/**
 * db/models.ts — Custom models, synced available models, and model-flag queries.
 * Compat overrides, model aliases, and MITM aliases have moved to sub-modules under
 * models/; this file re-exports their public APIs for backward compatibility.
 */

import { isRetiredGitHubCopilotModelId } from "@omniroute/open-sse/config/providers/registry/github/retiredModels.ts";

import { getDbInstance } from "./core";
import { backupDbFile } from "./backup";
import { getProviderConnectionsCount } from "./providers";
import { type JsonRecord, getKeyValue } from "./models/shared";
import {
  normalizeSyncedAvailableModels,
  type SyncedAvailableModel,
  type SyncedAvailableModelInput,
} from "./models/synced";
import {
  readCompatList,
  writeCompatList,
  deepMergeCompatByProtocol,
  compatByProtocolHasEntries,
  isCompatProtocolKey,
  sanitizeUpstreamHeadersMap,
  removeModelCompatOverride,
  type CompatByProtocolMap,
  type ModelCompatProtocolKey,
  type ModelCompatOverride,
  type ModelCompatPerProtocol,
} from "./models/compat";

export {
  sanitizeUpstreamHeadersMap,
  getModelCompatOverrides,
  mergeModelCompatOverride,
  removeModelCompatOverride,
  MODEL_COMPAT_PROTOCOL_KEYS,
  type ModelCompatProtocolKey,
  type ModelCompatPerProtocol,
  type ModelCompatOverride,
  type ModelCompatPatch,
} from "./models/compat";
export {
  getModelAliases,
  setModelAlias,
  deleteModelAlias,
  deleteModelAliasesForProvider,
} from "./models/aliases";
export { getMitmAlias, setMitmAliasAll } from "./models/mitmAlias";
export type { SyncedAvailableModel } from "./models/synced";

// ──────────────── Custom Models ────────────────

export async function getCustomModels(providerId?: string) {
  const db = getDbInstance();
  if (providerId) {
    const row = db
      .prepare("SELECT value FROM key_value WHERE namespace = 'customModels' AND key = ?")
      .get(providerId);
    const value = getKeyValue(row).value;
    return value ? JSON.parse(value) : [];
  }
  const rows = db
    .prepare("SELECT key, value FROM key_value WHERE namespace = 'customModels'")
    .all();
  const result: Record<string, unknown> = {};
  for (const row of rows) {
    const { key, value } = getKeyValue(row);
    if (!key || value === null) continue;
    result[key] = JSON.parse(value);
  }
  return result;
}

export async function getAllCustomModels() {
  const db = getDbInstance();
  const rows = db
    .prepare("SELECT key, value FROM key_value WHERE namespace = 'customModels'")
    .all();
  const result: Record<string, unknown> = {};
  for (const row of rows) {
    const { key, value } = getKeyValue(row);
    if (!key || value === null) continue;
    result[key] = JSON.parse(value);
  }
  return result;
}

export async function addCustomModel(
  providerId: string,
  modelId: string,
  modelName?: string,
  source = "manual",
  apiFormat:
    | "chat-completions"
    | "responses"
    | "embeddings"
    | "rerank"
    | "audio-transcriptions"
    | "audio-speech"
    | "images-generations" = "chat-completions",
  supportedEndpoints: string[] = ["chat"],
  // #2905: optional per-model wire format override (e.g. "claude" for an
  // opencode-go custom model). When unset, routing falls back to the provider
  // default format.
  targetFormat?: string,
  // #1294: optional per-model token limits supplied from the "add custom model"
  // form. Persisted under the same keys the /v1/models catalog reads back.
  tokenLimits: { inputTokenLimit?: number; outputTokenLimit?: number } = {},
  // #1904: optional manual vision-capability override for the "add custom model"
  // form — read back by getCustomVisionCapabilityFields() in the /v1/models catalog.
  supportsVision?: boolean
) {
  const db = getDbInstance();
  const row = db
    .prepare("SELECT value FROM key_value WHERE namespace = 'customModels' AND key = ?")
    .get(providerId);
  const value = getKeyValue(row).value;
  const models = value ? JSON.parse(value) : [];

  const exists = models.find((m: JsonRecord) => m.id === modelId);
  if (exists) return exists;

  const model = {
    id: modelId,
    name: modelName || modelId,
    source,
    apiFormat,
    supportedEndpoints,
    ...(targetFormat ? { targetFormat } : {}),
    ...(tokenLimits.inputTokenLimit != null
      ? { inputTokenLimit: tokenLimits.inputTokenLimit }
      : {}),
    ...(tokenLimits.outputTokenLimit != null
      ? { outputTokenLimit: tokenLimits.outputTokenLimit }
      : {}),
    ...(typeof supportsVision === "boolean" ? { supportsVision } : {}),
  };
  models.push(model);
  db.prepare(
    "INSERT OR REPLACE INTO key_value (namespace, key, value) VALUES ('customModels', ?, ?)"
  ).run(providerId, JSON.stringify(models));
  backupDbFile("pre-write");
  return model;
}

