import type { DatabaseClient } from "./database";
import { shanghaiDateFromTimestamp } from "./collection-service";
import {
  sendWecomAppMessage,
  sendWecomRobotMessage,
  sendWecomTemplateCard,
  type WecomConfig,
} from "./wecom-client";
import { sendTaskChatMessage } from "./task-group-service";
import { getRuntimeEnv } from "./runtime-env";
import { releaseUnfinishedDistribution } from "./distribution-release-service";

type FetchLike = typeof fetch;

export type WecomNotifySummary = {
  dueSoonAttempted: number;
  dueSoonSent: number;
  dueSoonFailed: number;
  dueSoonSkipped: number;
  digestSent: boolean;
};

type DueSoonRow = {
  distribution_id: string;
  partner_id: string;
  partner_name: string;
  wecom_external_user_id: string | null;
  task_id: string;
  task_name: string;
  due_at: string;
  content_title: string;
};

export function computeDueCutoff(today: string, dueDays: number) {
  const match = /^(\d{4})-(\d{2})-(\d{2})$/.exec(today);
  if (!match) return today;
  const [, y, m, d] = match;
  const date = new Date(
    Date.UTC(Number(y), Number(m) - 1, Number(d)) + dueDays * 24 * 60 * 60 * 1_000,
  );
  return date.toISOString().slice(0, 10);
}

export async function runDueSoonWecomNotifications(
  db: DatabaseClient,
  config: WecomConfig,
  fetchImpl: FetchLike = fetch,
  now: number = Date.now(),
): Promise<WecomNotifySummary> {
  const today = shanghaiDateFromTimestamp(now);
  const cutoff = computeDueCutoff(today, config.dueDays);
  const portalUrl = bindingValue(getRuntimeEnv().KOC_PORTAL_URL);

  const result = await db
    .prepare(
      `SELECT
        d.id AS distribution_id,
        d.partner_id,
        p.name AS partner_name,
        p.wecom_external_user_id,
        t.id AS task_id,
        t.name AS task_name,
        t.due_at,
        c.title AS content_title
       FROM distributions d
       JOIN tasks t ON t.id = d.task_id
       JOIN partners p ON p.id = d.partner_id
       JOIN contents c ON c.id = d.content_id
       WHERE (
             (t.task_type = 'screenshot_collect' AND d.result_submitted_at IS NULL)
             OR (t.task_type != 'screenshot_collect'
                 AND (d.publish_url IS NULL OR d.publish_url = ''))
           )
         AND t.due_at IS NOT NULL AND t.due_at != ''
         AND t.due_at <= ?
       ORDER BY t.due_at ASC, p.name ASC`,
    )
    .bind(cutoff)
    .all<DueSoonRow>();

  const grouped = new Map<
    string,
    {
      partnerName: string;
      externalUserId: string | null;
      rows: DueSoonRow[];
    }
  >();
  for (const row of result.results) {
    const entry = grouped.get(row.partner_id) ?? {
      partnerName: row.partner_name,
      externalUserId: row.wecom_external_user_id,
      rows: [],
    };
    entry.rows.push(row);
    if (!entry.externalUserId && row.wecom_external_user_id) {
      entry.externalUserId = row.wecom_external_user_id;
    }
    grouped.set(row.partner_id, entry);
  }

  let dueSoonAttempted = 0;
  let dueSoonSent = 0;
  let dueSoonFailed = 0;
  let dueSoonSkipped = 0;
  const digestTasks: string[] = [];

  for (const [, entry] of grouped) {
    dueSoonAttempted += 1;
    const external = entry.externalUserId
      ? [entry.externalUserId]
      : [];
    const lines = entry.rows.slice(0, 5).map((row) => {
      return `· 《${truncate(row.task_name, 24)}》— ${truncate(row.content_title, 24)}（截止 ${row.due_at}）`;
    });
    const overflow =
      entry.rows.length > 5 ? `\n…还有 ${entry.rows.length - 5} 条` : "";
    const link = portalUrl ? `\n领取链接：${portalUrl}` : "";
    const content =
      `${entry.partnerName}，你有 ${entry.rows.length} 条内容待发布：\n${lines.join("\n")}${overflow}${link}`;
    const appResult = await sendWecomAppMessage(
      external,
      content,
      config,
      fetchImpl,
    ).catch((error: unknown) => {
      console.warn(
        "[KOC LOOP] wecom app message failed",
        { partner: entry.partnerName, error: safeError(error) },
      );
      return null;
    });
    if (appResult === null) {
      dueSoonFailed += 1;
    } else if (appResult.skipped) {
      dueSoonSkipped += 1;
    } else {
      dueSoonSent += 1;
    }
    const earliestDue = entry.rows[0]?.due_at ?? "";
    digestTasks.push(
      `· ${entry.partnerName}（${entry.rows.length} 条，最近截止 ${earliestDue}）`,
    );
  }

