import type { SelectedModel } from "@/types";
import type { ProviderModel } from "@/lib/providers/types";

export function toSelectedModel(model: ProviderModel): SelectedModel {
  return {
    provider: model.provider,
    modelId: model.id,
    displayName: model.name,
    capabilities: model.capabilities,
    metadata: model.metadata,
  };
}

function hasValue(value: unknown): boolean {
  return value !== undefined && value !== null && value !== "";
}

function selectedModelIdentifiers(model: SelectedModel | undefined): Set<string> {
  const identifiers = new Set<string>();
  if (!model) return identifiers;

  for (const value of [
    model.modelId,
    model.displayName,
    model.metadata?.aiModelId,
    model.metadata?.aiModelCode,
    model.metadata?.aiModelCodeAlias,
  ]) {
    if (hasValue(value)) {
      identifiers.add(String(value));
    }
  }
  return identifiers;
}

function providerModelMatchesSelectedModel(model: ProviderModel, selected: SelectedModel | undefined): boolean {
  if (!selected || model.provider !== selected.provider) return false;

  const identifiers = selectedModelIdentifiers(selected);
  if (identifiers.size === 0) return false;

  return [
    model.id,
    model.name,
    model.metadata?.aiModelId,
    model.metadata?.aiModelCode,
    model.metadata?.aiModelCodeAlias,
  ].some((value) => hasValue(value) && identifiers.has(String(value)));
}

export function shouldUpdateSelectedModelFromProviderModel(
  current: SelectedModel | undefined,
  model: ProviderModel
): boolean {
  if (!current) return true;
  if (current.provider !== model.provider || current.modelId !== model.id) return true;
  if (model.provider !== "popiserver") return false;

  const currentMetadata = current.metadata ?? {};
  const nextMetadata = model.metadata ?? {};
  return ["billingMethod", "aiModelId", "type", "subType", "aiModelCode", "aiModelCodeAlias"].some(
    (key) => !hasValue(currentMetadata[key]) && hasValue(nextMetadata[key])
  );
}

export function chooseModelFromList(
  models: ProviderModel[],
  preferred?: SelectedModel
): SelectedModel | null {
  const model = models.find((item) => providerModelMatchesSelectedModel(item, preferred))
    ?? models.find((item) => item.metadata?.isDefault === 1)
    ?? models[0];
  return model ? toSelectedModel(model) : null;
}