bamboo-engine 2026.10.22

// Helper function to extract default model from config
// This should be used instead of hardcoding "gpt-4o-mini" or "default"

use std::sync::Arc;

use crate::config::GoldConfig;
use bamboo_domain::reasoning::ReasoningEffort;
use bamboo_llm::Config;
use bamboo_llm::{LLMError, ProviderRegistry, ResolvedModel};

pub const GOLD_CONFIG_METADATA_KEY: &str = "gold_config";

/// Check the explicit image-description target without constructing a provider.
/// Actual resolution and image dispatch remain exclusive to model-issued ViewImage.
pub fn validate_image_reference_vision_config(
    config: &Config,
    active_provider: &str,
) -> Result<(), String> {
    crate::runtime::runner::image_fallback::validate_configured_vision_target(
        config,
        active_provider,
    )
    .map_err(|error| error.to_string())
}

/// Infer the underlying provider type from a bare model name.
///
/// This is the single, canonical place that maps a model-name string to a
/// provider type. Centralising it here (TD-3) keeps the scattered
/// `claude*`/`gpt*`/`gemini*` pattern matches from drifting apart.
///
/// Mapping:
/// - `claude*` → `anthropic`
/// - `gpt*` or an OpenAI o-series name (`o1`, `o3`, `o4-mini`, ...) → `openai`
/// - `gemini*` → `gemini`
/// - anything else → `None`
///
/// The match is case-insensitive and ignores surrounding whitespace.
pub fn infer_provider(model_name: &str) -> Option<String> {
    let name = model_name.trim().to_ascii_lowercase();
    if name.is_empty() {
        return None;
    }

    if name.starts_with("claude") {
        return Some("anthropic".to_string());
    }
    if name.starts_with("gpt") || is_openai_o_series(&name) {
        return Some("openai".to_string());
    }
    if name.starts_with("gemini") {
        return Some("gemini".to_string());
    }
    None
}

/// Whether a (already lower-cased) model name looks like an OpenAI o-series
/// reasoning model: an `o` immediately followed by a digit (`o1`, `o3-mini`,
/// `o4-mini`, ...).
fn is_openai_o_series(name: &str) -> bool {
    let mut chars = name.chars();
    matches!(chars.next(), Some('o')) && matches!(chars.next(), Some(c) if c.is_ascii_digit())
}

/// Resolve the underlying provider type for a provider routing key.
///
/// In legacy mode the routing key is already the provider type (for example
/// `"openai"` or `"copilot"`). In multi-instance mode the routing key may be an
/// instance id (for example `"copilot-work"`), so we first consult configured
/// provider instances, then the live registry metadata, and finally fall back to
/// the key itself for backward compatibility.
pub fn resolve_provider_type(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<String> {
    let trimmed = provider_name.trim();
    if trimmed.is_empty() {
        return None;
    }

    config
        .provider_instances
        .get(trimmed)
        .map(|instance| instance.provider_type.clone())
        .or_else(|| {
            provider_registry
                .get_metadata(trimmed)
                .map(|meta| meta.provider_type)
        })
        .or_else(|| Some(trimmed.to_string()))
}

/// Resolve an exact runtime routing key from either an instance id or a
/// built-in provider type used by legacy clients/sessions.
///
/// Exact instance ids always win, including disabled or failed instances: in
/// those cases resolution fails closed instead of silently selecting another
/// account. A built-in type selects the enabled default instance of that type,
/// then the lexicographically first enabled instance, matching the model-fetch
/// compatibility contract. The selected instance must exist in the live
/// registry; constructor/auth failures are never replaced by the process-wide
/// default provider.
pub fn resolve_provider_routing_key(
    config: &Config,
    requested_provider: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Result<String, LLMError> {
    let requested = requested_provider.trim();
    if requested.is_empty() {
        return Err(LLMError::Auth("provider routing key is empty".to_string()));
    }

    let require_live = |routing_key: &str| {
        provider_registry
            .get(routing_key)
            .map(|_| routing_key.to_string())
            .ok_or_else(|| {
                LLMError::Auth(format!(
                    "Provider '{routing_key}' is configured but unavailable"
                ))
            })
    };

    if let Some(instance) = config.provider_instances.get(requested) {
        if !instance.enabled {
            return Err(LLMError::Auth(format!(
                "Provider instance '{requested}' is disabled"
            )));
        }
        return require_live(requested);
    }

    // Legacy and hybrid aliases are registered under their exact type key.
    if provider_registry.get(requested).is_some() {
        return Ok(requested.to_string());
    }

    if !bamboo_llm::AVAILABLE_PROVIDERS.contains(&requested) {
        return Err(LLMError::Auth(format!(
            "Unknown provider instance or type '{requested}'"
        )));
    }

    if let Some(default_id) = config.default_provider_instance.as_deref() {
        if let Some(instance) = config.provider_instances.get(default_id) {
            if instance.provider_type == requested {
                if !instance.enabled {
                    return Err(LLMError::Auth(format!(
                        "Default provider instance '{default_id}' is disabled"
                    )));
                }
                return require_live(default_id);
            }
        }
    }

    let mut matching_ids = config
        .provider_instances
        .iter()
        .filter(|(_, instance)| instance.enabled && instance.provider_type == requested)
        .map(|(id, _)| id.as_str())
        .collect::<Vec<_>>();
    matching_ids.sort_unstable();
    if let Some(instance_id) = matching_ids.first() {
        return require_live(instance_id);
    }

    Err(LLMError::Auth(format!(
        "No enabled provider instance is available for type '{requested}'"
    )))
}

pub fn parse_session_gold_config(session_gold_config_json: Option<&str>) -> Option<GoldConfig> {
    let raw = session_gold_config_json?.trim();
    if raw.is_empty() {
        return None;
    }
    serde_json::from_str::<GoldConfig>(raw).ok()
}

pub fn normalize_gold_config_json(value: &serde_json::Value) -> Result<String, serde_json::Error> {
    let parsed = serde_json::from_value::<GoldConfig>(value.clone())?;
    serde_json::to_string(&parsed)
}

pub fn resolve_global_gold_config(config: &Config) -> Option<GoldConfig> {
    config
        .extra
        .get("gold")
        .cloned()
        .and_then(|value| serde_json::from_value::<GoldConfig>(value).ok())
}

pub fn resolve_gold_config(
    config: &Config,
    session_gold_config_json: Option<&str>,
) -> Option<GoldConfig> {
    if session_gold_config_json.is_some() {
        return parse_session_gold_config(session_gold_config_json);
    }
    resolve_global_gold_config(config)
}

/// Get the default model for a specific provider from config.
pub fn get_default_model_for_provider(
    config: &Config,
    provider_name: &str,
) -> Result<String, LLMError> {
    let provider_name = provider_name.trim();
    if let Some(instance) = config.provider_instances.get(provider_name) {
        if !instance.enabled {
            return Err(LLMError::Auth(format!(
                "Provider instance '{provider_name}' is disabled"
            )));
        }
        if let Some(model) = instance
            .model
            .as_deref()
            .map(str::trim)
            .filter(|model| !model.is_empty())
        {
            return Ok(model.to_string());
        }
        if instance.provider_type == "copilot" {
            return Ok("gpt-4o".to_string());
        }
        return Err(LLMError::Auth(format!(
            "Model must be specified for provider instance '{provider_name}'"
        )));
    }

    match provider_name {
        "copilot" => {
            let provider_model = config
                .providers()
                .copilot
                .as_ref()
                .and_then(|c| c.model.clone());

