import {
  PROVIDER_ID_TO_ALIAS,
  PROVIDER_MODELS,
} from "@omniroute/open-sse/config/providerModels.ts";
import { parseModel, resolveCanonicalProviderModel } from "@omniroute/open-sse/services/model.ts";
import {
  findModelSpecIdByExactOrAlias,
  getAuthoritativeContextWindow,
  getAuthoritativeProviderContextWindow,
  getModelSpec,
  type ModelSpec,
} from "@/shared/constants/modelSpecs";
import { getSyncedCapability } from "@/lib/modelsDevSync";
import { MODELS_DEV_PROVIDER_MAP } from "@/lib/modelsDevSync/transform";
import { getModelContextOverride } from "@/lib/db/modelContextOverrides";
import { getModelCapabilityOverride } from "@/lib/db/modelCapabilityOverrides";
import { isVisionModelId } from "@/shared/constants/visionModels";
import { getUnsupportedParams } from "@omniroute/open-sse/config/providerRegistry.ts";
import {
  getLearnedThinkingCap,
  GEMINI_FALLBACK_THINKING_CAP,
} from "@omniroute/open-sse/services/learnedThinkingCaps.ts";

const TOOL_CALLING_UNSUPPORTED_PATTERNS: string[] = [
  // Specialty / non-chat surfaces must never inherit optimistic tool defaults (#8016)
  "whisper",
  "tts-1",
  "gpt-4o-mini-tts",
  "omni-moderation",
  "moderation",
  "eleven_multilingual",
  "eleven_turbo",
  "seedance",
  "/veo",
  "veo-",
  "rerank",
  "embedding",
  "dall-e",
  "flux-",
  "stable-diffusion",
];
const REASONING_UNSUPPORTED_PATTERNS = [
  "antigravity/claude-sonnet-4-6",
  "antigravity/claude-sonnet-4-5",
  "antigravity/claude-sonnet-4",
  // Non-Claude antigravity models don't support thinking params (#1361)
  "antigravity/gemini-",
  "antigravity/gpt-oss-",
  "antigravity/gemini-3",
  "antigravity/tab_",
  // Specialty / non-chat surfaces (#8016)
  "whisper",
  "tts-1",
  "gpt-4o-mini-tts",
  "omni-moderation",
  "moderation",
  "eleven_multilingual",
  "eleven_turbo",
  "seedance",
  "/veo",
  "veo-",
  "rerank",
  "embedding",
  "dall-e",
  "flux-",
  "stable-diffusion",
];

/** Catalog/API surface types that are not chat completions. */
const NON_CHAT_SURFACE_TYPES = new Set([
  "audio",
  "video",
  "image",
  "moderation",
  "rerank",
  "embedding",
  "music",
]);

export function isNonChatCatalogSurface(type: unknown): boolean {
  return typeof type === "string" && NON_CHAT_SURFACE_TYPES.has(type);
}

const MAX_TOKENS_UNSUPPORTED_PATTERNS = [
  "o1-preview",
  "o1-mini",
  "o1",
  "o3-mini",
  "o3",
  "gpt-5.4",
  "gpt-5.5",
];

type CapabilityInput =
  | string
  | {
      provider?: string | null;
      model?: string | null;
    };

type SyncedCapabilities = ReturnType<typeof getSyncedCapability>;

/**
 * Controls whether persisted operator/discovery overrides participate in resolution.
 * Omit it (the public default) to resolve effective runtime capabilities. Catalog
 * reconciliation alone uses `persistedOverrides: false` to compare discovery with
 * static/synced catalog data without feeding an existing override back into itself.
 */
export interface ResolveModelCapabilitiesOptions {
  persistedOverrides?: boolean;
}

export interface ResolvedModelCapabilities {
  provider: string | null;
  model: string | null;
  rawModel: string | null;
  toolCalling: boolean;
  reasoning: boolean;
  supportsThinking: boolean | null;
  supportsTools: boolean | null;
  supportsVision: boolean | null;
  supportsMaxTokens: boolean;
  attachment: boolean | null;
  structuredOutput: boolean | null;
  temperature: boolean | null;
  contextWindow: number | null;
  maxInputTokens: number | null;
  maxOutputTokens: number | null;
  defaultThinkingBudget: number;
  thinkingBudgetCap: number | null;
  thinkingOverhead: number | null;
  adaptiveMaxTokens: number | null;
  family: string | null;
  status: string | null;
  openWeights: boolean | null;
  knowledgeCutoff: string | null;
  releaseDate: string | null;
  lastUpdated: string | null;
  modalitiesInput: string[];
  modalitiesOutput: string[];
  interleavedField: string | null;
}

