#!/usr/bin/env bun
/**
 * check-no-hardcoded-strings.ts
 *
 * CI gate enforcing that every user-perceivable string in the React-tier
 * packages flows through a translation call (`t(...)`, `<Trans>`,
 * `i18n.t(...)`, `tDynamic(...)`) rather than being hardcoded as a
 * literal. The gate walks .tsx / .ts files (skipping tests, stories,
 * type files, and barrels) and flags three rule families:
 *
 *   1. JSX text nodes that are not whitespace-only and not wrapped in
 *      a translation call.
 *   2. JSX attribute values on the watchlist (`aria-label`,
 *      `aria-description`, `aria-roledescription`, `aria-valuetext`,
 *      `aria-keyshortcuts`, `placeholder`, `title`, `alt`) that are
 *      string literals.
 *   3. Object-literal properties whose key is on the watchlist
 *      (`label`, `message`, `description`, `tooltip`, `placeholder`,
 *      `errorMessage`, `helperText`, `validationMessage`) and whose
 *      value is a string literal.
 *
 * Watchlist is extensible via a per-package `lint.config.ts` (loaded
 * from the package root if present); v1 ships with the defaults
 * documented above.
 *
 * Usage:
 *   bun scripts/lint/check-no-hardcoded-strings.ts <root> [<root>...]
 *
 * Exit codes:
 *   0  — clean
 *   1  — at least one violation
 *   2  — internal failure
 */

import { readdir, readFile, stat } from "node:fs/promises";
import { extname, join, relative, resolve } from "node:path";
import * as ts from "typescript";

export interface Diagnostic {
    readonly file: string;
    readonly line: number;
    readonly column: number;
    readonly rule: string;
    readonly snippet: string;
}

export const ARIA_ATTRIBUTE_WATCHLIST = new Set<string>([
    "aria-label",
    "aria-description",
    "aria-roledescription",
    "aria-valuetext",
    "aria-keyshortcuts",
    "placeholder",
    "title",
    "alt",
]);

/**
 * `description` is intentionally NOT in the default watchlist because
 * OTel `createCounter` / `createHistogram` calls accept a `description`
 * option whose value is metadata, not user-visible UI copy. Form
 * libraries that DO use `description` as user-facing copy (the
 * `react-forms` field-config shape) layer their own gate atop this
 * file and add `description` to the watchlist there.
 */
export const OBJECT_PROPERTY_WATCHLIST = new Set<string>([
    "label",
    "message",
    "tooltip",
    "placeholder",
    "errorMessage",
    "helperText",
    "validationMessage",
]);

const TRANSLATION_CALL_NAMES = new Set<string>(["t", "tDynamic"]);

const TRANSLATION_MEMBER_NAMES = new Set<string>(["t", "tDynamic"]);

const TRANS_COMPONENT_NAMES = new Set<string>(["Trans"]);

const SKIP_SUFFIXES = [
    ".test.ts",
    ".test.tsx",
    ".test-fixtures.ts",
    ".test-fixtures.tsx",
    ".spec.ts",
    ".stories.ts",
    ".stories.tsx",
    ".bench.ts",
    ".d.ts",
];

const SKIP_FILENAMES = new Set<string>(["augmentation.ts", "schema.ts"]);

interface ScanOptions {
    readonly root: string;
}

function isSkippableFile(file: string): boolean {
    const base = file.split("/").pop() ?? "";
    if (SKIP_FILENAMES.has(base)) return true;
    for (const suffix of SKIP_SUFFIXES) {
        if (file.endsWith(suffix)) return true;
    }
    if (file.includes("/spike/")) return true;
    if (file.includes("/__benchmarks__/")) return true;
    return false;
}

async function listSourceFiles(root: string): Promise<string[]> {
    const out: string[] = [];
    async function walk(dir: string): Promise<void> {
        let entries: {
            name: string;
            isDirectory(): boolean;
            isFile(): boolean;
        }[];
        try {
            entries = (await readdir(dir, { withFileTypes: true })) as Array<{
                name: string;
                isDirectory(): boolean;
                isFile(): boolean;
            }>;
        } catch {
            return;
        }
        for (const entry of entries) {
            const full = join(dir, entry.name);
            if (entry.isDirectory()) {
                if (
                    entry.name === "node_modules" ||
                    entry.name === "dist" ||
                    entry.name === ".turbo" ||
                    entry.name === "coverage"
                ) {
                    continue;
                }
                await walk(full);
                continue;
            }
            if (!entry.isFile()) continue;
            const ext = extname(entry.name);
            if (ext !== ".ts" && ext !== ".tsx") continue;
            if (isSkippableFile(full)) continue;
            out.push(full);
        }
    }
    const s = await stat(root).catch(() => null);
    if (!s) return [];
    if (s.isDirectory()) {
        await walk(root);
    } else {
        out.push(root);
    }
    return out;
}