            Ok(provider_model.unwrap_or_else(|| "gpt-4o".to_string()))
        }
        "openai" => {
            let openai_config = config
                .providers()
                .openai
                .as_ref()
                .ok_or_else(|| LLMError::Auth("OpenAI configuration required".to_string()))?;

            openai_config.model.clone().ok_or_else(|| {
                LLMError::Auth("OpenAI model must be specified in config".to_string())
            })
        }
        "anthropic" => {
            let anthropic_config =
                config.providers().anthropic.as_ref().ok_or_else(|| {
                    LLMError::Auth("Anthropic configuration required".to_string())
                })?;

            anthropic_config.model.clone().ok_or_else(|| {
                LLMError::Auth("Anthropic model must be specified in config".to_string())
            })
        }
        "gemini" => {
            let gemini_config = config
                .providers()
                .gemini
                .as_ref()
                .ok_or_else(|| LLMError::Auth("Gemini configuration required".to_string()))?;

            gemini_config.model.clone().ok_or_else(|| {
                LLMError::Auth("Gemini model must be specified in config".to_string())
            })
        }
        other => Err(LLMError::Auth(format!("Unknown provider: {}", other))),
    }
}

/// Get the default model for the current provider from config.
/// Returns an error if no model is configured.
pub fn get_default_model_from_config(config: &Config) -> Result<String, LLMError> {
    get_default_model_for_provider(config, config.effective_default_provider())
}

/// Get the schedule auto-execute model for the current provider from config.
///
/// Falls back from the provider fast model to the default chat model when no
/// dedicated fast model is configured.
pub fn get_schedule_model_from_config(config: &Config) -> Result<String, LLMError> {
    config
        .get_fast_model()
        .map(|model| model.trim().to_string())
        .filter(|model| !model.is_empty())
        .ok_or_else(|| {
            LLMError::Auth(format!(
                "No fast/default model configured for provider '{}'",
                config.effective_default_provider()
            ))
        })
}

/// Get the fast/cheap model for a specific provider from config.
pub fn get_fast_model_for_provider(config: &Config, provider_name: &str) -> Option<String> {
    if let Some(instance) = config.provider_instances.get(provider_name.trim()) {
        if !instance.enabled {
            return None;
        }
        return instance
            .fast_model
            .as_deref()
            .map(str::trim)
            .filter(|model| !model.is_empty())
            .map(ToString::to_string)
            .or_else(|| get_default_model_for_provider(config, provider_name).ok());
    }

    let fast = match provider_name.trim() {
        "openai" => config
            .providers()
            .openai
            .as_ref()
            .and_then(|c| c.fast_model.clone()),
        "anthropic" => config
            .providers()
            .anthropic
            .as_ref()
            .and_then(|c| c.fast_model.clone()),
        "gemini" => config
            .providers()
            .gemini
            .as_ref()
            .and_then(|c| c.fast_model.clone()),
        "copilot" => config
            .providers()
            .copilot
            .as_ref()
            .and_then(|c| c.fast_model.clone()),
        _ => None,
    };

    fast.or_else(|| get_default_model_for_provider(config, provider_name).ok())
}

/// Get the memory/background model for a specific provider from config.
///
/// This uses provider-local fast model fallback and intentionally avoids coupling
/// to the globally active provider.
pub fn get_memory_background_model_for_provider(
    config: &Config,
    provider_name: &str,
) -> Option<String> {
    let configured = config
        .memory()
        .as_ref()
        .and_then(|memory| memory.background_model.as_ref())
        .map(|value| value.trim())
        .filter(|value| !value.is_empty())
        .map(ToString::to_string);

    configured.or_else(|| get_fast_model_for_provider(config, provider_name))
}

/// Get the default reasoning effort for a specific provider routing key.
///
/// `provider_name` is the model_ref's provider, which in multi-instance mode is
/// an instance id (for example `"copilot-work"`). Delegates to
/// [`Config::reasoning_effort_for_key`] so instance ids, the `bodhi` provider,
/// and legacy provider types all resolve consistently with the session-create
/// path.
pub fn get_reasoning_effort_for_provider(
    config: &Config,
    provider_name: &str,
) -> Option<ReasoningEffort> {
    config.reasoning_effort_for_key(provider_name)
}

/// Get the task summarization model for the current provider from config.
///
/// Used for conversation/task summarization and context compression.
pub fn get_task_summary_model_from_config(config: &Config) -> Result<String, LLMError> {
    config.get_task_summary_model().ok_or_else(|| {
        LLMError::Auth(format!(
            "No task summary model configured for provider '{}'",
            config.effective_default_provider()
        ))
    })
}

/// Get the memory/background summarization model for the current provider from config.
///
/// Used for lightweight memory tasks like session summarization and reflection.
/// Falls back to the provider fast model when `memory.background_model` is not configured.
pub fn get_memory_background_model_from_config(config: &Config) -> Result<String, LLMError> {
    config.get_memory_background_model().ok_or_else(|| {
        LLMError::Auth(format!(
            "No background memory model configured for provider '{}'",
            config.effective_default_provider()
        ))
    })
}

/// Get the vision-capable model for the current provider from config.
///
/// Used for image understanding tasks.
/// Falls back to the default model when no vision_model is configured.
pub fn get_vision_model_from_config(config: &Config) -> Result<String, LLMError> {
    config.get_vision_model().ok_or_else(|| {
        LLMError::Auth(format!(
            "No model configured for provider '{}'",
            config.effective_default_provider()
        ))
    })
}

fn resolve_role_ref_chain<'a>(
    config: &Config,
    provider_registry: &Arc<ProviderRegistry>,
    candidates: impl IntoIterator<Item = Option<&'a bamboo_domain::ProviderModelRef>>,
) -> Option<ResolvedModel> {
    match try_resolve_role_ref_chain(config, provider_registry, candidates) {
        Ok(model) => model,
        Err(error) => {
            tracing::warn!(%error, "Configured auxiliary model route is unavailable");
            None
        }
    }
}

fn try_resolve_role_ref_chain<'a>(
    config: &Config,
    provider_registry: &Arc<ProviderRegistry>,
    candidates: impl IntoIterator<Item = Option<&'a bamboo_domain::ProviderModelRef>>,
) -> Result<Option<ResolvedModel>, LLMError> {
    Ok(
        try_resolve_role_ref_chain_with_origin(config, provider_registry, candidates)?
            .map(|(model, _)| model),
    )
}

