#!/usr/bin/env python3
"""Set up a browser-interactive-testing session.

Creates the output directory, inits the showboat report, starts a browser,
and prints the DIR path. Automatically detects whether rodney can launch
its own Chromium or falls back to a system-installed browser.
"""

import datetime
import os
import shutil
import socket
import subprocess
import sys
import time

REMOTE_DEBUG_PORT = 9222


def find_system_browser():
    """Return the path to a system Chrome/Chromium binary, or None."""
    for name in ["chromium", "chromium-browser", "google-chrome", "google-chrome-stable"]:
        path = shutil.which(name)
        if path:
            return path
    return None


def port_listening(port):
    """Check if something is already listening on the given port."""
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
        s.settimeout(1)
        return s.connect_ex(("localhost", port)) == 0


def try_connect(port):
    """Try to connect rodney to a browser on the given port. Returns True on success."""
    result = subprocess.run(
        ["uvx", "rodney", "connect", "--local", f"localhost:{port}"],
        capture_output=True,
        text=True,
    )
    if result.returncode == 0:
        print(f"Connected to existing browser on port {port}", file=sys.stderr)
        return True
    return False


def launch_system_browser(browser_path):
    """Launch a system browser with remote debugging and wait for it to be ready."""
    subprocess.Popen(
        [
            browser_path,
            "--headless",
            "--disable-gpu",
            f"--remote-debugging-port={REMOTE_DEBUG_PORT}",
            "--no-sandbox",
        ],
        stdout=subprocess.DEVNULL,
        stderr=subprocess.DEVNULL,
    )
    # Wait for the browser to start listening
    for _ in range(20):
        if port_listening(REMOTE_DEBUG_PORT):
            return True
        time.sleep(0.25)
    return False


def start_browser():
    """Start a headless browser and connect rodney to it.

    Strategy order (fastest path first):
    1. Connect to an already-running browser on the debug port.
    2. Launch a system Chrome/Chromium (avoids rodney's Chromium download,
       which fails on some architectures like Linux ARM64).
    3. Let rodney launch its own browser as a last resort.
    """
    # Strategy 1: connect to an already-running browser
    if port_listening(REMOTE_DEBUG_PORT) and try_connect(REMOTE_DEBUG_PORT):
        return

    # Strategy 2: launch a system browser (most reliable on Linux)
    browser = find_system_browser()
    if browser:
        print(f"Launching system browser: {browser}", file=sys.stderr)
        if launch_system_browser(browser):
            if try_connect(REMOTE_DEBUG_PORT):
                return
            print("WARNING: system browser started but rodney could not connect", file=sys.stderr)
        else:
            print("WARNING: system browser did not start in time", file=sys.stderr)

    # Strategy 3: let rodney try its built-in launcher
    result = subprocess.run(
        ["uvx", "rodney", "start", "--local"],
        capture_output=True,
        text=True,
    )
    if result.returncode == 0:
        print("Browser started via rodney", file=sys.stderr)
        return

    print(
        "ERROR: Could not start a browser. Tried:\n"
        f"  - Connecting to localhost:{REMOTE_DEBUG_PORT} (no browser found)\n"
        f"  - System browser: {browser or 'not found'}\n"
        "  - rodney start (failed)\n"
        "Install chromium or google-chrome and try again.",
        file=sys.stderr,
    )
    sys.exit(1)


def ensure_gitignore_entry(entry):
    """Add entry to .gitignore if the file exists and the entry is missing."""
    gitignore = ".gitignore"
    if not os.path.isfile(gitignore):
        return
    with open(gitignore, "r") as f:
        content = f.read()
    # Check if the entry (with or without trailing slash/newline variations) is already present
    lines = content.splitlines()
    if any(line.strip() == entry or line.strip() == entry.rstrip("/") for line in lines):
        return
    # Append the entry
    with open(gitignore, "a") as f:
        if content and not content.endswith("\n"):
            f.write("\n")
        f.write(f"{entry}\n")
    print(f"Added '{entry}' to .gitignore", file=sys.stderr)


def main():
    if len(sys.argv) < 3:
        print(f"Usage: {sys.argv[0]} <slug> <report-title>", file=sys.stderr)
        sys.exit(1)

    slug = sys.argv[1]
    title = sys.argv[2]

    # Create output directory
    d = f".agent-tests/{datetime.date.today()}-{slug}"
    os.makedirs(f"{d}/screenshots", exist_ok=True)

    # Ensure .rodney/ is in .gitignore (rodney stores session files there)
    ensure_gitignore_entry(".rodney/")

    # Init showboat report
    subprocess.run(["uvx", "showboat", "init", f"{d}/report.md", title], check=True)

    # Start browser
    start_browser()

    # Print the directory path (only real stdout, everything else goes to stderr)
    print(d)


if __name__ == "__main__":
    main()