#include "models.h"

#include "llama-memory-recurrent.h"

llm_build_qwen3next::llm_build_qwen3next(const llama_model & model, const llm_graph_params & params) :

    llm_build_delta_net_base(params), model(model) {

    ggml_tensor * cur;

    ggml_tensor * inpL;

    inpL = build_inp_embd(model.tok_embd);

    cb(inpL, "model.embed_tokens", -1);

    auto * inp = build_inp_mem_hybrid();

    ggml_tensor * inp_pos     = build_inp_pos();

    ggml_tensor * inp_out_ids = build_inp_out_ids();

    for (int il = 0; il < n_layer; ++il) {

        ggml_tensor * inpSA = inpL;

        cur = build_norm(inpL, model.layers[il].attn_norm, nullptr, LLM_NORM_RMS, il);

        cb(cur, "attn_norm", il);

        ggml_build_forward_expand(gf, cur);

        // Determine layer type and build appropriate attention mechanism

        if (hparams.is_recurrent(il)) {

            // Linear attention layer (gated delta net)

            cur = build_layer_attn_linear(inp->get_recr(), cur, il);

        } else {

            // Full attention layer

            cur = build_layer_attn(inp->get_attn(), cur, inp_pos, il);

        }

        if (il == n_layer - 1 && inp_out_ids) {

            cur   = ggml_get_rows(ctx0, cur, inp_out_ids);

            inpSA = ggml_get_rows(ctx0, inpSA, inp_out_ids);

        }

        // Residual connection

        cur = ggml_add(ctx0, cur, inpSA);

        cb(cur, "attn_residual", il);

        // Save the tensor before post-attention norm for residual connection

        ggml_tensor * ffn_residual = cur;

        // Post-attention norm

        ggml_tensor * attn_post_norm = build_norm(cur, model.layers[il].attn_post_norm, nullptr, LLM_NORM_RMS, il);

        cb(attn_post_norm, "attn_post_norm", il);

        // FFN layer (MoE or dense) - without residual connection

        cur = build_layer_ffn(attn_post_norm, il);

        cb(cur, "ffn_out", il);

        // Residual connection for FFN - add to the tensor from before post_attention_layernorm

        cur = ggml_add(ctx0, cur, ffn_residual);

        cb(cur, "post_moe", il);

        // Input for next layer

        inpL = cur;

    }

    cur = inpL;

    // Final norm

    cur = build_norm(cur, model.output_norm, nullptr, LLM_NORM_RMS, -1);

    cb(cur, "result_norm", -1);

    res->t_embd = cur;

    // LM head

    cur = build_lora_mm(model.output, cur);

    cb(cur, "result_output", -1);

    res->t_logits = cur;

    ggml_build_forward_expand(gf, cur);

}

// utility to get one slice from the third dimension

// input dim:  [x, y, c, b]

// output dim: [x, y, 1, b]

static ggml_tensor * get_slice_2d(ggml_context * ctx0, ggml_tensor * t, int64_t c) {

    return ggml_view_4d(ctx0, t, t->ne[0], t->ne[1], 1, t->ne[3],

        t->nb[1], t->nb[2], t->nb[3], t->nb[2] * c);

}

ggml_tensor * llm_build_qwen3next::build_norm_gated(

        ggml_tensor * input,

        ggml_tensor * weights,

        ggml_tensor * gate,

        int           layer) {

    ggml_tensor * normalized = build_norm(input, weights, nullptr, LLM_NORM_RMS, layer);

    ggml_tensor * gated_silu = ggml_silu(ctx0, gate);

    return ggml_mul(ctx0, normalized, gated_silu);

}

ggml_tensor * llm_build_qwen3next::build_layer_attn(

        llm_graph_input_attn_kv * inp,

        ggml_tensor *             cur,

        ggml_tensor *             inp_pos,

        int                       il) {

    const int64_t n_embd_head = hparams.n_embd_head_v;

    GGML_ASSERT(n_embd_head == hparams.n_embd_head_k);

    // Order: joint QG projection, QG split, Q norm, KV projection, K norm, RoPE, attention

