import subprocess
import json
import sys

class GeminiCliAdapter:
    def __init__(self, binary_path="gemini"):
        self.binary_path = binary_path
        self.last_usage = None
        self.session_id = None

    def send(self, message):
        """
        Sends a message to the Gemini CLI and processes the streaming JSON output.
        """
        # On Windows, using shell=True allows executing .cmd/.bat files and 
        # handles command strings with arguments more gracefully.
        # We pass the message via stdin to avoid command-line length limits.
        command = f'{self.binary_path} run --output-format stream-json'
        if self.session_id:
            command += f' --resume {self.session_id}'

        print(f"[DEBUG] GeminiCliAdapter: Executing command: {command}")
        accumulated_text = ""
        
        process = subprocess.Popen(
            command,
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True,
            shell=True
        )

        try:
            # Send message to stdin and close it
            process.stdin.write(message)
            process.stdin.close()

            # Read stdout line by line
            for line in process.stdout:
                line = line.strip()
                if not line:
                    continue
                print(f"[DEBUG] GeminiCliAdapter stdout: {line}")

                try:
                    data = json.loads(line)
                    msg_type = data.get("type")

                    if msg_type == "message":
                        # Append message text to results
                        accumulated_text += data.get("text", "")

                    elif msg_type == "result":
                        # Capture final usage and session persistence
                        self.last_usage = data.get("usage")
                        self.session_id = data.get("session_id")

                    elif msg_type in ("status", "tool_use"):
                        # Log status/tool_use to stderr for debugging
                        sys.stderr.write(f"GeminiCliAdapter [{msg_type}]: {line}\n")
                        sys.stderr.flush()

                except json.JSONDecodeError:
                    # Skip lines that are not valid JSON
                    continue

            process.wait()
            if process.returncode != 0:
                err = process.stderr.read()
                print(f"[DEBUG] GeminiCliAdapter failed with exit code {process.returncode}. stderr: {err}")
        except Exception as e:
            process.kill()
            print(f"[DEBUG] GeminiCliAdapter exception: {e}")
            raise e

        return accumulated_text