function toNonEmptyString(value: unknown): string | null {
  return typeof value === "string" && value.trim().length > 0 ? value.trim() : null;
}

function parseModalities(value: string | null | undefined): string[] {
  if (typeof value !== "string" || value.trim().length === 0) return [];
  try {
    const parsed = JSON.parse(value);
    return Array.isArray(parsed)
      ? parsed.filter((entry): entry is string => typeof entry === "string" && entry.length > 0)
      : [];
  } catch {
    return [];
  }
}

function getRegistryModel(providerIdOrAlias: string | null, modelId: string | null) {
  if (!providerIdOrAlias || !modelId) return null;
  const providerAlias = PROVIDER_ID_TO_ALIAS[providerIdOrAlias] || providerIdOrAlias;
  const models = PROVIDER_MODELS[providerAlias];
  if (!Array.isArray(models)) return null;
  return models.find((model) => model?.id === modelId) || null;
}

function resolveCapabilityInput(input: CapabilityInput) {
  if (typeof input === "string") {
    const parsed = parseModel(input);
    const rawModel = toNonEmptyString(parsed.model);
    if (parsed.provider) {
      const canonical = resolveCanonicalProviderModel(parsed.provider, rawModel);
      return {
        provider: canonical.provider,
        model: toNonEmptyString(canonical.model),
        rawModel,
        lookupKey: input,
      };
    }

    return {
      provider: null,
      model: rawModel,
      rawModel,
      lookupKey: input,
    };
  }

  const rawProvider = toNonEmptyString(input.provider);
  const rawModel = toNonEmptyString(input.model);
  if (rawProvider) {
    const canonical = resolveCanonicalProviderModel(rawProvider, rawModel);
    return {
      provider: canonical.provider,
      model: toNonEmptyString(canonical.model),
      rawModel,
      lookupKey: rawModel ? `${canonical.provider}/${rawModel}` : canonical.provider,
    };
  }

  return {
    provider: null,
    model: rawModel,
    rawModel,
    lookupKey: rawModel || "",
  };
}

function heuristicToolCalling(modelStr: string): boolean {
  const normalized = String(modelStr || "").toLowerCase();
  if (!normalized) return false;
  const blocked = TOOL_CALLING_UNSUPPORTED_PATTERNS.some((pattern) => {
    if (normalized === pattern) return true;
    if (normalized.endsWith(`/${pattern}`)) return true;
    return normalized.includes(pattern);
  });
  return !blocked;
}

function heuristicReasoning(modelStr: string): boolean {
  const normalized = String(modelStr || "").toLowerCase();
  if (!normalized) return true;
  const blocked = REASONING_UNSUPPORTED_PATTERNS.some(
    (pattern) =>
      normalized === pattern || normalized.endsWith(`/${pattern}`) || normalized.includes(pattern)
  );
  return !blocked;
}

function heuristicMaxTokens(modelStr: string): boolean {
  const normalized = String(modelStr || "").toLowerCase();
  if (!normalized) return true;
  const blocked = MAX_TOKENS_UNSUPPORTED_PATTERNS.some(
    (pattern) =>
      normalized === pattern || normalized.endsWith(`/${pattern}`) || normalized.includes(pattern)
  );
  return !blocked;
}

/** Last path segment of a path-shaped model id (`cline-pass/kimi-k3` → `kimi-k3`). */
function leafModelId(modelId: string | null | undefined): string | null {
  if (!modelId || !modelId.includes("/")) return null;
  const leaf = modelId.split("/").filter(Boolean).pop() ?? null;
  return leaf && leaf !== modelId ? leaf : null;
}

function getStaticSpec(modelId: string | null, rawModel: string | null): ModelSpec | undefined {
  if (modelId) {
    const byCanonical = getModelSpec(modelId);
    if (byCanonical) return byCanonical;
  }
  if (rawModel && rawModel !== modelId) {
    return getModelSpec(rawModel);
  }
  return undefined;
}