    // Qwen3Next uses a single Q projection that outputs query + gate

    ggml_tensor * Qcur_full = build_lora_mm(model.layers[il].wq, cur);

    cb(Qcur_full, "Qcur_full", il);

    Qcur_full = ggml_reshape_4d(ctx0, Qcur_full, n_embd_head * 2, n_head, n_tokens, 1);

    // Split Q projection into query and gate

    // The split should be along dimension 0 (the feature dimension)

    ggml_tensor * Qcur = ggml_view_4d(ctx0, Qcur_full, n_embd_head, n_head, n_tokens, 1,

                                            Qcur_full->nb[1], Qcur_full->nb[2], Qcur_full->nb[3], 0);

    cb(Qcur, "Qcur_view", il);

    ggml_tensor * gate =

        ggml_view_4d(ctx0, Qcur_full, n_embd_head, n_head, n_tokens, 1,

                     Qcur_full->nb[1], Qcur_full->nb[2], Qcur_full->nb[3], n_embd_head * ggml_element_size(Qcur_full));

    cb(gate, "gate", il);

    ggml_tensor * Kcur = build_lora_mm(model.layers[il].wk, cur);

    cb(Kcur, "Kcur", il);

    ggml_tensor * Vcur = build_lora_mm(model.layers[il].wv, cur);

    cb(Vcur, "Vcur", il);

    Kcur = ggml_reshape_3d(ctx0, Kcur, n_embd_head, n_head_kv, n_tokens);

    Vcur = ggml_reshape_3d(ctx0, Vcur, n_embd_head, n_head_kv, n_tokens);

    Qcur = build_norm(Qcur, model.layers[il].attn_q_norm, nullptr, LLM_NORM_RMS, il);

    cb(Qcur, "Qcur_normed", il);

    Kcur = build_norm(Kcur, model.layers[il].attn_k_norm, nullptr, LLM_NORM_RMS, il);

    cb(Kcur, "Kcur_normed", il);

    Qcur = ggml_rope_ext(

            ctx0, Qcur, inp_pos, nullptr,

            n_rot, rope_type, n_ctx_orig, freq_base, freq_scale,

            ext_factor, attn_factor, beta_fast, beta_slow);

    Kcur = ggml_rope_ext(

            ctx0, Kcur, inp_pos, nullptr,

            n_rot, rope_type, n_ctx_orig, freq_base,

            freq_scale, ext_factor, attn_factor, beta_fast, beta_slow);

    cb(Qcur, "Qcur", il);

    cb(Kcur, "Kcur", il);

    cb(Vcur, "Vcur", il);

    const float kq_scale = hparams.f_attention_scale == 0.0f ? 1.0f / sqrtf(float(n_embd_head)) : hparams.f_attention_scale;

    cur = build_attn(inp,

                nullptr, nullptr,

                Qcur, Kcur, Vcur, nullptr, nullptr, nullptr, kq_scale, il);

    cb(cur, "attn_pregate", il);

    // TODO: CUDA is missing non-contiguous unary ops. when implemented: remove this cont

    gate = ggml_cont_2d(ctx0, gate, n_embd_head * n_head, n_tokens);

    gate = ggml_sigmoid(ctx0, gate);

    cb(gate, "gate_sigmoid", il);

    gate = ggml_reshape_2d(ctx0, gate, n_embd_head * n_head, n_tokens);

    cur = ggml_mul(ctx0, cur, gate);

    cb(cur, "attn_gated", il);

    cur = build_lora_mm(model.layers[il].wo, cur);

    cb(cur, "attn_output", il);

    return cur;

}

std::pair<ggml_tensor *, ggml_tensor *> llm_build_qwen3next::build_qkvz(

                ggml_tensor * input,

                        int   il) {

    const int64_t d_inner      = hparams.ssm_d_inner;

    const int64_t n_seqs       = ubatch.n_seqs;

    const int64_t head_k_dim   = hparams.ssm_d_state;

    const int64_t num_k_heads  = hparams.ssm_n_group;

    const int64_t num_v_heads  = hparams.ssm_dt_rank;

    const int64_t head_v_dim   = d_inner / num_v_heads;

    const int64_t n_seq_tokens = ubatch.n_seq_tokens;

    if (model.layers[il].wqkv) {

        // optimized path

        ggml_tensor * qkv_mixed = build_lora_mm(model.layers[il].wqkv, input);

        qkv_mixed = ggml_reshape_3d(ctx0, qkv_mixed, qkv_mixed->ne[0], n_seq_tokens, n_seqs);

        cb(qkv_mixed, "linear_attn_qkv_mixed", il);

        ggml_tensor * z = build_lora_mm(model.layers[il].wqkv_gate, input);

        cb(z, "z", il);

        return { qkv_mixed, z };

