function num(v, fallback = NaN) {
  const n = Number.parseFloat(v);
  return Number.isFinite(n) ? n : fallback;
}

function low(v) {
  return (v ?? '').toString().trim().toLowerCase();
}

function parseMaybeJson(v) {
  if (typeof v !== 'string') return v;
  try {
    return JSON.parse(v);
  } catch {
    return v;
  }
}

function extractSnapshot(input) {
  if (typeof input === 'string') return parseMaybeJson(input);
  if (input?.data && typeof input.data === 'string') return parseMaybeJson(input.data);
  if (input?.body && typeof input.body === 'string') return parseMaybeJson(input.body);
  if (input?.data && typeof input.data === 'object') return input.data;
  if (input?.body && typeof input.body === 'object') return input.body;
  return input;
}

function round1(v) {
  return Math.round(v * 10) / 10;
}

function clamp(v, min, max) {
  return Math.min(Math.max(v, min), max);
}

function getParisNowParts() {
  const fmt = new Intl.DateTimeFormat('fr-FR', {
    timeZone: 'Europe/Paris',
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
    hour: '2-digit',
    minute: '2-digit',
    second: '2-digit',
    hour12: false,
  });

  const parts = Object.fromEntries(
    fmt.formatToParts(new Date())
      .filter(p => p.type !== 'literal')
      .map(p => [p.type, p.value])
  );

  const date = `${parts.year}-${parts.month}-${parts.day}`;
  const stamp = `${date} ${parts.hour}:${parts.minute}:${parts.second}`;

  return {
    year: Number(parts.year),
    month: Number(parts.month),
    day: Number(parts.day),
    hour: Number(parts.hour),
    minute: Number(parts.minute),
    second: Number(parts.second),
    date,
    stamp,
  };
}

function parseLocalStampToMs(s) {
  const text = (s ?? '').toString().trim();
  const m = text.match(/^(\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2})$/);
  if (!m) return null;

  const y = Number(m[1]);
  const mo = Number(m[2]);
  const d = Number(m[3]);
  const h = Number(m[4]);
  const mi = Number(m[5]);
  const se = Number(m[6]);

  if (![y, mo, d, h, mi, se].every(Number.isFinite)) return null;

  return new Date(y, mo - 1, d, h, mi, se).getTime();
}

const cfg = {
  mobileNotifyDomain: 'notify',
  mobileNotifyService: 'mobile_app_iphone_16_de_tt'
};

const raw = $input.first().json;
const input = extractSnapshot(raw);
const now = getParisNowParts();
const nowMs = parseLocalStampToMs(now.stamp);

const soc = clamp(num(input.soc_percent, 0), 0, 100);
const gridIsOn = low(input.grid_state || 'off') === 'on';
const pvPowerW = Math.max(0, num(input.pv_power_w, 0));

const houseAcPowerW = Math.max(0, num(input.house_ac_power_w, 0));
const gridPowerW = num(input.grid_power_w, 0);

const evcsAcPowerW = Math.max(0, num(input.evcs_ac_power_w, 0));
const evcsCharging = low(input.evcs_charging || 'off') === 'on';
const evcsStatusRaw = num(input.evcs_status_raw, NaN);

const hysteresisEnabled = low(input.hysteresis_enabled || 'off') === 'on';
const notificationsEnabled = low(input.notifications_enabled || 'off') === 'on';
const latchIsOn = low(input.grid_latch || 'off') === 'on';

const gridSocOn = clamp(num(input.grid_soc_on, 22), 0, 100);
const gridSocOff = clamp(num(input.grid_soc_off, 35), 0, 100);
const gridMinOnMinutes = Math.max(0, num(input.grid_min_on_minutes, 45));
const gridCooldownMinutes = Math.max(0, num(input.grid_cooldown_minutes, 15));
const acLoadsMaxSafeW = Math.max(0, num(input.ac_loads_max_safe_w, 7800));

const lastOnAt = (input.last_on_at ?? '').toString().trim();
const lastOffAt = (input.last_off_at ?? '').toString().trim();
const lastSignature = (input.last_signature ?? '').toString().trim();

const lastOnMs = parseLocalStampToMs(lastOnAt);
const lastOffMs = parseLocalStampToMs(lastOffAt);

const minutesSinceLastOn =
  lastOnMs !== null && nowMs !== null ? Math.max(0, (nowMs - lastOnMs) / 60000) : null;

