/**
 * Admin command handlers — /admin subcommands for bot operators.
 */

import type { Bot, Context } from "grammy";
import { readFileSync } from "node:fs";
import type { TalonConfig } from "../../util/config.js";
import { files, dirs } from "../../util/paths.js";
import { tailFile } from "../../util/tail-file.js";
import { escapeHtml } from "./formatting.js";
import { resetSession, getAllSessions } from "../../storage/sessions.js";
import { clearHistory } from "../../storage/history.js";
import { todayLogDate } from "../../storage/daily-log.js";
import { getChatSettings } from "../../storage/chat-settings.js";
import {
  getAllCronJobs,
  describeSchedule,
  nextRunAt,
} from "../../storage/cron-store.js";
import { getActiveCount } from "../../core/engine/dispatcher.js";
import { getPulseStatus } from "../../core/background/pulse.js";
import { getHealthStatus, getRecentErrors } from "../../util/watchdog.js";
import { formatDuration, formatModelLabel } from "./helpers/index.js";

export async function handleAdminCommand(
  ctx: Context,
  bot: Bot,
  config: TalonConfig,
): Promise<void> {
  const args = ((ctx.match as string) ?? "").trim();
  const [subcommand, ...rest] = args.split(/\s+/);

  switch (subcommand) {
    case "chats": {
      const sessions = getAllSessions();
      if (sessions.length === 0) {
        await ctx.reply("No active sessions.");
        return;
      }
      sessions.sort(
        (a, b) => (b.info.lastActive || 0) - (a.info.lastActive || 0),
      );

      const titles = new Map<string, string>();
      await Promise.all(
        sessions.map(async (s) => {
          try {
            const id = parseInt(s.chatId, 10);
            if (isNaN(id)) return;
            const chat = await bot.api.getChat(id);
            titles.set(
              s.chatId,
              "title" in chat
                ? (chat.title ?? "DM")
                : "first_name" in chat
                  ? (chat.first_name ?? "DM")
                  : "DM",
            );
          } catch {
            /* inaccessible */
          }
        }),
      );

      const lines = sessions.map((s) => {
        const age = s.info.lastActive
          ? `${Math.round((Date.now() - s.info.lastActive) / 60000)}m ago`
          : "?";
        const title = titles.get(s.chatId) ?? s.chatId;
        const model = formatModelLabel(
          getChatSettings(s.chatId).model ?? config.model,
        );
        // `model` is a catalog id (OpenRouter/Kilo ids are free-form), so
        // it gets the same escaping the title already had.
        return `<b>${escapeHtml(title)}</b> <code>${s.chatId}</code>\n  ${s.info.turns} turns | ${age} | ${escapeHtml(model)}`;
      });
      await ctx.reply(
        `<b>Active chats (${sessions.length})</b>\n\n` + lines.join("\n\n"),
        { parse_mode: "HTML" },
      );
      return;
    }

    case "broadcast": {
      const text = rest.join(" ");
      if (!text) {
        await ctx.reply("Usage: /admin broadcast <text>");
        return;
      }
      const sessions = getAllSessions();
      let sent = 0,
        failed = 0;
      for (const s of sessions) {
        const id = parseInt(s.chatId, 10);
        if (isNaN(id)) continue;
        try {
          await bot.api.sendMessage(id, text);
          sent++;
          await new Promise((r) => setTimeout(r, 40));
        } catch {
          failed++;
        }
      }
      await ctx.reply(
        `Broadcast: ${sent} sent, ${failed} failed (${sessions.length} total).`,
      );
      return;
    }

    case "kill": {
      const target = rest[0];
      if (!target) {
        await ctx.reply("Usage: /admin kill <chatId>");
        return;
      }
      resetSession(target);
      clearHistory(target);
      await ctx.reply(`Session ${target} reset.`);
      return;
    }

    case "logs": {
      const logPath = files.log;
      try {
        const lines = tailFile(logPath);
        await ctx.reply(`<pre>${escapeHtml(lines.slice(0, 3800))}</pre>`, {
          parse_mode: "HTML",
        });
      } catch {
        await ctx.reply(`Could not read ${logPath}`);
      }
      return;
    }