/**
 * #8032: vision-only leaf fallback for path-shaped routed ids.
 *
 * Must NOT live in getStaticSpec() — that helper also feeds supportsTools /
 * supportsThinking / contextWindow / maxOutputTokens. A shared leaf lookup
 * incorrectly promotes e.g. aihorde/deepseek/deepseek-v4-flash to the real
 * DeepSeek V4 Flash tool-calling spec (#8212 regression).
 */
function getVisionStaticSpec(
  modelId: string | null,
  rawModel: string | null
): ModelSpec | undefined {
  const direct = getStaticSpec(modelId, rawModel);
  if (direct) return direct;
  for (const candidate of [modelId, rawModel]) {
    const leaf = leafModelId(candidate);
    if (!leaf) continue;
    const byLeaf = getModelSpec(leaf);
    if (byLeaf) return byLeaf;
  }
  return undefined;
}

function getAuthoritativeStaticContextWindow(
  provider: string | null,
  modelId: string | null,
  rawModel: string | null
): number | null {
  for (const candidate of [modelId, rawModel]) {
    const providerContextWindow = getAuthoritativeProviderContextWindow(provider, candidate);
    if (typeof providerContextWindow === "number") return providerContextWindow;
  }
  for (const candidate of [modelId, rawModel]) {
    const contextWindow = getAuthoritativeContextWindow(candidate);
    if (typeof contextWindow === "number") return contextWindow;
  }
  return null;
}

// #8697-adjacent: this used to rescan Object.entries(MODEL_SPECS) per candidate per
// call — the top hotspot in a full catalog-rebuild profile once the pricing-path and
// getCanonicalModelSpecId() bottlenecks were fixed. Reuses the lazy index already built
// for getCanonicalModelSpecId() (@/shared/constants/modelSpecs) instead of duplicating a
// second cache over the same static table.
function getStaticSpecCanonicalModelId(modelId: string | null, rawModel: string | null) {
  const candidates = [modelId, rawModel].filter(
    (candidate): candidate is string => typeof candidate === "string" && candidate.length > 0
  );
  for (const candidate of candidates) {
    const hit = findModelSpecIdByExactOrAlias(candidate);
    if (hit) return hit;
  }
  return null;
}

/**
 * Strip a trailing `-latest` alias suffix from a model id (#4073). Returns the
 * short id (`pixtral-12b-latest` → `pixtral-12b`) or `null` when there is no
 * `-latest` suffix to drop. Used only as a last-resort synced-lookup fallback.
 */
function stripLatestAlias(modelId: string | null): string | null {
  if (!modelId) return null;
  const stripped = modelId.replace(/-latest$/i, "");
  return stripped && stripped !== modelId ? stripped : null;
}

// #8697-adjacent: MODELS_DEV_PROVIDER_MAP is a static module constant, so the result
// of reverseModelsDevProviders() never changes for a given provider — memoized by
// provider key instead of rescanning Object.entries(MODELS_DEV_PROVIDER_MAP) on every
// call (called once per model in a catalog rebuild). Never evicted — bounded by the
// number of distinct providers ever queried (~50-100 in practice), negligible memory.
const reverseModelsDevProvidersCache = new Map<string, readonly string[]>();

function reverseModelsDevProviders(provider: string): readonly string[] {
  // models.dev may store capabilities under a different OmniRoute provider id
  // that also maps from the same upstream models.dev provider. Build reverse
  // candidates from MODELS_DEV_PROVIDER_MAP (e.g. openai ↔ cx).
  //
  // MODELS_DEV_PROVIDER_MAP's RHS is inconsistent: most providers list their
  // canonical id directly, but the OAuth CLI providers (codex/claude) only
  // list their alias (cx/cc), never the canonical id. Also probe the
  // provider's alias so a canonical id like "codex"/"claude" still matches
  // the map entries keyed only by "cx"/"cc" (#8429).
  const cached = reverseModelsDevProvidersCache.get(provider);
  if (cached) return cached;

