//! 组织树 API
//!
//! 两个独立接口：
//! 1. /api/organization-tree — 返回多级组织->项目树
//! 2. /api/cabinets/filter — 根据组织/项目筛选设备列表

use axum::extract::{State, Query};
use axum::Json;
use serde::Deserialize;
use serde_json::{json, Value};
use std::collections::{BTreeMap, HashMap};

use super::organizations::{CabinetRow, OrganizationRow, ProjectRow, TreeNode};
use crate::error::AppError;
use crate::middleware::auth::{self, CurrentUser};
use crate::commands::AppState;

/// SQL查询专用结构体（只包含数据库字段）
#[derive(Debug, Clone, sqlx::FromRow)]
struct CabinetSqlRow {
    id: i64,
    project_id: Option<i64>,
    abstract_id: Option<String>,
    imei: String,
    iccid: Option<String>,
    name: Option<String>,
    address: Option<String>,
    project_address: Option<String>,
    status: i8,
    board_count: Option<i64>,
    channel_count: Option<i64>,
    idle_count: Option<i64>,
    charging_count: Option<i64>,
    full_count: Option<i64>,
    fault_count: Option<i64>,
}

impl From<CabinetSqlRow> for CabinetRow {
    fn from(row: CabinetSqlRow) -> Self {
        CabinetRow {
            id: row.id,
            project_id: row.project_id,
            abstract_id: row.abstract_id,
            imei: row.imei,
            iccid: row.iccid,
            name: row.name,
            address: row.address,
            project_address: row.project_address,
            status: row.status,
            board_count: row.board_count,
            channel_count: row.channel_count,
            idle_count: row.idle_count,
            charging_count: row.charging_count,
            full_count: row.full_count,
            fault_count: row.fault_count,
            rssi: None,
            pow_fail_dc: None,
            pow_fail_ac: None,
            is_online: None,
            org_disabled: None,
        }
    }
}

// ---------------------------------------------------------------------------
// SQL 常量
//
// 说明：以下 SQL 均由原函数体**原样搬移**，未改动任何 SELECT 字段列表、
// 子查询、JOIN 条件与 WHERE 条件（含 CAST(... AS CHAR) 与 DBX 占位符 `?`）。
// ---------------------------------------------------------------------------

/// 全部组织（组织树用）
const ORGS_ALL_SQL: &str = "SELECT id, name, parent_id, disabled FROM organizations ORDER BY id";

/// 全部项目（经纬度转 CHAR，规避 sqlx 的 DECIMAL 解码问题）
const PROJECTS_ALL_SQL: &str = "SELECT id, organization_id, name, address, CAST(latitude AS CHAR) AS latitude, CAST(longitude AS CHAR) AS longitude FROM projects ORDER BY id";

/// 各项目下的设备数量
const PROJECT_CABINET_COUNTS_SQL: &str =
    "SELECT project_id, COUNT(*) as cnt FROM cabinets GROUP BY project_id";

/// 设备列表基础 SQL：联表查询获取通道状态统计（子查询 idle_count/charging_count/... 原样保留）
const CABINET_FILTER_BASE_SQL: &str = "
        SELECT 
            c.id, c.project_id, c.abstract_id, c.imei, c.iccid, c.name, c.address,
            (SELECT address FROM projects WHERE id = c.project_id) as project_address,
            c.status,
            (SELECT COUNT(*) FROM cabin_boards cb WHERE cb.cabinet_id = c.id) as board_count,
            (SELECT COUNT(*) FROM cabin_boards cb2 
             JOIN compartments comp ON comp.cabin_board_id = cb2.id 
             WHERE cb2.cabinet_id = c.id) as channel_count,
            (SELECT COUNT(*) FROM cabin_boards cb3 
             JOIN compartments comp2 ON comp2.cabin_board_id = cb3.id 
             WHERE cb3.cabinet_id = c.id AND comp2.status = 0) as idle_count,
            (SELECT COUNT(*) FROM cabin_boards cb4 
             JOIN compartments comp3 ON comp3.cabin_board_id = cb4.id 
             WHERE cb4.cabinet_id = c.id AND comp3.status = 1) as charging_count,
            (SELECT COUNT(*) FROM cabin_boards cb5 
             JOIN compartments comp4 ON comp4.cabin_board_id = cb5.id 
             WHERE cb5.cabinet_id = c.id AND comp4.status = 2) as full_count,
            (SELECT COUNT(*) FROM cabin_boards cb6 
             JOIN compartments comp5 ON comp5.cabin_board_id = cb6.id 
             WHERE cb6.cabinet_id = c.id AND comp5.status = 3) as fault_count
        FROM cabinets c
    ";

