"use server";

import crypto from "node:crypto";
import { and, eq, sql } from "drizzle-orm";
import { revalidatePath } from "next/cache";
import { z } from "zod";
import { db } from "@/db";
import { activationCodes, sessions, taskInstances, taskTemplates, users } from "@/db/schema";
import { SUBJECT_VALUES } from "@/db/schema";
import { todayStr } from "@/lib/dates";
import { getSessionUser } from "@/lib/auth";

function hashCode(code: string) {
  return crypto.createHash("sha256").update(code).digest("hex");
}

export type CreateCodeState = {
  code?: string;
  childName?: string;
  error?: string;
} | null;

// 家长为指定孩子生成一次性激活码(15 分钟有效)
export async function createActivationCode(
  _prev: CreateCodeState,
  formData: FormData,
): Promise<CreateCodeState> {
  const parent = await getSessionUser();
  if (!parent || parent.role !== "parent") return { error: "请先以家长身份登录" };

  const childId = Number(formData.get("childId"));
  const [child] = await db
    .select()
    .from(users)
    .where(eq(users.id, childId))
    .limit(1);
  if (!child || child.role !== "child" || child.familyId !== parent.familyId) {
    return { error: "孩子不存在" };
  }

  const code = String(crypto.randomInt(0, 1_000_000)).padStart(6, "0");
  await db.insert(activationCodes).values({
    childUserId: child.id,
    codeHash: hashCode(code),
    createdBy: parent.id,
    expiresAt: new Date(Date.now() + 15 * 60_000),
  });

  return { code, childName: child.displayName };
}

// 家长补卡 / 撤销补卡:仅限过去的日期,补卡记录永久带标记
export async function makeupTask(instanceId: number, done: boolean) {
  const parent = await getSessionUser();
  if (!parent || parent.role !== "parent") throw new Error("请先以家长身份登录");

  const [row] = await db
    .select({ date: taskInstances.date, familyId: users.familyId })
    .from(taskInstances)
    .innerJoin(users, eq(users.id, taskInstances.childUserId))
    .where(eq(taskInstances.id, instanceId))
    .limit(1);

  if (!row || row.familyId !== parent.familyId) throw new Error("任务不存在");
  if (row.date >= todayStr()) throw new Error("只能对过去的日期补卡");

  await db
    .update(taskInstances)
    .set({ status: done ? "done" : "pending", isMakeup: done, doneAt: done ? new Date() : null })
    .where(eq(taskInstances.id, instanceId));

  revalidatePath("/parent");
}

// ===== 周模板管理 =====

const templateSchema = z.object({
  childId: z.coerce.number().int().positive(),
  dow: z.coerce.number().int().min(0).max(6).catch(0),
  subject: z.enum(SUBJECT_VALUES).catch("other"),
  mode: z.enum(["weekly", "date", "range", "week"]).catch("weekly"),
  dateStart: z.string().nullish(),
  dateEnd: z.string().nullish(),
  title: z.string().trim().min(1, "任务内容不能为空").max(100, "最多 100 字"),
  requiresPhoto: z.boolean(),
});

async function requireOwnerOfChild(childId: number) {
  const parent = await getSessionUser();
  if (!parent || parent.role !== "parent") throw new Error("请先以家长身份登录");
  const [child] = await db
    .select({ id: users.id })
    .from(users)
    .where(and(eq(users.id, childId), eq(users.familyId, parent.familyId), eq(users.role, "child")))
    .limit(1);
  if (!child) throw new Error("孩子不存在");
  return parent;
}

// 添加模板任务(次日及以后生效,不改动已有历史)
export async function addTemplate(formData: FormData) {
  const parsed = templateSchema.safeParse({
    childId: formData.get("childId"),
    dow: formData.get("dow"),
    subject: formData.get("subject"),
    mode: formData.get("mode"),
    dateStart: formData.get("dateStart") || null,
    dateEnd: formData.get("dateEnd") || null,
    title: formData.get("title"),
    requiresPhoto: formData.get("requiresPhoto") === "on",
  });
  if (!parsed.success) throw new Error(parsed.error.issues[0].message);
  await requireOwnerOfChild(parsed.data.childId);

  const [maxRow] = await db
    .select({ maxSort: sql<number>`COALESCE(MAX(${taskTemplates.sortOrder}), -1)` })
    .from(taskTemplates)
    .where(eq(taskTemplates.childUserId, parsed.data.childId));

  await db.insert(taskTemplates).values({
    childUserId: parsed.data.childId,
    dow: parsed.data.dow,
    subject: parsed.data.subject,
    mode: parsed.data.mode,
    dateStart: parsed.data.dateStart || null,
    dateEnd: parsed.data.dateEnd || null,
    title: parsed.data.title,
    requiresPhoto: parsed.data.requiresPhoto,
    sortOrder: maxRow.maxSort + 1,
  });
  revalidatePath("/parent");
}

// 删除模板任务(同样不影响已生成的历史任务)
export async function deleteTemplate(templateId: number) {
  const parent = await getSessionUser();
  if (!parent || parent.role !== "parent") throw new Error("请先以家长身份登录");
  const [row] = await db
    .select({ id: taskTemplates.id })
    .from(taskTemplates)
    .innerJoin(users, eq(users.id, taskTemplates.childUserId))
    .where(and(eq(taskTemplates.id, templateId), eq(users.familyId, parent.familyId)))
    .limit(1);
  if (!row) throw new Error("任务不存在");
  await db.delete(taskTemplates).where(eq(taskTemplates.id, templateId));
  revalidatePath("/parent");
}

// ===== 设备管理 =====

// 注销某台设备的会话(孩子那台 iPad 下次打开需要重新激活)
export async function revokeSession(sessionId: number) {
  const parent = await getSessionUser();
  if (!parent || parent.role !== "parent") throw new Error("请先以家长身份登录");
  const [row] = await db
    .select({ id: sessions.id })
    .from(sessions)
    .innerJoin(users, eq(users.id, sessions.userId))
    .where(and(eq(sessions.id, sessionId), eq(users.familyId, parent.familyId)))
    .limit(1);
  if (!row) throw new Error("会话不存在");
  await db.delete(sessions).where(eq(sessions.id, sessionId));
  revalidatePath("/parent");
}