// Adapted from agentui (https://github.com/ashish200729/agentui), components/agents/file-diff.tsx
// Copyright (c) 2026 Saurabh Chauhan. MIT License, see ./LICENSE-agentui.md
// 改造:新增/删除行底色 emerald/rose → success/destructive 洗层(并保留 +/− 符号,不只靠颜色);不做语法高亮(去 shiki);
// 折叠用 Disclosure;maxHeight 改 Tailwind 类;用于展示路径类变更(如整理记录的入库目标)。
import { ChevronDown, FileCode2 } from "lucide-react";
import { type ReactNode, useId, useState } from "react";
import { cn } from "~/lib/utils.ts";
import { CHEVRON_CLASS, Disclosure } from "./disclosure.tsx";

export type FileDiffLineType = "added" | "removed" | "context";

export interface FileDiffLine {
  id: string;
  type?: FileDiffLineType;
  content: ReactNode;
  /** 行尾附注(如状态) */
  note?: ReactNode;
}

function Count({ value, type }: { value: number; type: "added" | "removed" }) {
  if (!value) return null;
  return (
    <span className={cn("font-mono text-meta tabular-nums", type === "added" ? "text-success" : "text-destructive")}>
      {type === "added" ? "+" : "−"}
      {value}
    </span>
  );
}

export function FileDiff({
  file,
  lines,
  defaultOpen = true,
  maxHeightClassName = "max-h-56",
  className,
}: {
  file: ReactNode;
  lines: FileDiffLine[];
  defaultOpen?: boolean;
  maxHeightClassName?: string;
  className?: string;
}) {
  const id = useId();
  const [open, setOpen] = useState(defaultOpen);
  const added = lines.filter((l) => l.type === "added").length;
  const removed = lines.filter((l) => l.type === "removed").length;
  return (
    <div className={cn("w-full min-w-0 overflow-hidden rounded-lg border border-border/60 text-sm", className)}>
      <button
        type="button"
        aria-expanded={open}
        aria-controls={id}
        onClick={() => setOpen(!open)}
        className="flex h-8 w-full cursor-pointer items-center gap-2 px-2.5 text-left outline-none transition-colors duration-micro hover:bg-foreground/[0.03] focus-visible:ring-2 focus-visible:ring-ring"
      >
        <FileCode2 aria-hidden className="size-3.5 shrink-0 text-muted-foreground/70" />
        <span className="min-w-0 flex-1 truncate text-meta text-foreground/85">{file}</span>
        <Count value={added} type="added" />
        <Count value={removed} type="removed" />
        <ChevronDown aria-hidden className={cn("size-3.5", CHEVRON_CLASS, open && "rotate-180")} />
      </button>
      <Disclosure id={id} open={open}>
        <div className={cn("overflow-auto border-t border-border/50 py-1", maxHeightClassName)}>
          <ul className="font-mono text-meta leading-5">
            {lines.map((l) => (
              <li
                key={l.id}
                className={cn(
                  "grid grid-cols-[1.25rem_minmax(0,1fr)_auto] gap-1 pr-2.5",
                  l.type === "added" && "bg-success/[0.08]",
                  l.type === "removed" && "bg-destructive/[0.08]",
                )}
              >
                <span
                  aria-hidden
                  className={cn(
                    "text-center select-none",
                    l.type === "added"
                      ? "text-success"
                      : l.type === "removed"
                        ? "text-destructive"
                        : "text-muted-foreground/50",
                  )}
                >
                  {l.type === "added" ? "+" : l.type === "removed" ? "−" : " "}
                </span>
                <span className="min-w-0 break-all text-foreground/85">
                  <span className="sr-only">
                    {l.type === "added" ? "新增：" : l.type === "removed" ? "移除：" : ""}
                  </span>
                  {l.content}
                </span>
                {l.note ? <span className="shrink-0 font-sans text-muted-foreground">{l.note}</span> : null}
              </li>
            ))}
          </ul>
        </div>
      </Disclosure>
    </div>
  );
}