/// 设备归属校验（非总管理员）：设备必须属于当前用户组织
const DEVICE_ACCESS_SQL: &str = "SELECT EXISTS(SELECT 1 FROM cabinets c \
                 JOIN projects p ON c.project_id = p.id \
                 WHERE c.imei = ? AND p.organization_id = ?)";

// ---------------------------------------------------------------------------
// 组织树
// ---------------------------------------------------------------------------

/// 组织树接口 — 返回多级组织->项目树（含设备数量）
pub async fn organization_tree(
    user: CurrentUser,
    State(state): State<AppState>,
) -> Result<Json<Value>, AppError> {
    auth::check_permission(&user, "device:view")?;

    let db = &state.mysql;

    // 获取所有组织
    let orgs: Vec<OrganizationRow> = sqlx::query_as(ORGS_ALL_SQL).fetch_all(db).await?;

    // 获取所有项目
    let projects: Vec<ProjectRow> = sqlx::query_as(PROJECTS_ALL_SQL).fetch_all(db).await?;

    // 获取每个项目的设备数量
    let project_count_map = fetch_project_counts(db).await?;

    // 递归构建树
    let tree = build_tree(&orgs, &projects, &project_count_map, None);

    Ok(Json(json!({ "code": 0, "data": tree, "message": "ok" })))
}

/// 查询「项目ID -> 设备数量」映射
async fn fetch_project_counts(db: &sqlx::MySqlPool) -> Result<HashMap<i64, i64>, AppError> {
    let project_counts: Vec<(i64, i64)> = sqlx::query_as(PROJECT_CABINET_COUNTS_SQL)
        .fetch_all(db)
        .await?;
    Ok(project_counts.into_iter().collect())
}

/// 递归构建「组织 -> 项目」树节点，项目名称携带设备数量
fn build_tree(
    orgs: &[OrganizationRow],
    projects: &[ProjectRow],
    project_count_map: &HashMap<i64, i64>,
    parent_id: Option<i64>,
) -> Vec<TreeNode> {
    orgs.iter()
        .filter(|o| o.parent_id == parent_id)
        .map(|org| {
            // 递归获取子组织
            let children = build_tree(orgs, projects, project_count_map, Some(org.id));

            // 获取该组织下的项目
            let org_projects: Vec<TreeNode> = projects
                .iter()
                .filter(|p| p.organization_id == Some(org.id))
                .map(|p| {
                    let count = project_count_map.get(&p.id).copied().unwrap_or(0);
                    TreeNode {
                        id: p.id,
                        name: format!("{} ({})", p.name, count),
                        children: None,
                        abstract_id: None,
                        imei: None,
                        status: None,
                        disabled: None,
                        address: p.address.clone(),
                        latitude: p.latitude.clone(),
                        longitude: p.longitude.clone(),
                    }
                })
                .collect();

            // 合并子组织和项目
            let mut all_children = children;
            all_children.extend(org_projects);

            // 计算本组织下的总设备数量
            let total_count: i64 = all_children
                .iter()
                .map(|c| {
                    // 从项目名称中提取数量
                    if let Some(start) = c.name.rfind('(') {
                        if let Some(end) = c.name.rfind(')') {
                            c.name[start + 1..end].parse().unwrap_or(0)
                        } else {
                            0
                        }
                    } else {
                        0
                    }
                })
                .sum();

            TreeNode {
                id: org.id,
                name: format!("{} ({})", org.name, total_count),
                children: if all_children.is_empty() {
                    None
                } else {
                    Some(all_children)
                },
                abstract_id: None,
                imei: None,
                status: None,
                disabled: org.disabled,
                address: None,
                latitude: None,
                longitude: None,
            }
        })
        .collect()
}

// ---------------------------------------------------------------------------
// 设备列表筛选
// ---------------------------------------------------------------------------

/// 设备列表筛选参数
#[derive(Deserialize)]
pub struct CabinetFilterParams {
    pub organization_id: Option<i64>,
    pub project_id: Option<i64>,
    pub page: Option<i64>,
    pub page_size: Option<i64>,
    pub bound: Option<String>,
}

/// 设备列表接口 — 根据组织/项目筛选
pub async fn filter_cabinets(
    user: CurrentUser,
    State(state): State<AppState>,
    Query(params): Query<CabinetFilterParams>,
) -> Result<Json<Value>, AppError> {
    auth::check_permission(&user, "device:view")?;

    let db = &state.mysql;

    let page = params.page.unwrap_or(1).max(1);
    let page_size = params.page_size.unwrap_or(12).clamp(1, 100);
    let offset = (page - 1) * page_size;

    // 组织/项目过滤 + 已绑定/未绑定过滤
    let (where_clause, binds) = build_filter_where(&params, &user);

