from ..structs import MonitorInfo, Modeline
from ..abstracts import AbstractDisplay

import os
import re
import subprocess
import json

# Matches "1920x1080 @ 60.000 Hz" or "1920x1080@60.000"
MODE_REGEX = re.compile(r'(\d+)x(\d+)@(\d+\.\d+)')

class Display(AbstractDisplay):
    def get_modes(self):
        # wlr-randr --json is the 'civilized' way to do this on Trixie
        result = subprocess.run(["wlr-randr", "--json"], capture_output=True, text=True, check=True)
        data = json.loads(result.stdout)
        
        monitors = []
        for output in data:
            modes = []
            for m in output.get("modes", []):
                modes.append(Modeline(
                    width=int(m["width"]),
                    height=int(m["height"]),
                    refresh_rate=float(m["refresh"])
                ))
            
            monitors.append(MonitorInfo(
                connector=output["name"], # Usually 'HEADLESS-1' in Cage
                primary=output.get("focused", False),
                modes=modes
            ))
        return monitors
    
    def set_mode(self, modeline, requested_connector="HEADLESS-1") -> None:
        # Format: 1920x1080@60Hz
        mode_str = f"{modeline.width}x{modeline.height}@{modeline.refresh_rate}Hz"
        subprocess.run(["wlr-randr", "--output", requested_connector, "--mode", mode_str], check=True)

    def save_current_mode(self, location):
        # Implementation similar to your GNOME one but using wlr-randr
        result = subprocess.run(["wlr-randr", "--json"], capture_output=True, text=True, check=True)
        data = json.loads(result.stdout)[0] # Grab first monitor
        curr = data["current_mode"]
        with open(location, "w") as f:
            f.write(f"{curr['width']}x{curr['height']}@{curr['refresh']}")

    def read_saved_mode(self, location):
        with open(location, "r") as f:
            w, h, r = MODE_REGEX.search(f.read()).groups()
        return Modeline(width=int(w), height=int(h), refresh_rate=float(r))

    @staticmethod
    def detect():
        # Cage doesn't always set XDG_CURRENT_DESKTOP, but it's a wlroots compositor
        return os.environ.get("WLR_BACKENDS") == "headless" or "cage" in os.environ.get("XDG_CURRENT_DESKTOP", "").lower()