import fs from "fs";
import path from "path";
import Link from "next/link";
import { PageHeader } from "@/components/page-header";
import { Card, CardContent } from "@/components/ui/card";
import { Badge } from "@/components/ui/badge";
import { ExtractedVerseCount } from "../extracted-verse-count";

type ChapterInfo = {
  number: number;
  title: string;
  totalVerses: number;
};

type CantoInfo = {
  number: number;
  title: string;
  totalChapters: number;
  chapters: ChapterInfo[];
};

type Intro = {
  book: string;
  title: string;
  author: string;
  totalCantos: number;
  cantos: CantoInfo[];
};

export default function SbPage() {
  const introPath = path.join(process.cwd(), "app/lib/books/sb/intro.json");
  const intro: Intro = JSON.parse(fs.readFileSync(introPath, "utf-8"));

  return (
    <div className="min-h-screen bg-background">
      <PageHeader>
        <Link
          href="/books"
          className="text-sm text-muted-foreground hover:text-foreground"
        >
          &larr; Books
        </Link>
        <h1 className="mt-3 text-3xl font-bold text-foreground">
          {intro.title}
        </h1>
        <p className="mt-1 text-muted-foreground">{intro.author}</p>
      </PageHeader>
      <main className="max-w-3xl mx-auto px-6 py-8">
        <Card className="divide-y divide-border">
          <CardContent className="p-0">
            <ul className="divide-y divide-border">
              {intro.cantos.map((canto) => {
                const totalVerses = canto.chapters.reduce(
                  (sum, ch) => sum + ch.totalVerses,
                  0,
                );
                return (
                  <li key={canto.number}>
                    <Link
                      href={`/books/sb/${canto.number}`}
                      className="flex items-center justify-between px-5 py-4 hover:bg-muted transition-colors"
                    >
                      <div>
                        <Badge variant="secondary" className="mb-1">
                          Canto {canto.number}
                        </Badge>
                        <p className="font-medium text-foreground">
                          {canto.title}
                        </p>
                      </div>
                      <span className="text-sm text-muted-foreground shrink-0 ml-4">
                        {canto.totalChapters} chapters ·{" "}
                        <ExtractedVerseCount
                          count={totalVerses}
                          label="extracted verses"
                        />
                      </span>
                    </Link>
                  </li>
                );
              })}
            </ul>
          </CardContent>
        </Card>
      </main>
    </div>
  );
}