import json
import gc
import time
import uasyncio as asyncio

# Import config value
from config import TANK_CAPACITY_L, VERSION


class WebServer:
    def __init__(self, wlan, sensors, start_time, max_conn):
        self.wlan = wlan
        self.sensors = sensors
        self.start_time = start_time
        self.max_conn = max_conn
        self.current = 0
        self.lock = asyncio.Lock()

    async def handle(self, reader, writer):
        async with self.lock:
            if self.current >= self.max_conn:
                writer.close()
                return
            self.current += 1

        try:
            request = await reader.readline()
            path = request.decode().split(" ")[1]

            # Discard headers
            while await reader.readline() != b"\r\n":
                pass

            # ---------- SENSOR JSON ----------
            if path == "/sensor":
                uptime = int(time.time() - self.start_time)

                days = uptime // 86400
                hours = (uptime % 86400) // 3600
                minutes = (uptime % 3600) // 60
                seconds = uptime % 60

                uptime_text = f"{days}d {hours:02}h {minutes:02}m {seconds:02}s"

                data = {
                    "pressure": self.sensors.pressure,
                    "tank_percent": self.sensors.tank_percentage,
                    "cpu_temp": self.sensors.cpu_temp(),
                    "rssi": self.wlan.status("rssi"),
                    "uptime": uptime_text,
                    "mem": gc.mem_free(),
                    "footer": "Powered by Raspberry Pi Pico W & HX710B (" + VERSION + ")"
                }

                writer.write(
                    b"HTTP/1.1 200 OK\r\n"
                    b"Content-Type: application/json\r\n\r\n" +
                    json.dumps(data).encode()
                )

            # ---------- TARE ----------
            elif path == "/tare":
                self.sensors.set_tank_full()

                writer.write(
                    b"HTTP/1.1 200 OK\r\n"
                    b"Content-Type: application/json\r\n\r\n" +
                    json.dumps({"ok": True}).encode()
                )

            # ---------- JAVASCRIPT (CONFIG INJECTED) ----------
            elif path == "/app.js":
                with open("/html/app.js") as f:
                    js = f.read()

                injected = (
                    "// injected by webserver.py\n"
                    f"const TANK_CAPACITY_L = {TANK_CAPACITY_L};\n\n"
                )

                writer.write(
                    b"HTTP/1.1 200 OK\r\n"
                    b"Content-Type: application/javascript\r\n"
                    b"Cache-Control: no-store\r\n\r\n" +
                    injected.encode() +
                    js.encode()
                )

            # ---------- HTML ----------
            else:
                with open("/html/index.html") as f:
                    html = f.read()

                writer.write(
                    b"HTTP/1.1 200 OK\r\n"
                    b"Content-Type: text/html\r\n\r\n" +
                    html.encode()
                )

            await writer.drain()

        finally:
            writer.close()
            await writer.wait_closed()
            async with self.lock:
                self.current -= 1