  const out = new Set<string>();
  const providerAlias = PROVIDER_ID_TO_ALIAS[provider] || provider;
  for (const [modelsDevId, omniIds] of Object.entries(MODELS_DEV_PROVIDER_MAP)) {
    if (
      omniIds.includes(provider) ||
      omniIds.includes(providerAlias) ||
      modelsDevId === provider ||
      modelsDevId === providerAlias
    ) {
      out.add(modelsDevId);
      for (const id of omniIds) out.add(id);
    }
  }
  // Frozen: the result is now shared across every future call for this provider (via
  // the cache above) instead of a fresh array per call — freeze prevents an accidental
  // caller mutation (e.g. .push()) from corrupting the cache for everyone else.
  const result = Object.freeze([...out]);
  reverseModelsDevProvidersCache.set(provider, result);
  return result;
}

function getSyncedCapabilityForResolved(
  provider: string | null,
  model: string | null,
  rawModel: string | null
): SyncedCapabilities {
  if (!provider || !model) return null;

  const modelCandidates = Array.from(
    new Set(
      [model, rawModel, getStaticSpecCanonicalModelId(model, rawModel)]
        .filter((value): value is string => typeof value === "string" && value.length > 0)
        .flatMap((candidate) => {
          const values = [candidate];
          const stripped = stripLatestAlias(candidate);
          if (stripped) values.push(stripped);
          const leaf = leafModelId(candidate);
          if (leaf) values.push(leaf);
          // models.dev often stores OpenAI-family specialty models as qualified
          // ids under another mapped provider, e.g. vercel + "openai/whisper-1".
          if (!candidate.includes("/")) {
            values.push(`${provider}/${candidate}`);
          }
          return values;
        })
    )
  );

  // Include common host providers that re-publish OpenAI specialty models under
  // qualified ids (observed: vercel/openai/whisper-1, vercel/openai/tts-1).
  const providerCandidates = Array.from(
    new Set([provider, ...reverseModelsDevProviders(provider), "vercel"])
  );

  for (const prov of providerCandidates) {
    for (const mid of modelCandidates) {
      const found = getSyncedCapability(prov, mid);
      if (found) return found;
    }
  }
  return null;
}

/**
 * Last-resort vision fallback in resolveVisionCapability when there is no
 * synced/registry/spec capability data (e.g. Mistral Pixtral, which ships no
 * models.dev `attachment` flag and no registry `supportsVision`). Delegates to
 * the single shared source (`@/shared/constants/visionModels`, #4072) so routing,
 * the `/v1/models` listing and lite compression can never disagree on whether a
 * model is vision-capable. The list is intentionally conservative — a false
 * positive would let an image request route to a text-only model.
 */
export function modelIdLikelyVision(modelId: string | null | undefined): boolean {
  return isVisionModelId(modelId);
}

/**
 * Models that upstream catalogs (notably models.dev) mislabel as vision-capable but
 * are TEXT-ONLY per the vendor's own docs. Listed here so a wrong synced
 * `attachment:true` cannot route an image request to a blind model (the #4071 failure
 * mode). Keep this list tiny and doc-backed.
 *
 * Xiaomi MiMo: only `mimo-v2.5` and `mimo-v2-omni` accept images; the `*-pro` chat
 * models are text-only (mimo.mi.com .../image-understanding; hermes-agent#18884).
 * Anchored to the full id (`$`) and tolerant of a `provider/` prefix so `mimo-v2.5-pro`
 * never matches the multimodal `mimo-v2.5`, and `mimo-v2-pro` never matches `mimo-v2-omni`.
 */
const KNOWN_TEXT_ONLY_DESPITE_SYNC: readonly RegExp[] = [
  /(?:^|\/)mimo-v2\.5-pro$/i,
  /(?:^|\/)mimo-v2-pro$/i,
];

function isKnownTextOnlyDespiteSync(modelId: string | null | undefined): boolean {
  if (!modelId) return false;
  const id = String(modelId);
  return KNOWN_TEXT_ONLY_DESPITE_SYNC.some((pattern) => pattern.test(id));
}

/** True when a modality list declares image and/or video input/output. */
function modalitiesDeclareVision(modalities: readonly string[]): boolean {
  return modalities.some((entry) => {
    const lower = String(entry).toLowerCase();
    return lower.includes("image") || lower.includes("video");
  });
}

function resolveVisionCapability(
  spec: ModelSpec | undefined,
  registryModel: { supportsVision?: boolean } | null,
  synced: SyncedCapabilities,
  modalitiesInput: string[],
  modalitiesOutput: string[],
  modelId?: string
): boolean | null {
  const allModalities = [...modalitiesInput, ...modalitiesOutput].map((entry) =>
    String(entry).toLowerCase()
  );

