"""Serialised ESPHome CLI jobs. YAML/secrets stay local; no shell or arbitrary commands."""
import asyncio
from collections import deque
import glob
import json
import os
from pathlib import Path
import re
import shutil
import signal
import time
import yaml
from core import installation_yaml

# libyaml parses a 300 KB profile roughly ten times faster than the pure-Python loader.
class LenientLoader(yaml.CSafeLoader if getattr(yaml, '__with_libyaml__', False) else yaml.SafeLoader):
    """Reads profile metadata without resolving !secret or !include."""
LenientLoader.add_multi_constructor('!', lambda loader, suffix, node: None)

def profile_meta(text):
    """{'node', 'friendly'} from profile YAML, or None when it has no esphome block."""
    data = yaml.load(text, Loader=LenientLoader)
    block = data.get('esphome') if isinstance(data, dict) else None
    if not isinstance(block, dict):
        return None
    substitutions = data.get('substitutions') if isinstance(data.get('substitutions'), dict) else {}
    def resolve(value):
        if isinstance(value, str) and value.startswith('${') and value.endswith('}'):
            value = substitutions.get(value[2:-1])
        return value if isinstance(value, str) else None
    return {'node': resolve(block.get('name')), 'friendly': resolve(block.get('friendly_name'))}

class Firmware:
    def __init__(self, root, data):
        self.root, self.data = Path(root).resolve(), Path(data)
        self.job = None
        self.task = None
        self.logs = deque(maxlen=300)
        self.process = None
        self._names = {}  # file -> (stat signature, meta or None); parsed only when the file changes

    def profiles(self):
        if not self.root.exists(): return []
        return [{'file': p.name} for p in sorted(self.root.glob('*.yaml'))
                if p.name != 'secrets.yaml' and p.is_file() and not p.is_symlink()]

    def profile_names(self):
        """{file: {'node': esphome name, 'friendly': friendly name}} for every readable profile.

        Parsing is cached per file on inode, mtime and size, so a request only pays for changed
        profiles. The dict is rebuilt from the current directory listing, so deleted files drop out.
        """
        found, cache = {}, {}
        for entry in self.profiles():
            path = self.root / entry['file']
            try:
                st = path.stat()
                key = (st.st_ino, st.st_mtime_ns, st.st_size)
                cached = self._names.get(entry['file'])
                if cached and cached[0] == key:
                    meta = cached[1]
                else:
                    meta = profile_meta(path.read_text())
            except (OSError, yaml.YAMLError, UnicodeError):
                continue
            cache[entry['file']] = (key, meta)
            if meta:
                found[entry['file']] = meta
        self._names = cache
        return found

    def ports(self):
        return sorted(set(glob.glob('/dev/serial/by-id/*') or glob.glob('/dev/ttyUSB*') + glob.glob('/dev/ttyACM*')))

    def profile(self, name):
        if not isinstance(name,str) or not re.fullmatch(r'[a-zA-Z0-9_-]+\.yaml', name):
            raise ValueError('Kies een bestaand YAML-profiel.')
        p = self.root / name
        if p.is_symlink() or p.resolve().parent != self.root or not p.is_file():
            raise ValueError('Profiel bestaat niet in de ESPHome-map.')
        return p

    def wifi_status(self):
        # Return availability only; never send secret values to the browser.
        path = self.root / 'secrets.yaml'
        if not path.exists():
            return {'state': 'new', 'missing': ['wifi_ssid', 'wifi_password']}
        try:
            values = yaml.safe_load(path.read_text())
            if not isinstance(values, dict):
                return {'state': 'invalid'}
            missing = [key for key in ('wifi_ssid', 'wifi_password')
                       if not isinstance(values.get(key), str)]
            if isinstance(values.get('wifi_ssid'), str) and not values['wifi_ssid'].strip():
                missing.append('wifi_ssid')
            return {'state': 'missing' if missing else 'ready', 'missing': missing}
        except (OSError, yaml.YAMLError, UnicodeError):
            return {'state': 'invalid'}

    def status(self):
        return {'available': bool(shutil.which('esphome')), 'profiles': self.profiles(),
                'ports': self.ports(), 'job': self.job, 'logs': list(self.logs), 'wifi': self.wifi_status()}