    case "stats": {
      const h = getHealthStatus();
      const sessions = getAllSessions();
      const turns = sessions.reduce((s, x) => s + x.info.turns, 0);
      const mem = process.memoryUsage();
      await ctx.reply(
        [
          `<b>\uD83E\uDD85 Talon Stats</b>`,
          "",
          `<b>Uptime:</b> ${formatDuration(h.uptimeMs)}`,
          `<b>Messages:</b> ${h.totalMessagesProcessed}`,
          `<b>Sessions:</b> ${sessions.length}`,
          `<b>Turns:</b> ${turns}`,
          `<b>Last active:</b> ${h.msSinceLastMessage < 60000 ? "now" : formatDuration(h.msSinceLastMessage) + " ago"}`,
          "",
          `<b>Memory:</b> ${(mem.heapUsed / 1024 / 1024).toFixed(1)}MB heap / ${(mem.rss / 1024 / 1024).toFixed(1)}MB rss`,
          `<b>Queue:</b> ${getActiveCount()}`,
          `<b>Errors:</b> ${h.recentErrorCount}`,
        ].join("\n"),
        { parse_mode: "HTML" },
      );
      return;
    }

    case "errors": {
      const errors = getRecentErrors(5);
      if (errors.length === 0) {
        await ctx.reply("No recent errors.");
        return;
      }
      const lines = errors.map(
        (e) =>
          `<code>[${new Date(e.timestamp).toISOString().slice(11, 19)}]</code> ${escapeHtml(e.message.slice(0, 200))}`,
      );
      await ctx.reply(
        `<b>Recent Errors (${errors.length})</b>\n\n` + lines.join("\n\n"),
        { parse_mode: "HTML" },
      );
      return;
    }

    case "cron": {
      const jobs = getAllCronJobs();
      if (jobs.length === 0) {
        await ctx.reply("No cron jobs.");
        return;
      }
      const lines = jobs.map((j) => {
        const nextMs = nextRunAt(j);
        const last = j.lastRunAt
          ? new Date(j.lastRunAt).toISOString().slice(0, 16).replace("T", " ")
          : "never";
        const next = nextMs
          ? new Date(nextMs).toISOString().slice(0, 16).replace("T", " ")
          : "?";
        return `${j.enabled ? "\u2713" : "\u2717"} <b>${escapeHtml(j.name)}</b>\n  <code>${escapeHtml(describeSchedule(j))}</code> | ${j.type} | runs: ${j.runCount} | last: ${last} | next: ${next}`;
      });
      await ctx.reply(
        `<b>Cron Jobs (${jobs.length})</b>\n\n` + lines.join("\n\n"),
        { parse_mode: "HTML" },
      );
      return;
    }

    case "pulse": {
      const chats = getPulseStatus();
      if (chats.length === 0) {
        await ctx.reply("No pulse chats.");
        return;
      }
      const lines = await Promise.all(
        chats.map(async (p) => {
          let title = p.chatId;
          try {
            const id = parseInt(p.chatId, 10);
            if (!isNaN(id)) {
              const chat = await bot.api.getChat(id);
              title = "title" in chat ? (chat.title ?? p.chatId) : p.chatId;
            }
          } catch {
            /* skip */
          }
          return `${p.enabled ? "\u2713" : "\u2717"} ${escapeHtml(title)}`;
        }),
      );
      await ctx.reply(`<b>Pulse (${chats.length})</b>\n\n` + lines.join("\n"), {
        parse_mode: "HTML",
      });
      return;
    }

    case "daily": {
      const today = todayLogDate();
      const logPath = `${dirs.logs}/${today}.md`;
      try {
        const content = readFileSync(logPath, "utf-8");
        const lines = content.trim().split("\n").slice(-30).join("\n");
        await ctx.reply(
          `<b>Daily log (${today})</b>\n\n<pre>${escapeHtml(lines.slice(0, 3800))}</pre>`,
          { parse_mode: "HTML" },
        );
      } catch {
        await ctx.reply(`No daily log for ${today}.`);
      }
      return;
    }

    default:
      await ctx.reply(
        [
          "<b>/admin commands</b>",
          "",
          "  stats    uptime, messages, memory",
          "  errors   last 5 errors",
          "  chats    list all active chats",
          "  daily    today's interaction log",
          "  pulse    pulse status per chat",
          "  cron     list all cron jobs",
          "  broadcast &lt;text&gt;  send to all chats",
          "  kill &lt;chatId&gt;     reset a chat session",
          "  logs     last 20 lines of log",
        ].join("\n"),
        { parse_mode: "HTML" },
      );
  }
}