  // Hard override FIRST: a wrong synced `attachment:true` (or image modality) must not
  // win for models the vendor documents as text-only. Beats every branch below so an
  // image request can never be routed to a blind model (#4071).
  if (isKnownTextOnlyDespiteSync(modelId)) return false;

  if (typeof synced?.attachment === "boolean") {
    // #8250: models.dev sometimes ships attachment=false alongside image/video
    // modalities (observed for Kimi K3). Prefer the richer modality signal over
    // the contradictory false flag so supportsVision / attachment / modalities
    // can be reconciled to a single vision-capable verdict.
    if (synced.attachment === false && modalitiesDeclareVision(allModalities)) {
      return true;
    }
    // #8032: attachment=false without modalities must not beat authoritative
    // registry/spec vision for path-shaped custom/routed ids (e.g. Cline Pass
    // `cp/cline-pass/kimi-k3` → MODEL_SPECS["kimi-k3"].supportsVision).
    if (synced.attachment === false) {
      if (registryModel?.supportsVision === true) return true;
      if (spec?.supportsVision === true) return true;
      return false;
    }
    return synced.attachment;
  }

  if (allModalities.some((entry) => entry.includes("image"))) {
    return true;
  }

  if (allModalities.length > 0) {
    return false;
  }

  if (typeof registryModel?.supportsVision === "boolean") return registryModel.supportsVision;
  if (typeof spec?.supportsVision === "boolean") return spec.supportsVision;

  // Last resort: no capability data at all. Positively confirm known multimodal
  // families by model id so image requests can be routed to them; everything
  // else stays `null` (unknown).
  if (modelIdLikelyVision(modelId)) return true;

  return null;
}

/**
 * Issue #6524: an operator-set `max_output_tokens` capability override (see
 * `src/lib/db/modelCapabilityOverrides.ts`) is the manual escape hatch for a
 * wrong/stale synced `limit_output` value (e.g. a provider's models.dev catalog
 * row reporting `limit_output` equal to `limit_context`). It already won over the
 * synced value in `getResolvedModelCapabilities().maxOutputTokens` — this helper
 * makes `getExplicitModelOutputCap()` (used by the reasoning-token-buffer clamp)
 * consult the same override so both read paths agree.
 */
/**
 * Exact-match capability override lookup with intentional raw-alias fallback.
 *
 * An override may be stored under either the canonical model id or the exact
 * provider-scoped raw alias the operator used (e.g. `github/claude-opus-4.5`
 * resolving to canonical `claude-opus-4-5-20251101`). We consult the canonical
 * id first, then the raw alias — both are exact provider/model matches. There is
 * deliberately NO suffix/effort/family inheritance: an override for
 * `codex/gpt-5.6` never applies to `codex/gpt-5.6-high`.
 */
function getCapabilityOverride(
  resolved: { provider: string | null; model: string | null; rawModel: string | null },
  key: "max_input_tokens" | "max_output_tokens"
): number | null {
  const canonical = getModelCapabilityOverride(resolved.provider, resolved.model, key);
  if (canonical !== null) return canonical;
  return resolved.rawModel && resolved.rawModel !== resolved.model
    ? getModelCapabilityOverride(resolved.provider, resolved.rawModel, key)
    : null;
}

function getContextOverride(resolved: {
  provider: string | null;
  model: string | null;
  rawModel: string | null;
}): number | null {
  const canonical = getModelContextOverride(resolved.provider, resolved.model);
  if (canonical !== null) return canonical;
  return resolved.rawModel && resolved.rawModel !== resolved.model
    ? getModelContextOverride(resolved.provider, resolved.rawModel)
    : null;
}

