Merge branch 'errors-fold-drag'

Smart fold-around-errors with drag-to-reveal handle. Default ±25
context per error, draggable bars between gaps, click-to-reveal-25
fallback.

web/public/css/iblogs.css

@@ -1088,6 +1088,71 @@ main {
     color: var(--accent);
 }
 
+/*
+ * Foldable variant — generated by the smart "errors + 25 context" toggle in
+ * log.js. The bar is draggable: vertical pointer drag reveals or re-hides
+ * lines from the top of the hidden range. Visual cues:
+ *   - ns-resize cursor announces the drag direction.
+ *   - Faint horizontal hatch hints at compressed content underneath.
+ *   - Hover and drag states intensify the hatch toward --accent so the
+ *     bar reads as an interactive separator, not decorative chrome.
+ */
+.collapsed-lines-foldable {
+    cursor: ns-resize;
+    user-select: none;
+    -webkit-user-select: none;
+}
+
+.collapsed-lines-foldable .collapsed-lines-count {
+    background:
+        repeating-linear-gradient(
+            to bottom,
+            transparent 0,
+            transparent 3px,
+            color-mix(in srgb, var(--border) 60%, transparent) 3px,
+            color-mix(in srgb, var(--border) 60%, transparent) 4px
+        ),
+        var(--surface);
+    border-top: 1px solid var(--border);
+    border-bottom: 1px solid var(--border);
+    transition:
+        background-color 0.12s ease,
+        color 0.12s ease,
+        border-color 0.12s ease,
+        box-shadow 0.12s ease;
+}
+
+.collapsed-lines-foldable:hover .collapsed-lines-count,
+.collapsed-lines-dragging .collapsed-lines-count {
+    background:
+        repeating-linear-gradient(
+            to bottom,
+            transparent 0,
+            transparent 3px,
+            color-mix(in srgb, var(--accent) 35%, transparent) 3px,
+            color-mix(in srgb, var(--accent) 35%, transparent) 4px
+        ),
+        var(--accent-bg);
+    border-top-color: color-mix(in srgb, var(--accent) 60%, transparent);
+    border-bottom-color: color-mix(in srgb, var(--accent) 60%, transparent);
+    color: var(--accent);
+}
+
+.collapsed-lines-foldable:hover .collapsed-lines-count i,
+.collapsed-lines-dragging .collapsed-lines-count i {
+    color: var(--accent);
+}
+
+.collapsed-lines-dragging {
+    cursor: grabbing;
+}
+
+.collapsed-lines-dragging .collapsed-lines-count {
+    box-shadow:
+        inset 0 0 0 1px color-mix(in srgb, var(--accent) 70%, transparent),
+        0 6px 16px color-mix(in srgb, var(--accent) 25%, transparent);
+}
+
 .log-inner .level {
     display: block;
     white-space: pre-wrap;

web/public/js/log.js

@@ -47,7 +47,20 @@ function scrollToHeight(top, smoothScrollLimit = 10000) {
     window.scrollTo({left: 0, top, behavior});
 }
 
-/* error collapse toggle */
+/*
+ * Error collapse toggle.
+ *
+ * Smart fold: every entry within ±ERROR_WINDOW_SIZE of an error stays
+ * visible; runs of non-error entries with no nearby errors collapse into
+ * a draggable fold bar. Vertical drag on the bar progressively reveals or
+ * re-hides lines; a click without drag reveals the next DEFAULT_CLICK_REVEAL
+ * lines.
+ */
+const ERROR_WINDOW_SIZE = 25;
+const PIXELS_PER_LINE_DRAG = 6;
+const DEFAULT_CLICK_REVEAL = 25;
+const DRAG_PIXEL_THRESHOLD = 3;
+
 const toggleErrorsButton = document.getElementById("error-toggle");
 if (toggleErrorsButton) {
     toggleErrorsButton.addEventListener("click", toggleErrors);
@@ -64,76 +77,134 @@ function toggleErrors() {
 }
 
 function collapseAllErrors() {
-    let firstNoErrorLine = false;
-    let lines = document.querySelectorAll('.log-inner > .entry');
-    let totalLines = lines.length;
-    for (const [i, line] of lines.entries()) {
-        let lineNumber = line.querySelector(".line-number").innerHTML;
-        if (line.classList.contains("entry-no-error")) {
-            line.style.display = "none";
+    const lines = Array.from(document.querySelectorAll('.log-inner > .entry'));
+    const total = lines.length;
+    if (!total) return;
 
