// Page count baseline check (ARCHITECTURE.md §10 P1-8 / §11.6)
//
// Asserts that the total page.tsx count never drops below the baseline.
// Prevents accidental route deletion. When adding new pages, update the
// baseline in BASELINE.total. Per-category minimums catch regressions
// in specific areas (dashboards, login, etc.).
//
// Usage: tsx scripts/check-page-count.ts
// Exit: 0 = pass, 1 = below baseline
//
// Related: ARCHITECTURE.md §10 P1-8, §11.6 验收纪律
import * as fs from "node:fs";
import * as path from "node:path";

const APP_DIR = path.resolve(process.cwd(), "src/app");

interface Baseline {
  total: number;
  categories: Record<string, { pattern: string; min: number; label: string }>;
}

// Baseline as of P2 B2 (2026-07-22, attendance + classes + students modules added).
// Update when adding pages.
const BASELINE: Baseline = {
  total: 48,
  categories: {
    dashboards: {
      pattern: "shell/{admin,teacher,student,parent}/page.tsx",
      min: 4,
      label: "Role dashboards (admin/teacher/student/parent)",
    },
    login: {
      pattern: "login/page.tsx",
      min: 1,
      label: "Login page",
    },
    root: {
      pattern: "page.tsx",
      min: 1,
      label: "Root redirect page",
    },
    forbidden: {
      pattern: "shell/forbidden/page.tsx",
      min: 1,
      label: "Forbidden page",
    },
    catchAll: {
      pattern: "shell/[[...route]]/page.tsx",
      min: 1,
      label: "Shell catch-all",
    },
    devTemplates: {
      pattern: "shell/dev/templates/**/page.tsx",
      min: 5,
      label: "Dev template pages",
    },
  },
};

function scanPages(): string[] {
  const pages: string[] = [];

  function walk(dir: string, base: string): void {
    const entries = fs.readdirSync(dir, { withFileTypes: true });
    for (const entry of entries) {
      const full = path.join(dir, entry.name);
      const rel = path.relative(base, full).replace(/\\/g, "/");
      if (entry.isDirectory()) {
        walk(full, base);
      } else if (entry.name === "page.tsx") {
        pages.push(rel);
      }
    }
  }

  walk(APP_DIR, APP_DIR);
  return pages.sort();
}

function matchGlob(pattern: string, relPath: string): boolean {
  // Glob → regex: ** (any path), * (within segment), {a,b} (alternation)
  let result = "";
  let i = 0;
  while (i < pattern.length) {
    const c = pattern[i];
    if (c === "*" && pattern[i + 1] === "*") {
      // ** — match anything including /; skip trailing /
      result += ".*";
      i += 2;
      if (pattern[i] === "/") i++;
    } else if (c === "*") {
      result += "[^/]*";
      i++;
    } else if (c === "{") {
      const end = pattern.indexOf("}", i);
      if (end === -1) {
        result += "\\{";
        i++;
      } else {
        const opts = pattern
          .slice(i + 1, end)
          .split(",")
          .map((s) => s.trim());
        result += `(${opts.join("|")})`;
        i = end + 1;
      }
    } else if (".+?^$()[]|\\".includes(c)) {
      result += `\\${c}`;
      i++;
    } else {
      result += c;
      i++;
    }
  }
  return new RegExp(`^${result}$`).test(relPath);
}

function main(): void {
  const pages = scanPages();
  const total = pages.length;

  console.log("=== Page Count Baseline Check ===");
  console.log(`Total page.tsx files: ${total} (baseline: ${BASELINE.total})`);
  console.log("");

  // Per-category check
  let categoryFail = false;
  for (const [, cat] of Object.entries(BASELINE.categories)) {
    const matched = pages.filter((p) => matchGlob(cat.pattern, p));
    const count = matched.length;
    const status = count >= cat.min ? "✅" : "❌";
    if (count < cat.min) categoryFail = true;
    console.log(`  ${status} ${cat.label}: ${count} (min ${cat.min})`);
  }
  console.log("");

  // Total check
  const totalOk = total >= BASELINE.total;
  if (!totalOk) {
    console.log(`❌ Total ${total} < baseline ${BASELINE.total}`);
  }

  // List all pages
  console.log("Pages:");
  for (const p of pages) {
    console.log(
      `  /${p.replace(/\/page\.tsx$/, "").replace(/^page\.tsx$/, "")}`,
    );
  }
  console.log("");

  if (!totalOk || categoryFail) {
    console.log("Result: FAIL");
    process.exit(1);
  } else {
    console.log(`Result: PASS (${total} pages, all categories meet minimum)`);
    process.exit(0);
  }
}

main();