    // 总数量
    let total = fetch_filter_total(db, &where_clause, &binds).await;

    if total == 0 || offset >= total {
        return Ok(Json(json!({ "code": 0, "data": { "total": 0, "data": [] }, "message": "ok" })));
    }

    // 分页数据
    let sql_rows = fetch_filter_page(db, &where_clause, &binds, page_size, offset).await?;

    // 转换为CabinetRow
    let mut rows: Vec<CabinetRow> = sql_rows.into_iter().map(CabinetRow::from).collect();

    // 从Redis获取实时状态（Pipeline批量HGET，1次网络往返）
    attach_realtime_status(&state, &mut rows).await?;

    // 查询柜子所属组织是否禁用（甲方禁用客户组织 → 前端显示徽标）
    attach_org_disabled(db, &mut rows).await;

    Ok(Json(json!({ "code": 0, "data": { "total": total, "data": rows }, "message": "ok" })))
}

/// 构造设备列表的 WHERE/JOIN 片段及其绑定参数（分支顺序与语义与原实现一致）
fn build_filter_where(
    params: &CabinetFilterParams,
    user: &CurrentUser,
) -> (String, Vec<String>) {
    let (where_clause, binds): (String, Vec<String>) = if let Some(proj_id) = params.project_id {
        ("WHERE c.project_id = ?".into(), vec![proj_id.to_string()])
    } else if let Some(org_id) = params.organization_id {
        ("JOIN projects p ON c.project_id = p.id 
         WHERE p.organization_id IN (
            SELECT id FROM organizations WHERE id = ? OR parent_id = ?
         )".into(), vec![org_id.to_string(), org_id.to_string()])
    } else if user.role_level >= 2 {
        (String::new(), vec![])
    } else if let Some(org_id) = user.organization_id {
        ("JOIN projects p ON c.project_id = p.id 
         WHERE p.organization_id = ?".into(), vec![org_id.to_string()])
    } else {
        ("WHERE 1=0".into(), vec![])
    };

    // 已绑定/未绑定过滤（绑定 = 分配到项目）
    let where_clause = match params.bound.as_deref() {
        Some("1") => append_bound_filter(where_clause, "WHERE c.project_id IS NOT NULL", " AND c.project_id IS NOT NULL"),
        Some("0") => append_bound_filter(where_clause, "WHERE c.project_id IS NULL", " AND c.project_id IS NULL"),
        _ => where_clause,
    };

    (where_clause, binds)
}

/// 追加「已绑定/未绑定」条件：片段为空时用 `where_new`，否则用 `and_tail` 续接
fn append_bound_filter(where_clause: String, where_new: &str, and_tail: &str) -> String {
    if where_clause.is_empty() {
        where_new.to_string()
    } else {
        let mut clause = where_clause;
        clause.push_str(and_tail);
        clause
    }
}

/// 统计符合条件的设备总数（查询失败按 0 处理，与原实现一致）
async fn fetch_filter_total(db: &sqlx::MySqlPool, where_clause: &str, binds: &[String]) -> i64 {
    let count_sql = format!("SELECT COUNT(*) FROM cabinets c {}", where_clause);
    let mut count_query = sqlx::query_scalar::<_, i64>(&count_sql);
    for b in binds {
        count_query = count_query.bind(b);
    }
    count_query.fetch_one(db).await.unwrap_or(0)
}

/// 查询当前页设备行（分页参数由 WHERE 之后的 LIMIT ? OFFSET ? 绑定）
async fn fetch_filter_page(
    db: &sqlx::MySqlPool,
    where_clause: &str,
    binds: &[String],
    page_size: i64,
    offset: i64,
) -> Result<Vec<CabinetSqlRow>, AppError> {
    let data_sql = format!("{} {} ORDER BY c.id LIMIT ? OFFSET ?", CABINET_FILTER_BASE_SQL, where_clause);
    let mut data_query = sqlx::query_as::<_, CabinetSqlRow>(&data_sql);
    for b in binds {
        data_query = data_query.bind(b);
    }
    let rows: Vec<CabinetSqlRow> = data_query
        .bind(page_size)
        .bind(offset)
        .fetch_all(db)
        .await?;
    Ok(rows)
}

/// 从 Redis 批量补齐实时状态（Pipeline HGET，1 次网络往返）
async fn attach_realtime_status(state: &AppState, rows: &mut [CabinetRow]) -> Result<(), AppError> {
    // 使用多路复用连接（MultiplexedConnection），替代已废弃的 aio::Connection
    let mut conn = open_redis_conn(state).await?;

    // 用Pipeline一次发所有HGET命令（每个设备1次HGET取4个字段）
    let mut pipe = redis::pipe();
    for row in rows.iter() {
        let key = format!("device:{}", row.imei);
        pipe.cmd("HGET").arg(&key).arg("online");
        pipe.cmd("HGET").arg(&key).arg("rssi");
        pipe.cmd("HGET").arg(&key).arg("pow_fail_dc");
        pipe.cmd("HGET").arg(&key).arg("pow_fail_ac");
    }

