import type { DownloadTask } from "@umt/contracts";
import { Bot, FolderInput, Pause, Play, ShieldAlert } from "lucide-react";
import { useState } from "react";
import { toast } from "sonner";
import {
  DOWNLOAD_STATUS_LABEL,
  DOWNLOAD_STATUS_TONE,
  PAUSE_REASON_LABEL,
  PLAN_STATUS_LABEL,
  useDownloadAction,
  useDownloaderNames,
  usePlan,
} from "~/api/downloads.ts";
import { useDownloadTrace } from "~/api/tasks.ts";
import { openAgentDrawer } from "~/components/agent/agent-store.ts";
import { DetailSection } from "~/components/console/detail-sheet.tsx";
import { JsonView } from "~/components/console/json-view.tsx";
import { KvList } from "~/components/console/kv-list.tsx";
import { StatusBadge } from "~/components/console/status-badge.tsx";
import { OrganizeWizard } from "~/components/organize-wizard/organize-wizard.tsx";
import { Button } from "~/components/ui/button.tsx";
import { relTime } from "~/components/workbench/release-fields.ts";
import { errorMessage } from "~/lib/api.ts";
import { planReasonText } from "~/lib/labels.ts";
import { formatBytes, formatDateTime } from "~/lib/utils.ts";
import { BusinessTimeline } from "./business-timeline.tsx";

const PLAN_PURPOSE_LABEL: Record<string, string> = { fill: "补缺", upgrade: "升级", replace_source: "换源" };

/** 进度:细线 + 文字;总量未知时不伪造百分比 */
export function ProgressLine({ t }: { t: DownloadTask }) {
  const known = t.sizeBytes !== null;
  return (
    <div className="min-w-24">
      <div className="h-1 overflow-hidden rounded-full bg-foreground/[0.08]">
        <div className="h-full rounded-full bg-foreground/60" style={{ width: `${Math.round(t.progress * 100)}%` }} />
      </div>
      <p className="mt-0.5 text-meta text-muted-foreground tabular-nums">
        {known ? `${(t.progress * 100).toFixed(1)}%` : `已下 ${formatBytes(t.downloadedBytes, 1)}`}
      </p>
    </div>
  );
}

export function DownloadStatusBadges({ t }: { t: DownloadTask }) {
  return (
    <span className="flex flex-wrap gap-1">
      <StatusBadge tone={DOWNLOAD_STATUS_TONE[t.status]}>{DOWNLOAD_STATUS_LABEL[t.status]}</StatusBadge>
      {t.pauseReason === "threshold" ? (
        <StatusBadge tone="warning">阈值暂停</StatusBadge>
      ) : t.pauseReason ? (
        <StatusBadge>{PAUSE_REASON_LABEL[t.pauseReason]}</StatusBadge>
      ) : null}
      {!t.managed ? <StatusBadge>未纳管</StatusBadge> : null}
      {t.origin === "adopted" ? <StatusBadge>接管</StatusBadge> : null}
    </span>
  );
}

/** 暂停/恢复:阈值暂停在水位回落前不可手动恢复(服务端强制) */
export function PauseResume({ t, size = "sm" }: { t: DownloadTask; size?: "sm" | "xs" }) {
  const act = useDownloadAction();
  const canPause = ["queued", "downloading", "stalled"].includes(t.status);
  const canResume = t.status === "paused";
  if (!canPause && !canResume) return null;
  const threshold = t.pauseReason === "threshold";
  return (
    <Button
      variant="outline"
      size={size}
      disabled={act.isPending}
      title={threshold ? "阈值暂停，缓存回落到恢复水位后自动恢复" : undefined}
      onKeyDown={(e) => e.stopPropagation()}
      onClick={(e) => {
        e.stopPropagation();
        act.mutate(
          { id: t.id, action: canResume ? "resume" : "pause" },
          {
            onSuccess: () => toast.success(canResume ? "已恢复" : "已暂停。阈值回落时不会自动恢复"),
            onError: (err) => toast.error(errorMessage(err)),
          },
        );
      }}
    >
      {canResume ? <Play /> : <Pause />}
      {canResume ? "恢复" : "暂停"}
    </Button>
  );
}

