import { v4 as uuidv4 } from "uuid";
import { appEvents } from "../events";
import type { ProcessData, LogEntry } from "./types";

/**
 * Stream output from a readable stream to events
 */
export async function streamOutput(
  processId: string,
  stream: ReadableStream<Uint8Array>,
  type: "stdout" | "stderr",
  processesMap: Map<string, ProcessData>,
  addLogToBuffer?: (processId: string, logEntry: LogEntry) => void,
): Promise<void> {
  const reader = stream.getReader();
  const decoder = new TextDecoder();

  try {
    while (true) {
      const { done, value } = await reader.read();

      if (done) break;

      const chunk = decoder.decode(value, { stream: true });
      const processData = processesMap.get(processId);

      if (processData && chunk) {
        // Add to log buffer if function provided
        if (addLogToBuffer) {
          const logEntry: LogEntry = {
            id: uuidv4(),
            timestamp: new Date(),
            type,
            content: chunk,
            processId,
          };
          addLogToBuffer(processId, logEntry);
        }

        appEvents.emit("runner:output", {
          processId,
          type,
          chunk,
          command: processData.info.command,
          cwd: processData.info.cwd,
        });
      }
    }
  } catch (error) {
    const processData = processesMap.get(processId);
    if (processData) {
      // Add error to log buffer if function provided
      if (addLogToBuffer) {
        const logEntry: LogEntry = {
          id: uuidv4(),
          timestamp: new Date(),
          type: "error",
          content: String(error),
          processId,
        };
        addLogToBuffer(processId, logEntry);
      }

      appEvents.emit("runner:error", {
        processId,
        error: String(error),
        serverInfo: {
          name: processData.info.name,
          command: processData.info.command,
          cwd: processData.info.cwd,
        },
      });
    }
  } finally {
    reader.releaseLock();
  }
}