-            if (firstNoErrorLine === false) {
-                firstNoErrorLine = lineNumber;
-            }
-
-            if (i + 1 === totalLines && firstNoErrorLine) {
-                line.insertAdjacentElement("afterend", generateCollapsedLines(firstNoErrorLine, lineNumber));
-            }
-        } else {
-            if (firstNoErrorLine) {
-                line.insertAdjacentElement("beforebegin", generateCollapsedLines(firstNoErrorLine, lineNumber - 1));
-                firstNoErrorLine = false;
-            }
+    // Pass 1: mark entries within ±ERROR_WINDOW_SIZE of any error.
+    const mustShow = new Array(total).fill(false);
+    for (let i = 0; i < total; i++) {
+        if (lines[i].classList.contains("entry-error")) {
+            const lo = Math.max(0, i - ERROR_WINDOW_SIZE);
+            const hi = Math.min(total - 1, i + ERROR_WINDOW_SIZE);
+            for (let j = lo; j <= hi; j++) mustShow[j] = true;
         }
     }
+
+    // Pass 2: hide unmarked entries; emit a fold bar at the START of each run.
+    let runEntries = [];
+    const flushRun = () => {
+        if (!runEntries.length) return;
+        const bar = createFoldBar(runEntries);
+        runEntries[0].insertAdjacentElement("beforebegin", bar);
+        runEntries = [];
+    };
+    for (let i = 0; i < total; i++) {
+        if (!mustShow[i]) {
+            lines[i].style.display = "none";
+            runEntries.push(lines[i]);
+        } else {
+            flushRun();
+        }
+    }
+    flushRun();
 }
 
 function uncollapseAllErrors() {
-    document.querySelectorAll('.entry-no-error').forEach(line => line.style.removeProperty("display"));
-    document.querySelectorAll('.collapsed-lines').forEach(collapsed => collapsed.remove());
+    document.querySelectorAll(".log-inner > .entry").forEach(line => line.style.removeProperty("display"));
+    document.querySelectorAll(".collapsed-lines").forEach(bar => bar.remove());
 }
 
-function handleCollapsedClick(e) {
-    let collapsed = e.currentTarget;
-    let positionElement = document.getElementById(`L${parseInt(collapsed.dataset.end) + 1}`);
-    let position;
-    if (positionElement) {
-        position = positionElement.getBoundingClientRect().top - window.scrollY;
-    }
-    for (let i = parseInt(collapsed.dataset.start); i <= parseInt(collapsed.dataset.end); i++) {
-        document.getElementById(`L${i}`).parentElement.parentElement.style.removeProperty("display");
-    }
-    if (positionElement) {
-        window.scrollTo({
-            left: 0,
-            top: positionElement.getBoundingClientRect().top - position - collapsed.offsetHeight,
-            behavior: "instant"
-        });
-    }
-    collapsed.remove();
+function createFoldBar(entries) {
+    const bar = document.createElement("div");
+    bar.classList.add("collapsed-lines", "collapsed-lines-foldable");
+    bar.appendChild(document.createElement("div")); // line-number column slot
+
+    const count = document.createElement("div");
+    count.classList.add("collapsed-lines-count");
+    bar.appendChild(count);
+
+    bar._hiddenEntries = entries;
+    bar._revealedCount = 0;
+    renderFoldLabel(bar);
+    attachFoldDragHandler(bar);
+    return bar;
 }
 