const minutesSinceLastOff =
  lastOffMs !== null && nowMs !== null ? Math.max(0, (nowMs - lastOffMs) / 60000) : null;

const minOnElapsed =
  minutesSinceLastOn === null ? true : minutesSinceLastOn >= gridMinOnMinutes;

const cooldownElapsed =
  minutesSinceLastOff === null ? true : minutesSinceLastOff >= gridCooldownMinutes;

const socBand =
  soc <= gridSocOn ? 'low' :
  soc < gridSocOff ? 'mid' :
  'high';

const evcsSeemsActive = evcsCharging || evcsAcPowerW > 300;
const acOverSafeLimit = houseAcPowerW >= acLoadsMaxSafeW;

let state = 'observe_only';
let reason = [];
let desiredGrid = gridIsOn ? 'on' : 'off';
let desiredLatch = latchIsOn ? 'on' : 'off';

// ======================================================
// Core hysteresis logic V1.1
// ======================================================
if (!hysteresisEnabled) {
  state = 'hysteresis_disabled';
  desiredGrid = gridIsOn ? 'on' : 'off';
  desiredLatch = latchIsOn ? 'on' : 'off';
  reason.push('Automatisme hystérésis réseau désactivé');

} else if (soc <= gridSocOn) {
  // Seuil bas atteint => prise de main immédiate
  desiredGrid = 'on';
  desiredLatch = 'on';

  if (!cooldownElapsed && !gridIsOn) {
    state = 'turn_on_low_soc_cooldown_bypassed';
    reason.push(`SOC ${round1(soc)}% <= seuil ON ${gridSocOn}% : activation EDF malgré cooldown`);
  } else if (!gridIsOn) {
    state = 'turn_on_low_soc';
    reason.push(`SOC ${round1(soc)}% <= seuil ON ${gridSocOn}% : activation EDF`);
  } else if (!latchIsOn) {
    state = 'adopt_existing_grid_on_low_soc';
    reason.push(`SOC ${round1(soc)}% <= seuil ON ${gridSocOn}% : EDF déjà ON, prise de contrôle par latch`);
  } else {
    state = 'hold_on_low_soc';
    reason.push(`SOC encore bas ${round1(soc)}% : maintien EDF ON`);
  }

} else if (gridIsOn && !latchIsOn) {
  // NOUVEAU CAS V1.1 :
  // Le réseau est déjà ON mais ce workflow n'a pas la main.
  if (soc < gridSocOff) {
    desiredGrid = 'on';
    desiredLatch = 'on';
    state = 'adopt_existing_grid_on';
    reason.push(`EDF déjà ON avec latch OFF et SOC ${round1(soc)}% < seuil OFF ${gridSocOff}% : adoption de l'état ON`);
  } else {
    desiredGrid = 'off';
    desiredLatch = 'off';
    state = 'turn_off_stray_grid_on';
    reason.push(`EDF ON avec latch OFF et SOC ${round1(soc)}% >= seuil OFF ${gridSocOff}% : coupure de reprise de contrôle`);
  }

} else if (latchIsOn) {
  // Tant que le latch est actif, on garde la main
  if (!minOnElapsed) {
    desiredGrid = 'on';
    desiredLatch = 'on';
    state = 'hold_on_min_runtime';
    reason.push(`EDF maintenu ON : durée mini ${gridMinOnMinutes} min non atteinte (${round1(minutesSinceLastOn || 0)} min)`);
  } else if (soc < gridSocOff) {
    desiredGrid = 'on';
    desiredLatch = 'on';
    state = 'hold_on_until_soc_off';
    reason.push(`EDF maintenu ON : SOC ${round1(soc)}% < seuil OFF ${gridSocOff}%`);
  } else {
    desiredGrid = 'off';
    desiredLatch = 'off';
    state = 'turn_off_recovered';
    reason.push(`SOC ${round1(soc)}% >= seuil OFF ${gridSocOff}% : coupure EDF`);
  }

} else {
  desiredGrid = 'off';
  desiredLatch = 'off';
  state = 'observe_only';
  reason.push('Aucune action : hors zone d’hystérésis');
}

// ======================================================
// Compare desired vs current
// ======================================================
const gridAction =
  desiredGrid === (gridIsOn ? 'on' : 'off')
    ? 'none'
    : desiredGrid === 'on'
      ? 'turn_on'
      : 'turn_off';

const latchAction =
  desiredLatch === (latchIsOn ? 'on' : 'off')
    ? 'none'
    : desiredLatch === 'on'
      ? 'turn_on'
      : 'turn_off';

