#include "demo3d_protocol.h"
#include "pxl8_bytes.h"

usize demo3d_protocol_serialize_header(const demo3d_msg_header* msg, u8* buf, usize len) {
    if (len < sizeof(demo3d_msg_header)) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u32_be(&s, msg->sequence);
    pxl8_write_u16_be(&s, msg->size);
    pxl8_write_u8(&s, msg->type);
    pxl8_write_u8(&s, msg->version);
    return s.offset;
}

usize demo3d_protocol_deserialize_header(const u8* buf, usize len, demo3d_msg_header* msg) {
    if (len < sizeof(demo3d_msg_header)) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    msg->sequence = pxl8_read_u32_be(&s);
    msg->size = pxl8_read_u16_be(&s);
    msg->type = pxl8_read_u8(&s);
    msg->version = pxl8_read_u8(&s);
    return s.offset;
}

usize demo3d_protocol_serialize_input(const demo3d_input_msg* msg, u8* buf, usize len) {
    if (len < sizeof(demo3d_input_msg)) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u32_be(&s, msg->buttons);
    pxl8_write_f32_be(&s, msg->look_dx);
    pxl8_write_f32_be(&s, msg->look_dy);
    pxl8_write_f32_be(&s, msg->move_x);
    pxl8_write_f32_be(&s, msg->move_y);
    pxl8_write_f32_be(&s, msg->yaw);
    pxl8_write_u64_be(&s, msg->tick);
    pxl8_write_u64_be(&s, msg->timestamp);
    return s.offset;
}

usize demo3d_protocol_deserialize_input(const u8* buf, usize len, demo3d_input_msg* msg) {
    if (len < sizeof(demo3d_input_msg)) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    msg->buttons = pxl8_read_u32_be(&s);
    msg->look_dx = pxl8_read_f32_be(&s);
    msg->look_dy = pxl8_read_f32_be(&s);
    msg->move_x = pxl8_read_f32_be(&s);
    msg->move_y = pxl8_read_f32_be(&s);
    msg->yaw = pxl8_read_f32_be(&s);
    msg->tick = pxl8_read_u64_be(&s);
    msg->timestamp = pxl8_read_u64_be(&s);
    return s.offset;
}

usize demo3d_protocol_serialize_command(const demo3d_command_msg* msg, u8* buf, usize len) {
    if (len < sizeof(demo3d_command_msg)) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u16_be(&s, msg->cmd_type);
    pxl8_write_bytes(&s, msg->payload, DEMO3D_COMMAND_PAYLOAD_SIZE);
    pxl8_write_u16_be(&s, msg->payload_size);
    pxl8_write_u64_be(&s, msg->tick);
    return s.offset;
}

usize demo3d_protocol_deserialize_command(const u8* buf, usize len, demo3d_command_msg* msg) {
    if (len < sizeof(demo3d_command_msg)) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    msg->cmd_type = pxl8_read_u16_be(&s);
    pxl8_read_bytes(&s, msg->payload, DEMO3D_COMMAND_PAYLOAD_SIZE);
    msg->payload_size = pxl8_read_u16_be(&s);
    msg->tick = pxl8_read_u64_be(&s);
    return s.offset;
}

usize demo3d_protocol_serialize_entity_state(const demo3d_entity_state* state, u8* buf, usize len) {
    if (len < sizeof(demo3d_entity_state)) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u64_be(&s, state->entity_id);
    pxl8_write_bytes(&s, state->userdata, 56);
    return s.offset;
}

usize demo3d_protocol_deserialize_entity_state(const u8* buf, usize len, demo3d_entity_state* state) {
    if (len < sizeof(demo3d_entity_state)) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    state->entity_id = pxl8_read_u64_be(&s);
    pxl8_read_bytes(&s, state->userdata, 56);
    return s.offset;
}

usize demo3d_protocol_serialize_event(const demo3d_event_msg* msg, u8* buf, usize len) {
    if (len < sizeof(demo3d_event_msg)) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u8(&s, msg->event_type);
    pxl8_write_bytes(&s, msg->payload, DEMO3D_EVENT_PAYLOAD_SIZE);
    return s.offset;
}

usize demo3d_protocol_deserialize_event(const u8* buf, usize len, demo3d_event_msg* msg) {
    if (len < sizeof(demo3d_event_msg)) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    msg->event_type = pxl8_read_u8(&s);
    pxl8_read_bytes(&s, msg->payload, DEMO3D_EVENT_PAYLOAD_SIZE);
    return s.offset;
}

