From 89d639e44e194e4bee524b29be7254a02f976881 Mon Sep 17 00:00:00 2001
From: retoor <retoor@molodetz.nl>
Date: Wed, 6 Aug 2025 15:33:13 +0200
Subject: [PATCH] New editor.

---
 src/snek/static/editor.js | 668 ++++++++++++++++++++++++++------------
 1 file changed, 468 insertions(+), 200 deletions(-)

diff --git a/src/snek/static/editor.js b/src/snek/static/editor.js
index 8ee3bd3..d1b3ae1 100644
--- a/src/snek/static/editor.js
+++ b/src/snek/static/editor.js
@@ -1,226 +1,494 @@
-import { NjetComponent} from "/njet.js"
+import { NjetComponent } from "/njet.js"
 
-    class NjetEditor extends NjetComponent {
-      constructor() {
-        super();
-        this.attachShadow({ mode: 'open' });
+class NjetEditor extends NjetComponent {
+  constructor() {
+    super();
+    this.attachShadow({ mode: 'open' });
 
-        const style = document.createElement('style');
-        style.textContent = `
-          #editor {
-            padding: 1rem;
-            outline: none;
-            white-space: pre-wrap;
-            line-height: 1.5;
-            height: 100%;
-            overflow-y: auto;
-            background: #1e1e1e;
-            color: #d4d4d4;
-          }
-          #command-line {
-            position: absolute;
-            bottom: 0;
-            left: 0;
-            width: 100%;
-            padding: 0.2rem 1rem;
-            background: #333;
-            color: #0f0;
-            display: none;
-            font-family: monospace;
-          }
-        `;
+    const style = document.createElement('style');
+    style.textContent = `
+      :host {
+        display: block;
+        position: relative;
+        height: 100%;
+        font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
+      }
+      
+      #editor {
+        padding: 1rem;
+        outline: none;
+        white-space: pre-wrap;
+        line-height: 1.5;
+        height: calc(100% - 30px);
+        overflow-y: auto;
+        background: #1e1e1e;
+        color: #d4d4d4;
+        font-size: 14px;
+        caret-color: #fff;
+      }
+      
+      #editor.insert-mode {
+        caret-color: #4ec9b0;
+      }
+      
+      #editor.visual-mode {
+        caret-color: #c586c0;
+      }
+      
+      #editor::selection {
+        background: #264f78;
+      }
+      
+      #status-bar {
+        position: absolute;
+        bottom: 0;
+        left: 0;
+        right: 0;
+        height: 30px;
+        background: #007acc;
+        color: #fff;
+        display: flex;
+        align-items: center;
+        padding: 0 1rem;
+        font-size: 12px;
+        font-weight: 500;
+      }
+      
+      #mode-indicator {
+        text-transform: uppercase;
+        margin-right: 20px;
+        font-weight: bold;
+      }
+      
+      #command-line {
+        position: absolute;
+        bottom: 30px;
+        left: 0;
+        width: 100%;
+        padding: 0.3rem 1rem;
+        background: #2d2d2d;
+        color: #d4d4d4;
+        display: none;
+        font-family: inherit;
+        border-top: 1px solid #3e3e3e;
+        font-size: 14px;
+      }
+      
+      #command-input {
+        background: transparent;
+        border: none;
+        color: inherit;
+        outline: none;
+        font-family: inherit;
+        font-size: inherit;
+        width: calc(100% - 20px);
+      }
+      
+      .visual-selection {
+        background: #264f78 !important;
+      }
+    `;
 
-        this.editor = document.createElement('div');
-        this.editor.id = 'editor';
-        this.editor.contentEditable = true;
-        this.editor.innerText = `Welcome to VimEditor Component
+    this.editor = document.createElement('div');
+    this.editor.id = 'editor';
+    this.editor.contentEditable = true;
+    this.editor.spellcheck = false;
+    this.editor.innerText = `Welcome to VimEditor Component
 Line 2 here
 Another line
 Try i, Esc, v, :, yy, dd, 0, $, gg, G, and p`;
 
-        this.cmdLine = document.createElement('div');
-        this.cmdLine.id = 'command-line';
-        this.shadowRoot.append(style, this.editor, this.cmdLine);
+    this.cmdLine = document.createElement('div');
+    this.cmdLine.id = 'command-line';
+    
+    const cmdPrompt = document.createElement('span');
+    cmdPrompt.textContent = ':';
+    
+    this.cmdInput = document.createElement('input');
+    this.cmdInput.id = 'command-input';
+    this.cmdInput.type = 'text';
+    
+    this.cmdLine.append(cmdPrompt, this.cmdInput);
 