fn try_resolve_role_ref_chain_with_origin<'a>(
    config: &Config,
    provider_registry: &Arc<ProviderRegistry>,
    candidates: impl IntoIterator<Item = Option<&'a bamboo_domain::ProviderModelRef>>,
) -> Result<Option<(ResolvedModel, bool)>, LLMError> {
    // A present-but-invalid reference fails closed. Automatic fallback applies
    // only when a role is unset, never when an explicit provider id is stale.
    let Some(model_ref) = candidates.into_iter().flatten().next() else {
        return Ok(None);
    };
    if model_ref.provider.trim().is_empty()
        || model_ref.model.trim().is_empty()
        || model_ref.provider.trim() != model_ref.provider
        || model_ref.model.trim() != model_ref.model
    {
        return Err(LLMError::Api(
            "Configured provider/model reference is invalid".into(),
        ));
    }
    if let Some(instance) = config.provider_instances.get(&model_ref.provider) {
        if !instance.enabled {
            return Err(LLMError::Auth(format!(
                "Provider instance '{}' is disabled",
                model_ref.provider
            )));
        }
        if bamboo_config::explicit_runtime_models(instance)
            .map_err(LLMError::Api)?
            .is_some_and(|models| !models.contains(&model_ref.model))
        {
            return Err(LLMError::Api(format!(
                "Model '{}' is not admitted to runtime for provider '{}'",
                model_ref.model, model_ref.provider
            )));
        }
    }
    let (provider, managed) =
        provider_registry.provider_for_configured_model_with_origin(config, model_ref)?;
    Ok(Some((
        ResolvedModel::from_ref(provider, model_ref),
        managed,
    )))
}

pub fn try_resolve_exact_model(
    config: &Config,
    registry: &Arc<ProviderRegistry>,
    target: &bamboo_domain::ProviderModelRef,
) -> Result<ResolvedModel, LLMError> {
    try_resolve_role_ref_chain(config, registry, [Some(target)])?
        .ok_or_else(|| LLMError::Api("Configured model target is required".into()))
}

/// A primary route retains the canonical account, its unwrapped provider and
/// the managed proof captured for that same provider generation.
pub struct ResolvedPrimaryModel {
    pub target: bamboo_domain::ProviderModelRef,
    pub provider: Arc<dyn bamboo_llm::LLMProvider>,
    pub managed_origin: Option<Arc<bamboo_llm::provider_registry::ManagedProviderOrigin>>,
}

pub fn try_resolve_primary_model(
    config: &Config,
    registry: &Arc<ProviderRegistry>,
    requested: &bamboo_domain::ProviderModelRef,
) -> Result<ResolvedPrimaryModel, LLMError> {
    if requested.provider.trim().is_empty()
        || requested.model.trim().is_empty()
        || requested.provider.trim() != requested.provider
        || requested.model.trim() != requested.model
    {
        return Err(LLMError::Api(
            "Configured provider/model reference is invalid".into(),
        ));
    }
    let mut target = requested.clone();
    target.provider = resolve_provider_routing_key(config, &target.provider, registry)?;
    // Primary reasoning is carried by the run request; using a role wrapper
    // here would hide the selected registry Arc from managed Gold admission.
    let mut raw_target = target.clone();
    raw_target.reasoning_effort = None;
    let (admitted, was_managed) =
        try_resolve_role_ref_chain_with_origin(config, registry, [Some(&raw_target)])?
            .ok_or_else(|| LLMError::Api("Configured model target is required".into()))?;
    let (provider, managed_origin) =
        registry.provider_for_configured_model_with_managed_origin(config, &raw_target)?;
    if !Arc::ptr_eq(&admitted.provider, &provider) || (was_managed && managed_origin.is_none()) {
        return Err(LLMError::Api(
            "Provider route changed during model admission; retry".into(),
        ));
    }
    Ok(ResolvedPrimaryModel {
        target,
        provider,
        managed_origin,
    })
}

fn try_resolve_legacy_role(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
    model: Option<String>,
) -> Result<Option<ResolvedModel>, LLMError> {
    Ok(
        try_resolve_legacy_role_with_origin(config, provider_name, provider_registry, model)?
            .map(|(model, _)| model),
    )
}

fn try_resolve_legacy_role_with_origin(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
    model: Option<String>,
) -> Result<Option<(ResolvedModel, bool)>, LLMError> {
    if config
        .provider_instances
        .get(provider_name)
        .is_some_and(|instance| !instance.enabled)
    {
        return Err(LLMError::Auth(format!(
            "Provider instance '{provider_name}' is disabled"
        )));
    }
    let model_ref = model.map(|model| bamboo_domain::ProviderModelRef::new(provider_name, model));
    try_resolve_role_ref_chain_with_origin(config, provider_registry, [model_ref.as_ref()])
}

/// Resolve the task summarization model for conversation/task compression.
///
/// Fallback chain: `defaults.task_summary` → `defaults.fast` → `defaults.chat`.
pub fn resolve_task_summary_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    match try_resolve_task_summary_model(config, provider_name, provider_registry) {
        Ok(model) => model,
        Err(error) => {
            tracing::warn!(%error, "Configured task-summary route is unavailable");
            None
        }
    }
}

/// Resolve saved global roles even when an older settings client omitted the
/// primary-chat rollout flag. Only unset roles fall back; an explicit route
/// failure remains an error, never a reason to switch provider accounts.
pub fn try_resolve_task_summary_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Result<Option<ResolvedModel>, LLMError> {
    if let Some(defaults) = config.defaults.as_ref() {
        let model_ref = defaults
            .task_summary
            .as_ref()
            .or(defaults.fast.as_ref())
            .unwrap_or(&defaults.chat);
        return try_resolve_role_ref_chain(config, provider_registry, [Some(model_ref)]);
    }
    try_resolve_fast_model(config, provider_name, provider_registry)
}

/// Resolve the background/fast summarization model considering both
/// `DefaultsConfig` (ProviderModelRef) and legacy provider config paths.
///
/// Resolution order:
/// 1. `defaults.memory_background` (ProviderModelRef, routed via registry)
/// 2. `defaults.fast` (ProviderModelRef, routed via registry)
/// 3. `defaults.chat` (ProviderModelRef, routed via registry)
/// 4. Legacy: `memory.background_model` / provider fast/chat string + registry lookup
pub fn resolve_background_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    match try_resolve_background_model(config, provider_name, provider_registry) {
        Ok(model) => model,
        Err(error) => {
            tracing::warn!(%error, "Configured background route is unavailable");
            None
        }
    }
}

pub fn try_resolve_background_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Result<Option<ResolvedModel>, LLMError> {
    if let Some(defaults) = config.defaults.as_ref() {
        return try_resolve_role_ref_chain(
            config,
            provider_registry,
            [
                defaults.memory_background.as_ref(),
                defaults.fast.as_ref(),
                Some(&defaults.chat),
            ],
        );
    }
    let legacy_memory = config
        .memory()
        .as_ref()
        .and_then(|memory| memory.background_model.as_deref())
        .map(str::trim)
        .filter(|model| !model.is_empty());
    let result = try_resolve_legacy_role(
        config,
        provider_name,
        provider_registry,
        get_memory_background_model_for_provider(config, provider_name),
    );
    let Err(error) = result else {
        return result;
    };
    // Only an explicitly configured legacy memory override may use the
    // managed background-only compatibility route; fast/chat stays ordinary.
    let Some(model) = legacy_memory else {
        return Err(error);
    };
    let target = bamboo_domain::ProviderModelRef::new(provider_name, model);
    match provider_registry.try_legacy_memory_provider(config, &target)? {
        Some(provider) => Ok(Some(ResolvedModel::from_ref(provider, &target))),
        None => Err(error),
    }
}

