kernel/resolution/

identity.rs

//! The identity and bid foundation types: what `Identification::identify`
//! produces about a model ([`IdentifiedModel`]) and what a runtime adapter
//! offers to serve it ([`RuntimeBid`]). The `identify` orchestration and the bid
//! auction build on these.

use std::path::{Path, PathBuf};

use crate::discovery::gguf_models::is_mmproj_name;
use crate::discovery::modality_hints::{Hint, from_config_json};
use crate::discovery::weights::{gguf_tree, primary_of};
use crate::records::{
    Capability, ExecutionMode, JsonValue, Modality, ModelRecord, ParamSpec, ParamType, RunTier,
    RuntimeId, SourceKind,
};
use crate::resolution::format::ModelFormat;
use crate::resolution::format::{gguf_architecture_profile, ollama_profile};
use crate::resolution::gguf::{gguf_facts, has_ggml_magic, has_gguf_magic};
use crate::resolution::pipelines::{
    PipelineFamilyRegistry, SchedulerFacts, diffusers_pipeline_class,
};
use crate::resolution::safetensors::safetensors_format;

/// What identification determined about a model: its format and the modality,
/// capabilities, execution shape, parameter schema, and context/template facts
/// implied by it.
#[derive(Debug, Clone, PartialEq)]
pub struct IdentifiedModel {
    /// The recognized format.
    pub format: ModelFormat,
    /// The modality, if determined.
    pub modality: Option<Modality>,
    /// The capabilities the model can serve.
    pub capabilities: Vec<Capability>,
    /// How the model executes.
    pub execution: ExecutionMode,
    /// The parameter schema for the model.
    pub params: Vec<ParamSpec>,
    /// The diffusers pipeline class, if any.
    pub pipeline_class: Option<String>,
    /// A context-window hint.
    pub context_length: Option<i64>,
    /// Whether the model ships a chat template.
    pub has_chat_template: Option<bool>,
}

impl IdentifiedModel {
    /// An identification with just the core fields; the rest default to empty.
    pub fn new(
        format: ModelFormat,
        modality: Option<Modality>,
        capabilities: Vec<Capability>,
        execution: ExecutionMode,
    ) -> Self {
        Self {
            format,
            modality,
            capabilities,
            execution,
            params: Vec::new(),
            pipeline_class: None,
            context_length: None,
            has_chat_template: None,
        }
    }
}

/// A runtime adapter's offer to serve a model: how well it runs (the tier), a
/// ranking preference (lower wins), and the other runtimes that could also serve
/// it (recorded as alternatives on the resolved record).
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct RuntimeBid {
    /// How the runtime would run the model.
    pub tier: RunTier,
    /// The ranking preference: a lower value wins. The `tier` is not part of the
    /// ordering (it is recorded on the winner, not compared).
    pub preference: i64,
    /// Other runtimes that could serve the model.
    pub alternatives: Vec<RuntimeId>,
}

impl RuntimeBid {
    /// A bid at `tier`/`preference` with no alternatives.
    pub fn new(tier: RunTier, preference: i64) -> Self {
        Self {
            tier,
            preference,
            alternatives: Vec::new(),
        }
    }

    /// A bid carrying the runtimes that could also serve the model.
    pub fn with_alternatives(tier: RunTier, preference: i64, alternatives: Vec<RuntimeId>) -> Self {
        Self {
            tier,
            preference,
            alternatives,
        }
    }
}

/// Identify what a `record` is from its source kind and on-disk files: a fixed
/// profile for builtin/endpoint/ollama models, else the GGUF/GGML header, a
/// diffusers `model_index.json`, a `config.json`+safetensors layout, or the
/// GGUF weights inside the container when the record names a directory, which
/// is the shape a Hugging Face cache repo has.
///
/// `record.source.path` is taken as-is (callers pass an absolute path — discovery
/// does); a leading `~` is not expanded.
pub fn identify(record: &ModelRecord) -> IdentifiedModel {
    let kind = &record.source.kind;
    if *kind == SourceKind::builtin() {
        return chat_model(ModelFormat::Builtin, builtin_params());
    }
    if *kind == SourceKind::endpoint() {
        return chat_model(ModelFormat::Endpoint, endpoint_params());
    }
    if *kind == SourceKind::ollama() {
        let profile = ollama_profile(
            manifest_has_projector_layer(&record.source.path),
            record.primary_weight_path.as_deref(),
        );
        return IdentifiedModel::new(
            ModelFormat::OllamaStore,
            Some(profile.modality),
            profile.capabilities,
            profile.execution,
        );
    }

