editor replaced (jprompt) multimodal tools added

jcode.py

@@ -11,12 +11,13 @@ import re
 import subprocess
 import sys
 import time
+import ssl
 import urllib.request
 
 try:
-    from prompt_toolkit import prompt
+    from jprompt import prompt  # own multiline editor (jprompt.py next to jcode.py)
 except ImportError:
-    print("ERROR: 'prompt_toolkit' not installed. Run: pip install prompt_toolkit",
+    print("ERROR: 'jprompt.py' not found - it must be in the same directory as jcode.py.",
           file=sys.stderr)
     sys.exit(1)
 from html.parser import HTMLParser
@@ -26,8 +27,9 @@ from openai import OpenAI
 
 # --------------------------------------------------------------- Configuration
 APP_NAME = "jcode"
-APP_VERSION = "0.9.3"
+APP_VERSION = "0.10.0"
-MODEL = "qwen3.6-35b-a3b-uncensored-hauhaucs-aggressive"
+DEFAULT_MODEL = "qwen3.6-35b-a3b-uncensored-hauhaucs-aggressive"
+MODEL = DEFAULT_MODEL
 
 _LM_STUDIO_URL = "http://localhost:1234/v1"
 _OLLAMA_URL    = "http://localhost:11434/v1"
@@ -40,6 +42,19 @@ def _fetch_models(url: str) -> list[str] | None:
     except Exception:
         return None
 
+def _pick_model(models: list[str]) -> str:
+    """Prefers DEFAULT_MODEL (exact, then case-insensitive, then partial match, e.g.
+    'publisher/<name>' or '<name>@q4_k_m'); falls back to the first available model."""
+    if not models: return DEFAULT_MODEL
+    want = DEFAULT_MODEL.lower()
+    for match in (lambda m: m == DEFAULT_MODEL,
+                  lambda m: m.lower() == want,
+                  lambda m: m.lower().split("/")[-1].split("@")[0] == want,
+                  lambda m: want in m.lower()):
+        for m in models:
+            if match(m): return m
+    return models[0]
+
 SETTINGS_FILE = Path("settings.json")
 def _load_settings() -> dict:
     """Reads settings.json: providers (OpenAI/Anthropic/Gemini via OpenAI-compatible endpoints) for '/backend <name>'."""
@@ -56,8 +71,7 @@ def _detect_backend() -> tuple[str, str, str]:
                             (_OLLAMA_URL,    "ollama",    "Ollama")]:
         models = _fetch_models(url)
         if models is not None:
-            if models and MODEL not in models:
+            MODEL = _pick_model(models)
-                MODEL = models[0]
             return url, key, name
     return _LM_STUDIO_URL, "lm-studio", "LM Studio"
 
@@ -76,19 +90,20 @@ def _switch_backend(name: str) -> None:
     key, bname = ("ollama", "Ollama") if url == _OLLAMA_URL else ("lm-studio", "LM Studio")
     models = _fetch_models(url)
     if models is None: print(f"{RED}\u2717 {bname} not reachable.{RESET}"); return
-    if models and MODEL not in models: MODEL = models[0]
+    MODEL = _pick_model(models)
     BASE_URL, _API_KEY, BACKEND = url, key, bname
     client = OpenAI(base_url=BASE_URL, api_key=_API_KEY, timeout=REQUEST_TIMEOUT, max_retries=0)
     print(f"{DIM}Backend: {BACKEND} ({BASE_URL}) | Model: {MODEL}{RESET}")
 
 SANDBOX = Path("code").resolve()
-MAX_STEPS = 40
+MAX_STEPS = 200
 CMD_TIMEOUT = 60  # seconds per command (compiling C/C++/Java takes time)
 CONTEXT_LIMIT = 256_000       # context window of the model (tokens)
 COMPACT_THRESHOLD = 250_000   # history is compacted from here on
 KEEP_RECENT = 8               # most recent messages kept uncompressed
-REQUEST_TIMEOUT = 600         # seconds per LLM request (local models are slow)
+REQUEST_TIMEOUT = 11600         # seconds per LLM request (local models are slow)
 RETRY_WAITS = (5, 15, 30, 60)  # wait times between retry attempts
+REASONING_EFFORT = None  # None = backend default; else "high"|"medium"|"low"|"max"|"none" (Ollama /v1)
 LOG_FILE = Path("logFile.md")
 _REQ_NR = 0  # running number of LM Studio requests
 