/**
 * Replace the entire custom models list for a provider.
 * Preserves per-model compatibility overrides for models that still exist.
 */
export async function replaceCustomModels(
  providerId: string,
  models: Array<{
    id: string;
    name?: string;
    source?: string;
    apiFormat?: string;
    supportedEndpoints?: string[];
    inputTokenLimit?: number;
    outputTokenLimit?: number;
    description?: string;
    supportsThinking?: boolean;
    targetFormat?: string;
  }>,
  { allowEmpty = false }: { allowEmpty?: boolean } = {}
) {
  // Guard: skip destructive clear when the caller hasn't explicitly opted in.
  // This prevents callers from wiping manually added models when the
  // upstream /models endpoint fails, times out, or returns an empty list.
  if (models.length === 0 && !allowEmpty) {
    const existing = await getCustomModels(providerId);
    return Array.isArray(existing) ? existing : [];
  }

  const db = getDbInstance();
  const existing = await getCustomModels(providerId);
  const existingMap = new Map<string, JsonRecord>();
  if (Array.isArray(existing)) {
    for (const m of existing) {
      if (m && typeof m === "object" && m.id) existingMap.set(m.id, m);
    }
  }

  // Merge: keep existing per-model compat flags if model still exists
  const merged = models.map((m) => {
    const prev = existingMap.get(m.id);
    return {
      id: m.id,
      name: m.name || m.id,
      source: m.source || "auto-sync",
      apiFormat: m.apiFormat || (prev as any)?.apiFormat || "chat-completions",
      supportedEndpoints: m.supportedEndpoints || (prev as any)?.supportedEndpoints || ["chat"],
      // #2905: preserve a per-model targetFormat override (new value wins, else prev).
      ...(m.targetFormat
        ? { targetFormat: m.targetFormat }
        : (prev as any)?.targetFormat
          ? { targetFormat: (prev as any).targetFormat }
          : {}),
      // Preserve metadata from provider API (or previous sync)
      ...(m.inputTokenLimit != null
        ? { inputTokenLimit: m.inputTokenLimit }
        : (prev as any)?.inputTokenLimit != null
          ? { inputTokenLimit: (prev as any).inputTokenLimit }
          : {}),
      ...(m.outputTokenLimit != null
        ? { outputTokenLimit: m.outputTokenLimit }
        : (prev as any)?.outputTokenLimit != null
          ? { outputTokenLimit: (prev as any).outputTokenLimit }
          : {}),
      ...(m.description != null
        ? { description: m.description }
        : (prev as any)?.description != null
          ? { description: (prev as any).description }
          : {}),
      ...(m.supportsThinking != null
        ? { supportsThinking: m.supportsThinking }
        : (prev as any)?.supportsThinking != null
          ? { supportsThinking: (prev as any).supportsThinking }
          : {}),
      // Preserve existing compat flags
      ...(prev && (prev as any).normalizeToolCallId !== undefined
        ? { normalizeToolCallId: (prev as any).normalizeToolCallId }
        : {}),
      ...(prev && (prev as any).preserveOpenAIDeveloperRole !== undefined
        ? { preserveOpenAIDeveloperRole: (prev as any).preserveOpenAIDeveloperRole }
        : {}),
      ...(prev && (prev as any).compatByProtocol
        ? { compatByProtocol: (prev as any).compatByProtocol }
        : {}),
      ...(prev && (prev as any).upstreamHeaders
        ? { upstreamHeaders: (prev as any).upstreamHeaders }
        : {}),
    };
  });

  if (merged.length === 0) {
    db.prepare("DELETE FROM key_value WHERE namespace = 'customModels' AND key = ?").run(
      providerId
    );
  } else {
    db.prepare(
      "INSERT OR REPLACE INTO key_value (namespace, key, value) VALUES ('customModels', ?, ?)"
    ).run(providerId, JSON.stringify(merged));
  }

  backupDbFile("pre-write");
  return merged;
}

/**
 * Remove provider-level models created by discovery/import while preserving
 * models the user added manually. Returns the removed model IDs.
 */
export async function deleteImportedCustomModels(providerId: string): Promise<string[]> {
  const db = getDbInstance();
  const row = db
    .prepare("SELECT value FROM key_value WHERE namespace = 'customModels' AND key = ?")
    .get(providerId);
  const value = getKeyValue(row).value;
  if (!value) return [];

  const parsed = JSON.parse(value);
  if (!Array.isArray(parsed)) return [];

