优化一下博客的性能

themes/Ying/assets/js/modules/cache.js

@@ -0,0 +1,202 @@
+window.BrowserCache = (function () {
+    var PREFIX = 'ying-cache:';
+    var DEBUG_KEY = PREFIX + 'debug';
+    var DEBUG = detectDebug();
+
+    function detectDebug() {
+        try {
+            if (typeof window === 'undefined' || !window.location) return false;
+            var loc = window.location;
+            var host = loc.hostname || '';
+            var protocol = loc.protocol || '';
+            var search = loc.search || '';
+
+            // Explicit URL override wins over everything.
+            if (/(^|[?&])debug-cache=1(&|$)/.test(search)) return true;
+            if (/(^|[?&])debug-cache=0(&|$)/.test(search)) return false;
+
+            // Persisted toggle (set via setDebug) wins over auto-detection.
+            try {
+                var stored = localStorage.getItem(DEBUG_KEY);
+                if (stored === '1') return true;
+                if (stored === '0') return false;
+            } catch (e) {}
+
+            // Auto-enable on local dev origins.
+            if (protocol === 'file:') return true;
+            if (host === 'localhost' || host === '127.0.0.1' || host === '0.0.0.0') return true;
+        } catch (e) {}
+        return false;
+    }
+
+    function setDebug(enabled) {
+        DEBUG = !!enabled;
+        try {
+            localStorage.setItem(DEBUG_KEY, DEBUG ? '1' : '0');
+        } catch (e) {}
+        return DEBUG;
+    }
+
+    function isDebug() {
+        return DEBUG;
+    }
+
+    function isStorageAvailable() {
+        try {
+            var key = PREFIX + '__test__';
+            localStorage.setItem(key, '1');
+            localStorage.removeItem(key);
+            return true;
+        } catch (e) {
+            return false;
+        }
+    }
+
+    function buildKey(key) {
+        return PREFIX + key;
+    }
+
+    function log(tagOrEvent, payload) {
+        if (!DEBUG || typeof console === 'undefined' || !console.info) return;
+        var label = tagOrEvent && tagOrEvent.charAt(0) === '[' ? tagOrEvent : '[BrowserCache][' + tagOrEvent + ']';
+        console.info(label, payload || {});
+    }
+
+    function formatDuration(ms) {
+        if (!ms || ms <= 0) return '0s';
+        var totalSeconds = Math.floor(ms / 1000);
+        var hours = Math.floor(totalSeconds / 3600);
+        var minutes = Math.floor((totalSeconds % 3600) / 60);
+        var seconds = totalSeconds % 60;
+        if (hours > 0) return hours + 'h ' + minutes + 'm';
+        if (minutes > 0) return minutes + 'm ' + seconds + 's';
+        return seconds + 's';
+    }
+
+    function remove(key) {
+        if (!isStorageAvailable()) return;
+        try {
+            localStorage.removeItem(buildKey(key));
+            log('remove', { key: buildKey(key) });
+        } catch (e) {}
+    }
+
+    function read(key, options) {
+        options = options || {};
+        if (!isStorageAvailable()) {
+            log('storage-unavailable', { key: buildKey(key) });
+            return null;
+        }
+
+        var fullKey = buildKey(key);
+
+        try {
+            var raw = localStorage.getItem(fullKey);
+            if (!raw) {
+                log('miss', { key: fullKey });
+                return null;
+            }
+
+            var payload = JSON.parse(raw);
+            if (!payload || typeof payload !== 'object') {
+                remove(key);
+                log('invalid-payload', { key: fullKey });
+                return null;
+            }
+
+            if (payload.version !== options.version) {
+                remove(key);
+                log('version-mismatch', { key: fullKey, expected: options.version, actual: payload.version });
+                return null;
+            }
+
+            if (typeof payload.cachedAt !== 'number' || !('data' in payload)) {
+                remove(key);
+                log('invalid-shape', { key: fullKey });
+                return null;
+            }
+
+            if (typeof options.validate === 'function' && !options.validate(payload.data)) {
+                remove(key);
+                log('validate-failed', { key: fullKey });
+                return null;
+            }
+
+            var now = Date.now();
+            var age = now - payload.cachedAt;
+            var softTtl = options.softTtl || 0;
+            var hardTtl = options.hardTtl || softTtl;
+
+            if (hardTtl > 0 && age > hardTtl) {
+                remove(key);
+                log('expired', { key: fullKey, age: formatDuration(age), hardTtl: formatDuration(hardTtl) });
+                return null;
+            }
+
+            var result = {
+                key: fullKey,
+                data: payload.data,
+                cachedAt: payload.cachedAt,
+                age: age,
+                ageText: formatDuration(age),
+                softTtl: softTtl,
+                softTtlText: formatDuration(softTtl),
+                hardTtl: hardTtl,
+                hardTtlText: formatDuration(hardTtl),
+                isFresh: softTtl <= 0 || age <= softTtl,
+                isStale: softTtl > 0 && age > softTtl
+            };
+
+            log(result.isFresh ? 'hit-fresh' : 'hit-stale', {
+                key: fullKey,
+                age: result.ageText,
+                softTtl: result.softTtlText,
+                hardTtl: result.hardTtlText
+            });
+
+            return result;
+        } catch (e) {
+            remove(key);
+            log('parse-failed', { key: fullKey, message: e && e.message ? e.message : e });
+            return null;
+        }
+    }
+
+    function write(key, options, data) {
+        options = options || {};
+        if (!isStorageAvailable()) {
+            log('storage-unavailable', { key: buildKey(key) });
+            return;
+        }
+
+        var fullKey = buildKey(key);
+
+        try {
+            localStorage.setItem(fullKey, JSON.stringify({
+                version: options.version,
+                cachedAt: Date.now(),
+                data: data
+            }));
+            log('write', {
+                key: fullKey,
+                softTtl: formatDuration(options.softTtl || 0),
+                hardTtl: formatDuration(options.hardTtl || options.softTtl || 0)
+            });
+        } catch (e) {
+            if (DEBUG && typeof console !== 'undefined' && console.warn) {
+                console.warn('BrowserCache write failed:', e);
+            }
+        }
+    }
+
+    return {
+        read: read,
+        write: write,
+        remove: remove,
+        buildKey: buildKey,
+        formatDuration: formatDuration,
+        log: log,
+        setDebug: setDebug,
+        isDebug: isDebug
+    };
+})();