    // 一次发送，获取所有结果
    let results: Vec<Option<String>> = pipe.query_async(&mut conn).await.unwrap_or_default();

    // 每4个一组解析
    for (i, row) in rows.iter_mut().enumerate() {
        let base = i * 4;
        row.is_online = results.get(base).and_then(|v| v.as_ref()).map(|v| v == "1");
        row.rssi = results
            .get(base + 1)
            .and_then(|v| v.as_ref())
            .and_then(|v| v.parse::<i32>().ok());
        row.pow_fail_dc = results
            .get(base + 2)
            .and_then(|v| v.as_ref())
            .map(|v| v == "1");
        row.pow_fail_ac = results
            .get(base + 3)
            .and_then(|v| v.as_ref())
            .map(|v| v == "1");
    }

    Ok(())
}

/// 标记柜子所属组织是否被禁用（甲方禁用客户组织 → 前端显示徽标）
async fn attach_org_disabled(db: &sqlx::MySqlPool, rows: &mut [CabinetRow]) {
    let project_ids: Vec<i64> = rows.iter().filter_map(|r| r.project_id).collect();
    if project_ids.is_empty() {
        return;
    }

    let placeholders: Vec<String> = project_ids.iter().map(|_| "?".to_string()).collect();
    let sql = format!(
        r#"SELECT p.id, o.disabled FROM projects p
                   LEFT JOIN organizations o ON p.organization_id = o.id
                   WHERE p.id IN ({})"#,
        placeholders.join(",")
    );
    let mut q = sqlx::query_as::<_, (i64, i8)>(&sql);
    for pid in &project_ids {
        q = q.bind(pid);
    }
    if let Ok(results) = q.fetch_all(db).await {
        let disabled_map: HashMap<i64, bool> =
            results.into_iter().map(|(pid, d)| (pid, d == 1)).collect();
        for row in rows.iter_mut() {
            row.org_disabled = row.project_id.and_then(|pid| disabled_map.get(&pid)).copied();
        }
    }
}

// ---------------------------------------------------------------------------
// 设备实时状态
// ---------------------------------------------------------------------------

/// 设备实时状态参数
#[derive(Deserialize)]
pub struct DeviceStatusParams {
    pub imei: String,
}

/// 打开 Redis 多路复用连接（失败按原错误信息返回内部错误）
async fn open_redis_conn(state: &AppState) -> Result<redis::aio::MultiplexedConnection, AppError> {
    let client = redis::Client::open(state.redis_url.as_str()).map_err(|e| {
        AppError::Internal(format!("Redis客户端创建失败: {}", e))
    })?;
    // 使用多路复用连接（MultiplexedConnection），替代已废弃的 aio::Connection
    client.get_multiplexed_async_connection().await.map_err(|e| {
        AppError::Internal(format!("Redis连接失败: {}", e))
    })
}

/// 设备实时状态接口 — 返回板级+通道级状态
pub async fn device_realtime_status(
    user: CurrentUser,
    State(state): State<AppState>,
    Query(params): Query<DeviceStatusParams>,
) -> Result<Json<Value>, AppError> {
    auth::check_permission(&user, "device:view")?;

    // 校验设备归属
    ensure_device_access(&state, &user, &params.imei).await?;

    let mut conn = open_redis_conn(&state).await?;

    let device_status = load_device_status(&mut conn, &params.imei).await;
    let boards = load_boards_status(&mut conn, &params.imei).await;

    Ok(Json(json!({
        "code": 0,
        "data": {
            "device": device_status,
            "boards": boards,
        },
        "message": "ok"
    })))
}

/// 设备归属校验：非总管理员必须能通过「设备 → 项目 → 组织」链路命中本组织
async fn ensure_device_access(
    state: &AppState,
    user: &CurrentUser,
    imei: &str,
) -> Result<(), AppError> {
    if user.role_level < 2 {
        if let Some(org_id) = user.organization_id {
            let has_access: bool = sqlx::query_scalar(DEVICE_ACCESS_SQL)
                .bind(imei)
                .bind(org_id)
                .fetch_one(&state.mysql)
                .await
                .unwrap_or(false);
            if !has_access {
                return Err(AppError::Forbidden("无权访问该设备".into()));
            }
        } else {
            return Err(AppError::Forbidden("无权访问该设备".into()));
        }
    }
    Ok(())
}

/// 读取设备级字段（online / rssi / pow_fail_dc / pow_fail_ac）
async fn load_device_status(
    conn: &mut redis::aio::MultiplexedConnection,
    imei: &str,
) -> Value {
    let device_key = format!("device:{}", imei);