  const removed: JsonRecord[] = [];
  const retained = parsed.filter((model: JsonRecord) => {
    const source = typeof model?.source === "string" ? model.source.trim().toLowerCase() : "manual";
    const imported = source === "imported" || source === "api-sync" || source === "auto-sync";
    if (imported) removed.push(model);
    return !imported;
  });
  if (removed.length === 0) return [];

  if (retained.length === 0) {
    db.prepare("DELETE FROM key_value WHERE namespace = 'customModels' AND key = ?").run(
      providerId
    );
  } else {
    db.prepare("UPDATE key_value SET value = ? WHERE namespace = 'customModels' AND key = ?").run(
      JSON.stringify(retained),
      providerId
    );
  }

  const removedIds = removed.flatMap((model) =>
    typeof model.id === "string" && model.id ? [model.id] : []
  );
  for (const modelId of removedIds) removeModelCompatOverride(providerId, modelId);
  backupDbFile("pre-write");
  return removedIds;
}

export async function removeCustomModel(providerId: string, modelId: string) {
  const db = getDbInstance();
  const row = db
    .prepare("SELECT value FROM key_value WHERE namespace = 'customModels' AND key = ?")
    .get(providerId);
  if (!row) return false;

  const value = getKeyValue(row).value;
  if (!value) return false;
  const models = JSON.parse(value);
  const before = models.length;
  const filtered = models.filter((m: JsonRecord) => m.id !== modelId);

  if (filtered.length === before) return false;

  if (filtered.length === 0) {
    db.prepare("DELETE FROM key_value WHERE namespace = 'customModels' AND key = ?").run(
      providerId
    );
  } else {
    db.prepare("UPDATE key_value SET value = ? WHERE namespace = 'customModels' AND key = ?").run(
      JSON.stringify(filtered),
      providerId
    );
  }

  removeModelCompatOverride(providerId, modelId);
  backupDbFile("pre-write");
  return true;
}

// ──────────────── Synced Available Models ────────────────
// Storage: namespace = 'syncedAvailableModels', key = '<providerId>:<connectionId>'
// Each connection stores its own model list. Reads union across all connections
// for a provider. Deleting a connection removes only its models.

/**
 * Get synced available models for a specific provider connection.
 */
export async function getSyncedAvailableModelsForConnection(
  providerId: string,
  connectionId: string
): Promise<SyncedAvailableModel[]> {
  const db = getDbInstance();
  const key = `${providerId}:${connectionId}`;
  const row = db
    .prepare("SELECT value FROM key_value WHERE namespace = 'syncedAvailableModels' AND key = ?")
    .get(key);
  const value = getKeyValue(row).value;
  if (!value) return [];
  try {
    const models = JSON.parse(value);
    return normalizeSyncedAvailableModels(models, providerId);
  } catch {
    return [];
  }
}

/**
 * Get all synced available models for a provider, unioned across all connections.
 */
export async function getSyncedAvailableModels(
  providerId: string
): Promise<SyncedAvailableModel[]> {
  const db = getDbInstance();
  const rows = db
    .prepare(
      "SELECT key, value FROM key_value WHERE namespace = 'syncedAvailableModels' AND key LIKE ?"
    )
    .all(`${providerId}:%`);
  const map = new Map<string, SyncedAvailableModel>();
  for (const row of rows) {
    const { key, value } = getKeyValue(row);
    if (!key || value === null) continue;
    const models = normalizeSyncedAvailableModels(JSON.parse(value), providerId);
    for (const m of models) {
      if (m.id) map.set(m.id, m);
    }
  }
  return Array.from(map.values());
}

/**
 * Get synced available models for a provider grouped by connection id.
 */
export async function getSyncedAvailableModelsByConnection(
  providerId: string
): Promise<Record<string, SyncedAvailableModel[]>> {
  const db = getDbInstance();
  const prefix = `${providerId}:`;
  const rows = db
    .prepare(
      "SELECT key, value FROM key_value WHERE namespace = 'syncedAvailableModels' AND key LIKE ?"
    )
    .all(`${prefix}%`);
  const result: Record<string, SyncedAvailableModel[]> = {};
  for (const row of rows) {
    const { key, value } = getKeyValue(row);
    if (!key || value === null || !key.startsWith(prefix)) continue;
    try {
      const connectionId = key.slice(prefix.length);
      result[connectionId] = normalizeSyncedAvailableModels(JSON.parse(value), providerId);
    } catch {
      // Ignore malformed legacy entries.
    }
  }
  return result;
}