usize demo3d_protocol_serialize_snapshot_header(const demo3d_snapshot_header* hdr, u8* buf, usize len) {
    if (len < sizeof(demo3d_snapshot_header)) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u16_be(&s, hdr->entity_count);
    pxl8_write_u16_be(&s, hdr->event_count);
    pxl8_write_u64_be(&s, hdr->player_id);
    pxl8_write_u64_be(&s, hdr->tick);
    pxl8_write_f32_be(&s, hdr->time);
    return s.offset;
}

usize demo3d_protocol_deserialize_snapshot_header(const u8* buf, usize len, demo3d_snapshot_header* hdr) {
    if (len < sizeof(demo3d_snapshot_header)) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    hdr->entity_count = pxl8_read_u16_be(&s);
    hdr->event_count = pxl8_read_u16_be(&s);
    hdr->player_id = pxl8_read_u64_be(&s);
    hdr->tick = pxl8_read_u64_be(&s);
    hdr->time = pxl8_read_f32_be(&s);
    return s.offset;
}

usize demo3d_protocol_serialize_chunk_msg_header(const demo3d_chunk_msg_header* hdr, u8* buf, usize len) {
    if (len < 24) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u8(&s, hdr->chunk_type);
    pxl8_write_u8(&s, hdr->flags);
    pxl8_write_u8(&s, hdr->fragment_idx);
    pxl8_write_u8(&s, hdr->fragment_count);
    pxl8_write_u32_be(&s, hdr->id);
    pxl8_write_u32_be(&s, (u32)hdr->cx);
    pxl8_write_u32_be(&s, (u32)hdr->cy);
    pxl8_write_u32_be(&s, (u32)hdr->cz);
    pxl8_write_u32_be(&s, hdr->version);
    pxl8_write_u16_be(&s, hdr->payload_size);
    pxl8_write_u16_be(&s, hdr->reserved);
    return s.offset;
}

usize demo3d_protocol_deserialize_chunk_msg_header(const u8* buf, usize len, demo3d_chunk_msg_header* hdr) {
    if (len < 24) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    hdr->chunk_type = pxl8_read_u8(&s);
    hdr->flags = pxl8_read_u8(&s);
    hdr->fragment_idx = pxl8_read_u8(&s);
    hdr->fragment_count = pxl8_read_u8(&s);
    hdr->id = pxl8_read_u32_be(&s);
    hdr->cx = (i32)pxl8_read_u32_be(&s);
    hdr->cy = (i32)pxl8_read_u32_be(&s);
    hdr->cz = (i32)pxl8_read_u32_be(&s);
    hdr->version = pxl8_read_u32_be(&s);
    hdr->payload_size = pxl8_read_u16_be(&s);
    hdr->reserved = pxl8_read_u16_be(&s);
    return s.offset;
}

usize demo3d_protocol_deserialize_bsp_wire_header(const u8* buf, usize len, demo3d_bsp_wire_header* hdr) {
    if (len < 48) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    hdr->num_vertices = pxl8_read_u32_be(&s);
    hdr->num_edges = pxl8_read_u32_be(&s);
    hdr->num_faces = pxl8_read_u32_be(&s);
    hdr->num_planes = pxl8_read_u32_be(&s);
    hdr->num_nodes = pxl8_read_u32_be(&s);
    hdr->num_leafs = pxl8_read_u32_be(&s);
    hdr->num_surfedges = pxl8_read_u32_be(&s);
    hdr->num_marksurfaces = pxl8_read_u32_be(&s);
    hdr->num_cell_portals = pxl8_read_u32_be(&s);
    hdr->visdata_size = pxl8_read_u32_be(&s);
    hdr->num_vertex_lights = pxl8_read_u32_be(&s);
    hdr->num_heightfield = pxl8_read_u32_be(&s);
    return s.offset;
}

usize demo3d_protocol_serialize_chunk_enter(const demo3d_chunk_enter_msg* msg, u8* buf, usize len) {
    if (len < 8) return 0;
    pxl8_write_stream s = pxl8_write_stream_create(buf, (u32)len);
    pxl8_write_u32_be(&s, (u32)msg->cx);
    pxl8_write_u32_be(&s, (u32)msg->cz);
    return s.offset;
}

usize demo3d_protocol_deserialize_chunk_enter(const u8* buf, usize len, demo3d_chunk_enter_msg* msg) {
    if (len < 8) return 0;
    pxl8_stream s = pxl8_stream_create(buf, (u32)len);
    msg->cx = (i32)pxl8_read_u32_be(&s);
    msg->cz = (i32)pxl8_read_u32_be(&s);
    return s.offset;
}

u32 demo3d_chunk_hash(i32 cx, i32 cz) {
    u32 h = (u32)cx * 374761393u + (u32)cz * 668265263u;
    return h ^ (h >> 16);
}