@@ -127,7 +142,10 @@ SYSTEM_PROMPT = (
     "You are a precise coding agent. Your working directory is already the "
     "project directory. ALWAYS give paths relative to it, e.g. 'fib.py' or "
     "'tests/test_fib.py' - NEVER with a leading 'code/' and NEVER absolute. "
-    "Use the tools to read, write, list, and edit files and to run commands.\n\n"
+    "Use the tools to read, write, list, and edit files and to run commands. "
+    "Images (view_image), screenshots (take_screenshot) and PDF pages "
+    "(view_pdf_page) are delivered as an image in the message right after the "
+    "tool result - describe only what you actually see, never guess.\n\n"
     "Language: reply in the same language as the task (German task -> German answers, English task -> English).\n\n"
     "How to work:\n"
     "1. Locate code with search_files and read a file before you edit it. "
@@ -443,6 +461,21 @@ class _TextExtractor(HTMLParser):
                 blank = True
         return "\n".join(out).strip()
 
+def _make_ssl_context() -> ssl.SSLContext:
+    """CA bundle for https fetches: certifi (pip install certifi) if available,
+    otherwise the OS/Python default. JCODE_INSECURE_SSL=1 disables verification
+    (e.g. behind a corporate proxy that re-signs TLS) - use with care."""
+    if os.environ.get("JCODE_INSECURE_SSL") == "1":
+        ctx = ssl.create_default_context()
+        ctx.check_hostname = False; ctx.verify_mode = ssl.CERT_NONE
+        return ctx
+    try:
+        import certifi  # noqa: PLC0415
+        return ssl.create_default_context(cafile=certifi.where())
+    except Exception:  # noqa: BLE001
+        return ssl.create_default_context()
+_SSL_CONTEXT = _make_ssl_context()
+
 def fetch_url(url: str, max_chars: int = 6000) -> str:
     """Loads a web page and returns the extracted text content."""
     if not url.lower().startswith(("http://", "https://")):
@@ -452,7 +485,7 @@ def fetch_url(url: str, max_chars: int = 6000) -> str:
         url, headers={"User-Agent": f"Mozilla/5.0 ({APP_NAME}/{APP_VERSION})"}
     )
     try:
-        with urllib.request.urlopen(req, timeout=15) as resp:
+        with urllib.request.urlopen(req, timeout=15, context=_SSL_CONTEXT) as resp:
             ctype = resp.headers.get("Content-Type", "")
             raw = resp.read(2_000_000)  # load at most 2 MB
             charset = resp.headers.get_content_charset() or "utf-8"
@@ -474,6 +507,128 @@ def fetch_url(url: str, max_chars: int = 6000) -> str:
         text = text[:max_chars] + f"\n...[truncated, {len(text)} characters total]..."
     return f"Content of {url}:\n{text}"
 
