/** Facility selection uses entity category+primary key, never monitoring point codes. */
import { facilityStatusTone, entityIdentity } from './entityDetail.js'
import { COORDINATE_REASON_TEXT, NO_MAP_LOCATION_TEXT } from './coordinate.js'
import { filterFacilityPoints, FACILITY_DETAIL_CATEGORIES } from './facilityPoints.js'
export function facilityIdentity(input) {
    const identity = entityIdentity(input, 'facility')
    return { ...identity, valid: identity.valid && identity.kind === 'facility' && FACILITY_DETAIL_CATEGORIES.includes(identity.category) }
}
const coordinatesOf = value => value && Number.isFinite(value.longitude) && Number.isFinite(value.latitude)
    ? [value.longitude, value.latitude] : null

/** Resolve only current identity evidence; pipeline location is the along-line geometric midpoint of its validated polyline — never an endpoint, never invented. */
/**
 * 管线定位点 = 沿真实折线的**长度中点**（维护者 2026-10-30 15:57：不许再取起点/终点）。
 * 每段按大圆近似计长（与 pipeDiameter 同一公式），半程落在哪一段就在段内线性插值；
 * 顶点不足或全长为零（重合点）时回那个真实顶点 —— 仍是几何证据，不是编造。
 */
function polylineMidpoint(positions) {
    const points = (Array.isArray(positions) ? positions : [])
        .filter((point) => Array.isArray(point) && Number.isFinite(point[0]) && Number.isFinite(point[1]))
    if (!points.length) return null
    if (points.length === 1) return points[0]
    const rad = Math.PI / 180
    const segmentLength = (a, b) => {
        const h = Math.sin((b[1] - a[1]) * rad / 2) ** 2
            + Math.cos(a[1] * rad) * Math.cos(b[1] * rad) * Math.sin((b[0] - a[0]) * rad / 2) ** 2
        return 12742017.6 * Math.asin(Math.sqrt(Math.min(1, h)))
    }
    const lengths = []
    let total = 0
    for (let i = 1; i < points.length; i += 1) {
        const length = segmentLength(points[i - 1], points[i])
        lengths.push(length)
        total += length
    }
    if (!(total > 0)) return points[0]
    let walked = 0
    for (let i = 0; i < lengths.length; i += 1) {
        const length = lengths[i]
        if (walked + length >= total / 2) {
            const t = length > 0 ? (total / 2 - walked) / length : 0
            return [
                points[i][0] + (points[i + 1][0] - points[i][0]) * t,
                points[i][1] + (points[i + 1][1] - points[i][1]) * t,
            ]
        }
        walked += length
    }
    return points[points.length - 1]
}

export function resolveFacilityPoint({ identity: input, points, detail, network } = {}) {
    const identity = facilityIdentity(input)
    if (!identity.valid) return null
    const row = (points || []).find(item => item.id === identity.id && item.type === identity.category)
    const current = detail && detail.kind === 'facility' && detail.id === identity.id && detail.category === identity.category ? detail : null
    const raw = current?.raw || {}
    let source = row || {}
    let position = null
    let placement = 'pending'
    let reasonText = ''
    let locationHint = ''
    if (identity.category === 'PIPE_NETWORK') {
        const matches = (network?.pipes || []).filter(pipe => String(pipe.sourceId ?? '') === identity.id || String(pipe.networkId ?? '') === identity.id)
        const byCode = matches.length ? matches : (network?.pipes || []).filter(pipe => raw.code && pipe.code === raw.code)
        const pipe = byCode.length === 1 ? byCode[0] : null
        if (pipe) {
            source = pipe
            position = polylineMidpoint(pipe.positions)
            placement = position ? 'drawn' : 'no-location'
            locationHint = position ? '定位到管段几何中点（沿管线长度取中点，非起止点）' : ''
        } else if (network) {
            const blocked = (network.blocked || []).find(item => raw.code && item.code === raw.code)
            placement = blocked ? 'no-location' : 'pending'
            reasonText = blocked?.reasonText || '当前地图尚未取到该管段的可定位几何'
        }
    } else if (current && Object.prototype.hasOwnProperty.call(raw, 'coordinates')) {
        position = coordinatesOf(current.coordinates)
        placement = position ? 'drawn' : 'no-location'
        reasonText = position ? '' : '设施档案未登记坐标'
        // 工程设施不是旧四类设施点契约；新定位必须有后端明确的可渲染结论。
        if (position && identity.category === 'ENGINEERING_FACILITY' && raw.coordinateValidation?.renderable !== true) {
            position = null
            placement = raw.coordinateValidation?.renderable === false ? 'no-location' : 'pending'
            reasonText = placement === 'pending' ? '设施坐标尚未获得地图可渲染校验' : (COORDINATE_REASON_TEXT[raw.coordinateValidation.reason] || NO_MAP_LOCATION_TEXT)
        }
    } else if (row) {
        position = coordinatesOf(row)
        placement = row.placement
        reasonText = row.reasonText || ''
    }
    const status = raw.status ?? row?.status ?? ''
    return {
        key: 'facility-point|' + identity.category + '|' + identity.id,
        id: identity.id, type: identity.category, detailCategory: identity.category,
        code: String(raw.code || source.code || identity.id),
        name: current?.name || source.name || String(raw.name || identity.id),
        status: String(status), tone: facilityStatusTone(status),
        industry: source.industry || raw.industry || '',
        district: source.district ?? raw.district ?? null,
        placement, longitude: position?.[0] ?? null, latitude: position?.[1] ?? null,
        reasonText, locationHint,
    }
}

/** Selected ledger-only entities get one temporary marker, under the SAME filters; global legend counts stay unchanged. */
export function mergeFacilitySelectionPoints(base, selected, filters = {}) {
    if (!selected || selected.placement !== 'drawn') return base
    if (!filterFacilityPoints([selected], filters.types || [], filters).length) return base
    const list = Array.isArray(base) ? base : []
    const index = list.findIndex(row => row.key === selected.key)
    if (index < 0) return [...list, selected]
    return list.map((row, i) => i === index ? selected : row)
}