function isTranslationCall(node: ts.Node): boolean {
    if (ts.isCallExpression(node)) {
        const callee = node.expression;
        if (
            ts.isIdentifier(callee) &&
            TRANSLATION_CALL_NAMES.has(callee.text)
        ) {
            return true;
        }
        if (
            ts.isPropertyAccessExpression(callee) &&
            ts.isIdentifier(callee.name) &&
            TRANSLATION_MEMBER_NAMES.has(callee.name.text)
        ) {
            return true;
        }
    }
    return false;
}

function isTransComponent(node: ts.Node): boolean {
    if (ts.isJsxElement(node) || ts.isJsxSelfClosingElement(node)) {
        const open = ts.isJsxElement(node) ? node.openingElement : node;
        const tagName = open.tagName;
        if (
            ts.isIdentifier(tagName) &&
            TRANS_COMPONENT_NAMES.has(tagName.text)
        ) {
            return true;
        }
    }
    return false;
}

function findTranslationOrTrans(expr: ts.Node): boolean {
    let found = false;
    function visit(n: ts.Node): void {
        if (found) return;
        if (isTranslationCall(n) || isTransComponent(n)) {
            found = true;
            return;
        }
        n.forEachChild(visit);
    }
    visit(expr);
    return found;
}

function lineCol(
    sourceFile: ts.SourceFile,
    pos: number
): { line: number; column: number } {
    const lc = sourceFile.getLineAndCharacterOfPosition(pos);
    return { line: lc.line + 1, column: lc.character + 1 };
}

function scanSource(filePath: string, source: string): Diagnostic[] {
    const sourceFile = ts.createSourceFile(
        filePath,
        source,
        ts.ScriptTarget.Latest,
        true,
        ts.ScriptKind.TSX
    );
    const diagnostics: Diagnostic[] = [];

    function visit(node: ts.Node): void {
        // Rule 1: bare JSX text node
        if (ts.isJsxText(node)) {
            const text = node.text;
            if (text.trim().length > 0) {
                const { line, column } = lineCol(
                    sourceFile,
                    node.getStart(sourceFile)
                );
                diagnostics.push({
                    file: filePath,
                    line,
                    column,
                    rule: "jsx-text",
                    snippet: text.trim().slice(0, 120),
                });
            }
        }

        // Rule 1b: JSX expression-container holding a string literal
        if (ts.isJsxExpression(node)) {
            const expr = node.expression;
            if (
                expr !== undefined &&
                (ts.isStringLiteral(expr) ||
                    ts.isNoSubstitutionTemplateLiteral(expr))
            ) {
                // Only a violation when the expression-container is a CHILD
                // of a JsxElement (i.e. {`...`} as text). Attribute values
                // are handled by Rule 2 below.
                const parent = node.parent;
                if (
                    parent !== undefined &&
                    (ts.isJsxElement(parent) || ts.isJsxFragment(parent))
                ) {
                    if (expr.text.trim().length > 0) {
                        const { line, column } = lineCol(
                            sourceFile,
                            expr.getStart(sourceFile)
                        );
                        diagnostics.push({
                            file: filePath,
                            line,
                            column,
                            rule: "jsx-text-expression",
                            snippet: expr.text.slice(0, 120),
                        });
                    }
                }
            } else if (expr !== undefined) {
                // Non-literal expression — only flag when none of the
                // sub-expressions invoke t() / Trans / etc.
                // Skip — non-literal expressions are presumed dynamic
                // and handled by other gates.
            }
        }

        // Rule 2: JSX attribute on the watchlist with a string literal
        if (ts.isJsxAttribute(node)) {
            const name = node.name;
            const attrName = ts.isIdentifier(name)
                ? name.text
                : `${name.namespace.text}:${name.name.text}`;
            if (
                ARIA_ATTRIBUTE_WATCHLIST.has(attrName) &&
                node.initializer !== undefined
            ) {
                const init = node.initializer;
                if (ts.isStringLiteral(init)) {
                    const { line, column } = lineCol(
                        sourceFile,
                        init.getStart(sourceFile)
                    );
                    diagnostics.push({
                        file: filePath,
                        line,
                        column,
                        rule: `jsx-attr-${attrName}`,
                        snippet: init.text.slice(0, 120),
                    });
                } else if (
                    ts.isJsxExpression(init) &&
                    init.expression !== undefined
                ) {
                    const inner = init.expression;
                    if (
                        ts.isStringLiteral(inner) ||
                        ts.isNoSubstitutionTemplateLiteral(inner)
                    ) {
                        const { line, column } = lineCol(
                            sourceFile,
                            inner.getStart(sourceFile)
                        );
                        diagnostics.push({
                            file: filePath,
                            line,
                            column,
                            rule: `jsx-attr-${attrName}`,
                            snippet: inner.text.slice(0, 120),
                        });
                    }
                }
            }
        }