  const byTask = new Map<
    string,
    { taskName: string; dueAt: string; rows: DueSoonRow[] }
  >();
  for (const row of result.results) {
    const entry = byTask.get(row.task_id) ?? {
      taskName: row.task_name,
      dueAt: row.due_at,
      rows: [],
    };
    entry.rows.push(row);
    byTask.set(row.task_id, entry);
  }
  for (const [taskId, entry] of byTask) {
    const partners = [...new Set(entry.rows.map((row) => row.partner_name))];
    const overflow = partners.length > 5 ? ` 等 ${partners.length} 位` : "";
    await sendTaskChatMessage(
      db,
      taskId,
      `【催办】《${truncate(entry.taskName, 24)}》有 ${entry.rows.length} 条内容待发布（截止 ${entry.dueAt}）：\n${partners.slice(0, 5).join("、")}${overflow}`,
      config,
      fetchImpl,
    );
  }

  let digestSent = false;
  if (config.robotWebhook && digestTasks.length > 0) {
    const digest =
      `今日待发布催办（${today}，截止 ≤ ${cutoff}）：\n${digestTasks.join("\n")}`;
    try {
      await sendWecomRobotMessage(digest, config, fetchImpl);
      digestSent = true;
    } catch (error) {
      console.warn(
        "[KOC LOOP] wecom robot digest failed",
        { error: safeError(error) },
      );
    }
  }

  return {
    dueSoonAttempted,
    dueSoonSent,
    dueSoonFailed,
    dueSoonSkipped,
    digestSent,
  };
}

function bindingValue(value: unknown) {
  return String(value ?? "").trim();
}

export function resolveAutoReleaseDays(value: string | undefined) {
  const parsed = Number(String(value ?? "").trim());
  if (!Number.isFinite(parsed) || parsed < 1) return 0;
  return Math.min(90, Math.floor(parsed));
}

type OverdueRow = {
  id: string;
  task_id: string;
  task_name: string;
  due_at: string;
  project_id: string;
  partner_id: string;
  partner_name: string;
};

export type OverdueEscalationSummary = {
  overdueTasks: number;
  overdueDistributions: number;
  robotSent: boolean;
  cardSent: number;
  cardFailed: number;
};

async function queryOverdueUnpublished(
  db: DatabaseClient,
  cutoff: string,
): Promise<OverdueRow[]> {
  const result = await db
    .prepare(
      `SELECT d.id, t.id AS task_id, t.name AS task_name, t.due_at,
              t.project_id, p.id AS partner_id, p.name AS partner_name
       FROM distributions d
       JOIN tasks t ON t.id = d.task_id
       JOIN partners p ON p.id = d.partner_id
       WHERE (
             (t.task_type = 'screenshot_collect' AND d.result_submitted_at IS NULL)
             OR (t.task_type != 'screenshot_collect'
                 AND (d.publish_url IS NULL OR d.publish_url = ''))
           )
         AND t.due_at IS NOT NULL AND t.due_at != ''
         AND t.due_at < ?
       ORDER BY t.due_at ASC, t.name ASC`,
    )
    .bind(cutoff)
    .all<OverdueRow>();
  return result.results;
}

export async function runOverdueEscalation(
  db: DatabaseClient,
  config: WecomConfig,
  fetchImpl: FetchLike = fetch,
  now: number = Date.now(),
): Promise<OverdueEscalationSummary> {
  const today = shanghaiDateFromTimestamp(now);
  const rows = await queryOverdueUnpublished(db, today);

  const byTask = new Map<
    string,
    { taskName: string; dueAt: string; projectId: string; count: number; partners: Set<string> }
  >();
  for (const row of rows) {
    const entry = byTask.get(row.task_id) ?? {
      taskName: row.task_name,
      dueAt: row.due_at,
      projectId: bindingValue(row.project_id),
      count: 0,
      partners: new Set<string>(),
    };
    entry.count += 1;
    entry.partners.add(row.partner_name || row.partner_id);
    byTask.set(row.task_id, entry);
  }

  const summary: OverdueEscalationSummary = {
    overdueTasks: byTask.size,
    overdueDistributions: rows.length,
    robotSent: false,
    cardSent: 0,
    cardFailed: 0,
  };

  if (rows.length === 0) return summary;