/**
 * Resolve a persisted context override by canonical id, then by the exact raw
 * alias supplied by the caller. Neither lookup inherits to related models.
 */
export function getResolvedModelContextOverride(input: CapabilityInput): number | null {
  return getContextOverride(resolveCapabilityInput(input));
}

function getInputTokenCapabilityOverride(resolved: {
  provider: string | null;
  model: string | null;
  rawModel: string | null;
}): number | null {
  return getCapabilityOverride(resolved, "max_input_tokens");
}

function getOutputTokenCapabilityOverride(resolved: {
  provider: string | null;
  model: string | null;
  rawModel: string | null;
}): number | null {
  return getCapabilityOverride(resolved, "max_output_tokens");
}

export function getExplicitModelOutputCap(input: CapabilityInput): number | null {
  const resolved = resolveCapabilityInput(input);
  const maxTokenOverride = getOutputTokenCapabilityOverride(resolved);
  if (maxTokenOverride !== null) return maxTokenOverride;

  const synced = getSyncedCapabilityForResolved(
    resolved.provider,
    resolved.model,
    resolved.rawModel
  );
  if (synced && typeof synced.limit_output === "number") return synced.limit_output;

  const registryModel = getRegistryModel(resolved.provider, resolved.model);
  if (typeof registryModel?.maxOutputTokens === "number") return registryModel.maxOutputTokens;

  const spec = getStaticSpec(resolved.model, resolved.rawModel);
  return spec?.maxOutputTokens ?? null;
}

export function getResolvedModelCapabilities(
  input: CapabilityInput,
  options?: ResolveModelCapabilitiesOptions
): ResolvedModelCapabilities {
  // Reconciliation / auto-discovery needs the override-free catalog view so a
  // persisted override never feeds back into the comparison that (re)writes it.
  const usePersistedOverrides = options?.persistedOverrides !== false;
  const resolved = resolveCapabilityInput(input);
  const spec = getStaticSpec(resolved.model, resolved.rawModel);
  const registryModel = getRegistryModel(resolved.provider, resolved.model);
  const synced = getSyncedCapabilityForResolved(
    resolved.provider,
    resolved.model,
    resolved.rawModel
  );

  const modalitiesInput = parseModalities(synced?.modalities_input);
  const modalitiesOutput = parseModalities(synced?.modalities_output);
  const lookupKey =
    toNonEmptyString(
      resolved.provider && resolved.model
        ? `${resolved.provider}/${resolved.model}`
        : resolved.model || resolved.rawModel || resolved.lookupKey
    ) || "";
  const reasoningDenied = !heuristicReasoning(lookupKey);

  // Provider-level fallback: a live-discovered model (passthroughModels
  // providers like AI Horde) has no per-model registry entry, synced
  // capability, or static spec — every source above resolves to null, so
  // toolCalling would otherwise fall through to heuristicToolCalling's
  // optimistic default (true). Reuse the same unsupportedParams signal the
  // request-time strip already relies on: if the provider declares "tools"
  // unsupported for every model it serves, that's authoritative here too.
  const providerDeniesTools =
    resolved.provider && resolved.model
      ? getUnsupportedParams(resolved.provider, resolved.model).includes("tools")
      : false;

  const supportsTools =
    synced?.tool_call ??
    (typeof registryModel?.toolCalling === "boolean" ? registryModel.toolCalling : null) ??
    (typeof spec?.supportsTools === "boolean" ? spec.supportsTools : null) ??
    (providerDeniesTools ? false : null);

  const supportsThinking = reasoningDenied
    ? false
    : (synced?.reasoning ??
      (typeof registryModel?.supportsReasoning === "boolean"
        ? registryModel.supportsReasoning
        : null) ??
      (typeof spec?.supportsThinking === "boolean" ? spec.supportsThinking : null));

  const authoritativeContextWindow = getAuthoritativeStaticContextWindow(
    resolved.provider,
    resolved.model,
    resolved.rawModel
  );
  // A persisted context-window override (operator-set or auto-discovered)
  // reflects the real *total* window and wins over every static/synced source.
  // `maxInputTokens` still follows its own precedence chain; only when that
  // chain has no narrower source does it naturally fall back to this window.
  const persistedContextWindow = usePersistedOverrides ? getContextOverride(resolved) : null;
  const contextWindow =
    persistedContextWindow ??
    authoritativeContextWindow ??
    synced?.limit_context ??
    (typeof registryModel?.contextLength === "number" ? registryModel.contextLength : null) ??
    spec?.contextWindow ??
    null;

  const maxInputOverride = usePersistedOverrides ? getInputTokenCapabilityOverride(resolved) : null;
  const maxTokenOverride = usePersistedOverrides
    ? getOutputTokenCapabilityOverride(resolved)
    : null;