/**
 * Get all synced available models across all providers.
 */
export async function getAllSyncedAvailableModels(): Promise<
  Record<string, SyncedAvailableModel[]>
> {
  const db = getDbInstance();
  const rows = db
    .prepare("SELECT key, value FROM key_value WHERE namespace = 'syncedAvailableModels'")
    .all();
  // Group by providerId (before the colon)
  const byProvider = new Map<string, Map<string, SyncedAvailableModel>>();
  for (const row of rows) {
    const { key, value } = getKeyValue(row);
    if (!key || value === null) continue;
    const providerId = key.split(":")[0];
    if (!byProvider.has(providerId)) byProvider.set(providerId, new Map());
    const models = normalizeSyncedAvailableModels(JSON.parse(value), providerId);
    const map = byProvider.get(providerId)!;
    for (const m of models) {
      if (m.id) map.set(m.id, m);
    }
  }
  const result: Record<string, SyncedAvailableModel[]> = {};
  for (const [providerId, map] of byProvider) {
    result[providerId] = Array.from(map.values());
  }
  return result;
}

/**
 * Find active providers whose synchronized catalog contains an exact model ID.
 *
 * This keeps request-time inference aligned with the same connection-scoped
 * syncedAvailableModels data used by /v1/models without loading every model list
 * into application memory for each request.
 */
export async function getActiveProvidersWithSyncedModel(modelId: string): Promise<string[]> {
  if (!modelId) return [];

  const db = getDbInstance();
  const rows = db
    .prepare(
      `SELECT DISTINCT pc.provider AS provider
       FROM provider_connections pc
       JOIN key_value kv
         ON kv.namespace = 'syncedAvailableModels'
        AND kv.key = pc.provider || ':' || pc.id
       JOIN json_each(CASE WHEN json_valid(kv.value) THEN kv.value ELSE '[]' END) synced_model
       WHERE pc.is_active = 1
         AND COALESCE(
           json_extract(synced_model.value, '$.id'),
           json_extract(synced_model.value, '$.name'),
           json_extract(synced_model.value, '$.model')
         ) = ?`
    )
    .all(modelId) as Array<{ provider?: unknown }>;

  return rows
    .map((row) => row.provider)
    .filter((provider): provider is string => typeof provider === "string" && provider.length > 0)
    .filter((provider) => !isRetiredGitHubCopilotModelId(provider, modelId));
}

/**
 * Replace the model list for a specific connection.
 * Key format: '<providerId>:<connectionId>'
 */
export async function replaceSyncedAvailableModelsForConnection(
  providerId: string,
  connectionId: string,
  models: SyncedAvailableModelInput[]
): Promise<SyncedAvailableModel[]> {
  const db = getDbInstance();
  const key = `${providerId}:${connectionId}`;
  // #3199: drop ids the operator DELETED (trash) so a re-fetch does not re-import
  // a model that was explicitly removed.
  // #3782: key ONLY on the distinct `isDeleted` marker — NOT on `isHidden`.
  // Eye/visibility-hidden models (`isHidden:true`, no `isDeleted`) must stay in
  // the synced store so they remain listed-but-hidden across re-syncs instead of
  // churning back on through the managed-alias path ("Auto Sync Enabling all
  // Models"). See getModelIsDeleted for the legacy-row caveat.
  const normalizedModels = normalizeSyncedAvailableModels(models, providerId).filter(
    (m) => !getModelIsDeleted(providerId, m.id)
  );
  if (normalizedModels.length === 0) {
    db.prepare("DELETE FROM key_value WHERE namespace = 'syncedAvailableModels' AND key = ?").run(
      key
    );
  } else {
    db.prepare(
      "INSERT OR REPLACE INTO key_value (namespace, key, value) VALUES ('syncedAvailableModels', ?, ?)"
    ).run(key, JSON.stringify(normalizedModels));
  }
  backupDbFile("pre-write");
  // Return the full unioned list for the provider
  return getSyncedAvailableModels(providerId);
}

/**
 * Remove a single synced available model from all connections of a provider.
 * Returns true if the model was found and removed from at least one connection.
 */
export async function removeSyncedAvailableModel(
  providerId: string,
  modelId: string
): Promise<boolean> {
  const db = getDbInstance();
  const prefix = `${providerId}:`;
  const rows = db
    .prepare(
      "SELECT key, value FROM key_value WHERE namespace = 'syncedAvailableModels' AND key LIKE ?"
    )
    .all(`${prefix}%`);

  let removedAny = false;
  const removeModel = db.transaction(() => {
    for (const row of rows) {
      const { key, value } = getKeyValue(row);
      if (!key || value === null) continue;

      let parsedModels: unknown;
      try {
        parsedModels = JSON.parse(value);
      } catch (error) {
        console.warn(`[DB] Skipping malformed syncedAvailableModels entry for key ${key}:`, error);
        continue;
      }

      const models = normalizeSyncedAvailableModels(parsedModels, providerId);
      const filtered = models.filter((m) => m.id !== modelId);
      if (filtered.length !== models.length) {
        removedAny = true;
        if (filtered.length === 0) {
          db.prepare(
            "DELETE FROM key_value WHERE namespace = 'syncedAvailableModels' AND key = ?"
          ).run(key);
        } else {
          db.prepare(
            "UPDATE key_value SET value = ? WHERE namespace = 'syncedAvailableModels' AND key = ?"
          ).run(JSON.stringify(filtered), key);
        }
      }
    }