    // 获取设备级字段
    let fields = vec!["online", "rssi", "pow_fail_dc", "pow_fail_ac"];
    let values: Vec<Option<String>> = redis::cmd("HMGET")
        .arg(&device_key)
        .arg(&fields)
        .query_async(&mut *conn)
        .await
        .unwrap_or_default();

    json!({
        "online": values.get(0).and_then(|v| v.as_ref()).map(|v| v == "1").unwrap_or(false),
        "rssi": values.get(1).and_then(|v| v.as_ref()).and_then(|v| v.parse::<i32>().ok()),
        "pow_fail_dc": values.get(2).and_then(|v| v.as_ref()).map(|v| v == "1").unwrap_or(false),
        "pow_fail_ac": values.get(3).and_then(|v| v.as_ref()).map(|v| v == "1").unwrap_or(false),
    })
}

/// 通道级 key `device:{imei}:board:{板号}:ch:{通道号}` 的段数（板号/通道号均十进制不补零）
const CHANNEL_KEY_SEGMENTS: usize = 6;
/// 仓控板号量程：协议 §3.7「仓控板 1–15」
const BOARD_ID_MIN: i64 = 1;
const BOARD_ID_MAX: i64 = 15;
/// 通道号量程：协议 §3.7「通道 1–8」（不是 0–7）
const CHANNEL_ID_MIN: i64 = 1;
const CHANNEL_ID_MAX: i64 = 8;

/// 从通道级 key 解析 `(板号, 通道号)`：段数为 6 / 第 3 段是 `board` / 第 5 段是 `ch` /
/// 板号在 1–15、通道号在 1–8 才算合法，否则 `None`。
///
/// 为什么必须按段解析：`KEYS device:{imei}:board:*:ch:*` 会把内部键
/// `...:ch:{通道号}:bat`（电池台账）与 `...:ch:{通道号}:order`（订单电量累加器）也扫出来，
/// 按段校验能把它们挡掉，**不会生成幽灵板/幽灵通道**。
fn parse_channel_key(key: &str) -> Option<(i64, i64)> {
    let parts: Vec<&str> = key.split(':').collect();
    if parts.len() != CHANNEL_KEY_SEGMENTS
        || parts.get(2) != Some(&"board")
        || parts.get(4) != Some(&"ch")
    {
        return None;
    }
    let board_no: i64 = parts.get(3)?.parse().ok()?;
    let channel_no: i64 = parts.get(5)?.parse().ok()?;
    if !(BOARD_ID_MIN..=BOARD_ID_MAX).contains(&board_no)
        || !(CHANNEL_ID_MIN..=CHANNEL_ID_MAX).contains(&channel_no)
    {
        return None;
    }
    Some((board_no, channel_no))
}

/// 扫描并组装全部仓控板状态（板级 + 通道级）。
///
/// ⚠️ 设备上报链路**只写通道级 key**（`device:{imei}:board:{板号}:ch:{通道号}`，
/// 见 `workers/report_worker.rs::write_channel_state`），**新协议里根本没有板级 hash**
/// （老实现的 `device:{imei}:board:{板号}.status_hex` 已不复存在）。
/// 旧代码按 `KEYS device:{imei}:board:*` 取"板级 key"，实际扫到的全是 `...:ch:{通道号}`
/// 这类 key，把**通道号当成了板号** → 返回一堆幽灵板（每个还都没有 channels），
/// 这也是本接口"永远返回空"的另一半原因。
/// 现在改为扫描通道级 key、**按解析出的板号分组**，再由通道数据组装板级视图。
async fn load_boards_status(
    conn: &mut redis::aio::MultiplexedConnection,
    imei: &str,
) -> Value {
    let ch_pattern = format!("device:{}:board:*:ch:*", imei);
    let ch_keys: Vec<String> = redis::cmd("KEYS")
        .arg(&ch_pattern)
        .query_async(&mut *conn)
        .await
        .unwrap_or_default();

    // 板号 → [(通道号, key)]：BTreeMap 保证板号升序，输出顺序稳定
    let mut grouped: BTreeMap<i64, Vec<(i64, String)>> = BTreeMap::new();
    for key in ch_keys {
        if let Some((board_no, channel_no)) = parse_channel_key(&key) {
            grouped.entry(board_no).or_default().push((channel_no, key));
        }
    }

    let mut boards = json!({});
    for (board_no, mut entries) in grouped {
        entries.sort_by_key(|(channel_no, _)| *channel_no);
        let board = load_board_status(conn, &entries).await;
        boards[board_no.to_string().as_str()] = board;
    }