/** 下载任务详情:状态、阈值说明、业务时间线、文件、关联计划 */
export function DownloadDetail({ task }: { task: DownloadTask }) {
  const plan = usePlan(task.acquisitionPlanId);
  const names = useDownloaderNames();
  const trace = useDownloadTrace(task, plan.data);
  const [organizing, setOrganizing] = useState(false);
  const canOrganize = ["completed", "importing", "imported"].includes(task.status);

  return (
    <div className="space-y-5">
      <div className="flex flex-wrap items-center gap-2">
        <DownloadStatusBadges t={task} />
        <div className="ml-auto flex flex-wrap gap-2">
          <PauseResume t={task} />
          <Button
            variant="outline"
            size="sm"
            disabled={!canOrganize}
            title={canOrganize ? undefined : "下载完成后才能整理"}
            onClick={() => setOrganizing(true)}
          >
            <FolderInput />
            整理
          </Button>
          <Button
            variant="ghost"
            size="sm"
            onClick={() =>
              openAgentDrawer({
                label: `下载：${task.name}`,
                downloadTaskId: task.id,
                goal: task.status === "stalled" || task.status === "failed" ? "排查这个下载为什么没有进展" : "",
              })
            }
          >
            <Bot />问 Agent
          </Button>
        </div>
      </div>

      {task.pauseReason === "threshold" ? (
        <p className="flex items-start gap-2 rounded-lg border border-warning/40 bg-warning/10 px-3 py-2 text-caption text-warning">
          <ShieldAlert className="mt-0.5 h-3.5 w-3.5 shrink-0" />
          缓存卷达到硬阈值，任务已暂停，水位回落到恢复线后自动恢复。手动恢复和 Agent 都不能绕过阈值。
        </p>
      ) : null}
      {task.noProgressSince ? (
        <p className="rounded-lg border border-warning/40 bg-warning/10 px-3 py-2 text-caption text-warning">
          自 {formatDateTime(task.noProgressSince)} 起无进展，已记入待处理，不会自动换源。
        </p>
      ) : null}

      <DetailSection title="进度">
        <ProgressLine t={task} />
        <KvList
          className="mt-3"
          items={[
            { label: "下载器", value: names.data?.get(task.instanceId) ?? task.instanceId.slice(0, 8) },
            { label: "大小", value: task.sizeBytes === null ? "未知" : formatBytes(task.sizeBytes, 2) },
            { label: "剩余", value: task.remainingBytes === null ? "未知" : formatBytes(task.remainingBytes, 2) },
            { label: "分享率", value: task.ratio === null ? "—" : task.ratio.toFixed(2) },
            { label: "最近进展", value: relTime(task.lastProgressAt) },
            { label: "最近同步", value: relTime(task.lastSyncedAt) },
            { label: "标签", value: task.tags.join(", ") },
            { label: "分类", value: task.category },
            { label: "保存路径", value: task.savePath, mono: true, wide: true },
            { label: "内容路径", value: task.contentPath, mono: true, wide: true },
            { label: "torrent hash", value: task.torrentHash, mono: true, wide: true },
          ]}
        />
      </DetailSection>

      <DetailSection title="业务时间线">
        <BusinessTimeline events={trace.events} loading={trace.loading} />
      </DetailSection>

      {plan.data ? (
        <DetailSection title="下载计划">
          <KvList
            items={[
              { label: "状态", value: PLAN_STATUS_LABEL[plan.data.status] },
              { label: "用途", value: PLAN_PURPOSE_LABEL[plan.data.purpose] ?? plan.data.purpose },
              { label: "预留空间", value: formatBytes(plan.data.reservedBytes, 1) },
              { label: "说明", value: planReasonText(plan.data.statusReason), wide: true },
            ]}
          />
          <JsonView className="mt-2" label="评估依据" value={plan.data.evaluation} />
        </DetailSection>
      ) : null}

      {task.fileList?.length ? (
        <DetailSection title={`文件(${task.fileList.length})`}>
          <ul className="max-h-60 space-y-1 overflow-auto text-meta">
            {task.fileList.map((f) => (
              <li key={f.path} className="flex justify-between gap-3">
                <span className="min-w-0 font-mono break-all text-foreground">{f.path}</span>
                <span className="shrink-0 text-muted-foreground tabular-nums">
                  {formatBytes(f.size, 1)}
                  {f.progress !== undefined ? ` · ${Math.round(f.progress * 100)}%` : ""}
                </span>
              </li>
            ))}
          </ul>
        </DetailSection>
      ) : null}

      {task.lastError ? <JsonView label="下载器错误" value={task.lastError} tone="destructive" defaultOpen /> : null}

      {organizing ? (
        <OrganizeWizard
          source={{
            kind: "download",
            taskId: task.id,
            instanceId: task.instanceId,
            contentPath: task.contentPath,
            name: task.name,
          }}
          onClose={() => setOrganizing(false)}
        />
      ) : null}
    </div>
  );
}