-        this.mode = 'normal'; // normal | insert | visual | command
-        this.keyBuffer = '';
-        this.lastDeletedLine = '';
-        this.yankedLine = '';
+    this.statusBar = document.createElement('div');
+    this.statusBar.id = 'status-bar';
+    
+    this.modeIndicator = document.createElement('span');
+    this.modeIndicator.id = 'mode-indicator';
+    this.modeIndicator.textContent = 'NORMAL';
+    
+    this.statusBar.appendChild(this.modeIndicator);
 
-        this.editor.addEventListener('keydown', this.handleKeydown.bind(this));
-      }
+    this.shadowRoot.append(style, this.editor, this.cmdLine, this.statusBar);
 
-      connectedCallback() {
+    this.mode = 'normal';
+    this.keyBuffer = '';
+    this.lastDeletedLine = '';
+    this.yankedLine = '';
+    this.visualStartOffset = null;
+    this.visualEndOffset = null;
+
+    // Bind event handlers
+    this.handleKeydown = this.handleKeydown.bind(this);
+    this.handleCmdKeydown = this.handleCmdKeydown.bind(this);
+    this.updateVisualSelection = this.updateVisualSelection.bind(this);
+    
+    this.editor.addEventListener('keydown', this.handleKeydown);
+    this.cmdInput.addEventListener('keydown', this.handleCmdKeydown);
+    this.editor.addEventListener('beforeinput', this.handleBeforeInput.bind(this));
+  }
+
+  connectedCallback() {
+    this.editor.focus();
+  }
+
+  setMode(mode) {
+    this.mode = mode;
+    this.modeIndicator.textContent = mode.toUpperCase();
+    
+    // Update editor classes
+    this.editor.classList.remove('insert-mode', 'visual-mode', 'normal-mode');
+    this.editor.classList.add(`${mode}-mode`);
+    
+    if (mode === 'visual') {
+      this.visualStartOffset = this.getCaretOffset();
+      this.editor.addEventListener('selectionchange', this.updateVisualSelection);
+    } else {
+      this.clearVisualSelection();
+      this.editor.removeEventListener('selectionchange', this.updateVisualSelection);
+    }
+    
+    if (mode === 'command') {
+      this.cmdLine.style.display = 'block';
+      this.cmdInput.value = '';
+      this.cmdInput.focus();
+    } else {
+      this.cmdLine.style.display = 'none';
+      if (mode !== 'insert') {
+        // Keep focus on editor for all non-insert modes
         this.editor.focus();
       }
+    }
+  }
 
-      getCaretOffset() {
-        let caretOffset = 0;
-        const sel = this.shadowRoot.getSelection();
-        if (!sel || sel.rangeCount === 0) return 0;
+  updateVisualSelection() {
+    if (this.mode !== 'visual') return;
+    this.visualEndOffset = this.getCaretOffset();
+  }
 
-        const range = sel.getRangeAt(0);
-        const preCaretRange = range.cloneRange();
-        preCaretRange.selectNodeContents(this.editor);
-        preCaretRange.setEnd(range.endContainer, range.endOffset);
-        caretOffset = preCaretRange.toString().length;
-        return caretOffset;
+  clearVisualSelection() {
+    const sel = this.shadowRoot.getSelection();
+    if (sel) sel.removeAllRanges();
+    this.visualStartOffset = null;
+    this.visualEndOffset = null;
+  }
+
+  getCaretOffset() {
+    const sel = this.shadowRoot.getSelection();
+    if (!sel || sel.rangeCount === 0) return 0;
+
+    const range = sel.getRangeAt(0);
+    const preCaretRange = range.cloneRange();
+    preCaretRange.selectNodeContents(this.editor);
+    preCaretRange.setEnd(range.endContainer, range.endOffset);
+    return preCaretRange.toString().length;
+  }
+
+  setCaretOffset(offset) {
+    const textContent = this.editor.innerText;
+    offset = Math.max(0, Math.min(offset, textContent.length));
+    
+    const range = document.createRange();
+    const sel = this.shadowRoot.getSelection();
+    const walker = document.createTreeWalker(
+      this.editor, 
+      NodeFilter.SHOW_TEXT, 
+      null, 
+      false
+    );
+
+    let currentOffset = 0;
+    let node;
+    
+    while ((node = walker.nextNode())) {
+      const nodeLength = node.textContent.length;
+      if (currentOffset + nodeLength >= offset) {
+        range.setStart(node, offset - currentOffset);
+        range.collapse(true);
+        sel.removeAllRanges();
+        sel.addRange(range);
+        return;
       }
+      currentOffset += nodeLength;
+    }
+    
+    // If we couldn't find the position, set to end
+    if (this.editor.lastChild) {
+      range.selectNodeContents(this.editor.lastChild);
+      range.collapse(false);
+      sel.removeAllRanges();
+      sel.addRange(range);
+    }
+  }
 