    boards
}

/// 由**已排序**的通道级 key 组装单块仓控板的响应（板级 + 通道级）。
async fn load_board_status(
    conn: &mut redis::aio::MultiplexedConnection,
    entries: &[(i64, String)],
) -> Value {
    let mut channels = json!({});
    let mut status_hex = String::new();
    for (channel_no, ch_key) in entries {
        let channel = load_channel_status(conn, ch_key).await;
        // 板级 `status_hex` 已废弃（新协议板级没有状态字节）：
        // 用各通道的 `batt_status + pow_status`（各 2 位 hex）按**通道号升序**拼回，
        // 与旧格式 `0001000200...` 同构，语义完全由真实字段解释 —— **字段名保持不变**。
        if let Some(hex) = channel.get("hex").and_then(|v| v.as_str()) {
            status_hex.push_str(hex);
        }
        channels[channel_no.to_string().as_str()] = channel;
    }

    json!({
        "status_hex": status_hex,
        "channels": channels,
    })
}

/// 电池状态位（协议 §3.8 `batt_status`）：bit0 充满 / bit1 正在充电 /
/// bit4 过欠压 / bit5 过流 / bit6 热失控 / bit7 有电池
const BATT_FULL_MASK: u8 = 0x01;
const BATT_CHARGING_MASK: u8 = 0x02;
const BATT_FAULT_MASK: u8 = 0x10 | 0x20 | 0x40;
/// 电源状态位（协议 §3.8 `pow_status`）：bit0 电源故障
const POW_FAULT_MASK: u8 = 0x01;

/// 2 位（兼容 1 位）hex → u8；字段缺失 / 长度超 2 / 非 hex → `None`
/// （与 `web/src/utils/deviceStatus.ts::parseHexByte` 口径一致）
fn parse_hex_byte(raw: Option<&str>) -> Option<u8> {
    let text = raw?.trim();
    if text.is_empty() || text.len() > 2 {
        return None;
    }
    u8::from_str_radix(text, 16).ok()
}

/// 纯函数：把通道的**真实字段**组装成响应 JSON。
///
/// **响应字段名与旧实现完全一致**（前端在消费），但取值改为由真实字段推导：
/// - `on`     = `batt_status` bit1（0x02 正在充电）
/// - `full`   = `batt_status` bit0（0x01 充满）
/// - `fault`  = `batt_status` bit4/5/6（过欠压 / 过流 / 热失控）**或** `pow_status` bit0（电源故障）
/// - `hex`    = `batt_status` + `pow_status`（即通道 18 字符 hex 的前 4 个字符；缺任一字节则为空串）
/// - `status` = `fault` > `full` > `charging` > `idle`（与旧实现的优先级顺序一致）
/// - `temp`   = 原样透传（单位 **K×100**，由前端换算，见 `web/.../cabinet.tsx`）
/// 另外**新增** `batt_status` / `pow_status` / `soc`（‰）/ `voltage`（mV）/ `current`（mA）
/// 便于管理端展示真实语义（新增字段不影响既有字段名）。
/// 位定义与前端 `web/src/utils/deviceStatus.ts` 完全一致（两端口径必须一致）。
fn derive_channel_view(
    batt_raw: Option<&str>,
    pow_raw: Option<&str>,
    soc: Option<i64>,
    voltage: Option<i64>,
    current: Option<i64>,
    temp: Option<i64>,
) -> Value {
    let batt = parse_hex_byte(batt_raw);
    let pow = parse_hex_byte(pow_raw);

    let full = batt.is_some_and(|b| b & BATT_FULL_MASK != 0);
    let on = batt.is_some_and(|b| b & BATT_CHARGING_MASK != 0);
    let fault = batt.is_some_and(|b| b & BATT_FAULT_MASK != 0)
        || pow.is_some_and(|p| p & POW_FAULT_MASK != 0);

    let status = if fault {
        "fault"
    } else if full {
        "full"
    } else if on {
        "charging"
    } else {
        "idle"
    };

    // 统一输出小写 2 位 hex（与 `report_worker` 的写入格式一致）
    let batt_status = batt.map(|b| format!("{:02x}", b)).unwrap_or_default();
    let pow_status = pow.map(|p| format!("{:02x}", p)).unwrap_or_default();
    let hex = if batt_status.is_empty() || pow_status.is_empty() {
        String::new()
    } else {
        format!("{}{}", batt_status, pow_status)
    };

    json!({
        "status": status,
        "on": on,
        "full": full,
        "fault": fault,
        "hex": hex,
        "temp": temp,
        "batt_status": batt_status,
        "pow_status": pow_status,
        "soc": soc,
        "voltage": voltage,
        "current": current,
    })
}