    } else {

        // legacy (slower) path

        ggml_tensor * mixed_qkvz = build_lora_mm(model.layers[il].ssm_in, input);

        cb(mixed_qkvz, "linear_attn_mixed_qkvz", il);

        int64_t       qkvz_new_dim        = 2 * head_k_dim + 2 * head_v_dim * (num_v_heads / num_k_heads);

        ggml_tensor * mixed_qkvz_reshaped = ggml_reshape_4d(ctx0, mixed_qkvz, qkvz_new_dim, num_k_heads, n_seq_tokens, n_seqs);

        // Split mixed_qkvz into query, key, value, z

        int64_t split_sizes_qkvz[4] = {

            head_k_dim,                              // query size

            head_k_dim,                              // key size

            head_v_dim * num_v_heads / num_k_heads,  // value size

            head_v_dim * num_v_heads / num_k_heads   // z size

        };

        ggml_tensor * query =

            ggml_view_4d(ctx0, mixed_qkvz_reshaped, split_sizes_qkvz[0], num_k_heads, n_seq_tokens, n_seqs,

                        mixed_qkvz_reshaped->nb[1], mixed_qkvz_reshaped->nb[2], mixed_qkvz_reshaped->nb[3], 0);

        cb(query, "q", il);

        ggml_tensor * key = ggml_view_4d(ctx0, mixed_qkvz_reshaped, split_sizes_qkvz[1], num_k_heads, n_seq_tokens, n_seqs,

                                        mixed_qkvz_reshaped->nb[1], mixed_qkvz_reshaped->nb[2], mixed_qkvz_reshaped->nb[3],

                                        split_sizes_qkvz[0] * ggml_element_size(mixed_qkvz_reshaped));

        cb(key, "k", il);

        ggml_tensor * value =

            ggml_view_4d(ctx0, mixed_qkvz_reshaped, split_sizes_qkvz[2], num_k_heads, n_seq_tokens, n_seqs,

                        mixed_qkvz_reshaped->nb[1], mixed_qkvz_reshaped->nb[2], mixed_qkvz_reshaped->nb[3],

                        (split_sizes_qkvz[0] + split_sizes_qkvz[1]) * ggml_element_size(mixed_qkvz_reshaped));

        cb(value, "v", il);

        ggml_tensor * z = ggml_view_4d(ctx0, mixed_qkvz_reshaped, split_sizes_qkvz[3], num_k_heads, n_seq_tokens, n_seqs,

                                    mixed_qkvz_reshaped->nb[1], mixed_qkvz_reshaped->nb[2], mixed_qkvz_reshaped->nb[3],

                                    (split_sizes_qkvz[0] + split_sizes_qkvz[1] + split_sizes_qkvz[2]) * ggml_element_size(mixed_qkvz_reshaped));

        z = ggml_cont(ctx0, z);

        cb(z, "z", il);

        // After creating query, key, and value_reshaped, reshape each to flatten the head dimensions

        // query: [head_k_dim, num_k_heads, n_tokens, n_seqs] -> [head_k_dim * num_k_heads, n_tokens, n_seqs]

        ggml_tensor * query_flat = ggml_cont_3d(ctx0, query, head_k_dim * num_k_heads, n_seq_tokens, n_seqs);

        cb(query_flat, "query_flat", il);

        // key: [head_k_dim, num_k_heads, n_tokens, n_seqs] -> [head_k_dim * num_k_heads, n_tokens, n_seqs]

        ggml_tensor * key_flat = ggml_cont_3d(ctx0, key, head_k_dim * num_k_heads, n_seq_tokens, n_seqs);

        cb(key_flat, "key_flat", il);