    if (removedAny) backupDbFile("pre-write");
  });

  removeModel();
  return removedAny;
}

/**
 * Delete all synced models for a specific connection.
 * Returns the remaining unioned list for the provider.
 */
export async function deleteSyncedAvailableModelsForConnection(
  providerId: string,
  connectionId: string
): Promise<SyncedAvailableModel[]> {
  const db = getDbInstance();
  const key = `${providerId}:${connectionId}`;
  db.prepare("DELETE FROM key_value WHERE namespace = 'syncedAvailableModels' AND key = ?").run(
    key
  );
  backupDbFile("pre-write");
  return getSyncedAvailableModels(providerId);
}

/**
 * Clean model state after a provider connection has been deleted. Imported
 * provider-level models are removed only when no sibling connection remains.
 */
export async function cleanupProviderModelsAfterConnectionDelete(
  providerId: string,
  connectionId: string
): Promise<{
  remainingConnections: number;
  removedImportedModelIds: string[];
  remainingSyncedModels: SyncedAvailableModel[];
}> {
  const remainingSyncedModels = await deleteSyncedAvailableModelsForConnection(
    providerId,
    connectionId
  );
  const remainingConnections = getProviderConnectionsCount({ provider: providerId });
  const removedImportedModelIds =
    remainingConnections === 0 ? await deleteImportedCustomModels(providerId) : [];

  return { remainingConnections, removedImportedModelIds, remainingSyncedModels };
}

/**
 * Delete all synced models for every connection belonging to a provider.
 * Returns the number of connection-scoped synced model lists removed.
 */
export async function deleteSyncedAvailableModelsForProvider(providerId: string): Promise<number> {
  const db = getDbInstance();
  const keyPrefix = `${providerId}:`;
  const result = db
    .prepare(
      "DELETE FROM key_value WHERE namespace = 'syncedAvailableModels' AND substr(key, 1, ?) = ?"
    )
    .run(keyPrefix.length, keyPrefix);
  backupDbFile("pre-write");
  return Number(result.changes || 0);
}

/**
 * Prune stale synced available models for a provider, keeping only the specified allowed connection IDs.
 * Returns the number of keys deleted.
 */
export async function pruneStaleSyncedAvailableModelsForProvider(
  providerId: string,
  allowedConnectionIds: string[]
): Promise<number> {
  const db = getDbInstance();
  if (allowedConnectionIds.length === 0) {
    return deleteSyncedAvailableModelsForProvider(providerId);
  }
  const placeholders = allowedConnectionIds.map(() => "?").join(",");
  const keyPrefix = `${providerId}:`;
  const allowedKeys = allowedConnectionIds.map((id) => `${providerId}:${id}`);
  const result = db
    .prepare(
      `DELETE FROM key_value WHERE namespace = 'syncedAvailableModels' AND key LIKE ? AND key NOT IN (${placeholders})`
    )
    .run(`${keyPrefix}%`, ...allowedKeys);
  backupDbFile("pre-write");
  return Number(result.changes || 0);
}

/**
 * Apply a tri-state boolean override from `updates` onto `next`:
 * field absent → keep whatever `next` already carries; explicit `null` → clear
 * the override (callers fall back to their heuristic); anything else → persist
 * the coerced boolean.
 */
function applyTriStateBooleanOverride(
  next: JsonRecord,
  updates: Record<string, unknown>,
  field: string
): void {
  if (!Object.prototype.hasOwnProperty.call(updates, field)) return;
  if (updates[field] === null) {
    delete next[field];
    return;
  }
  next[field] = Boolean(updates[field]);
}

export async function updateCustomModel(
  providerId: string,
  modelId: string,
  updates: Record<string, unknown> = {}
) {
  const db = getDbInstance();
  const row = db
    .prepare("SELECT value FROM key_value WHERE namespace = 'customModels' AND key = ?")
    .get(providerId);
  if (!row) return null;

  const value = getKeyValue(row).value;
  if (!value) return null;

  const models = JSON.parse(value);
  const index = models.findIndex((m: JsonRecord) => m.id === modelId);
  if (index === -1) return null;

  const current = models[index];
  const currentCompat = (current as JsonRecord).compatByProtocol as CompatByProtocolMap | undefined;
  let mergedCompat: CompatByProtocolMap | undefined = currentCompat;
  if (
    updates.compatByProtocol !== undefined &&
    typeof updates.compatByProtocol === "object" &&
    updates.compatByProtocol !== null &&
    !Array.isArray(updates.compatByProtocol)
  ) {
    mergedCompat = deepMergeCompatByProtocol(
      currentCompat,
      updates.compatByProtocol as Partial<
        Record<ModelCompatProtocolKey, Partial<ModelCompatPerProtocol>>
      >
    );
    if (!compatByProtocolHasEntries(mergedCompat)) mergedCompat = undefined;
  }