/// 读取单个通道状态。
///
/// ⚠️ 旧实现读的是 `on` / `full` / `fault` / `hex`，但设备上报链路
/// （`workers/report_worker.rs::write_channel_state`）**只写**：
/// `batt_status` / `pow_status`（各 2 位 hex）/ `soc`（‰）/ `voltage`（mV）/
/// `current`（mA）/ `temp`（K×100）—— 旧字段根本不存在，于是本接口恒返回
/// `status:"idle"` + 三个 `false` + `hex:""`，管理端"设备实时详情"一直是坏的。
/// 现在读**真实存在**的字段，再由它们推导旧字段（字段名保持不变，推导规则见 [`derive_channel_view`]）。
async fn load_channel_status(
    conn: &mut redis::aio::MultiplexedConnection,
    ch_key: &str,
) -> Value {
    let ch_fields = vec!["batt_status", "pow_status", "soc", "voltage", "current", "temp"];
    let ch_values: Vec<Option<String>> = redis::cmd("HMGET")
        .arg(ch_key)
        .arg(&ch_fields)
        .query_async(&mut *conn)
        .await
        .unwrap_or_default();

    let text = |idx: usize| -> Option<&str> {
        ch_values.get(idx).and_then(|v| v.as_ref()).map(|v| v.as_str())
    };
    let number = |idx: usize| -> Option<i64> { text(idx).and_then(|v| v.parse::<i64>().ok()) };

    derive_channel_view(
        text(0),
        text(1),
        number(2),
        number(3),
        number(4),
        number(5),
    )
}

// ---------------------------------------------------------------------------
// 单元测试：通道状态推导（协议 §3.8，口径必须与 web 端 deviceStatus.ts 一致）
//
// 只测纯函数（不连 Redis / DB）：这一层是"设备实时详情"接口正确性的关键，
// 因为它负责把 `batt_status` / `pow_status` 翻译成前端消费的旧字段名。
// ---------------------------------------------------------------------------
#[cfg(test)]
mod tests {
    use super::*;

    /// 交付文档 §5.3 示例 `828255152c01f40143`：有电池 + 正在充电、电源已打开
    #[test]
    fn test_derive_channel_view_charging_channel_sets_on_true() {
        let view = derive_channel_view(Some("82"), Some("82"), Some(850), Some(54200), Some(5000), Some(32300));
        assert_eq!(view["status"], "charging");
        assert_eq!(view["on"], true);
        assert_eq!(view["full"], false);
        assert_eq!(view["fault"], false);
        assert_eq!(view["hex"], "8282");
        assert_eq!(view["batt_status"], "82");
        assert_eq!(view["pow_status"], "82");
        assert_eq!(view["soc"], 850);
        assert_eq!(view["voltage"], 54200);
        assert_eq!(view["current"], 5000);
        assert_eq!(view["temp"], 32300);
    }

    /// 充满（`batt_status` bit0）+ 仍在报充电位 → `status` 取「充满」（优先级 full > charging）
    #[test]
    fn test_derive_channel_view_full_battery_prefers_full_over_charging() {
        let view = derive_channel_view(Some("83"), Some("82"), None, None, None, None);
        assert_eq!(view["full"], true);
        assert_eq!(view["on"], true);
        assert_eq!(view["status"], "full");
    }

    /// `batt_status` 的过欠压 / 过流 / 热失控位（bit4/5/6）任一置位 → 故障
    #[test]
    fn test_derive_channel_view_batt_fault_bits_map_to_fault() {
        for (batt, other) in [("10", "00"), ("20", "00"), ("40", "00"), ("10", "82")] {
            let view = derive_channel_view(Some(batt), Some(other), None, None, None, None);
            assert_eq!(view["fault"], true, "batt={batt} pow={other}");
            assert_eq!(view["status"], "fault", "batt={batt} pow={other}");
        }
        // 故障优先级最高：即使同时"充满 + 正在充电"，仍是 fault
        let view = derive_channel_view(Some("43"), Some("00"), None, None, None, None);
        assert_eq!(view["fault"], true);
        assert_eq!(view["status"], "fault");
    }

    /// `pow_status` bit0 = 电源故障 → 通道判故障（与电池状态相互独立）
    #[test]
    fn test_derive_channel_view_pow_fault_maps_to_fault() {
        let view = derive_channel_view(Some("82"), Some("01"), None, None, None, None);
        assert_eq!(view["fault"], true);
        assert_eq!(view["status"], "fault");
        assert_eq!(view["hex"], "8201");
    }

    /// **空仓**：无电池（batt `00`）+ 电源已打开（pow `82`）→ 语义仍是 idle，
    /// 但电源状态照实返回（两维度独立，协议 §3.8）
    #[test]
    fn test_derive_channel_view_empty_channel_keeps_power_status() {
        let view = derive_channel_view(Some("00"), Some("82"), Some(0), Some(0), Some(0), Some(0));
        assert_eq!(view["status"], "idle");
        assert_eq!(view["on"], false);
        assert_eq!(view["full"], false);
        assert_eq!(view["fault"], false);
        assert_eq!(view["hex"], "0082");
        assert_eq!(view["pow_status"], "82");
    }