        // value_reshaped: [head_v_dim, num_v_heads, n_tokens, n_seqs] -> [head_v_dim * num_v_heads, n_tokens, n_seqs]

        ggml_tensor * value_flat = ggml_cont_3d(ctx0, value, head_v_dim * num_v_heads, n_seq_tokens, n_seqs);

        cb(value_flat, "value_flat", il);

        // Now concatenate along the feature dimension (dim 0) to get [conv_dim, n_tokens, n_seqs]

        ggml_tensor * qkv_mixed = ggml_concat(ctx0, query_flat, key_flat, 0);

        qkv_mixed               = ggml_concat(ctx0, qkv_mixed, value_flat, 0);

        cb(qkv_mixed, "qkv_mixed", il);

        return { qkv_mixed, z };

    }

}

ggml_tensor * llm_build_qwen3next::build_layer_attn_linear(

        llm_graph_input_rs * inp,

        ggml_tensor *        cur,

        int                  il) {

    const auto * mctx_cur = inp->mctx;

    const int64_t d_inner      = hparams.ssm_d_inner;

    const int64_t n_seqs       = ubatch.n_seqs;

    const int64_t head_k_dim   = hparams.ssm_d_state;

    const int64_t num_k_heads  = hparams.ssm_n_group;

    const int64_t num_v_heads  = hparams.ssm_dt_rank;

    const int64_t head_v_dim   = d_inner / num_v_heads;

    const int64_t n_seq_tokens = ubatch.n_seq_tokens;

    const auto kv_head = mctx_cur->get_head();

    GGML_ASSERT(n_seqs != 0);

    GGML_ASSERT(ubatch.equal_seqs());

    GGML_ASSERT(ubatch.n_tokens == n_seq_tokens * n_seqs);

    // Input projections

    auto qkvz = build_qkvz(cur, il);

    ggml_tensor * qkv_mixed = qkvz.first;

    ggml_tensor * z         = qkvz.second;

    ggml_tensor * mixed_ba = build_lora_mm(model.layers[il].ssm_beta_alpha, cur);

    cb(mixed_ba, "linear_attn_mixed_ba", il);

    // Reshape mixed_ba: [batch, seq_len, hidden_size] -> [batch, seq_len, num_k_heads, 2*num_v_heads/num_k_heads]

    int64_t       ba_new_dim        = 2 * num_v_heads / num_k_heads;

    ggml_tensor * mixed_ba_reshaped = ggml_reshape_4d(ctx0, mixed_ba, ba_new_dim, num_k_heads, n_seq_tokens, n_seqs);

    // Split mixed_ba into b and a (beta and alpha parameters)

    int64_t split_sizes_ba[2] = {

        num_v_heads / num_k_heads,  // beta size

        num_v_heads / num_k_heads   // alpha size

    };

    ggml_tensor * b = ggml_view_4d(ctx0, mixed_ba_reshaped, split_sizes_ba[0], num_k_heads, n_seq_tokens, n_seqs,

                                   mixed_ba_reshaped->nb[1], mixed_ba_reshaped->nb[2], mixed_ba_reshaped->nb[3], 0);

    cb(b, "b", il);

    ggml_tensor * a = ggml_view_4d(ctx0, mixed_ba_reshaped, split_sizes_ba[1], num_k_heads, n_seq_tokens, n_seqs,

                                   mixed_ba_reshaped->nb[1], mixed_ba_reshaped->nb[2], mixed_ba_reshaped->nb[3],

                                   split_sizes_ba[0] * ggml_element_size(mixed_ba_reshaped));

    cb(a, "a", il);

    // TODO: CUDA is missing non-contiguous unary ops. when implemented: remove this cont

    b = ggml_cont(ctx0, b);

    ggml_tensor * beta = ggml_sigmoid(ctx0, b);