  const next: JsonRecord = {
    ...current,
    ...(updates.modelName !== undefined ? { name: updates.modelName || current.name } : {}),
    ...(updates.apiFormat !== undefined ? { apiFormat: updates.apiFormat } : {}),
    ...(updates.targetFormat !== undefined ? { targetFormat: updates.targetFormat } : {}),
    ...(updates.supportedEndpoints !== undefined
      ? { supportedEndpoints: updates.supportedEndpoints }
      : {}),
    ...(updates.normalizeToolCallId !== undefined
      ? { normalizeToolCallId: Boolean(updates.normalizeToolCallId) }
      : {}),
    ...(updates.isHidden !== undefined ? { isHidden: Boolean(updates.isHidden) } : {}),
  };
  applyTriStateBooleanOverride(next, updates, "preserveOpenAIDeveloperRole");
  // #1904: manual vision-capability override — `null` clears back to the
  // id-based heuristic in getCustomVisionCapabilityFields().
  applyTriStateBooleanOverride(next, updates, "supportsVision");
  if (updates.compatByProtocol !== undefined) {
    if (mergedCompat && compatByProtocolHasEntries(mergedCompat)) {
      next.compatByProtocol = mergedCompat;
    } else {
      delete next.compatByProtocol;
    }
  }

  if (Object.prototype.hasOwnProperty.call(updates, "upstreamHeaders")) {
    const uh = updates.upstreamHeaders;
    if (uh === null || uh === undefined) {
      delete next.upstreamHeaders;
    } else if (typeof uh === "object" && !Array.isArray(uh)) {
      const s = sanitizeUpstreamHeadersMap(uh as Record<string, unknown>);
      if (Object.keys(s).length === 0) delete next.upstreamHeaders;
      else next.upstreamHeaders = s;
    }
  }

  models[index] = next;

  db.prepare("UPDATE key_value SET value = ? WHERE namespace = 'customModels' AND key = ?").run(
    JSON.stringify(models),
    providerId
  );

  backupDbFile("pre-write");
  return next;
}

/** Single custom model row from key_value customModels, or null */
function getCustomModelRow(providerId: string, modelId: string): JsonRecord | null {
  const db = getDbInstance();
  const row = db
    .prepare("SELECT value FROM key_value WHERE namespace = 'customModels' AND key = ?")
    .get(providerId);
  const value = getKeyValue(row).value;
  if (!value) return null;
  try {
    const models = JSON.parse(value) as unknown;
    if (!Array.isArray(models)) return null;
    const isIdMatch = (x: unknown, id: string): boolean => {
      if (!x || typeof x !== "object" || Array.isArray(x)) return false;
      return (x as { id?: string }).id === id;
    };
    // #7364: exact match first; case-insensitive fallback so "glm-4.6V" resolves a
    // custom model saved as "glm-4.6v" (see lookupCustomModelMeta in
    // src/sse/services/model.ts for the sibling lookup this mirrors).
    const m = (models.find((x: unknown) => isIdMatch(x, modelId)) ??
      models.find(
        (x: unknown) =>
          x &&
          typeof x === "object" &&
          !Array.isArray(x) &&
          typeof (x as { id?: string }).id === "string" &&
          ((x as { id: string }).id as string).toLowerCase() === modelId.toLowerCase()
      )) as JsonRecord | undefined;
    return m ?? null;
  } catch {
    return null;
  }
}

/**
 * Whether the given provider/model has "normalize tool call id" (9-char Mistral-style) enabled.
 * Custom model row wins; otherwise {@link getModelCompatOverrides}.
 * When `sourceFormat` is one of `openai` | `openai-responses` | `claude`, per-protocol
 * `compatByProtocol[sourceFormat].normalizeToolCallId` overrides the legacy top-level flag.
 */
export function getModelNormalizeToolCallId(
  providerId: string,
  modelId: string,
  sourceFormat?: string | null
): boolean {
  const m = getCustomModelRow(providerId, modelId);
  const protocol = sourceFormat && isCompatProtocolKey(sourceFormat) ? sourceFormat : null;

  if (m) {
    if (protocol) {
      const pc = (m.compatByProtocol as CompatByProtocolMap | undefined)?.[protocol];
      if (pc && Object.prototype.hasOwnProperty.call(pc, "normalizeToolCallId")) {
        return Boolean(pc.normalizeToolCallId);
      }
    }
    return Boolean(m.normalizeToolCallId);
  }
  const co = readCompatList(providerId).find((e) => e.id === modelId);
  if (protocol && co?.compatByProtocol?.[protocol]) {
    const pc = co.compatByProtocol[protocol]!;
    if (Object.prototype.hasOwnProperty.call(pc, "normalizeToolCallId")) {
      return Boolean(pc.normalizeToolCallId);
    }
  }
  return Boolean(co?.normalizeToolCallId);
}