    /// 字段整体缺失（老数据 / 通道刚建立）→ 全部落空，**不得 panic、不得拼出半个字节**
    #[test]
    fn test_derive_channel_view_missing_fields_yields_idle_and_empty_hex() {
        let view = derive_channel_view(None, None, None, None, None, None);
        assert_eq!(view["status"], "idle");
        assert_eq!(view["on"], false);
        assert_eq!(view["full"], false);
        assert_eq!(view["fault"], false);
        assert_eq!(view["hex"], "");
        assert_eq!(view["batt_status"], "");
        assert_eq!(view["pow_status"], "");
        assert_eq!(view["soc"], Value::Null);
        assert_eq!(view["temp"], Value::Null);
    }

    /// 只有一个字节（例如电源状态缺失）→ `hex` 必须为空串，而不是只拼一半
    #[test]
    fn test_derive_channel_view_single_byte_yields_empty_hex() {
        let view = derive_channel_view(Some("82"), None, None, None, None, None);
        assert_eq!(view["hex"], "");
        assert_eq!(view["batt_status"], "82");
        assert_eq!(view["status"], "charging");
    }

    /// hex 大小写不敏感 + 兼容 1 位写法，输出统一补零小写（与 web 端 `parseHexByte` 一致）
    #[test]
    fn test_derive_channel_view_normalizes_hex_case_and_padding() {
        let view = derive_channel_view(Some("8A"), Some("A"), None, None, None, None);
        assert_eq!(view["batt_status"], "8a");
        assert_eq!(view["pow_status"], "0a");
        assert_eq!(view["hex"], "8a0a");
    }

    /// hex 解析：长度超 2 / 非 hex / 空白 → `None`
    #[test]
    fn test_parse_hex_byte_rejects_malformed_values() {
        assert_eq!(parse_hex_byte(None), None);
        assert_eq!(parse_hex_byte(Some("")), None);
        assert_eq!(parse_hex_byte(Some("   ")), None);
        assert_eq!(parse_hex_byte(Some("123")), None);
        assert_eq!(parse_hex_byte(Some("zz")), None);
        assert_eq!(parse_hex_byte(Some("82")), Some(0x82));
        assert_eq!(parse_hex_byte(Some(" 82 ")), Some(0x82));
    }

    // ---- parse_channel_key：通道级 key 分组（板号 1–15 / 通道号 1–8）-------

    /// 正常通道 key → (板号, 通道号)
    #[test]
    fn test_parse_channel_key_accepts_real_channel_keys() {
        assert_eq!(
            parse_channel_key("device:864720562557021:board:1:ch:3"),
            Some((1, 3))
        );
        assert_eq!(
            parse_channel_key("device:864720562557021:board:15:ch:8"),
            Some((15, 8))
        );
    }

    /// **内部键必须被挡掉**：`...:ch:{通道号}:bat`（电池台账）/ `...:ch:{通道号}:order`（电量累加器）
    /// 若被当成通道，会生成幽灵板（旧实现就是按 KEYS 末段取"板号"的）
    #[test]
    fn test_parse_channel_key_rejects_internal_keys() {
        assert_eq!(
            parse_channel_key("device:864720562557021:board:1:ch:3:bat"),
            None
        );
        assert_eq!(
            parse_channel_key("device:864720562557021:board:1:ch:3:order"),
            None
        );
        // 旧实现会扫到这种"板级 key"（其实不存在），现在也必须拒绝
        assert_eq!(parse_channel_key("device:864720562557021:board:1"), None);
        assert_eq!(parse_channel_key("device:864720562557021"), None);
        assert_eq!(parse_channel_key(""), None);
    }

    /// 量程与结构校验：板号 0/16、通道号 0/9、非数字、段内关键字写错都拒绝
    #[test]
    fn test_parse_channel_key_rejects_out_of_range_and_malformed() {
        assert_eq!(parse_channel_key("device:864720562557021:board:0:ch:3"), None);
        assert_eq!(parse_channel_key("device:864720562557021:board:16:ch:3"), None);
        assert_eq!(parse_channel_key("device:864720562557021:board:1:ch:0"), None);
        assert_eq!(parse_channel_key("device:864720562557021:board:1:ch:9"), None);
        assert_eq!(parse_channel_key("device:864720562557021:board:a:ch:3"), None);
        assert_eq!(parse_channel_key("device:864720562557021:board:1:xx:3"), None);
        assert_eq!(
            parse_channel_key("device:864720562557021:brd:1:ch:3"),
            None
        );
    }
}