// A failed Fast selection must not look like an absent role at runner call
// sites: the runner otherwise falls back to the main account. Keep this
// provider local to that execution path, not the public global role resolver.
struct RejectedFastProvider {
    error: FastRouteError,
}

enum FastRouteError {
    Auth(String),
    Api(String),
    Other(String),
}

impl FastRouteError {
    fn from_llm_error(error: LLMError) -> Self {
        match error {
            LLMError::Auth(message) => Self::Auth(message),
            LLMError::Api(message) => Self::Api(message),
            other => Self::Other(other.to_string()),
        }
    }

    fn to_llm_error(&self) -> LLMError {
        match self {
            Self::Auth(message) => LLMError::Auth(message.clone()),
            Self::Api(message) => LLMError::Api(message.clone()),
            Self::Other(message) => LLMError::RequestFailed(message.clone()),
        }
    }
}

#[async_trait::async_trait]
impl bamboo_llm::LLMProvider for RejectedFastProvider {
    fn known_pre_dispatch_error(&self) -> Option<LLMError> {
        Some(self.error.to_llm_error())
    }

    async fn chat_stream(
        &self,
        _messages: &[bamboo_agent_core::Message],
        _tools: &[bamboo_agent_core::ToolSchema],
        _max_output_tokens: Option<u32>,
        _model: &str,
    ) -> Result<bamboo_llm::LLMStream, LLMError> {
        Err(self.error.to_llm_error())
    }

    async fn vision_support_override(&self, _model: &str) -> Option<bool> {
        Some(false)
    }

    async fn list_models(&self) -> Result<Vec<String>, LLMError> {
        Err(self.error.to_llm_error())
    }
}

/// Resolve the Fast name and provider for a runner's auxiliary evaluations.
///
/// `None` config represents a busy live configuration lock, not an unset
/// role, and therefore fails closed. An absent role retains the existing
/// `(None, None)` fallback contract. A rejected role gets a provider that
/// returns its admission error without accessing any network or other account.
/// Callers must pass an authoritative configuration guard, not a cached clone.
#[doc(hidden)]
pub fn resolve_fast_model_for_runner(
    config: Option<&Config>,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> (Option<String>, Option<Arc<dyn bamboo_llm::LLMProvider>>) {
    let Some(config) = config else {
        let error = LLMError::Api(
            "Live configuration is unavailable while selecting a Fast evaluation route".into(),
        );
        return (
            None,
            Some(Arc::new(RejectedFastProvider {
                error: FastRouteError::from_llm_error(error),
            })),
        );
    };

    match try_resolve_fast_model_with_origin(config, provider_name, provider_registry) {
        Ok(Some((model, managed))) => {
            let provider = if managed {
                bamboo_llm::provider::mark_host_queued_route(model.provider)
            } else {
                model.provider
            };
            (Some(model.model_name), Some(provider))
        }
        Ok(None) => (None, None),
        Err(error) => {
            let model_name = config
                .defaults
                .as_ref()
                .map(|defaults| {
                    defaults
                        .fast
                        .as_ref()
                        .unwrap_or(&defaults.chat)
                        .model
                        .clone()
                })
                .or_else(|| get_fast_model_for_provider(config, provider_name));
            (
                model_name,
                Some(Arc::new(RejectedFastProvider {
                    error: FastRouteError::from_llm_error(error),
                })),
            )
        }
    }
}

/// Resolve the fast model for lightweight tasks like title generation.
pub fn resolve_fast_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    match try_resolve_fast_model(config, provider_name, provider_registry) {
        Ok(model) => model,
        Err(error) => {
            tracing::warn!(%error, "Configured fast route is unavailable");
            None
        }
    }
}

pub fn try_resolve_fast_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Result<Option<ResolvedModel>, LLMError> {
    Ok(
        try_resolve_fast_model_with_origin(config, provider_name, provider_registry)?
            .map(|(model, _)| model),
    )
}

fn try_resolve_fast_model_with_origin(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Result<Option<(ResolvedModel, bool)>, LLMError> {
    if let Some(defaults) = config.defaults.as_ref() {
        return try_resolve_role_ref_chain_with_origin(
            config,
            provider_registry,
            [defaults.fast.as_ref(), Some(&defaults.chat)],
        );
    }
    try_resolve_legacy_role_with_origin(
        config,
        provider_name,
        provider_registry,
        get_fast_model_for_provider(config, provider_name),
    )
}

/// Resolve the vision-capable model for image understanding.
pub fn resolve_vision_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    if let Some(defaults) = config.defaults.as_ref() {
        return resolve_role_ref_chain(
            config,
            provider_registry,
            [
                defaults.vision.as_ref(),
                defaults.fast.as_ref(),
                Some(&defaults.chat),
            ],
        );
    }
    let model_name = if let Some(instance) = config.provider_instances.get(provider_name) {
        if !instance.enabled {
            return None;
        }
        instance
            .vision_model
            .as_deref()
            .map(str::trim)
            .filter(|model| !model.is_empty())
            .map(ToString::to_string)
            .or_else(|| get_fast_model_for_provider(config, provider_name))?
    } else {
        config.get_vision_model()?
    };
    let provider = provider_registry.get(provider_name)?;
    Some(ResolvedModel::new(provider, model_name))
}

/// Resolve the planning/coordination model for architecture and task decomposition.
///
/// Fallback chain: `defaults.planning` → `defaults.fast` → `defaults.chat`.
pub fn resolve_planning_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    if let Some(defaults) = config.defaults.as_ref() {
        return resolve_role_ref_chain(
            config,
            provider_registry,
            [
                defaults.planning.as_ref(),
                defaults.fast.as_ref(),
                Some(&defaults.chat),
            ],
        );
    }
    resolve_fast_model(config, provider_name, provider_registry)
}

/// Resolve the search/navigation model for grep, file listing, and symbol resolution.
///
/// Fallback chain: `defaults.search` → `defaults.fast` → legacy fast model → default chat model.
pub fn resolve_search_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    if let Some(defaults) = config.defaults.as_ref() {
        return resolve_role_ref_chain(
            config,
            provider_registry,
            [
                defaults.search.as_ref(),
                defaults.fast.as_ref(),
                Some(&defaults.chat),
            ],
        );
    }
    resolve_fast_model(config, provider_name, provider_registry)
}

/// Resolve the code review model for PR and code analysis tasks.
///
/// Fallback chain: `defaults.code_review` → `defaults.fast` → `defaults.chat`.
pub fn resolve_code_review_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
) -> Option<ResolvedModel> {
    if let Some(defaults) = config.defaults.as_ref() {
        return resolve_role_ref_chain(
            config,
            provider_registry,
            [
                defaults.code_review.as_ref(),
                defaults.fast.as_ref(),
                Some(&defaults.chat),
            ],
        );
    }
    resolve_fast_model(config, provider_name, provider_registry)
}