    let base = Path::new(&record.source.path);
    let container = container_url(base, record);
    let extension = base
        .extension()
        .and_then(|ext| ext.to_str())
        .map(str::to_ascii_lowercase);

    if extension.as_deref() == Some("bin") && has_ggml_magic(base) {
        return IdentifiedModel::new(
            ModelFormat::GgmlBin,
            Some(Modality::audio()),
            vec![Capability::transcribe()],
            ExecutionMode::Stream,
        );
    }

    if extension.as_deref() == Some("gguf") || has_gguf_magic(base) {
        return identify_gguf(base, has_mmproj_companion(base));
    }

    let model_index = container.join("model_index.json");
    if model_index.exists() {
        return identify_diffusers(&model_index, &container, record);
    }

    let config = container.join("config.json");
    let hint = from_config_json(&config);
    if let Some(format) = safetensors_format(&container, &config) {
        return identify_safetensors(format, hint.as_ref(), &container);
    }
    // A repo whose weights are GGUF names a directory, so the file the header
    // is read from is inside it. Placed after the diffusers and safetensors
    // layouts so a directory that resolves as one keeps doing so, and before
    // the bare config hint below, which it deliberately outranks: a header
    // read from the weights says more than a sibling config file.
    if let Some((weights, has_projector)) =
        gguf_weights(&container, record.primary_weight_path.as_deref())
    {
        return identify_gguf(&weights, has_projector);
    }
    match hint {
        Some(hint) => {
            let mut model = IdentifiedModel::new(
                ModelFormat::Unknown,
                hint.modality,
                hint.capabilities,
                hint.execution,
            );
            model.context_length = hint.context_length;
            model
        }
        None => IdentifiedModel::new(ModelFormat::Unknown, None, Vec::new(), ExecutionMode::Sync),
    }
}

/// The GGUF file a model held in a directory is served from, when it is one,
/// and whether a projector sits with it. Which file that is comes from
/// [`primary_of`], the rule the store scanners pick a primary weight by, so the
/// header read here belongs to the file a server will load. Weights kept in a
/// subdirectory, as a repo with one folder per quantization keeps them, are
/// reached the same way, and so is a projector left at the root beside them.
///
/// The file is named through the container rather than through `primary`,
/// which a Hugging Face record resolves to a blob whose name carries nothing:
/// the projector checks read both the name and its neighbours.
///
/// `primary` refuses the whole container when it is not itself a GGUF, missing
/// included: of the formats this branch can answer, what the runtime would
/// load has the last word.
///
/// An architecture [`gguf_architecture_profile`] does not know reads as a text
/// chat model, which is the answer the same bytes get as a loose file.
fn gguf_weights(container: &Path, primary: Option<&str>) -> Option<(PathBuf, bool)> {
    if let Some(primary) = primary
        && !has_gguf_magic(Path::new(primary))
    {
        return None;
    }
    let tree = gguf_tree(container);
    let weights = primary_of(&tree.weights)?;
    Some((weights, tree.has_projector))
}

/// What a GGUF is, from its header. `has_projector` says whether a multimodal
/// projector accompanies it, which is what makes sight real: an architecture
/// that can see cannot without one.
fn identify_gguf(base: &Path, has_projector: bool) -> IdentifiedModel {
    let name = base
        .file_name()
        .and_then(|name| name.to_str())
        .unwrap_or_default();
    if is_mmproj_name(name) {
        // A CLIP/mmproj projector: vision-only, no directly-served capability.
        return IdentifiedModel::new(
            ModelFormat::Gguf,
            Some(Modality::vision()),
            Vec::new(),
            ExecutionMode::Sync,
        );
    }
    let facts = gguf_facts(base);
    if let Some(architecture) = facts
        .as_ref()
        .and_then(|facts| facts.architecture.as_deref())
        && let Some(profile) = gguf_architecture_profile(architecture)
    {
        let mut capabilities = profile.capabilities;
        if !has_projector {
            // The architecture can see, but no image encoder came with these
            // weights, so nothing here can read a picture. Sight is the
            // pairing, not the architecture.
            capabilities.retain(|capability| *capability != Capability::see());
        }
        let mut model = IdentifiedModel::new(
            ModelFormat::Gguf,
            Some(profile.modality),
            capabilities,
            profile.execution,
        );
        model.context_length = facts.as_ref().and_then(|facts| facts.context_length);
        model.has_chat_template = facts.as_ref().map(|facts| facts.has_chat_template);
        return model;
    }
    let capabilities = if has_projector {
        vec![
            Capability::chat(),
            Capability::complete(),
            Capability::see(),
        ]
    } else {
        vec![Capability::chat(), Capability::complete()]
    };
    let mut model = IdentifiedModel::new(
        ModelFormat::Gguf,
        Some(Modality::text()),
        capabilities,
        ExecutionMode::Stream,
    );
    model.context_length = facts.as_ref().and_then(|facts| facts.context_length);
    model.has_chat_template = facts.as_ref().map(|facts| facts.has_chat_template);
    model
}

