import { validateMetricValue } from './health-observation-validate.mjs';
import { assertSymptomRecord, HEALTH_SYMPTOM_LABELS, normalizeSymptomCode } from './health-symptoms.mjs';

const METRIC_SET_LABELS = Object.freeze({
  blood_pressure: '血压',
  heart_rate: '心率',
  weight: '体重',
  spo2: '血氧',
  temperature: '体温',
  sleep: '睡眠',
  symptom: '症状',
});

const METRIC_VALUE_PATTERNS = Object.freeze({
  heart_rate: /(?:心率|脉搏)?\s*(\d{2,3})\b/,
  weight: /(?:体重)?\s*(\d{2,3}(?:\.\d)?)\s*(?:kg|公斤|斤)?/i,
  spo2: /(?:血氧|SpO2|spo2)?\s*(\d{2,3})\s*%?/i,
  temperature: /(?:体温)?\s*(3\d(?:\.\d)?)\s*(?:度|℃|°C)?/,
  sleep: /(?:睡了|睡眠)?\s*(\d+(?:\.\d)?)\s*(?:小时|h|H)/,
});

const METRIC_TYPE_BY_SET = Object.freeze({
  heart_rate: 'hr',
  weight: 'weight',
  spo2: 'spo2',
  temperature: 'temperature',
  sleep: 'sleep_minutes',
});

export function metricSetLabel(metricSet) {
  return METRIC_SET_LABELS[metricSet] ?? metricSet;
}

export function metricValuePrompt(metricSet) {
  switch (metricSet) {
    case 'blood_pressure':
      return '请发送血压数值，如 137/82。';
    case 'heart_rate':
      return '请发送心率（次/分），如 72 或「心率 72」。';
    case 'weight':
      return '请发送体重（kg），如 65.5 或「体重 65.5」。';
    case 'spo2':
      return '请发送血氧（%），如 98。';
    case 'temperature':
      return '请发送体温（℃），如 36.5。';
    case 'sleep':
      return '请发送睡眠时长，如「睡了7小时」。';
    case 'symptom':
      return '请描述症状与严重度，如「头晕 2」（1轻 2中 3重）。';
    default:
      return '请发送数值，或回复「取消」。';
  }
}

export function parseSymptomInput(text) {
  const raw = String(text ?? '').trim();
  if (!raw) return { ok: false, error: 'empty' };

  const severityMatch = raw.match(/(\d)\s*$/);
  const severity = severityMatch ? Number(severityMatch[1]) : 2;
  const namePart = severityMatch ? raw.slice(0, severityMatch.index).trim() : raw;

  for (const [code, label] of Object.entries(HEALTH_SYMPTOM_LABELS)) {
    if (code === 'none' || code === 'other') continue;
    if (namePart.includes(label) || raw.includes(label)) {
      return assertSymptomRecord({ code, severity });
    }
  }

  const normalized = normalizeSymptomCode(namePart);
  if (normalized && normalized !== 'none') {
    return assertSymptomRecord({ code: normalized, severity });
  }

  if (/头晕/.test(raw)) return assertSymptomRecord({ code: 'dizziness', severity });
  if (/头痛/.test(raw)) return assertSymptomRecord({ code: 'headache', severity });
  if (/胸闷/.test(raw)) return assertSymptomRecord({ code: 'chest_tightness', severity });
  if (/心慌|心悸/.test(raw)) return assertSymptomRecord({ code: 'palpitation', severity });
  if (/乏力/.test(raw)) return assertSymptomRecord({ code: 'fatigue', severity });
  if (/气短/.test(raw)) return assertSymptomRecord({ code: 'shortness_of_breath', severity });

  return { ok: false, error: 'unknown_symptom' };
}

export function parseMetricInput(metricSet, text) {
  const raw = String(text ?? '').trim();
  if (!raw) return { ok: false, error: 'empty' };

