return 1
}

func glob(L *lua.LState) int {
	pattern := L.CheckString(1)

	args, err := Glob(pattern)
	if err != nil {
		L.RaiseError("%v", err)
	}

	for _, arg := range args {
		L.Push(lua.LString(arg))
	}

	return len(args)
}

func configure(L *lua.LState) int {
	conf := L.CheckTable(2)

	emptyTable := true
	conf.ForEach(func(key, value lua.LValue) {
		emptyTable = false
		switch key.String() {
		case "abort":
			if v, ok := value.(lua.LBool); ok {
				abort = bool(v)
				shouldWait = bool(v)
				return
			}
			L.RaiseError("abort: type error: expected `%v`, got `%v`", lua.LTBool, value.Type())
		case "wait":
			if v, ok := value.(lua.LBool); ok {
				shouldWait = bool(v)
				return
			}
			L.RaiseError("wait: type error: expected `%v`, got `%v`", lua.LTBool, value.Type())
		case "debug":
			if v, ok := value.(lua.LBool); ok {
				debug = bool(v)
				return
			}
			L.RaiseError("debug: type error: expected `%v`, got `%v`", lua.LTBool, value.Type())
		}
	})

	if emptyTable {
		conf.RawSetString("abort", lua.LBool(abort))
		conf.RawSetString("wait", lua.LBool(shouldWait))
		conf.RawSetString("debug", lua.LBool(shouldWait))
		L.Push(conf)
		return 1
	}

	return 0
}