fn identify_safetensors(
    format: ModelFormat,
    hint: Option<&Hint>,
    container: &Path,
) -> IdentifiedModel {
    let hint_modality = hint.and_then(|hint| hint.modality.clone());
    let text = Some(Modality::text());
    if (hint_modality.is_none() || hint_modality == text)
        && has_sentence_transformers_layout(container)
    {
        let mut model = IdentifiedModel::new(
            format,
            Some(Modality::embedding()),
            vec![Capability::embed()],
            ExecutionMode::Stream,
        );
        model.context_length = hint.and_then(|hint| hint.context_length);
        return model;
    }
    let mut model = IdentifiedModel::new(
        format,
        hint.and_then(|hint| hint.modality.clone()),
        hint.map(|hint| hint.capabilities.clone())
            .unwrap_or_default(),
        hint.map_or(ExecutionMode::Sync, |hint| hint.execution),
    );
    model.context_length = hint.and_then(|hint| hint.context_length);
    model
}

fn chat_model(format: ModelFormat, params: Vec<ParamSpec>) -> IdentifiedModel {
    let mut model = IdentifiedModel::new(
        format,
        Some(Modality::text()),
        vec![Capability::chat(), Capability::complete()],
        ExecutionMode::Stream,
    );
    model.params = params;
    model
}

/// The snapshot directory for a Hugging Face cache record (its `ref` under
/// `snapshots/`, if present), else the base path itself.
fn container_url(base: &Path, record: &ModelRecord) -> PathBuf {
    if record.source.kind == SourceKind::huggingface_cache()
        && let Some(reference) = &record.source.reference
    {
        let snapshot = base.join("snapshots").join(reference);
        if snapshot.exists() {
            return snapshot;
        }
    }
    base.to_path_buf()
}

/// Whether an Ollama manifest at `path` declares a `.projector` (vision) layer.
fn manifest_has_projector_layer(path: &str) -> bool {
    let Ok(bytes) = std::fs::read(path) else {
        return false;
    };
    let Ok(JsonValue::Object(object)) = serde_json::from_slice::<JsonValue>(&bytes) else {
        return false;
    };
    let Some(JsonValue::Array(layers)) = object.get("layers") else {
        return false;
    };
    layers.iter().any(|layer| {
        layer
            .as_object()
            .and_then(|fields| fields.get("mediaType"))
            .and_then(JsonValue::as_str)
            .is_some_and(|media| media.ends_with(".projector"))
    })
}

/// Whether a sibling `mmproj` GGUF (a vision projector) sits beside `base`.
fn has_mmproj_companion(base: &Path) -> bool {
    let Some(directory) = base.parent() else {
        return false;
    };
    let base_name = base.file_name().and_then(|name| name.to_str());
    let Ok(entries) = std::fs::read_dir(directory) else {
        return false;
    };
    entries.flatten().any(|entry| {
        let path = entry.path();
        let name = path.file_name().and_then(|name| name.to_str());
        name != base_name
            // Skip hidden files.
            && name.is_some_and(|name| !name.starts_with('.') && is_mmproj_name(name))
            && path
                .extension()
                .and_then(|ext| ext.to_str())
                .is_some_and(|ext| ext.eq_ignore_ascii_case("gguf"))
    })
}

fn has_sentence_transformers_layout(container: &Path) -> bool {
    const MARKERS: [&str; 2] = ["config_sentence_transformers.json", "1_Pooling"];
    let Ok(entries) = std::fs::read_dir(container) else {
        return false;
    };
    entries.flatten().any(|entry| {
        entry
            .file_name()
            .to_str()
            .is_some_and(|name| MARKERS.contains(&name))
    })
}