    // Reshape a to merge head dimensions: [batch, seq_len, num_k_heads, num_v_heads/num_k_heads] -> [batch, seq_len, num_v_heads]

    ggml_tensor * alpha = ggml_cont_3d(ctx0, a, num_v_heads, n_seq_tokens, n_seqs);

    ggml_tensor * alpha_biased   = ggml_add(ctx0, alpha, model.layers[il].ssm_dt);

    ggml_tensor * alpha_softplus = ggml_softplus(ctx0, alpha_biased);

    cb(alpha_softplus, "a_softplus", il);

    ggml_tensor * gate = ggml_mul(ctx0, alpha_softplus, model.layers[il].ssm_a);  // -A_log.exp() * softplus

    cb(gate, "gate", il);

    beta = ggml_reshape_4d(ctx0, beta, 1, num_v_heads, n_seq_tokens, n_seqs);

    gate = ggml_reshape_4d(ctx0, gate, 1, num_v_heads, n_seq_tokens, n_seqs);

    // Get convolution states from cache

    ggml_tensor * conv_states_all = mctx_cur->get_r_l(il);

    ggml_tensor * ssm_states_all  = mctx_cur->get_s_l(il);

    // Build the convolution states tensor

    ggml_tensor * conv_states = build_rs(inp, conv_states_all, hparams.n_embd_r(), n_seqs);

    cb(conv_states, "conv_states", il);

    // Calculate convolution kernel size

    ggml_tensor * conv_kernel      = model.layers[il].ssm_conv1d;

    const int64_t conv_kernel_size = conv_kernel->ne[0];

    const int64_t conv_channels    = d_inner + 2 * hparams.ssm_n_group * hparams.ssm_d_state;

    conv_states = ggml_reshape_3d(ctx0, conv_states, conv_kernel_size - 1, conv_channels, n_seqs);

    cb(conv_states, "conv_states_reshaped", il);

    qkv_mixed = ggml_transpose(ctx0, qkv_mixed);

    cb(qkv_mixed, "qkv_mixed_transposed", il);

    ggml_tensor * conv_input = ggml_concat(ctx0, conv_states, qkv_mixed, 0);

    cb(conv_input, "conv_input", il);

    // Update convolution state cache

    // Extract the last (conv_kernel_size - 1) states from conv_input

    ggml_tensor * last_conv_states =

        ggml_view_3d(ctx0, conv_input, conv_kernel_size - 1, conv_channels, n_seqs, conv_input->nb[1],

                     conv_input->nb[2], (conv_input->ne[0] - conv_states->ne[0]) * ggml_element_size(conv_input));

    cb(last_conv_states, "last_conv_states", il);

    ggml_tensor * state_update_target =

        ggml_view_1d(ctx0, conv_states_all, (conv_kernel_size - 1) * conv_channels * n_seqs,

                     kv_head * (conv_kernel_size - 1) * conv_channels * ggml_element_size(conv_states_all));

    cb(state_update_target, "state_update_target", il);

    ggml_build_forward_expand(gf, ggml_cpy(ctx0, last_conv_states, state_update_target));

    ggml_tensor * state = build_rs(inp, ssm_states_all, hparams.n_embd_s(), n_seqs);

    state = ggml_reshape_4d(ctx0, state, head_v_dim, head_v_dim, num_v_heads, n_seqs);

    cb(state, "state_predelta", il);

    ggml_tensor * conv_output_proper = ggml_ssm_conv(ctx0, conv_input, conv_kernel);

    cb(conv_output_proper, "conv_output_raw", il);

    ggml_tensor * conv_output_silu = ggml_silu(ctx0, conv_output_proper);

    cb(conv_output_silu, "conv_output_silu", il);

    ggml_tensor * conv_qkv_mix = conv_output_silu;

    // Calculate the total conv dimension

    int64_t qkv_dim = head_k_dim * num_k_heads * 2 + head_v_dim * num_v_heads;

    int64_t nb1_qkv = ggml_row_size(conv_qkv_mix->type, qkv_dim);