  if (config.robotWebhook) {
    const lines = [...byTask.values()].map((entry) => {
      const partners = [...entry.partners].slice(0, 5).join("、");
      const overflow = entry.partners.size > 5 ? ` 等 ${entry.partners.size} 位` : "";
      return `· ${truncate(entry.taskName, 24)}（截止 ${entry.dueAt}）：${entry.count} 条超期未发布 — ${partners}${overflow}`;
    });
    try {
      await sendWecomRobotMessage(
        `【超期未发布升级】${today}\n${lines.join("\n")}\n请运营跟进催办或释放。`,
        config,
        fetchImpl,
      );
      summary.robotSent = true;
    } catch (error) {
      console.warn("[KOC LOOP] overdue escalation robot failed", {
        error: safeError(error),
      });
    }
  }

  const env = getRuntimeEnv();
  const cardUrl = bindingValue(env.APP_ORIGIN) || bindingValue(env.KOC_PORTAL_URL);
  for (const [taskId, entry] of byTask) {
    await sendTaskChatMessage(
      db,
      taskId,
      `【超期催办】《${truncate(entry.taskName, 24)}》（截止 ${entry.dueAt}）有 ${entry.count} 条内容超期未发布，请跟进催办或释放。`,
      config,
      fetchImpl,
    );
    if (!entry.projectId) continue;
    try {
      const project = await db
        .prepare("SELECT main_group_member_ids FROM projects WHERE id = ?")
        .bind(entry.projectId)
        .first<{ main_group_member_ids: string }>();
      const members = safeParseIdList(project?.main_group_member_ids);
      if (members.length === 0) continue;
      const sent = await sendWecomTemplateCard(
        config,
        {
          touser: members,
          taskId: `task:${taskId}:due`,
          title: `超期催办：${truncate(entry.taskName, 20)}`,
          description: `${entry.count} 条内容超期未发布（截止 ${entry.dueAt}），请跟进催办或释放`,
          url: cardUrl,
          buttons: [
            { key: "view_task", name: "查看任务", url: cardUrl },
            { key: "mark_handled", name: "已处理" },
          ],
        },
        fetchImpl,
      );
      if (!sent.skipped) {
        summary.cardSent += sent.sent;
        summary.cardFailed += sent.failed;
      }
    } catch (error) {
      summary.cardFailed += 1;
      console.warn("[KOC LOOP] overdue escalation card failed", {
        taskId,
        error: safeError(error),
      });
    }
  }

  return summary;
}

export type AutoReleaseSummary = {
  enabled: boolean;
  days: number;
  cutoff: string;
  released: number;
  blocked: number;
  failed: number;
  robotSent: boolean;
};

export async function runOverdueAutoRelease(
  db: DatabaseClient,
  config: WecomConfig,
  fetchImpl: FetchLike = fetch,
  now: number = Date.now(),
): Promise<AutoReleaseSummary> {
  const days = resolveAutoReleaseDays(getRuntimeEnv().WECOM_AUTO_RELEASE_DAYS);
  const summary: AutoReleaseSummary = {
    enabled: days > 0,
    days,
    cutoff: "",
    released: 0,
    blocked: 0,
    failed: 0,
    robotSent: false,
  };
  if (days <= 0) return summary;

  const today = shanghaiDateFromTimestamp(now);
  summary.cutoff = computeDueCutoff(today, -days);
  const rows = await queryOverdueUnpublished(db, summary.cutoff);

  for (const row of rows) {
    try {
      await releaseUnfinishedDistribution(db, row.id);
      summary.released += 1;
    } catch (error) {
      const status = (error as { status?: number }).status;
      if (status === 409) {
        summary.blocked += 1;
      } else {
        summary.failed += 1;
        console.warn("[KOC LOOP] auto release failed", {
          distributionId: row.id,
          error: safeError(error),
        });
      }
    }
  }

  if (summary.released > 0 && config.robotWebhook) {
    try {
      await sendWecomRobotMessage(
        `【超期自动释放】截止 ${summary.cutoff} 前仍未发布的内容已释放 ${summary.released} 条回库存（跳过 ${summary.blocked} 条已提交、失败 ${summary.failed} 条），可重新领取。`,
        config,
        fetchImpl,
      );
      summary.robotSent = true;
    } catch (error) {
      console.warn("[KOC LOOP] auto release robot failed", {
        error: safeError(error),
      });
    }
  }

  return summary;
}

function safeParseIdList(value: string | null | undefined) {
  try {
    const parsed = JSON.parse(String(value ?? "[]"));
    if (!Array.isArray(parsed)) return [];
    return parsed.map((item) => String(item)).filter(Boolean);
  } catch {
    return [];
  }
}

function truncate(value: string, max: number) {
  return value.length > max ? `${value.slice(0, max)}…` : value;
}

function safeError(error: unknown) {
  return error instanceof Error ? error.message : String(error);
}