// ======================================================
// Timestamps
// ======================================================
// On pose un nouveau "last_on_at" si :
// - on allume réellement EDF
// - ou on adopte un EDF déjà ON avec latch OFF
const setLastOnAt =
  gridAction === 'turn_on' ||
  state === 'adopt_existing_grid_on' ||
  state === 'adopt_existing_grid_on_low_soc';

// On pose "last_off_at" si on coupe réellement EDF
const setLastOffAt =
  gridAction === 'turn_off';

// ======================================================
// Context / alerts
// ======================================================
reason.push(`Grid actuel ${gridIsOn ? 'ON' : 'OFF'}`);
reason.push(`Latch actuel ${latchIsOn ? 'ON' : 'OFF'}`);
reason.push(`SOC ${round1(soc)}% | seuils ${gridSocOn}%/${gridSocOff}%`);
reason.push(`PV ${Math.round(pvPowerW)}W`);
reason.push(`Charge AC maison ${Math.round(houseAcPowerW)}W`);
reason.push(`Puissance réseau ${Math.round(gridPowerW)}W`);
reason.push(`EVCS ${evcsSeemsActive ? 'actif' : 'inactif'} | ${Math.round(evcsAcPowerW)}W | status_raw=${Number.isFinite(evcsStatusRaw) ? evcsStatusRaw : 'n/a'}`);

if (minutesSinceLastOn !== null) {
  reason.push(`Dernier ON il y a ${round1(minutesSinceLastOn)} min`);
}
if (minutesSinceLastOff !== null) {
  reason.push(`Dernier OFF il y a ${round1(minutesSinceLastOff)} min`);
}

if (acOverSafeLimit) {
  reason.push(`⚠️ Charge AC maison ${Math.round(houseAcPowerW)}W >= limite sûre ${Math.round(acLoadsMaxSafeW)}W`);
}

// ======================================================
// Notifications
// ======================================================
let notifyTitle = 'Victron Grid Hysteresis';
let notifyMessage = '';
let notifyWanted = false;

if (state === 'turn_on_low_soc' || state === 'turn_on_low_soc_cooldown_bypassed') {
  notifyTitle = '⚡ EDF activé sur SOC bas';
  notifyMessage = `SOC ${round1(soc)}% <= ${gridSocOn}%. EDF activé et maintenu jusqu'à au moins ${gridSocOff}% (min ${gridMinOnMinutes} min).`;
  notifyWanted = true;

} else if (state === 'adopt_existing_grid_on_low_soc' || state === 'adopt_existing_grid_on') {
  notifyTitle = '🔁 EDF ON repris par hystérésis';
  notifyMessage = `EDF était déjà ON. Le workflow reprend la main et le maintient jusqu'à ${gridSocOff}% (min ${gridMinOnMinutes} min).`;
  notifyWanted = true;

} else if (state === 'turn_off_recovered') {
  notifyTitle = '✅ EDF coupé après recharge';
  notifyMessage = `SOC ${round1(soc)}% >= ${gridSocOff}%. Retour hors réseau autorisé.`;
  notifyWanted = true;

} else if (state === 'turn_off_stray_grid_on') {
  notifyTitle = '✅ EDF coupé (reprise de contrôle)';
  notifyMessage = `EDF était ON sans latch. SOC ${round1(soc)}% >= ${gridSocOff}%, coupure réseau appliquée.`;
  notifyWanted = true;

} else if (acOverSafeLimit && !gridIsOn) {
  notifyTitle = '🚨 Charge AC élevée hors réseau';
  notifyMessage = `Charge AC maison ${Math.round(houseAcPowerW)}W au-dessus de la limite sûre ${Math.round(acLoadsMaxSafeW)}W alors que EDF est OFF.`;
  notifyWanted = true;