    // Extract the convolved Q, K, V from conv_output

    ggml_tensor * q_conv = ggml_view_4d(ctx0, conv_qkv_mix, head_k_dim, num_k_heads, n_seq_tokens, n_seqs,

            ggml_row_size(conv_qkv_mix->type, head_k_dim),

            nb1_qkv,

            nb1_qkv * n_seq_tokens,

            0);

    ggml_tensor * k_conv = ggml_view_4d(ctx0, conv_qkv_mix, head_k_dim, num_k_heads, n_seq_tokens, n_seqs,

            ggml_row_size(conv_qkv_mix->type, head_k_dim),

            nb1_qkv,

            nb1_qkv * n_seq_tokens,

            head_k_dim * num_k_heads * ggml_element_size(conv_qkv_mix));

    ggml_tensor * v_conv = ggml_view_4d(ctx0, conv_qkv_mix, head_v_dim, num_v_heads, n_seq_tokens, n_seqs,

            ggml_row_size(conv_qkv_mix->type, head_v_dim),

            nb1_qkv,

            nb1_qkv * n_seq_tokens,

            ggml_row_size(conv_qkv_mix->type, 2 * head_k_dim * num_k_heads));

    cb(q_conv, "q_conv", il);

    cb(k_conv, "k_conv", il);

    cb(v_conv, "v_conv", il);

    const float eps_norm = hparams.f_norm_rms_eps;

    q_conv = ggml_l2_norm(ctx0, q_conv, eps_norm);

    k_conv = ggml_l2_norm(ctx0, k_conv, eps_norm);

    //q_conv = ggml_cont_4d(ctx0, q_conv, head_k_dim, num_k_heads, n_seq_tokens, n_seqs);

    //k_conv = ggml_cont_4d(ctx0, k_conv, head_k_dim, num_k_heads, n_seq_tokens, n_seqs);

    //v_conv = ggml_cont_4d(ctx0, v_conv, head_v_dim, num_v_heads, n_seq_tokens, n_seqs);

    // if head keys and value keys are different, repeat to force tensors into matching shapes

    if (num_k_heads != num_v_heads) {

        GGML_ASSERT(num_v_heads % num_k_heads == 0);

        int64_t repeat_factor = num_v_heads / num_k_heads;

        // repeat interleave: reshape to (repeat part, 1, remaining part), do repeat, then reshape back

        ggml_tensor * q_reshaped = ggml_reshape_3d(ctx0, q_conv, head_k_dim, 1, num_k_heads * n_seq_tokens * n_seqs);

        ggml_tensor * k_reshaped = ggml_reshape_3d(ctx0, k_conv, head_k_dim, 1, num_k_heads * n_seq_tokens * n_seqs);

        // Repeat along the third dimension (the new dimension with size 1)

        ggml_tensor * q_repeated =

            ggml_repeat_4d(ctx0, q_reshaped, head_k_dim, repeat_factor, num_k_heads * n_seq_tokens * n_seqs, 1);

        ggml_tensor * k_repeated =

            ggml_repeat_4d(ctx0, k_reshaped, head_k_dim, repeat_factor, num_k_heads * n_seq_tokens * n_seqs, 1);

        // Reshape back to merge the head and repeat dimensions

        // From [head_dim, num_k_heads, repeat_factor, n_seq_tokens * n_seqs]

        // Back to [head_dim, num_k_heads * repeat_factor, n_seq_tokens, n_seqs]

        q_conv = ggml_reshape_4d(ctx0, q_repeated, head_k_dim, num_k_heads * repeat_factor, n_seq_tokens, n_seqs);

        k_conv = ggml_reshape_4d(ctx0, k_repeated, head_k_dim, num_k_heads * repeat_factor, n_seq_tokens, n_seqs);

    }

    cb(q_conv, "q_conv_predelta", il);

    cb(k_conv, "k_conv_predelta", il);

    cb(v_conv, "v_conv_predelta", il);

    // Choose between build_delta_net_chunking, build_delta_net_recurrent, and build_delta_net_autoregressive based on n_tokens

    std::pair<ggml_tensor *, ggml_tensor *> attn_out; // pair of (output, new_state)

    if (n_seq_tokens == 1) {

        attn_out = build_delta_net_autoregressive(q_conv, k_conv, v_conv, gate, beta, state, il);

    } else {

        attn_out = build_delta_net_chunking(q_conv, k_conv, v_conv, gate, beta, state, il);

    }

    ggml_tensor * output    = attn_out.first;

    ggml_tensor * new_state = attn_out.second;

    cb(output, "attn_output", il);

    cb(new_state, "new_state", il);