/// Identify a diffusers bundle from its `model_index.json` and the pipeline-family
/// registry: the `_class_name` selects a family whose modality/capabilities/params
/// (refined by the scheduler + repo name) become the identification. An unknown or
/// absent class falls back to a bare `Diffusers` job carrying just the class name.
fn identify_diffusers(
    model_index: &Path,
    container: &Path,
    record: &ModelRecord,
) -> IdentifiedModel {
    let pipeline_class = diffusers_pipeline_class(model_index);
    let scheduler = scheduler_facts(container);
    let repo_hint = record.source.repo.as_deref().unwrap_or(&record.name);
    let profile = pipeline_class.as_deref().and_then(|class| {
        PipelineFamilyRegistry::shared().profile(class, scheduler.as_ref(), Some(repo_hint))
    });
    let Some(profile) = profile else {
        let mut model =
            IdentifiedModel::new(ModelFormat::Diffusers, None, Vec::new(), ExecutionMode::Job);
        model.pipeline_class = pipeline_class;
        return model;
    };
    let mut params = profile.params;
    // FLUX schnell/dev differ: a distilled model that ignores guidance drops the
    // guidance parameter entirely rather than exposing a dead knob.
    if pipeline_class.as_deref() == Some("FluxPipeline") && !flux_uses_guidance(container) {
        params.retain(|spec| spec.key != "guidance");
    }
    let mut model = IdentifiedModel::new(
        ModelFormat::Diffusers,
        Some(profile.modality),
        profile.capabilities,
        ExecutionMode::Job,
    );
    model.params = params;
    model.pipeline_class = pipeline_class;
    model
}

/// The scheduler facts from `scheduler/scheduler_config.json`, if the file parses.
fn scheduler_facts(container: &Path) -> Option<SchedulerFacts> {
    let path = container.join("scheduler").join("scheduler_config.json");
    let bytes = std::fs::read(path).ok()?;
    let JsonValue::Object(config) = serde_json::from_slice::<JsonValue>(&bytes).ok()? else {
        return None;
    };
    Some(SchedulerFacts::new(
        config
            .get("_class_name")
            .and_then(JsonValue::as_str)
            .map(str::to_owned),
        config
            .get("timestep_spacing")
            .and_then(JsonValue::as_str)
            .map(str::to_owned),
    ))
}

/// Whether a FLUX pipeline's transformer declares `guidance_embeds` (a guidance-
/// distilled model), read from `transformer/config.json`.
fn flux_uses_guidance(container: &Path) -> bool {
    let path = container.join("transformer").join("config.json");
    let Ok(bytes) = std::fs::read(path) else {
        return false;
    };
    let Ok(JsonValue::Object(config)) = serde_json::from_slice::<JsonValue>(&bytes) else {
        return false;
    };
    config
        .get("guidance_embeds")
        .and_then(JsonValue::as_bool)
        .unwrap_or(false)
}

fn param(key: &str, param_type: ParamType, range: Option<Vec<JsonValue>>) -> ParamSpec {
    ParamSpec {
        key: key.to_owned(),
        param_type,
        default_value: None,
        range,
        values: None,
    }
}

fn builtin_params() -> Vec<ParamSpec> {
    vec![
        param(
            "temperature",
            ParamType::Float,
            Some(vec![JsonValue::Double(0.0), JsonValue::Double(2.0)]),
        ),
        param(
            "top_p",
            ParamType::Float,
            Some(vec![JsonValue::Double(0.0), JsonValue::Double(1.0)]),
        ),
        param(
            "top_k",
            ParamType::Int,
            Some(vec![JsonValue::Int(0), JsonValue::Int(100)]),
        ),
        param(
            "max_tokens",
            ParamType::Int,
            Some(vec![JsonValue::Int(1), JsonValue::Int(4096)]),
        ),
        param("seed", ParamType::Int, None),
    ]
}

fn endpoint_params() -> Vec<ParamSpec> {
    vec![
        param(
            "temperature",
            ParamType::Float,
            Some(vec![JsonValue::Double(0.0), JsonValue::Double(2.0)]),
        ),
        param(
            "top_p",
            ParamType::Float,
            Some(vec![JsonValue::Double(0.0), JsonValue::Double(1.0)]),
        ),
        param(
            "max_tokens",
            ParamType::Int,
            Some(vec![JsonValue::Int(1), JsonValue::Int(32768)]),
        ),
        param("stop", ParamType::String, None),
        param("seed", ParamType::Int, None),
        param(
            "frequency_penalty",
            ParamType::Float,
            Some(vec![JsonValue::Double(-2.0), JsonValue::Double(2.0)]),
        ),
        param(
            "presence_penalty",
            ParamType::Float,
            Some(vec![JsonValue::Double(-2.0), JsonValue::Double(2.0)]),
        ),
    ]
}