-function generateCollapsedLines(start, end) {
-    let count = end - start + 1;
-    let string = count === 1 ? "line" : "lines";
+function renderFoldLabel(bar) {
+    const entries = bar._hiddenEntries;
+    const total = entries.length;
+    const revealed = bar._revealedCount;
+    const remaining = total - revealed;
+    const count = bar.querySelector(".collapsed-lines-count");
+    count.replaceChildren();
 
-    let collapsedRow = document.createElement("div");
-    collapsedRow.classList.add("collapsed-lines");
-    collapsedRow.dataset.start = start;
-    collapsedRow.dataset.end = end;
-    collapsedRow.appendChild(document.createElement("div"));
-    collapsedRow.addEventListener("click", handleCollapsedClick);
+    if (remaining <= 0) return;
 
-    let collapsedLinesCount = document.createElement("div");
-    collapsedLinesCount.classList.add("collapsed-lines-count");
-    let icon = document.createElement("i");
-    icon.classList.add("fa-solid", "fa-angle-up");
-    collapsedLinesCount.appendChild(icon);
-    collapsedLinesCount.append(` ${count} ${string} `);
-    collapsedLinesCount.append(icon.cloneNode());
-    collapsedRow.appendChild(collapsedLinesCount);
+    const firstHiddenLine = parseInt(entries[revealed].querySelector(".line-number").innerHTML, 10);
+    const lastHiddenLine = parseInt(entries[total - 1].querySelector(".line-number").innerHTML, 10);
+    const word = remaining === 1 ? "line" : "lines";
 
-    return collapsedRow;
+    const grip = document.createElement("i");
+    grip.className = "fa-solid fa-grip-lines";
+    count.appendChild(grip);
+    count.append(` ${remaining} ${word} hidden · ${firstHiddenLine}–${lastHiddenLine} · drag to reveal `);
+    count.appendChild(grip.cloneNode());
+}
+
+function applyFoldReveal(bar, n) {
+    const entries = bar._hiddenEntries;
+    n = Math.max(0, Math.min(entries.length, n));
+    if (n === bar._revealedCount) return;
+    for (let i = 0; i < entries.length; i++) {
+        if (i < n) entries[i].style.removeProperty("display");
+        else entries[i].style.display = "none";
+    }
+    bar._revealedCount = n;
+    renderFoldLabel(bar);
+}
+
+function attachFoldDragHandler(bar) {
+    let dragging = false;
+    let dragStartY = 0;
+    let dragStartReveal = 0;
+    let didDrag = false;
+
+    bar.addEventListener("pointerdown", (e) => {
+        if (e.button !== 0) return;
+        dragging = true;
+        didDrag = false;
+        dragStartY = e.clientY;
+        dragStartReveal = bar._revealedCount;
+        bar.setPointerCapture(e.pointerId);
+        bar.classList.add("collapsed-lines-dragging");
+        e.preventDefault();
+    });
+
+    bar.addEventListener("pointermove", (e) => {
+        if (!dragging) return;
+        const dy = e.clientY - dragStartY;
+        if (Math.abs(dy) >= DRAG_PIXEL_THRESHOLD) didDrag = true;
+        const target = dragStartReveal + Math.round(dy / PIXELS_PER_LINE_DRAG);
+        applyFoldReveal(bar, target);
+    });
+
+    const finish = (e) => {
+        if (!dragging) return;
+        dragging = false;
+        try { bar.releasePointerCapture(e.pointerId); } catch {}
+        bar.classList.remove("collapsed-lines-dragging");
+
+        if (!didDrag) {
+            // Plain click: reveal the next chunk of lines.
+            applyFoldReveal(bar, bar._revealedCount + DEFAULT_CLICK_REVEAL);
+        }
+        if (bar._revealedCount >= bar._hiddenEntries.length) {
+            bar.remove();
+        }
+    };
+    bar.addEventListener("pointerup", finish);
+    bar.addEventListener("pointercancel", finish);
 }
 
 /* convert timestamps */