} else if (acOverSafeLimit && gridIsOn) {
  notifyTitle = '⚠️ Charge AC élevée';
  notifyMessage = `Charge AC maison ${Math.round(houseAcPowerW)}W proche/au-dessus de la limite sûre ${Math.round(acLoadsMaxSafeW)}W.`;
  notifyWanted = true;
}

const shortReason = reason.join(' | ').slice(0, 255);

const signature = [
  now.date,
  state,
  `dg=${desiredGrid}`,
  `dl=${desiredLatch}`,
  `sb=${socBand}`,
  `ac=${acOverSafeLimit ? '1' : '0'}`
].join('|');

const signatureChanged = signature !== lastSignature;

const result = {
  timestamp_paris: now.stamp,

  inputs: {
    soc_percent: soc,
    grid_state: gridIsOn ? 'on' : 'off',
    pv_power_w: pvPowerW,
    house_ac_power_w: houseAcPowerW,
    grid_power_w: gridPowerW,
    evcs_ac_power_w: evcsAcPowerW,
    evcs_charging: evcsCharging,
    evcs_status_raw: Number.isFinite(evcsStatusRaw) ? evcsStatusRaw : null,
    hysteresis_enabled: hysteresisEnabled,
    notifications_enabled: notificationsEnabled,
    grid_latch: latchIsOn,
    grid_soc_on: gridSocOn,
    grid_soc_off: gridSocOff,
    grid_min_on_minutes: gridMinOnMinutes,
    grid_cooldown_minutes: gridCooldownMinutes,
    ac_loads_max_safe_w: acLoadsMaxSafeW,
    last_on_at: lastOnAt || null,
    last_off_at: lastOffAt || null,
    last_signature: lastSignature || null
  },

  computed: {
    desired_grid: desiredGrid,
    desired_latch: desiredLatch,
    minutes_since_last_on: minutesSinceLastOn !== null ? round1(minutesSinceLastOn) : null,
    minutes_since_last_off: minutesSinceLastOff !== null ? round1(minutesSinceLastOff) : null,
    min_on_elapsed: minOnElapsed,
    cooldown_elapsed: cooldownElapsed,
    ac_over_safe_limit: acOverSafeLimit,
    evcs_seems_active: evcsSeemsActive
  },

  decision: {
    state,
    grid_action: gridAction,
    latch_action: latchAction,
    set_last_on_at: setLastOnAt,
    set_last_off_at: setLastOffAt,
    should_notify: notificationsEnabled && signatureChanged && notifyWanted,
    signature,
    signature_changed: signatureChanged,
    reason,
    short_reason: shortReason
  },

  ha_service_calls: {
    helper_state: {
      domain: 'input_text',
      service: 'set_value',
      data: {
        entity_id: 'input_text.victron_grid_control_state',
        value: state
      }
    },

    helper_reason: {
      domain: 'input_text',
      service: 'set_value',
      data: {
        entity_id: 'input_text.victron_grid_control_reason',
        value: shortReason || 'Aucune raison'
      }
    },

    helper_signature: {
      domain: 'input_text',
      service: 'set_value',
      data: {
        entity_id: 'input_text.victron_grid_control_last_signature',
        value: signature
      }
    },

    helper_latch: {
      domain: 'input_boolean',
      service: desiredLatch === 'on' ? 'turn_on' : 'turn_off',
      data: {
        entity_id: 'input_boolean.victron_grid_hysteresis_latch'
      }
    },

    helper_last_on_at: {
      domain: 'input_datetime',
      service: 'set_datetime',
      data: {
        entity_id: 'input_datetime.victron_grid_last_on_at',
        datetime: now.stamp
      }
    },

    helper_last_off_at: {
      domain: 'input_datetime',
      service: 'set_datetime',
      data: {
        entity_id: 'input_datetime.victron_grid_last_off_at',
        datetime: now.stamp
      }
    },

    grid: {
      domain: 'switch',
      service: desiredGrid === 'on' ? 'turn_on' : 'turn_off',
      data: {
        entity_id: 'switch.edf_general_ok_switch'
      }
    },

    logbook: {
      domain: 'logbook',
      service: 'log',
      data: {
        name: 'Victron Grid Hysteresis',
        message: `${state} | Grid=${desiredGrid} | Latch=${desiredLatch} | SOC=${round1(soc)}% | AC=${Math.round(houseAcPowerW)}W | ${shortReason}`,
        entity_id: 'switch.edf_general_ok_switch'
      }
    },

    mobile_notification: {
      domain: cfg.mobileNotifyDomain,
      service: cfg.mobileNotifyService,
      data: {
        title: notifyTitle,
        message: notifyMessage,
        data: {
          push: {
            "interruption-level": "time-sensitive",
            sound: { name: "default" }
          },
          ttl: 0,
          priority: "high"
        }
      }
    }
  }
};

return [{ json: result }];