  // Vision consults leaf static metadata for path-shaped ids; other capability
  // fields keep using the non-leaf `spec` from getStaticSpec() above.
  const visionSpec = getVisionStaticSpec(resolved.model, resolved.rawModel);

  const supportsVision = resolveVisionCapability(
    visionSpec,
    registryModel,
    synced,
    modalitiesInput,
    modalitiesOutput,
    lookupKey
  );

  // #8250: when resolve promoted vision over a contradictory attachment=false,
  // expose attachment=true so catalog / Vision Bridge / clients see one verdict.
  let attachment = synced?.attachment ?? null;
  if (supportsVision === true && attachment === false) {
    attachment = true;
  }

  return {
    provider: resolved.provider,
    model: resolved.model,
    rawModel: resolved.rawModel,
    toolCalling: supportsTools ?? heuristicToolCalling(lookupKey),
    reasoning: supportsThinking ?? heuristicReasoning(lookupKey),
    supportsThinking,
    supportsTools,
    supportsVision,
    supportsMaxTokens: heuristicMaxTokens(lookupKey),
    attachment,
    structuredOutput: synced?.structured_output ?? null,
    temperature: synced?.temperature ?? null,
    contextWindow,
    maxInputTokens: (() => {
      // Input cap is input-only. An explicit `max_input_tokens` override wins;
      // otherwise fall back to the existing per-source input limits, then to the
      // total window. The effective cap can never exceed the total window
      // (input + output), so clamp it — but never double-count a requested
      // output against this input cap.
      const candidate =
        maxInputOverride ??
        (typeof registryModel?.maxInputTokens === "number" ? registryModel.maxInputTokens : null) ??
        authoritativeContextWindow ??
        synced?.limit_input ??
        contextWindow;
      return candidate !== null && contextWindow !== null
        ? Math.min(candidate, contextWindow)
        : candidate;
    })(),
    maxOutputTokens:
      maxTokenOverride ??
      synced?.limit_output ??
      (typeof registryModel?.maxOutputTokens === "number" ? registryModel.maxOutputTokens : null) ??
      spec?.maxOutputTokens ??
      null,
    defaultThinkingBudget: spec?.defaultThinkingBudget ?? 0,
    thinkingBudgetCap: spec?.thinkingBudgetCap ?? null,
    thinkingOverhead: spec?.thinkingOverhead ?? null,
    adaptiveMaxTokens: spec?.adaptiveMaxTokens ?? null,
    family: synced?.family ?? null,
    status: synced?.status ?? null,
    openWeights: synced?.open_weights ?? null,
    knowledgeCutoff: synced?.knowledge_cutoff ?? null,
    releaseDate: synced?.release_date ?? null,
    lastUpdated: synced?.last_updated ?? null,
    modalitiesInput,
    modalitiesOutput,
    interleavedField:
      synced?.interleaved_field ??
      (typeof registryModel?.interleavedField === "string" ? registryModel.interleavedField : null),
  };
}

/**
 * Input cap enforced at the request-time hard gate, with explicit combo semantics.
 *
 * Feature 5004 lets a raw, exact `model_context_overrides` entry supersede a
 * deliberately smaller catalog/client input hint for COMBO routing: the combo
 * compatibility filter (`open-sse/services/combo/contextOverrideGate.ts`) already
 * rescues such targets, so the final hard gate in handleChatCore must not turn
 * around and reject the rescued target on the very hint the filter bypassed.
 *
 * Semantics (deliberately narrow — NO suffix/effort/family inheritance):
 * - An explicit `max_input_tokens` capability override is ALWAYS enforced, for
 *   direct and combo requests alike. It is the operator's input-only ceiling and
 *   must never be bypassed by a context-window override.
 * - Otherwise, for a COMBO request with an exact persisted context override, that
 *   context override is the input cap (it reflects the real window; the smaller
 *   catalog hint does not apply). Direct requests ignore this branch.
 * - Otherwise the canonical `maxInputTokens` chain applies (registry input hint →
 *   authoritative window → synced limit_input → total window), clamped to the
 *   total window.
 *
 * `isCombo` selects the combo-rescue branch; pass `false`/omit for direct calls.
 * The returned cap is still only an *input* bound — the total-window/output
 * reserve check is enforced separately by `enforceOutputTokenBudget`.
 */
export function resolveInputTokenCapForGate(
  input: CapabilityInput,
  { isCombo = false }: { isCombo?: boolean } = {}
): number | null {
  const resolved = resolveCapabilityInput(input);

