#include "table.hpp"
#include "source.hpp"

LuaDefine(table_equal, "c") {
    LuaArg t1, t2;
    LuaRet eql;
    LuaStack LS(L, t1, t2, eql);
    LS.checktable(t1);
    LS.checktable(t2);
    lua_pushnil(L);
    int total1 = 0;
    while (lua_next(L, t1.index()) != 0) {
        lua_pushvalue(L, -2);   // k v1 k
        lua_rawget(L, t2.index());  // k v1 v2
        if (!lua_equal(L, -1, -2)) {
            LS.set(eql, false);
            return LS.result();
        }
        lua_pop(L, 2);
        total1 += 1;
    }
    int total2 = 0;
    lua_pushnil(L);
    while (lua_next(L, t2.index()) != 0) {
        lua_pop(L, 1);
        total2 += 1;
    }
    LS.set(eql, total1 == total2);
    return LS.result();
}

LuaDefine(table_findremove, "c") {
    luaL_checktype(L, -2, LUA_TTABLE);
    int src = 1;
    int dst = 1;
    while (true) {
        lua_pushinteger(L, src);
        lua_rawget(L, -3);
        if (lua_equal(L, -1, -2)) {
            src++;
            lua_pop(L, 1);
        } else if (lua_isnil(L, -1)) {
            lua_pop(L, 1);
            int removed = src - dst;
            while (src > dst) {
                lua_pushinteger(L, dst);
                lua_pushnil(L);
                lua_rawset(L, -4);
                dst++;
            }
            lua_pop(L, 2);
            lua_pushinteger(L, removed);
            return 1;
        } else {
            if (src > dst) {
                lua_pushinteger(L, dst);
                lua_insert(L, lua_gettop(L) - 1);
                lua_rawset(L, -4);
            } else {
                lua_pop(L, 1);
            }
            src++;
            dst++;
        }
    }
}


LuaDefine(table_push, "c") {
    luaL_checktype(L, -2, LUA_TTABLE);
    int len = lua_objlen(L, -2);
    lua_pushinteger(L, len+1);
    lua_pushvalue(L, -2);
    lua_rawset(L, -4);
    lua_pop(L, 2);
    return 0;
}

LuaDefine(table_find, "c") {
    luaL_checktype(L, -2, LUA_TTABLE);
    for (int i = 1; ; i++) {
        lua_pushinteger(L, i);
        lua_rawget(L, -3);
        if (lua_equal(L, -1, -2)) {
            lua_pop(L, 3);
            lua_pushinteger(L, i);
            return 1;
        } else if (lua_isnil(L, -1)) {
            lua_pop(L, 3);
            lua_pushnil(L);
            return 1;
        } else {
            lua_pop(L, 1);
        }
    }
}

LuaDefine(table_empty, "c") {
    luaL_checktype(L, -1, LUA_TTABLE);
    lua_pushnil(L);
    if (lua_next(L, -2) != 0) {
        lua_pop(L, 3);
        lua_pushboolean(L, 0);
        return 1;
    } else {
        lua_pop(L, 1);
        lua_pushboolean(L, 1);
        return 1;
    }
}

LuaDefine(table_count, "c") {
    luaL_checktype(L, -1, LUA_TTABLE);
    lua_pushnil(L);
    lua_Integer total = 0;
    while (lua_next(L, -2) != 0) {
        total += 1;
        lua_pop(L, 1);
    }
    lua_pop(L, 1);
    lua_pushinteger(L, total);
    return 1;
}

LuaDefine(table_clear, "c") {
    LuaArg tab;
    LuaStack LS(L, tab);
    
    LS.checktable(tab);    
    lua_pushnil(L);
    while (lua_next(L, tab.index()) != 0) {
        lua_pop(L, 1); // Pop the old value.
        lua_pushvalue(L, -1); // Clone the key
        lua_pushnil(L); // Push the new value.
        lua_settable(L, tab.index());
    }
    
    return LS.result();
}

LuaDefine(queue_create, "c") {
    LuaRet queue;
    LuaStack LS(L, queue);

    LS.newtable(queue);
    LS.setfield(queue, "head", 1000000);
    LS.setfield(queue, "tail", 1000000);
    return LS.result();
}

LuaDefine(queue_push, "c") {
    LuaArg queue, elt;
    lua_Integer head;
    LuaStack LS(L, queue, elt);

    LS.getfield(head, queue, "head");
    LS.rawset(queue, head, elt);
    LS.setfield(queue, "head", head+1);
    return LS.result();
}

LuaDefine(queue_pop, "c") {
    LuaArg queue;
    LuaRet elt;
    lua_Integer head, tail;
    LuaStack LS(L, queue, elt);

    LS.getfield(tail, queue, "tail");
    LS.getfield(head, queue, "head");
    if (head == tail) {
        LS.set(elt, LuaNil);
    } else {
        LS.rawget(elt, queue, tail);
        LS.rawset(queue, tail, LuaNil);
        LS.setfield(queue, "tail", tail + 1);
    }
    return LS.result();
}

LuaDefine(queue_size, "c") {
    LuaArg queue;
    LuaRet size;
    lua_Number head, tail;
    LuaStack LS(L, queue, size);

    LS.getfield(head, queue, "head");
    LS.getfield(tail, queue, "tail");
    LS.set(size, head - tail);
    return LS.result();
}

LuaDefine(queue_nth, "c") {
    LuaArg queue, n;
    LuaRet elt;
    lua_Integer nth, head, tail;
    LuaStack LS(L, queue, n, elt);

    nth = LS.ckinteger(n) - 1;
    LS.getfield(head, queue, "head");
    LS.getfield(tail, queue, "tail");
    if ((nth < 0) || (nth + tail >= head)) {
        luaL_error(L, "index out of range");
    }
    LS.rawget(elt, queue, tail + nth);
    return LS.result();
}

LuaDefine(table_getregistry, "f") {
    LuaArg key;
    LuaRet result;
    LuaStack LS(L, key, result);
    LS.rawget(result, LuaRegistry, key);
    return LS.result();
}