/// Resolve the provider+model reference for a specific subagent type.
///
/// Fallback chain: `defaults.subagent_models[type]` → `defaults.sub_agent` →
/// `defaults.fast`/legacy fast → `defaults.chat`/legacy default.
pub fn resolve_subagent_model_ref(
    config: &Config,
    provider_name: &str,
    _provider_registry: &Arc<ProviderRegistry>,
    subagent_type: &str,
) -> Option<bamboo_domain::ProviderModelRef> {
    if let Some(defaults) = config.defaults.as_ref() {
        let candidate_refs = [
            defaults.subagent_models.get(subagent_type),
            defaults.sub_agent.as_ref(),
            defaults.fast.as_ref(),
            Some(&defaults.chat),
        ];

        let model_ref = candidate_refs.into_iter().flatten().next()?;
        // This is selection, not admission. Preserve an explicit invalid ref
        // so the real child admission rejects it rather than inheriting the
        // parent's unrelated model after `None`.
        return Some(model_ref.clone());
    }

    let legacy_model = if let Some(instance) = config.provider_instances.get(provider_name) {
        // Retain a disabled instance's configured intent for final admission.
        instance
            .fast_model
            .as_deref()
            .map(str::trim)
            .filter(|model| !model.is_empty())
            .or_else(|| {
                instance
                    .model
                    .as_deref()
                    .map(str::trim)
                    .filter(|model| !model.is_empty())
            })
            .map(ToString::to_string)
            .or_else(|| (instance.provider_type == "copilot").then(|| "gpt-4o".to_string()))
    } else {
        // Legacy provider entries historically treated a blank fast selection
        // as unset and inherited the parent rather than selecting an empty ID.
        get_fast_model_for_provider(config, provider_name).filter(|model| !model.trim().is_empty())
    };
    legacy_model.map(|model| bamboo_domain::ProviderModelRef::new(provider_name, model))
}

/// Resolve the model for a specific subagent type.
///
/// Fallback chain: `defaults.subagent_models[type]` → `defaults.sub_agent` →
/// `defaults.fast`/legacy fast → `defaults.chat`/legacy default.
pub fn resolve_subagent_model(
    config: &Config,
    provider_name: &str,
    provider_registry: &Arc<ProviderRegistry>,
    subagent_type: &str,
) -> Option<ResolvedModel> {
    let model_ref =
        resolve_subagent_model_ref(config, provider_name, provider_registry, subagent_type)?;
    try_resolve_exact_model(config, provider_registry, &model_ref).ok()
}

/// Resolve the image-fallback configuration from a config snapshot.
///
/// Returns `Ok(None)` when image fallback is disabled, `Ok(Some(..))` with the
/// resolved mode (and vision model, for `Vision` mode), or `Err` on an invalid
/// `hooks.image_fallback.mode` value.
pub fn resolve_image_fallback(
    config_snapshot: &Config,
) -> Result<Option<crate::ImageFallbackConfig>, String> {
    use crate::ImageFallbackMode;

    if !config_snapshot.hooks.image_fallback.enabled {
        return Ok(None);
    }

    let mode_str = config_snapshot
        .hooks
        .image_fallback
        .mode
        .trim()
        .to_ascii_lowercase();

    let mode = match mode_str.as_str() {
        "placeholder" => ImageFallbackMode::Placeholder,
        "error" => ImageFallbackMode::Error,
        "ocr" => ImageFallbackMode::Ocr,
        "vision" => ImageFallbackMode::Vision,
        other => {
            return Err(format!(
                "Invalid config: hooks.image_fallback.mode must be 'placeholder', 'error', 'ocr', or 'vision' (got '{other}')"
            ));
        }
    };

    let vision_model = if mode == ImageFallbackMode::Vision {
        config_snapshot
            .defaults
            .as_ref()
            .map(|defaults| {
                defaults
                    .vision
                    .as_ref()
                    .or(defaults.fast.as_ref())
                    .unwrap_or(&defaults.chat)
                    .model
                    .clone()
            })
            .or_else(|| config_snapshot.get_vision_model())
    } else {
        None
    };

    Ok(Some(crate::ImageFallbackConfig { mode, vision_model }))
}

/// Mark a Host-derived fallback for selection from the execution-time config.
/// The public low-level resolver retains its snapshot-model behavior; only a
/// caller that knows this value came from config should use this conversion.
#[doc(hidden)]
pub fn live_config_image_fallback(
    mut fallback: Option<crate::ImageFallbackConfig>,
) -> Option<crate::ImageFallbackConfig> {
    if let Some(fallback) = fallback.as_mut() {
        if fallback.mode == crate::ImageFallbackMode::Vision {
            fallback.vision_model = None;
        }
    }
    fallback
}

/// Resolve a Host-derived mode, leaving the Vision pair to the runtime's one
/// execution-time config snapshot rather than retaining a model-only value.
#[doc(hidden)]
pub fn resolve_live_image_fallback(
    config: &Config,
) -> Result<Option<crate::ImageFallbackConfig>, String> {
    resolve_image_fallback(config).map(live_config_image_fallback)
}

#[cfg(test)]
mod tests {
    use super::*;
    use bamboo_agent_core::tools::ToolSchema;
    use bamboo_agent_core::Message;
    use bamboo_config::CopilotConfig;
    use bamboo_config::DefaultsConfig;
    use bamboo_config::{OpenAIConfig, ProviderConfigs};
    use bamboo_domain::ProviderModelRef;
    use bamboo_llm::{LLMProvider, LLMStream};
    use std::collections::HashMap;

    macro_rules! test_config {
        (@assign $config:ident, providers, $value:expr) => {
            *$config.providers_mut() = $value;
        };
        (@assign $config:ident, memory, $value:expr) => {
            *$config.memory_mut() = $value;
        };
        (@assign $config:ident, subagents, $value:expr) => {
            *$config.subagents_mut() = $value;
        };
        (@assign $config:ident, $field:ident, $value:expr) => {
            $config.$field = $value;
        };
        ($($field:ident: $value:expr),* $(,)?) => {{
            let mut config = Config::default();
            $(test_config!(@assign config, $field, $value);)*
            config
        }};
    }

    struct NoopProvider;

    #[async_trait::async_trait]
    impl LLMProvider for NoopProvider {
        async fn chat_stream(
            &self,
            _messages: &[Message],
            _tools: &[ToolSchema],
            _max_output_tokens: Option<u32>,
            _model: &str,
        ) -> Result<LLMStream, LLMError> {
            Err(LLMError::Api("noop".to_string()))
        }
    }

    fn test_registry() -> Arc<ProviderRegistry> {
        let mut providers: HashMap<String, Arc<dyn LLMProvider>> = HashMap::new();
        providers.insert("openai".to_string(), Arc::new(NoopProvider));
        Arc::new(ProviderRegistry::new(providers, "openai".to_string()))
    }

    fn registry_with_provider_ids(ids: &[&str], default: &str) -> Arc<ProviderRegistry> {
        let providers = ids
            .iter()
            .map(|id| {
                (
                    (*id).to_string(),
                    Arc::new(NoopProvider) as Arc<dyn LLMProvider>,
                )
            })
            .collect();
        Arc::new(ProviderRegistry::new(providers, default.to_string()))
    }