/**
 * Explicit preserve-openai-developer preference for this provider/model.
 * `undefined` = unset → routing keeps legacy default (preserve developer for OpenAI format).
 * `false` = map developer → system (e.g. MiniMax). `true` = keep developer.
 * Per-protocol overrides live under `compatByProtocol[sourceFormat]` when `sourceFormat` matches.
 */
export function getModelPreserveOpenAIDeveloperRole(
  providerId: string,
  modelId: string,
  sourceFormat?: string | null
): boolean | undefined {
  const m = getCustomModelRow(providerId, modelId);
  const protocol = sourceFormat && isCompatProtocolKey(sourceFormat) ? sourceFormat : null;

  if (m) {
    if (protocol) {
      const pc = (m.compatByProtocol as CompatByProtocolMap | undefined)?.[protocol];
      if (pc && Object.prototype.hasOwnProperty.call(pc, "preserveOpenAIDeveloperRole")) {
        return Boolean(pc.preserveOpenAIDeveloperRole);
      }
    }
    if (Object.prototype.hasOwnProperty.call(m, "preserveOpenAIDeveloperRole")) {
      return Boolean(m.preserveOpenAIDeveloperRole);
    }
    return undefined;
  }
  const co = readCompatList(providerId).find((e) => e.id === modelId);
  if (protocol && co?.compatByProtocol?.[protocol]) {
    const pc = co.compatByProtocol[protocol]!;
    if (Object.prototype.hasOwnProperty.call(pc, "preserveOpenAIDeveloperRole")) {
      return Boolean(pc.preserveOpenAIDeveloperRole);
    }
  }
  if (co && Object.prototype.hasOwnProperty.call(co, "preserveOpenAIDeveloperRole")) {
    return Boolean(co.preserveOpenAIDeveloperRole);
  }
  return undefined;
}

/**
 * Check if the model is flagged as hidden from the public catalog.
 */
export function getModelIsHidden(providerId: string, modelId: string): boolean {
  const m = getCustomModelRow(providerId, modelId);
  if (m && Object.prototype.hasOwnProperty.call(m, "isHidden")) {
    return Boolean(m.isHidden);
  }
  const co = readCompatList(providerId).find((e) => e.id === modelId);
  return Boolean(co?.isHidden);
}

/**
 * Get a map of provider ID → set of hidden model IDs from all modelCompatOverrides
 * and customModels. Used by auto-combo candidate building to skip user-hidden models.
 * Single bulk DB query — not N+1 per model.
 */
export function getHiddenModelsByProvider(): Map<string, Set<string>> {
  const db = getDbInstance();
  const visibilityByProvider = new Map<string, Map<string, boolean>>();
  const rows = db
    .prepare(
      "SELECT namespace, key, value FROM key_value WHERE namespace IN ('modelCompatOverrides', 'customModels')"
    )
    .all() as Array<{ namespace: string; key: string; value: string | null }>;

  for (const namespace of ["modelCompatOverrides", "customModels"]) {
    for (const row of rows) {
      if (row.namespace !== namespace || !row.value) continue;
      try {
        const parsed = JSON.parse(row.value);
        if (!Array.isArray(parsed)) continue;
        for (const entry of parsed) {
          if (!entry || typeof entry !== "object") continue;
          const modelId = (entry as { id?: unknown }).id;
          if (typeof modelId !== "string" || modelId.length === 0) continue;
          if (!Object.prototype.hasOwnProperty.call(entry, "isHidden")) continue;
          let visibility = visibilityByProvider.get(row.key);
          if (!visibility) {
            visibility = new Map<string, boolean>();
            visibilityByProvider.set(row.key, visibility);
          }
          visibility.set(modelId, Boolean((entry as { isHidden?: unknown }).isHidden));
        }
      } catch {
        // Skip malformed entries
      }
    }
  }

  return new Map(
    [...visibilityByProvider].flatMap(([providerId, visibility]) => {
      const hiddenModels = [...visibility].flatMap(([modelId, isHidden]) =>
        isHidden ? [modelId] : []
      );
      return hiddenModels.length > 0 ? [[providerId, new Set(hiddenModels)] as const] : [];
    })
  );
}

