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export type LogLevel = "debug" | "info" | "warn" | "error";
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export interface LogFields {
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  [key: string]: unknown;
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}
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export interface Logger {
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  debug: (event: string, fields?: LogFields) => void;
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  info: (event: string, fields?: LogFields) => void;
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  warn: (event: string, fields?: LogFields) => void;
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  error: (event: string, fields?: LogFields) => void;
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  child: (fields: LogFields) => Logger;
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}
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const write = (level: LogLevel, component: string, baseFields: LogFields, event: string, fields: LogFields) => {
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  console.log(
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    JSON.stringify({
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      ts: new Date().toISOString(),
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      level,
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      event,
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      component,
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      ...baseFields,
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      ...fields,
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    }),
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  );
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};
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export const createLogger = (component: string, baseFields: LogFields = {}): Logger => ({
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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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});