-      setCaretOffset(offset) {
-        const range = document.createRange();
-        const sel = this.shadowRoot.getSelection();
-        const walker = document.createTreeWalker(this.editor, NodeFilter.SHOW_TEXT, null, false);
+  handleBeforeInput(e) {
+    if (this.mode !== 'insert') {
+      e.preventDefault();
+    }
+  }
 
-        let currentOffset = 0;
-        let node;
-        while ((node = walker.nextNode())) {
-          if (currentOffset + node.length >= offset) {
-            range.setStart(node, offset - currentOffset);
-            range.collapse(true);
-            sel.removeAllRanges();
-            sel.addRange(range);
-            return;
-          }
-          currentOffset += node.length;
+  handleCmdKeydown(e) {
+    if (e.key === 'Enter') {
+      e.preventDefault();
+      this.executeCommand(this.cmdInput.value);
+      this.setMode('normal');
+    } else if (e.key === 'Escape') {
+      e.preventDefault();
+      this.setMode('normal');
+    }
+  }
+
+  executeCommand(cmd) {
+    const trimmedCmd = cmd.trim();
+    
+    // Handle basic vim commands
+    if (trimmedCmd === 'w' || trimmedCmd === 'write') {
+      console.log('Save command (not implemented)');
+    } else if (trimmedCmd === 'q' || trimmedCmd === 'quit') {
+      console.log('Quit command (not implemented)');
+    } else if (trimmedCmd === 'wq' || trimmedCmd === 'x') {
+      console.log('Save and quit command (not implemented)');
+    } else if (/^\d+$/.test(trimmedCmd)) {
+      // Go to line number
+      const lineNum = parseInt(trimmedCmd, 10) - 1;
+      this.goToLine(lineNum);
+    }
+  }
+
+  goToLine(lineNum) {
+    const lines = this.editor.innerText.split('\n');
+    if (lineNum < 0 || lineNum >= lines.length) return;
+    
+    let offset = 0;
+    for (let i = 0; i < lineNum; i++) {
+      offset += lines[i].length + 1;
+    }
+    this.setCaretOffset(offset);
+  }
+
+  getCurrentLineInfo() {
+    const text = this.editor.innerText;
+    const caretPos = this.getCaretOffset();
+    const lines = text.split('\n');
+    
+    let charCount = 0;
+    for (let i = 0; i < lines.length; i++) {
+      if (caretPos <= charCount + lines[i].length) {
+        return {
+          lineIndex: i,
+          lines: lines,
+          lineStartOffset: charCount,
+          positionInLine: caretPos - charCount
+        };
+      }
+      charCount += lines[i].length + 1;
+    }
+    
+    return {
+      lineIndex: lines.length - 1,
+      lines: lines,
+      lineStartOffset: charCount - lines[lines.length - 1].length - 1,
+      positionInLine: 0
+    };
+  }
+
+  handleKeydown(e) {
+    if (this.mode === 'insert') {
+      if (e.key === 'Escape') {
+        e.preventDefault();
+        this.setMode('normal');
+        // Move cursor one position left (vim behavior)
+        const offset = this.getCaretOffset();
+        if (offset > 0) {
+          this.setCaretOffset(offset - 1);
         }
       }
+      return;
+    }
 
-      handleKeydown(e) {
-        const key = e.key;
+    if (this.mode === 'command') {
+      return; // Command mode input is handled by cmdInput
+    }
 
