/** 时间范围 */
export type TimeRange = '7d' | '30d' | '3m'

/** 单条测量记录 */
export interface RecordItem {
    id: string
    /** 格式 YYYY.MM.DD HH:mm */
    time: string
    weight: number
    bmi: number
    /** 体脂率(%) */
    bodyFat: number
}

/** 统计指标 */
export interface StatsData {
    maxWeight: number
    minWeight: number
    avgWeight: number
    /** 体重变化(kg，正=增重，负=减轻） */
    weightDiff: number
}

/** 全量 mock 记录（最近 3 个月数据，按时间倒序） */
const ALL_RECORDS: RecordItem[] = [
    { id: 'r-001', time: '2026.05.12 08:12', weight: 68.2, bmi: 22.0, bodyFat: 18.5 },
    { id: 'r-002', time: '2026.05.11 21:30', weight: 68.5, bmi: 22.1, bodyFat: 18.7 },
    { id: 'r-003', time: '2026.05.10 08:05', weight: 68.8, bmi: 22.3, bodyFat: 18.9 },
    { id: 'r-004', time: '2026.05.09 07:58', weight: 69.0, bmi: 22.4, bodyFat: 19.0 },
    { id: 'r-005', time: '2026.05.08 22:10', weight: 69.3, bmi: 22.5, bodyFat: 19.2 },
    { id: 'r-006', time: '2026.05.07 08:20', weight: 69.5, bmi: 22.6, bodyFat: 19.3 },
    { id: 'r-007', time: '2026.05.06 08:00', weight: 70.0, bmi: 22.7, bodyFat: 19.5 },
    { id: 'r-008', time: '2026.04.30 08:10', weight: 70.3, bmi: 22.8, bodyFat: 19.7 },
    { id: 'r-009', time: '2026.04.20 07:45', weight: 71.0, bmi: 23.0, bodyFat: 20.0 },
    { id: 'r-010', time: '2026.04.10 08:30', weight: 71.8, bmi: 23.2, bodyFat: 20.3 },
    { id: 'r-011', time: '2026.03.28 08:15', weight: 72.5, bmi: 23.5, bodyFat: 20.7 },
    { id: 'r-012', time: '2026.03.15 09:00', weight: 73.2, bmi: 23.7, bodyFat: 21.0 },
    { id: 'r-013', time: '2026.03.01 08:05', weight: 73.8, bmi: 23.9, bodyFat: 21.3 },
]

/** 各时间范围截取数量 */
const RANGE_COUNTS: Record<TimeRange, number> = {
    '7d': 7,
    '30d': 10,
    '3m': 13,
}

/**
 * 按时间范围获取 mock 记录列表
 */
export function getMockRecords(range: TimeRange): RecordItem[] {
    return ALL_RECORDS.slice(0, RANGE_COUNTS[range])
}

/**
 * 根据记录列表计算统计指标
 */
export function calcStats(records: RecordItem[]): StatsData {
    if (!records.length) {
        return { maxWeight: 0, minWeight: 0, avgWeight: 0, weightDiff: 0 }
    }
    const weights = records.map(r => r.weight)
    const maxWeight = Math.max(...weights)
    const minWeight = Math.min(...weights)
    const avgWeight = parseFloat((weights.reduce((a, b) => a + b, 0) / weights.length).toFixed(1))
    // 最新 - 最旧
    const weightDiff = parseFloat((weights[0] - weights[weights.length - 1]).toFixed(1))
    return { maxWeight, minWeight, avgWeight, weightDiff }
}