    #[tokio::test]
    async fn legacy_background_resolution_keeps_session_provider_and_fast_fallback() {
        let mut config = Config::default();
        config.default_provider_instance = Some("account-a".into());
        config.defaults = None;
        for (id, model, key) in [
            ("account-a", "chat-a", "synthetic-key-a"),
            ("account-b", "chat-b", "synthetic-key-b"),
        ] {
            config.provider_instances.insert(
                id.into(),
                serde_json::from_value(serde_json::json!({
                    "provider_type":"openai", "enabled":true, "api_key":key,
                    "base_url":"http://127.0.0.1:1", "model":model
                }))
                .unwrap(),
            );
        }
        config
            .memory_mut()
            .get_or_insert_with(Default::default)
            .background_model = Some("memory-v1".into());
        let dir = tempfile::tempdir().unwrap();
        let registry = Arc::new(
            ProviderRegistry::from_config(&config, dir.path().into())
                .await
                .unwrap(),
        );
        let b = registry.get("account-b").unwrap();
        for flag in [false, true] {
            config.features.provider_model_ref = flag;
            let resolved = try_resolve_background_model(&config, "account-b", &registry)
                .unwrap()
                .unwrap();
            assert_eq!(resolved.model_name, "memory-v1");
            assert!(Arc::ptr_eq(&resolved.provider, &b));
        }
        config.memory_mut().as_mut().unwrap().background_model = Some("memory-v2".into());
        let live = try_resolve_background_model(&config, "account-b", &registry)
            .unwrap()
            .unwrap();
        assert_eq!(live.model_name, "memory-v2");
        assert!(Arc::ptr_eq(&live.provider, &b));
        config
            .provider_instances
            .get_mut("account-b")
            .unwrap()
            .extra
            .insert("runtime_models".into(), serde_json::json!(["chat-b"]));
        assert!(try_resolve_background_model(&config, "account-b", &registry).is_err());
        config
            .provider_instances
            .get_mut("account-b")
            .unwrap()
            .extra
            .remove("runtime_models");
        config.memory_mut().as_mut().unwrap().background_model = None;
        let fast = try_resolve_background_model(&config, "account-b", &registry)
            .unwrap()
            .unwrap();
        assert_eq!(fast.model_name, "chat-b");
        assert!(Arc::ptr_eq(&fast.provider, &b));
    }

    #[test]
    fn routing_contract_saved_auxiliary_roles_keep_complete_targets_for_every_chat_flag() {
        use crate::app_context::model_routing_test_support::RoutingContext;
        for flag in [None, Some(false), Some(true)] {
            let state = RoutingContext::new(flag);
            let mut config = state.config.try_read().unwrap().clone();
            let defaults = config.defaults.as_mut().unwrap();
            let memory = ProviderModelRef::new("memory-c", "background-c");
            let fast = ProviderModelRef::new("fast-b", "cheap-b");
            defaults.task_summary = Some(memory.clone());
            defaults.vision = Some(memory.clone());
            defaults.planning = Some(memory.clone());
            defaults.search = Some(fast.clone());
            defaults.code_review = Some(memory.clone());
            defaults.sub_agent = Some(fast.clone());
            defaults.subagent_models.insert("planner".into(), memory);
            // Reserved planning/search/code-review selectors are tested as
            // selectors only: they do not constitute a wired model consumer.
            for (resolved, provider, model) in [
                (
                    resolve_fast_model(&config, "chat-a", &state.registry),
                    "fast-b",
                    "cheap-b",
                ),
                (
                    resolve_task_summary_model(&config, "chat-a", &state.registry),
                    "memory-c",
                    "background-c",
                ),
                (
                    resolve_background_model(&config, "chat-a", &state.registry),
                    "memory-c",
                    "background-c",
                ),
                (
                    resolve_vision_model(&config, "chat-a", &state.registry),
                    "memory-c",
                    "background-c",
                ),
                (
                    resolve_planning_model(&config, "chat-a", &state.registry),
                    "memory-c",
                    "background-c",
                ),
                (
                    resolve_search_model(&config, "chat-a", &state.registry),
                    "fast-b",
                    "cheap-b",
                ),
                (
                    resolve_code_review_model(&config, "chat-a", &state.registry),
                    "memory-c",
                    "background-c",
                ),
                (
                    resolve_subagent_model(&config, "chat-a", &state.registry, "coder"),
                    "fast-b",
                    "cheap-b",
                ),
                (
                    resolve_subagent_model(&config, "chat-a", &state.registry, "planner"),
                    "memory-c",
                    "background-c",
                ),
            ] {
                let resolved = resolved.unwrap();
                assert_eq!(resolved.model_name, model, "flag {flag:?}");
                assert!(Arc::ptr_eq(
                    &resolved.provider,
                    &state.registry.get(provider).unwrap()
                ));
            }
            state.assert_no_requests();
        }
    }

    #[test]
    fn primary_route_canonicalizes_alias_and_keeps_raw_provider_and_effort() {
        let mut config = Config::default();
        config.provider_instances.insert(
            "work-openai".into(),
            serde_json::from_value(serde_json::json!({
                "provider_type":"openai", "enabled":true, "model":"chat-model",
                "runtime_models":["chat-model"]
            }))
            .unwrap(),
        );
        config.default_provider_instance = Some("work-openai".into());
        let registry = registry_with_provider_ids(&["work-openai"], "work-openai");
        let target = bamboo_domain::ProviderModelRef::new("openai", "chat-model")
            .with_reasoning_effort(ReasoningEffort::High);
        let selected = try_resolve_primary_model(&config, &registry, &target).unwrap();
        assert_eq!(selected.target.provider, "work-openai");
        assert_eq!(
            selected.target.reasoning_effort,
            Some(ReasoningEffort::High)
        );
        assert!(Arc::ptr_eq(
            &selected.provider,
            &registry.get("work-openai").unwrap()
        ));
        assert!(selected.managed_origin.is_none());

        config.provider_instances.insert(
            "openai".into(),
            serde_json::from_value(serde_json::json!({
                "provider_type":"openai", "enabled":false, "model":"chat-model"
            }))
            .unwrap(),
        );
        let error = try_resolve_primary_model(&config, &registry, &target)
            .err()
            .expect("a disabled exact ID must not route to an alias");
        assert!(error.to_string().contains("disabled"));
    }

    #[test]
    fn subagent_resolved_model_requires_exact_current_admission() {
        use crate::app_context::model_routing_test_support::RoutingContext;

        let state = RoutingContext::new(None);
        let mut config = state.config.try_read().unwrap().clone();
        config.defaults.as_mut().unwrap().sub_agent =
            Some(ProviderModelRef::new("fast-b", "cheap-b"));
        let resolved = resolve_subagent_model(&config, "chat-a", &state.registry, "coder")
            .expect("the selected admitted role must resolve");
        assert_eq!(resolved.model_name, "cheap-b");
        assert!(Arc::ptr_eq(
            &resolved.provider,
            &state.registry.get("fast-b").unwrap()
        ));

        let instance = config.provider_instances.get_mut("fast-b").unwrap();
        instance.enabled = false;
        assert!(resolve_subagent_model(&config, "chat-a", &state.registry, "coder").is_none());

        let instance = config.provider_instances.get_mut("fast-b").unwrap();
        instance.enabled = true;
        instance
            .extra
            .insert("runtime_models".into(), serde_json::json!([]));
        assert!(resolve_subagent_model(&config, "chat-a", &state.registry, "coder").is_none());
        state.assert_no_requests();
    }