-        if (this.mode === 'insert') {
-          if (key === 'Escape') {
-            e.preventDefault();
-            this.mode = 'normal';
-            this.editor.blur();
-            this.editor.focus();
-          }
-          return;
+    if (this.mode === 'visual') {
+      if (e.key === 'Escape') {
+        e.preventDefault();
+        this.setMode('normal');
+        return;
+      }
+      
+      // Allow movement in visual mode
+      if (['ArrowLeft', 'ArrowRight', 'ArrowUp', 'ArrowDown'].includes(e.key)) {
+        return; // Let default behavior handle selection
+      }
+      
+      if (e.key === 'y') {
+        e.preventDefault();
+        // Yank selected text
+        const sel = this.shadowRoot.getSelection();
+        if (sel && sel.rangeCount > 0) {
+          this.yankedLine = sel.toString();
         }
-
-        if (this.mode === 'command') {
-          if (key === 'Enter' || key === 'Escape') {
-            e.preventDefault();
-            this.cmdLine.style.display = 'none';
-            this.mode = 'normal';
-            this.keyBuffer = '';
-          }
-          return;
-        }
-
-        if (this.mode === 'visual') {
-          if (key === 'Escape') {
-            e.preventDefault();
-            this.mode = 'normal';
-          }
-          return;
-        }
-
-        // Handle normal mode
-        this.keyBuffer += key;
-
-        const text = this.editor.innerText;
-        const caretPos = this.getCaretOffset();
-        const lines = text.split('\n');
-
-        let charCount = 0, lineIdx = 0;
-        for (let i = 0; i < lines.length; i++) {
-          if (caretPos <= charCount + lines[i].length) {
-            lineIdx = i;
-            break;
-          }
-          charCount += lines[i].length + 1;
-        }
-
-        const offsetToLine = idx =>
-          text.split('\n').slice(0, idx).reduce((acc, l) => acc + l.length + 1, 0);
-
-        switch (this.keyBuffer) {
-          case 'i':
-            e.preventDefault();
-            this.mode = 'insert';
-            this.keyBuffer = '';
-            break;
-
-          case 'v':
-            e.preventDefault();
-            this.mode = 'visual';
-            this.keyBuffer = '';
-            break;
-
-          case ':':
-            e.preventDefault();
-            this.mode = 'command';
-            this.cmdLine.style.display = 'block';
-            this.cmdLine.textContent = ':';
-            this.keyBuffer = '';
-            break;
-
-          case 'yy':
-            e.preventDefault();
-            this.yankedLine = lines[lineIdx];
-            this.keyBuffer = '';
-            break;
-
-          case 'dd':
-            e.preventDefault();
-            this.lastDeletedLine = lines[lineIdx];
-            lines.splice(lineIdx, 1);
-            this.editor.innerText = lines.join('\n');
-            this.setCaretOffset(offsetToLine(lineIdx));
-            this.keyBuffer = '';
-            break;
-
-          case 'p':
-            e.preventDefault();
-            const lineToPaste = this.yankedLine || this.lastDeletedLine;
-            if (lineToPaste) {
-              lines.splice(lineIdx + 1, 0, lineToPaste);
-              this.editor.innerText = lines.join('\n');
-              this.setCaretOffset(offsetToLine(lineIdx + 1));
-            }
-            this.keyBuffer = '';
-            break;
-
-          case '0':
-            e.preventDefault();
-            this.setCaretOffset(offsetToLine(lineIdx));
-            this.keyBuffer = '';
-            break;
-
-          case '$':
-            e.preventDefault();
-            this.setCaretOffset(offsetToLine(lineIdx) + lines[lineIdx].length);
-            this.keyBuffer = '';
-            break;
-
-          case 'gg':
-            e.preventDefault();
-            this.setCaretOffset(0);
-            this.keyBuffer = '';
-            break;
-
-          case 'G':
-            e.preventDefault();
-            this.setCaretOffset(text.length);
-            this.keyBuffer = '';
-            break;
-
-          case 'Escape':
-            e.preventDefault();
-            this.mode = 'normal';
-            this.keyBuffer = '';
-            this.cmdLine.style.display = 'none';
-            break;
-
-          default:
-            // allow up to 2 chars for combos
-            if (this.keyBuffer.length > 2) this.keyBuffer = '';
-            break;
+        this.setMode('normal');
+        return;
+      }
+      
+      if (e.key === 'd' || e.key === 'x') {
+        e.preventDefault();
+        // Delete selected text
+        const sel = this.shadowRoot.getSelection();
+        if (sel && sel.rangeCount > 0) {
+          this.lastDeletedLine = sel.toString();
+          document.execCommand('delete');
         }
+        this.setMode('normal');
+        return;
       }
     }
 
