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export type LogLevel = "debug" | "info" | "warn" | "error";
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type Fields = Record<string, unknown>;
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const LEVELS: Record<LogLevel, number> = { debug: 10, info: 20, warn: 30, error: 40 };
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let minLevel: LogLevel = "info";
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function parseLevel(input?: string | null): LogLevel {
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  const v = (input || "").toLowerCase();
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  if (v === "debug" || v === "info" || v === "warn" || v === "error") return v;
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  return "info";
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}
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export function setLevel(input?: string) {
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  minLevel = parseLevel(input);
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}
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export interface Logger {
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  debug: (event: string, fields?: Fields) => void;
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  info: (event: string, fields?: Fields) => void;
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  warn: (event: string, fields?: Fields) => void;
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  error: (event: string, fields?: Fields) => void;
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  child: (fields: Fields) => Logger;
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}
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function write(level: LogLevel, component: string, base: Fields, event: string, fields: Fields) {
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  if (LEVELS[level] < LEVELS[minLevel]) return;
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  const entry = JSON.stringify({ ts: new Date().toISOString(), level, component, event, ...base, ...fields });
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  if (level === "error") return console.error(entry);
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  if (level === "warn") return console.warn(entry);
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  console.log(entry);
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}
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export function createLogger(component: string, baseFields: Fields = {}): Logger {
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  return {
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    debug: (event, fields = {}) => write("debug", component, baseFields, event, fields),
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    info: (event, fields = {}) => write("info", component, baseFields, event, fields),
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    warn: (event, fields = {}) => write("warn", component, baseFields, event, fields),
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    error: (event, fields = {}) => write("error", component, baseFields, event, fields),
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    child: (fields) => createLogger(component, { ...baseFields, ...fields }),
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  };
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}
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export function errorContext(error: unknown) {
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  if (error instanceof Error) {
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    return { errorName: error.name, errorMessage: error.message, errorStack: error.stack };
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  }
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  return { errorMessage: String(error) };
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}