    #[test]
    fn provider_type_alias_resolves_to_matching_default_instance() {
        let mut config = Config::default();
        config.provider_instances.insert(
            "work-openai".to_string(),
            serde_json::from_value(serde_json::json!({
                "provider_type": "openai",
                "enabled": true
            }))
            .unwrap(),
        );
        config.provider_instances.insert(
            "main-anthropic".to_string(),
            serde_json::from_value(serde_json::json!({
                "provider_type": "anthropic",
                "enabled": true
            }))
            .unwrap(),
        );
        config.default_provider_instance = Some("main-anthropic".to_string());
        let registry =
            registry_with_provider_ids(&["main-anthropic", "work-openai"], "main-anthropic");

        assert_eq!(
            resolve_provider_routing_key(&config, "openai", &registry).unwrap(),
            "work-openai"
        );
        assert_eq!(
            resolve_provider_routing_key(&config, "anthropic", &registry).unwrap(),
            "main-anthropic"
        );
    }

    #[test]
    fn provider_type_alias_uses_lexical_instance_but_exact_unavailable_id_fails_closed() {
        let mut config = Config::default();
        for id in ["z-openai", "a-openai"] {
            config.provider_instances.insert(
                id.to_string(),
                serde_json::from_value(serde_json::json!({
                    "provider_type": "openai",
                    "enabled": true
                }))
                .unwrap(),
            );
        }
        config.provider_instances.insert(
            "openai".to_string(),
            serde_json::from_value(serde_json::json!({
                "provider_type": "openai",
                "enabled": false
            }))
            .unwrap(),
        );
        let registry = registry_with_provider_ids(&["a-openai", "z-openai"], "a-openai");

        let error = resolve_provider_routing_key(&config, "openai", &registry)
            .unwrap_err()
            .to_string();
        assert!(error.contains("disabled"));

        config.provider_instances.remove("openai");
        assert_eq!(
            resolve_provider_routing_key(&config, "openai", &registry).unwrap(),
            "a-openai"
        );
        assert!(resolve_provider_routing_key(&config, "typo", &registry).is_err());
    }

    #[test]
    fn test_get_model_from_openai_config() {
        let config = test_config! {
            provider: "openai".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: Some("gpt-4o".to_string()),
                    fast_model: None,
                    vision_model: None,
                    reasoning_effort: None,
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        let result = get_default_model_from_config(&config);
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), "gpt-4o");
    }

    #[test]
    fn instance_models_are_authoritative_over_stale_legacy_slot() {
        let mut config = test_config! {
            provider: "openai".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "legacy".to_string(),
                    model: Some("gpt-stale".to_string()),
                    fast_model: Some("gpt-stale-fast".to_string()),
                    vision_model: Some("gpt-stale-vision".to_string()),
                    ..OpenAIConfig::default()
                }),
                ..ProviderConfigs::default()
            },
        };
        config.provider_instances.insert(
            "work".to_string(),
            serde_json::from_value(serde_json::json!({
                "provider_type": "openai",
                "model": "gpt-instance",
                "fast_model": "gpt-instance-fast",
                "vision_model": "gpt-instance-vision",
                "enabled": true
            }))
            .unwrap(),
        );
        config.default_provider_instance = Some("work".to_string());

        assert_eq!(
            get_default_model_from_config(&config).unwrap(),
            "gpt-instance"
        );
        assert_eq!(
            get_fast_model_for_provider(&config, "work").as_deref(),
            Some("gpt-instance-fast")
        );
        assert_eq!(
            get_schedule_model_from_config(&config).unwrap(),
            "gpt-instance-fast"
        );
        assert_eq!(
            get_vision_model_from_config(&config).unwrap(),
            "gpt-instance-vision"
        );
    }

    #[test]
    fn disabled_instance_model_does_not_fall_back_to_legacy_provider() {
        let mut config = test_config! {
            provider: "openai".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    model: Some("gpt-stale".to_string()),
                    ..OpenAIConfig::default()
                }),
                ..ProviderConfigs::default()
            },
        };
        config.provider_instances.insert(
            "work".to_string(),
            serde_json::from_value(serde_json::json!({
                "provider_type": "openai",
                "model": "gpt-instance",
                "enabled": false
            }))
            .unwrap(),
        );
        config.default_provider_instance = Some("work".to_string());

        let error = get_default_model_from_config(&config)
            .unwrap_err()
            .to_string();
        assert!(error.contains("disabled"));
        assert!(get_fast_model_for_provider(&config, "work").is_none());
    }

    #[test]
    fn test_error_when_model_not_configured() {
        let config = test_config! {
            provider: "openai".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: None, // No model configured
                    fast_model: None,
                    vision_model: None,
                    reasoning_effort: None,
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        let result = get_default_model_from_config(&config);
        assert!(result.is_err());
        assert!(result
            .unwrap_err()
            .to_string()
            .contains("model must be specified"));
    }

    #[test]
    fn test_get_model_from_copilot_provider_config() {
        let config = test_config! {
            provider: "copilot".to_string(),
            providers: ProviderConfigs {
                copilot: Some(CopilotConfig {
                    enabled: true,
                    headless_auth: false,
                    model: Some("gpt-4o-mini".to_string()),
                    fast_model: None,
                    vision_model: None,
                    reasoning_effort: None,
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        let result = get_default_model_from_config(&config);
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), "gpt-4o-mini");
    }

    #[test]
    fn test_get_model_from_copilot_default_fallback() {
        let config = test_config! {
            provider: "copilot".to_string(),
            providers: ProviderConfigs::default(),
        };

        let result = get_default_model_from_config(&config);
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), "gpt-4o");
    }

    #[test]
    fn test_get_default_model_for_specific_provider() {
        let config = test_config! {
            provider: "anthropic".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: Some("gpt-4o".to_string()),
                    fast_model: Some("gpt-4o-mini".to_string()),
                    vision_model: None,
                    reasoning_effort: Some(ReasoningEffort::Medium),
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        let result = get_default_model_for_provider(&config, "openai").expect("openai config");
        assert_eq!(result, "gpt-4o");
    }

    #[test]
    fn test_get_fast_model_for_specific_provider() {
        let config = test_config! {
            provider: "anthropic".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: Some("gpt-4o".to_string()),
                    fast_model: Some("gpt-4o-mini".to_string()),
                    vision_model: None,
                    reasoning_effort: Some(ReasoningEffort::Medium),
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        assert_eq!(
            get_fast_model_for_provider(&config, "openai").as_deref(),
            Some("gpt-4o-mini")
        );
    }

    #[test]
    fn test_get_schedule_model_from_config_prefers_fast_model() {
        let config = test_config! {
            provider: "openai".to_string(),
            defaults: None,
            features: bamboo_config::FeatureFlags {
                provider_model_ref: false,
                ..Default::default()
            },
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: Some("gpt-4o".to_string()),
                    fast_model: Some("gpt-4o-mini".to_string()),
                    vision_model: None,
                    reasoning_effort: None,
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        let result = get_schedule_model_from_config(&config);
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), "gpt-4o-mini");
    }

    #[test]
    fn test_get_schedule_model_from_config_falls_back_to_default_model() {
        let config = test_config! {
            provider: "openai".to_string(),
            defaults: None,
            features: bamboo_config::FeatureFlags {
                provider_model_ref: false,
                ..Default::default()
            },
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: Some("gpt-4o".to_string()),
                    fast_model: None,
                    vision_model: None,
                    reasoning_effort: None,
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        let result = get_schedule_model_from_config(&config);
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), "gpt-4o");
    }