-    customElements.define('njet-editor', NjetEditor);
-export {NjetEditor}
+    // Normal mode handling
+    e.preventDefault();
+    
+    // Special keys that should be handled immediately
+    if (e.key === 'Escape') {
+      this.keyBuffer = '';
+      this.setMode('normal');
+      return;
+    }
+    
+    // Build key buffer for commands
+    this.keyBuffer += e.key;
+    
+    const lineInfo = this.getCurrentLineInfo();
+    const { lineIndex, lines, lineStartOffset, positionInLine } = lineInfo;
+
+    // Process commands
+    switch (this.keyBuffer) {
+      case 'i':
+        this.keyBuffer = '';
+        this.setMode('insert');
+        break;
+
+      case 'a':
+        this.keyBuffer = '';
+        this.setCaretOffset(this.getCaretOffset() + 1);
+        this.setMode('insert');
+        break;
+
+      case 'v':
+        this.keyBuffer = '';
+        this.setMode('visual');
+        break;
+
+      case ':':
+        this.keyBuffer = '';
+        this.setMode('command');
+        break;
+
+      case 'yy':
+        this.keyBuffer = '';
+        this.yankedLine = lines[lineIndex];
+        break;
+
+      case 'dd':
+        this.keyBuffer = '';
+        this.lastDeletedLine = lines[lineIndex];
+        lines.splice(lineIndex, 1);
+        if (lines.length === 0) lines.push('');
+        this.editor.innerText = lines.join('\n');
+        this.setCaretOffset(lineStartOffset);
+        break;
+
+      case 'p':
+        this.keyBuffer = '';
+        const lineToPaste = this.yankedLine || this.lastDeletedLine;
+        if (lineToPaste) {
+          lines.splice(lineIndex + 1, 0, lineToPaste);
+          this.editor.innerText = lines.join('\n');
+          this.setCaretOffset(lineStartOffset + lines[lineIndex].length + 1);
+        }
+        break;
+
+      case '0':
+        this.keyBuffer = '';
+        this.setCaretOffset(lineStartOffset);
+        break;
+
+      case '$':
+        this.keyBuffer = '';
+        this.setCaretOffset(lineStartOffset + lines[lineIndex].length);
+        break;
+
+      case 'gg':
+        this.keyBuffer = '';
+        this.setCaretOffset(0);
+        break;
+
+      case 'G':
+        this.keyBuffer = '';
+        this.setCaretOffset(this.editor.innerText.length);
+        break;
+
+      case 'h':
+      case 'ArrowLeft':
+        this.keyBuffer = '';
+        const currentOffset = this.getCaretOffset();
+        if (currentOffset > 0) {
+          this.setCaretOffset(currentOffset - 1);
+        }
+        break;
+
+      case 'l':
+      case 'ArrowRight':
+        this.keyBuffer = '';
+        this.setCaretOffset(this.getCaretOffset() + 1);
+        break;
+
+      case 'j':
+      case 'ArrowDown':
+        this.keyBuffer = '';
+        if (lineIndex < lines.length - 1) {
+          const nextLineStart = lineStartOffset + lines[lineIndex].length + 1;
+          const nextLineLength = lines[lineIndex + 1].length;
+          const newPosition = Math.min(positionInLine, nextLineLength);
+          this.setCaretOffset(nextLineStart + newPosition);
+        }
+        break;
+
+      case 'k':
+      case 'ArrowUp':
+        this.keyBuffer = '';
+        if (lineIndex > 0) {
+          let prevLineStart = 0;
+          for (let i = 0; i < lineIndex - 1; i++) {
+            prevLineStart += lines[i].length + 1;
+          }
+          const prevLineLength = lines[lineIndex - 1].length;
+          const newPosition = Math.min(positionInLine, prevLineLength);
+          this.setCaretOffset(prevLineStart + newPosition);
+        }
+        break;
+
+      default:
+        // Clear buffer if it gets too long or contains invalid sequences
+        if (this.keyBuffer.length > 2 || 
+            (this.keyBuffer.length === 2 && !['dd', 'yy', 'gg'].includes(this.keyBuffer))) {
+          this.keyBuffer = '';
+        }
+        break;
+    }
+  }
+}
+
+customElements.define('njet-editor', NjetEditor);
+export { NjetEditor }