/**
 * #3782 — Check if a model was DELETED (trash) rather than merely eye-hidden.
 *
 * Only the DELETE route sets `isDeleted`. The sync re-import filter keys on this
 * (not on `isHidden`) so eye-hidden models survive a re-sync while deleted ones
 * stay dropped.
 *
 * Legacy caveat: rows written by the DELETE route BEFORE this change carry only
 * `isHidden:true` (no `isDeleted`). Treating bare legacy `isHidden:true` as
 * deleted here would resurrect the #3782 bug for eye-hidden models; treating it
 * as "kept" would resurrect previously-deleted models. Resurrecting a deleted
 * model is the less-surprising, recoverable outcome (the operator can re-hide or
 * re-delete it), whereas silently dropping an eye-hidden model is the reported
 * regression — so we deliberately key ONLY on the explicit `isDeleted` flag and
 * accept that a handful of pre-existing deleted rows may reappear once after the
 * upgrade. Going forward both paths write the correct distinct markers.
 */
export function getModelIsDeleted(providerId: string, modelId: string): boolean {
  const co = readCompatList(providerId).find((e) => e.id === modelId);
  return Boolean(co?.isDeleted);
}

/**
 * Persist the hidden flag for a model. Stores the override on the custom-model
 * row when one exists, otherwise on the compat-override list. Setting
 * `hidden = false` is a no-op when the model is already visible.
 */
export function setModelIsHidden(providerId: string, modelId: string, hidden: boolean): void {
  const customRow = getCustomModelRow(providerId, modelId);
  if (customRow) {
    if (hidden) {
      updateCustomModel(providerId, modelId, { isHidden: true });
    } else if (Object.prototype.hasOwnProperty.call(customRow, "isHidden")) {
      updateCustomModel(providerId, modelId, { isHidden: false });
    }
    return;
  }

  const list = readCompatList(providerId);
  const idx = list.findIndex((e) => e.id === modelId);
  if (hidden) {
    const prev = idx >= 0 ? list[idx] : { id: modelId };
    const next: ModelCompatOverride = { ...prev, id: modelId, isHidden: true };
    if (idx >= 0) list[idx] = next;
    else list.push(next);
    writeCompatList(providerId, list);
    return;
  }

  if (idx < 0) return;
  if (Object.keys(list[idx]).length <= 1) {
    // Only `id` left; drop the entry entirely.
    const filtered = list.filter((_, i) => i !== idx);
    writeCompatList(providerId, filtered);
    return;
  }
  delete list[idx].isHidden;
  writeCompatList(providerId, list);
}

function readUpstreamFromJsonRecord(
  row: JsonRecord | null | undefined,
  key: "upstreamHeaders"
): Record<string, string> | undefined {
  if (!row) return undefined;
  const raw = row[key];
  if (!raw || typeof raw !== "object" || Array.isArray(raw)) return undefined;
  const s = sanitizeUpstreamHeadersMap(raw as Record<string, unknown>);
  return Object.keys(s).length > 0 ? s : undefined;
}

/**
 * Extra HTTP headers to send to the upstream provider for this model (after executor auth headers).
 * Order: top-level `upstreamHeaders` on the custom model row (override list merged under custom),
 * then per-protocol `compatByProtocol[sourceFormat].upstreamHeaders` (wins on key conflict).
 * Use for gateways that expect `Authentication`, `X-API-Key`, etc. alongside Bearer.
 *
 * `modelId` should be the **canonical** model id when known. Callers that accept client aliases
 * (e.g. chat proxy) should merge results for both alias and `resolveModelAlias(alias)` so UI
 * config on the resolved id still applies — see `chatCore` merge.
 */
export function getModelUpstreamExtraHeaders(
  providerId: string,
  modelId: string,
  sourceFormat?: string | null
): Record<string, string> {
  const protocol = sourceFormat && isCompatProtocolKey(sourceFormat) ? sourceFormat : null;
  const m = getCustomModelRow(providerId, modelId);

  const base: Record<string, string> = {};
  if (m) {
    const fromModel = readUpstreamFromJsonRecord(m, "upstreamHeaders");
    if (fromModel) Object.assign(base, fromModel);
    if (protocol) {
      const pc = (m.compatByProtocol as CompatByProtocolMap | undefined)?.[protocol];
      const fromProto = pc?.upstreamHeaders;
      if (fromProto && typeof fromProto === "object") {
        Object.assign(base, sanitizeUpstreamHeadersMap(fromProto as Record<string, unknown>));
      }
    }
    return base;
  }

  const co = readCompatList(providerId).find((e) => e.id === modelId);
  if (co?.upstreamHeaders) {
    Object.assign(base, sanitizeUpstreamHeadersMap(co.upstreamHeaders as Record<string, unknown>));
  }
  if (protocol && co?.compatByProtocol?.[protocol]?.upstreamHeaders) {
    Object.assign(
      base,
      sanitizeUpstreamHeadersMap(
        co.compatByProtocol[protocol]!.upstreamHeaders as Record<string, unknown>
      )
    );
  }
  return base;
}