  if (metricSet === 'symptom') {
    const symptom = parseSymptomInput(raw);
    if (!symptom.ok) return symptom;
    return {
      ok: true,
      metricSet: 'symptom',
      symptomCode: symptom.code,
      severity: symptom.severity,
      label: HEALTH_SYMPTOM_LABELS[symptom.code] ?? symptom.code,
    };
  }

  if (metricSet === 'sleep') {
    const match = raw.match(METRIC_VALUE_PATTERNS.sleep) ?? raw.match(/^(\d+(?:\.\d)?)$/);
    const hours = match ? Number(match[1]) : NaN;
    if (!Number.isFinite(hours)) return { ok: false, error: 'not_numeric' };
    const minutes = Math.round(hours * 60);
    const checked = validateMetricValue('sleep_minutes', minutes);
    if (!checked.ok) return checked;
    return {
      ok: true,
      metricSet: 'sleep',
      valueNum: checked.value,
      unit: checked.unit,
      label: `${hours} 小时`,
    };
  }

  const pattern = METRIC_VALUE_PATTERNS[metricSet];
  const metricType = METRIC_TYPE_BY_SET[metricSet];
  if (!pattern || !metricType) return { ok: false, error: 'unknown_metric_set' };

  const match = raw.match(pattern) ?? raw.match(/^(\d+(?:\.\d)?)$/);
  const value = match ? Number(match[1]) : NaN;
  if (!Number.isFinite(value)) return { ok: false, error: 'not_numeric' };

  const checked = validateMetricValue(metricType, value);
  if (!checked.ok) return checked;

  return {
    ok: true,
    metricSet,
    valueNum: checked.value,
    unit: checked.unit,
    label: `${checked.value}${checked.unit ? ` ${checked.unit}` : ''}`,
  };
}

export function formatGenericConfirmCard({ metricSet, label, context = 'other' }) {
  const contextLabel = context === 'morning' ? '晨间' : context === 'evening' ? '晚间' : '其他';
  const name = metricSetLabel(metricSet);
  return [
    `已识别 → ${name} ${label}`,
    metricSet === 'blood_pressure' ? `情境：${contextLabel}` : '',
    '回复「1」确认保存 | 「2」修改 | 「0」放弃',
  ]
    .filter(Boolean)
    .join('\n');
}

export function formatCommittedReply(pendingValues) {
  if (!pendingValues) return '已记录。回复「0」退出。';
  if (pendingValues.metricSet === 'blood_pressure') {
    return `已记录。收缩压 ${pendingValues.systolic} / 舒张压 ${pendingValues.diastolic}。这不是医疗诊断。回复「1」继续录入，或「0」退出。`;
  }
  if (pendingValues.metricSet === 'symptom') {
    const label = HEALTH_SYMPTOM_LABELS[pendingValues.symptomCode] ?? pendingValues.symptomCode;
    return `已记录症状：${label}（严重度 ${pendingValues.severity}）。这不是医疗诊断。回复「1」继续录入，或「0」退出。`;
  }
  const name = metricSetLabel(pendingValues.metricSet);
  const value = pendingValues.displayLabel ?? pendingValues.valueNum;
  return `已记录${name}：${value}。这不是医疗诊断。回复「1」继续录入，或「0」退出。`;
}

export function buildPendingValuesFromParsed(parsed, { context = 'other', observedAt = Date.now() } = {}) {
  if (parsed.metricSet === 'blood_pressure') {
    return {
      metricSet: 'blood_pressure',
      systolic: parsed.systolic,
      diastolic: parsed.diastolic,
      context,
      observedAt,
    };
  }
  if (parsed.metricSet === 'symptom') {
    return {
      metricSet: 'symptom',
      symptomCode: parsed.symptomCode,
      severity: parsed.severity,
      context: 'other',
      observedAt,
      displayLabel: parsed.label,
    };
  }
  return {
    metricSet: parsed.metricSet,
    valueNum: parsed.valueNum,
    context: parsed.metricSet === 'blood_pressure' ? context : 'any',
    observedAt,
    displayLabel: parsed.label,
  };
}