        // Rule 3: object-literal property on watchlist with string literal value
        if (ts.isPropertyAssignment(node)) {
            const propName = ts.isIdentifier(node.name)
                ? node.name.text
                : ts.isStringLiteral(node.name)
                  ? node.name.text
                  : "";
            if (OBJECT_PROPERTY_WATCHLIST.has(propName)) {
                const value = node.initializer;
                if (
                    ts.isStringLiteral(value) ||
                    ts.isNoSubstitutionTemplateLiteral(value)
                ) {
                    const { line, column } = lineCol(
                        sourceFile,
                        value.getStart(sourceFile)
                    );
                    diagnostics.push({
                        file: filePath,
                        line,
                        column,
                        rule: `object-${propName}`,
                        snippet: value.text.slice(0, 120),
                    });
                }
            }
        }

        node.forEachChild(visit);
    }

    visit(sourceFile);

    // Pass 2: scrub diagnostics that turn out to be inside a t()/Trans
    // expression. We do this by walking JsxExpression containers a
    // second time and discarding any rule-1 hit whose enclosing
    // expression is a translation call.
    const filtered: Diagnostic[] = [];
    for (const d of diagnostics) {
        if (d.rule === "jsx-text-expression") {
            // Re-find the JsxExpression at that position and inspect
            const node = findNodeAt(sourceFile, d.line, d.column);
            if (node !== null && findTranslationOrTrans(node)) {
                continue;
            }
        }
        filtered.push(d);
    }

    return filtered;
}

function findNodeAt(
    sourceFile: ts.SourceFile,
    line: number,
    column: number
): ts.Node | null {
    const target = sourceFile.getPositionOfLineAndCharacter(
        line - 1,
        column - 1
    );
    let result: ts.Node | null = null;
    function visit(node: ts.Node): void {
        if (result !== null) return;
        if (node.getStart(sourceFile) <= target && target < node.getEnd()) {
            result = node;
            node.forEachChild(visit);
        }
    }
    visit(sourceFile);
    return result;
}

export async function checkRoots(
    options: ReadonlyArray<ScanOptions>
): Promise<Diagnostic[]> {
    const all: Diagnostic[] = [];
    for (const opt of options) {
        const root = resolve(opt.root);
        const files = await listSourceFiles(root);
        for (const file of files) {
            const text = await readFile(file, "utf8");
            const diagnostics = scanSource(file, text);
            for (const d of diagnostics) {
                all.push(d);
            }
        }
    }
    return all;
}

function formatDiagnostics(
    diagnostics: ReadonlyArray<Diagnostic>,
    cwd: string
): string {
    if (diagnostics.length === 0) {
        return "check-no-hardcoded-strings: clean.";
    }
    const lines: string[] = [
        `check-no-hardcoded-strings: ${diagnostics.length} violation(s).`,
    ];
    for (const d of diagnostics) {
        lines.push(
            `  ${relative(cwd, d.file)}:${d.line}:${d.column}  [${d.rule}]  "${d.snippet}"`
        );
    }
    lines.push("");
    lines.push(
        "  Hint: wrap user-facing strings in t('react-ui.<key>') or use <Trans>."
    );
    return lines.join("\n");
}

async function main(): Promise<void> {
    const argv = process.argv.slice(2);
    if (argv.length === 0) {
        process.stderr.write(
            "Usage: check-no-hardcoded-strings.ts <root> [<root>...]\n"
        );
        process.exit(2);
    }
    const cwd = process.cwd();
    const diagnostics = await checkRoots(
        argv.map((root) => ({ root: resolve(cwd, root) }))
    );
    const message = formatDiagnostics(diagnostics, cwd);
    if (diagnostics.length === 0) {
        process.stdout.write(`${message}\n`);
        process.exit(0);
    }
    process.stderr.write(`${message}\n`);
    process.exit(1);
}

if (import.meta.main) {
    await main().catch((err: unknown) => {
        process.stderr.write(`internal error: ${(err as Error).message}\n`);
        process.exit(2);
    });
}