    #[test]
    fn test_get_schedule_model_from_config_prefers_defaults_fast_over_chat() {
        let config = test_config! {
            provider: "openai".to_string(),
            features: bamboo_config::FeatureFlags {
                provider_model_ref: true,
                ..Default::default()
            },
            defaults: Some(DefaultsConfig {
                chat: ProviderModelRef::new("openai", "gpt-chat"),
                fast: Some(ProviderModelRef::new("openai", "gpt-fast")),
                task_summary: None,
                vision: None,
                memory_background: None,
                planning: None,
                search: None,
                code_review: None,
                sub_agent: None,
                subagent_models: HashMap::new(),
            }),
        };

        let result = get_schedule_model_from_config(&config);
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), "gpt-fast");
    }

    #[test]
    fn test_get_reasoning_effort_for_specific_provider() {
        let config = test_config! {
            provider: "anthropic".to_string(),
            providers: ProviderConfigs {
                openai: Some(OpenAIConfig {
                    api_key: "test".to_string(),
                    api_key_from_env: false,
                    api_key_encrypted: None,
                    credential_ref: None,
                    base_url: None,
                    model: Some("gpt-4o".to_string()),
                    fast_model: Some("gpt-4o-mini".to_string()),
                    vision_model: None,
                    reasoning_effort: Some(ReasoningEffort::Medium),
                    responses_only_models: vec![],
                    request_overrides: None,
                    extra: Default::default(),
                }),
                ..ProviderConfigs::default()
            },
        };

        assert_eq!(
            get_reasoning_effort_for_provider(&config, "openai"),
            Some(ReasoningEffort::Medium)
        );
    }
    #[test]
    fn resolve_subagent_model_ref_prefers_sub_agent_over_fast() {
        let config = test_config! {
            provider: "openai".to_string(),
            features: bamboo_config::FeatureFlags {
                provider_model_ref: true,
                ..Default::default()
            },
            defaults: Some(DefaultsConfig {
                chat: ProviderModelRef::new("openai", "gpt-chat"),
                fast: Some(ProviderModelRef::new("openai", "gpt-fast")),
                task_summary: None,
                vision: None,
                memory_background: None,
                planning: None,
                search: None,
                code_review: None,
                sub_agent: Some(ProviderModelRef::new("openai", "gpt-sub-agent")),
                subagent_models: HashMap::new(),
            }),
        };

        let resolved = resolve_subagent_model_ref(&config, "openai", &test_registry(), "coder")
            .expect("sub-agent model should resolve");

        assert_eq!(resolved, ProviderModelRef::new("openai", "gpt-sub-agent"));
    }

    #[test]
    fn resolve_subagent_model_ref_falls_back_to_fast_when_sub_agent_unset() {
        let config = test_config! {
            provider: "openai".to_string(),
            features: bamboo_config::FeatureFlags {
                provider_model_ref: true,
                ..Default::default()
            },
            defaults: Some(DefaultsConfig {
                chat: ProviderModelRef::new("openai", "gpt-chat"),
                fast: Some(ProviderModelRef::new("openai", "gpt-fast")),
                task_summary: None,
                vision: None,
                memory_background: None,
                planning: None,
                search: None,
                code_review: None,
                sub_agent: None,
                subagent_models: HashMap::new(),
            }),
        };

        let resolved = resolve_subagent_model_ref(&config, "openai", &test_registry(), "coder")
            .expect("fast model should resolve");

        assert_eq!(resolved, ProviderModelRef::new("openai", "gpt-fast"));
    }

    #[test]
    fn every_unset_specialist_role_falls_back_to_fast_before_chat() {
        let config = test_config! {
            provider: "openai".to_string(),
            features: bamboo_config::FeatureFlags {
                provider_model_ref: true,
                ..Default::default()
            },
            defaults: Some(DefaultsConfig {
                chat: ProviderModelRef::new("openai", "gpt-chat"),
                fast: Some(ProviderModelRef::new("openai", "gpt-fast")),
                task_summary: None,
                vision: None,
                memory_background: None,
                planning: None,
                search: None,
                code_review: None,
                sub_agent: None,
                subagent_models: HashMap::new(),
            }),
        };
        let registry = test_registry();

        for resolved in [
            resolve_task_summary_model(&config, "openai", &registry),
            resolve_background_model(&config, "openai", &registry),
            resolve_vision_model(&config, "openai", &registry),
            resolve_planning_model(&config, "openai", &registry),
            resolve_search_model(&config, "openai", &registry),
            resolve_code_review_model(&config, "openai", &registry),
            resolve_subagent_model(&config, "openai", &registry, "coder"),
        ] {
            assert_eq!(
                resolved.map(|model| model.model_name),
                Some("gpt-fast".to_string())
            );
        }
    }

    #[test]
    fn every_unset_specialist_role_falls_back_to_chat_when_fast_is_unset() {
        let config = test_config! {
            provider: "openai".to_string(),
            features: bamboo_config::FeatureFlags {
                provider_model_ref: true,
                ..Default::default()
            },
            defaults: Some(DefaultsConfig {
                chat: ProviderModelRef::new("openai", "gpt-chat"),
                fast: None,
                task_summary: None,
                vision: None,
                memory_background: None,
                planning: None,
                search: None,
                code_review: None,
                sub_agent: None,
                subagent_models: HashMap::new(),
            }),
        };
        let registry = test_registry();

        for resolved in [
            resolve_task_summary_model(&config, "openai", &registry),
            resolve_background_model(&config, "openai", &registry),
            resolve_vision_model(&config, "openai", &registry),
            resolve_planning_model(&config, "openai", &registry),
            resolve_search_model(&config, "openai", &registry),
            resolve_code_review_model(&config, "openai", &registry),
            resolve_subagent_model(&config, "openai", &registry, "coder"),
        ] {
            assert_eq!(
                resolved.map(|model| model.model_name),
                Some("gpt-chat".to_string())
            );
        }
    }

    // ---- S-T1.1: infer_provider mapping ----

    #[test]
    fn infer_provider_maps_known_families() {
        // claude* → anthropic
        assert_eq!(
            infer_provider("claude-3-7-sonnet").as_deref(),
            Some("anthropic")
        );
        assert_eq!(infer_provider("Claude-Opus").as_deref(), Some("anthropic"));
        // gpt* → openai
        assert_eq!(infer_provider("gpt-4o").as_deref(), Some("openai"));
        assert_eq!(infer_provider("GPT-4o-mini").as_deref(), Some("openai"));
        // o-series → openai
        assert_eq!(infer_provider("o1").as_deref(), Some("openai"));
        assert_eq!(infer_provider("o3-mini").as_deref(), Some("openai"));
        assert_eq!(infer_provider("o4-mini").as_deref(), Some("openai"));
        // gemini* → gemini
        assert_eq!(infer_provider("gemini-1.5-pro").as_deref(), Some("gemini"));
        // unknown / empty → None
        assert_eq!(infer_provider("llama-3"), None);
        assert_eq!(infer_provider("opus"), None); // no o-digit, not claude*
        assert_eq!(infer_provider("  "), None);
        assert_eq!(infer_provider(""), None);
    }
}