    def create(self, data):
        content = installation_yaml(data)
        self.root.mkdir(parents=True,exist_ok=True)
        # Existing wifi secrets remain untouched. New owners can supply them once.
        secret_path = self.root / 'secrets.yaml'
        wifi = self.wifi_status()
        if wifi['state'] in ('missing', 'invalid'):
            raise ValueError('Controleer wifi_ssid en wifi_password in ESPHome secrets.yaml. Bestaande secrets blijven behouden.')
        if wifi['state'] == 'new':
            ssid, password = data.get('wifi_ssid'), data.get('wifi_password')
            if not isinstance(ssid,str) or not ssid.strip() or not isinstance(password,str):
                raise ValueError('Vul wifi in voor deze eerste installatie.')
            with secret_path.open('x') as f:
                os.chmod(secret_path,0o600)
                yaml.safe_dump({'wifi_ssid':ssid,'wifi_password':password}, f)
        profile = self.root / (data['name']+'.yaml')
        try:
            with profile.open('x') as f:
                os.chmod(profile,0o600);f.write(content)
        except FileExistsError:
            raise ValueError('Deze naam bestaat al. Gebruik het bestaande profiel voor updates.')
        return {'file':profile.name, 'yaml':content}

    def redact(self, text):
        text = re.sub(r'\x1b\[[0-?]*[ -/]*[@-~]', '', text)
        for value in self._secret_values:
            if len(value) >= 3: text=text.replace(value,'[redacted]')
        return re.sub(r'(?i)((?:password|encryption.key|token|ssid)\s*[:=]\s*).+',r'\1[redacted]',text)[:1500]

    def start(self, data):
        if self.task and not self.task.done(): raise ValueError('Er loopt al een build of installatie.')
        profile = self.profile(data.get('file'))
        action = data.get('action')
        if action not in ('validate','build','install'): raise ValueError('Onbekende firmwareactie.')
        if not shutil.which('esphome'): raise ValueError('ESPHome CLI ontbreekt in deze installatie.')
        target = data.get('target','')
        if action == 'install':
            if target.startswith('/dev/'):
                if target not in self.ports(): raise ValueError('Kies de aangesloten USB-poort uit de lijst.')
            elif not re.fullmatch(r'[a-zA-Z0-9][a-zA-Z0-9.-]{0,252}',target):
                raise ValueError('Vul het IP-adres of de hostnaam van het bedoelde scherm in.')
        self._secret_values=set()
        # Collect scalar literals, including !secret values, without executing YAML tags.
        def collect(node):
            if isinstance(node,yaml.ScalarNode):
                if node.value: self._secret_values.add(node.value)
            elif isinstance(node,yaml.SequenceNode):
                for child in node.value: collect(child)
            elif isinstance(node,yaml.MappingNode):
                for key,value in node.value:
                    if key.value in ('password','key','ssid','token') or profile.name=='secrets.yaml':collect(value)
                    elif isinstance(value,(yaml.MappingNode,yaml.SequenceNode)):collect(value)
        collect(yaml.compose(profile.read_text()))
        secret_file=self.root/'secrets.yaml'
        if secret_file.exists():
            node=yaml.compose(secret_file.read_text())
            if isinstance(node,yaml.MappingNode):
                for _,v in node.value:collect(v)
        self.logs.clear()
        self.job={'file':profile.name,'action':action,'target':target,'state':'running','started':time.time()}
        self.task=asyncio.create_task(self.run(profile,action,target))
        return dict(self.job)

    async def run(self, profile, action, target):
        env={**os.environ, 'PLATFORMIO_CORE_DIR':str(self.data/'platformio'), 'ESPHOME_BUILD_PATH':str(self.data/'build'/profile.stem), 'NO_COLOR':'1'}
        try:
            stages = ['config'] if action=='validate' else ['compile'] + (['upload'] if action=='install' else [])
            for stage in stages:
                cmd=['esphome']+(['--quiet'] if stage=='config' else [])+[stage,str(profile)]
                if stage=='upload': cmd += ['--device',target]
                self.logs.append('ESPHome: '+stage)
                self.process=await asyncio.create_subprocess_exec(*cmd,cwd=self.root,env=env,stdout=asyncio.subprocess.PIPE,stderr=asyncio.subprocess.STDOUT,limit=1024*1024,start_new_session=True)
                async with asyncio.timeout(7200):
                    async for line in self.process.stdout:
                        self.logs.append(self.redact(line.decode(errors='replace').rstrip()))
                    code=await self.process.wait()
                if code: raise RuntimeError('ESPHome '+stage+' mislukt; bekijk het log.')
            self.job['state']='success'; self.logs.append('Geslaagd: '+action)
        except asyncio.CancelledError:
            self.job['state']='interrupted'
            raise
        except Exception as error:
            self.job['state']='failed';self.logs.append(self.redact(str(error)))
        finally:
            if self.process and self.process.returncode is None:
                os.killpg(self.process.pid,signal.SIGTERM)
                try: await asyncio.wait_for(self.process.wait(),10)
                except TimeoutError: os.killpg(self.process.pid,signal.SIGKILL);await self.process.wait()
            self.process=None
            self.job['finished']=time.time()