    // Update the recurrent states

    ggml_build_forward_expand(gf,

            ggml_cpy(ctx0, new_state,

                ggml_view_1d(ctx0, ssm_states_all, hparams.n_embd_s() * n_seqs,

                    kv_head * hparams.n_embd_s() * ggml_element_size(ssm_states_all))));

    // z: [head_dim, n_heads, n_tokens, n_seqs] -> [n_heads * n_tokens * n_seqs, head_dim]

    ggml_tensor * z_2d = ggml_reshape_4d(ctx0, z, head_v_dim, num_v_heads, n_seq_tokens, n_seqs);

    // Apply gated normalization: self.norm(core_attn_out, z)

    ggml_tensor * attn_out_norm = build_norm_gated(output, model.layers[il].ssm_norm, z_2d, il);

    // Final reshape: [head_dim, n_heads, n_tokens, n_seqs] -> [n_tokens, n_seqs, n_heads * head_dim]

    ggml_tensor * final_output = ggml_reshape_3d(ctx0, attn_out_norm, head_v_dim * num_v_heads, n_seq_tokens, n_seqs);

    cb(final_output, "final_output", il);

    // Output projection

    cur = build_lora_mm(model.layers[il].ssm_out, final_output);

    cb(cur, "linear_attn_out", il);

    // Reshape back to original dimensions

    cur = ggml_reshape_2d(ctx0, cur, n_embd, n_seq_tokens * n_seqs);

    return cur;

}

ggml_tensor * llm_build_qwen3next::build_layer_ffn(ggml_tensor * cur, const int il) {

    // Check if this is an MoE layer

    if (model.layers[il].ffn_gate_inp != nullptr) {

        // MoE branch

        ggml_tensor * moe_out =

            build_moe_ffn(cur,

                model.layers[il].ffn_gate_inp, model.layers[il].ffn_up_exps,

                model.layers[il].ffn_gate_exps, model.layers[il].ffn_down_exps,

                nullptr,

                n_expert, n_expert_used, LLM_FFN_SILU,

                true, false, 0.0, LLAMA_EXPERT_GATING_FUNC_TYPE_SOFTMAX, il,

                nullptr, model.layers[il].ffn_gate_up_exps);

        cb(moe_out, "ffn_moe_out", il);

        // Add shared experts if present - following Qwen3Next reference implementation

        if (model.layers[il].ffn_up_shexp != nullptr) {

            ggml_tensor * ffn_shexp =

                build_ffn(cur,

                    model.layers[il].ffn_up_shexp,   NULL, NULL,

                    model.layers[il].ffn_gate_shexp, NULL, NULL,

                    model.layers[il].ffn_down_shexp, NULL, NULL,

                    NULL,

                    LLM_FFN_SILU, LLM_FFN_PAR, il);

            cb(ffn_shexp, "ffn_shexp", il);

            // Apply shared expert gating as in the reference implementation

            // The shared expert has its own gate that is sigmoided

            // Note: ffn_gate_inp_shexp is the shared expert gate (outputs 1 value per token)

            ggml_tensor * shared_gate = build_lora_mm(model.layers[il].ffn_gate_inp_shexp, cur);

            cb(shared_gate, "shared_expert_gate", il);

            shared_gate = ggml_sigmoid(ctx0, shared_gate);

            cb(shared_gate, "shared_expert_gate_sigmoid", il);

            ffn_shexp = ggml_mul(ctx0, ffn_shexp, shared_gate);

            cb(ffn_shexp, "ffn_shexp_gated", il);

            cur = ggml_add(ctx0, moe_out, ffn_shexp);

            cb(cur, "ffn_out", il);

        } else {

            cur = moe_out;

        }

    } else {

        // Dense FFN branch (not currently used I believe)

        cur = build_ffn(cur,

            model.layers[il].ffn_up, NULL, NULL,

            model.layers[il].ffn_gate, NULL, NULL,

            model.layers[il].ffn_down, NULL, NULL,

            NULL,

            LLM_FFN_SILU, LLM_FFN_PAR, il);

        cb(cur, "ffn_out", il);

    }

    return cur;

}