  // 1. An explicit `max_input_tokens` override always wins and is never bypassed.
  const explicitInputOverride = getInputTokenCapabilityOverride(resolved);
  if (explicitInputOverride !== null) return explicitInputOverride;

  // 2. Combo rescue: an exact persisted context override supersedes the smaller
  //    catalog/client input hint (mirrors contextOverrideGate.evaluateContextLimit).
  if (isCombo) {
    const contextOverride = getContextOverride(resolved);
    if (contextOverride !== null) return contextOverride;
  }

  // 3. Canonical chain (already clamped to the total window by the resolver).
  return getResolvedModelCapabilities(input).maxInputTokens;
}

export function supportsToolCalling(input: CapabilityInput): boolean {
  if (typeof input === "string" && !String(input || "").trim()) return false;
  return getResolvedModelCapabilities(input).toolCalling;
}

export function supportsReasoning(input: CapabilityInput): boolean {
  if (typeof input === "string" && !String(input || "").trim()) return true;
  return getResolvedModelCapabilities(input).reasoning;
}

export function supportsMaxTokens(input: CapabilityInput): boolean {
  if (typeof input === "string" && !String(input || "").trim()) return true;
  return getResolvedModelCapabilities(input).supportsMaxTokens;
}

export function capMaxOutputTokens(input: CapabilityInput, requested?: number): number | null {
  const cap = getResolvedModelCapabilities(input).maxOutputTokens;
  const hasRequested = typeof requested === "number" && Number.isFinite(requested);
  if (cap === null) return hasRequested ? requested : null;
  return hasRequested ? Math.min(requested, cap) : cap;
}

export function getDefaultThinkingBudget(input: CapabilityInput): number {
  return getResolvedModelCapabilities(input).defaultThinkingBudget;
}

/**
 * Clamp a requested thinking budget to the model's real ceiling.
 *
 * Resolution order (lowest wins):
 *  1. Registry cap (MODEL_SPECS.thinkingBudgetCap) — authoritative when present.
 *  2. Learned cap — a lower ceiling previously discovered via an upstream 400
 *     ("thinking_budget must be in the range ...") recorded by the executor
 *     (open-sse/services/learnedThinkingCaps.ts). In-memory, per provider+model.
 *  3. Gemini-family fallback — when the registry has no cap but the model id
 *     contains "gemini" (any provider: many providers host Gemini models), clamp
 *     to GEMINI_FALLBACK_THINKING_CAP (32768, the known pro-tier cap) instead of
 *     letting an xhigh budget (131072) sail through to a 400. Registered flash
 *     models already carry their explicit 24576 cap via rule 1, so this only
 *     fires for unregistered Gemini ids.
 */
export function capThinkingBudget(input: CapabilityInput, budget: number): number {
  const resolved = getResolvedModelCapabilities(input);
  let cap = resolved.thinkingBudgetCap;

  const modelId = resolved.model ?? resolved.rawModel ?? "";
  const modelLower = modelId.toLowerCase();
  // Learned-cap lookup needs a concrete provider key (the executor records under
  // `this.provider`). When the input is a bare Gemini id, `resolved.provider` is
  // null — but bare Gemini ids always route to the native Gemini provider, so
  // default to "gemini". Without this a cap learned via the executor would be
  // invisible to bare-model callers. Provider-qualified inputs keep their own
  // provider, preserving per-provider independence.
  const providerForLearned = resolved.provider ?? (modelLower.includes("gemini") ? "gemini" : null);

  const learned = getLearnedThinkingCap(providerForLearned, modelId);
  if (learned !== null) {
    cap = cap === null ? learned : Math.min(cap, learned);
  }

  if (cap === null && modelLower.includes("gemini")) {
    cap = GEMINI_FALLBACK_THINKING_CAP;
  }

  return Math.min(budget, cap ?? budget);
}

export function getModelContextLimit(
  providerOrInput: CapabilityInput,
  modelId?: string
): number | null {
  const resolved =
    typeof providerOrInput === "string" && modelId !== undefined
      ? getResolvedModelCapabilities({ provider: providerOrInput, model: modelId })
      : getResolvedModelCapabilities(providerOrInput);
  return resolved.contextWindow;
}