+# ----------------------------------------------------------------- Image tools
+# Tool results in the OpenAI chat format are text-only. Images are therefore
+# queued here and delivered to the model as a separate user message directly
+# after the tool results of the current step (works with LM Studio/Ollama for
+# vision models such as Qwen3-VL and Gemma).
+MAX_IMAGE_SIDE = 1280       # longest edge in pixels sent to the model
+MAX_IMAGES_IN_CONTEXT = 4   # older images are replaced by a text stub
+IMAGE_TOKENS = 1000         # rough token estimate per image
+_PENDING_IMAGES: list[tuple[str, str]] = []  # (label, data URI)
+
+def _pil():
+    try:
+        from PIL import Image
+        return Image
+    except ImportError:
+        raise RuntimeError("package 'Pillow' not installed - run 'pip install Pillow' with run_command")
+
+def _attach_image(img, label: str) -> str:
+    """Scales a PIL image, encodes it as data URI and queues it for the next message."""
+    import base64, io
+    w, h = img.size
+    if (scale := MAX_IMAGE_SIDE / max(w, h)) < 1:
+        img = img.resize((round(w * scale), round(h * scale)), _pil().LANCZOS)
+    buf = io.BytesIO()
+    if img.mode in ("RGBA", "LA") or "transparency" in img.info:
+        img.convert("RGBA").save(buf, "PNG"); mime = "image/png"
+    else:
+        img.convert("RGB").save(buf, "JPEG", quality=90); mime = "image/jpeg"
+    uri = f"data:{mime};base64,{base64.b64encode(buf.getvalue()).decode()}"
+    _PENDING_IMAGES.append((label, uri))
+    return f"{label} ({w}x{h}px) attached - it follows in the next message."
+
+def view_image(path: str) -> str:
+    """Loads an image file from the sandbox (png/jpg/gif/webp/bmp/svg) for visual analysis."""
+    p = _resolve(path)
+    if not p.is_file():
+        return f"File '{path}' not found. Use list_files() to see available files."
+    Image = _pil()
+    if p.suffix.lower() == ".svg":
+        try:
+            import cairosvg  # pip install cairosvg
+        except ImportError:
+            return ("ERROR: package 'cairosvg' not installed - run 'pip install cairosvg' "
+                    "with run_command (or read the SVG source with read_file).")
+        import io
+        img = Image.open(io.BytesIO(cairosvg.svg2png(url=str(p), output_width=MAX_IMAGE_SIDE)))
+    else:
+        img = Image.open(p)
+    img.load()
+    return _attach_image(img, f"Image '{path}'")
+
+def take_screenshot(save_as: str = "", delay: int = 0) -> str:
+    """Captures the whole screen (e.g. of a running GUI program) for visual analysis."""
+    Image = _pil()
+    time.sleep(max(0, min(int(delay), 30)))
+    try:
+        from PIL import ImageGrab
+        img = ImageGrab.grab()
+    except Exception as e:  # noqa: BLE001 - e.g. Wayland: use a system screenshot tool
+        import shutil, tempfile
+        tool = next((c for c in (["grim"], ["gnome-screenshot", "-f"], ["spectacle", "-bno"])
+                     if shutil.which(c[0])), None)
+        if tool is None:
+            return f"ERROR: screenshot failed ({e}) and no grim/gnome-screenshot/spectacle found."
+        tmp = Path(tempfile.mkdtemp()) / "shot.png"
+        subprocess.run(tool + [str(tmp)], capture_output=True, timeout=20)
+        if not tmp.is_file():
+            return f"ERROR: screenshot via {tool[0]} failed."
+        img = Image.open(tmp); img.load()
+    label = "Screenshot"
+    if save_as:
+        p = _resolve(save_as if Path(save_as).suffix else save_as + ".png")
+        p.parent.mkdir(parents=True, exist_ok=True)
+        img.save(p); label += f" (saved as '{p.relative_to(SANDBOX)}')"
+    return _attach_image(img, label)
+
+def view_pdf_page(path: str, page: int = 1, dpi: int = 110) -> str:
+    """Renders one page of a PDF from the sandbox as an image for visual analysis."""
+    p = _resolve(path)
+    if not p.is_file():
+        return f"File '{path}' not found. Use list_files() to see available files."
+    try:
+        try:
+            import pymupdf as fitz
+        except ImportError:
+            import fitz  # older pymupdf versions
+    except ImportError:
+        return "ERROR: package 'pymupdf' not installed - run 'pip install pymupdf' with run_command."
+    Image = _pil()
+    with fitz.open(p) as doc:
+        n = doc.page_count
+        if not 1 <= page <= n:
+            return f"page={page} invalid - '{path}' has {n} page(s)."
+        pix = doc[page - 1].get_pixmap(dpi=max(50, min(int(dpi), 200)))
+        img = Image.frombytes("RGB", (pix.width, pix.height), pix.samples)
+    return _attach_image(img, f"Page {page}/{n} of '{path}'")
+
+def _image_message() -> dict:
+    """Builds the user message carrying the queued images and clears the queue."""
+    labels = ", ".join(l for l, _ in _PENDING_IMAGES)
+    content = [{"type": "text", "text": f"[Attached from the tool result(s) above: {labels}]"}]
+    content += [{"type": "image_url", "image_url": {"url": uri}} for _, uri in _PENDING_IMAGES]
+    _PENDING_IMAGES.clear()
+    _log("### Images attached", labels)
+    return {"role": "user", "content": content}
+
+def _prune_images(messages: list) -> None:
+    """Keeps only the MAX_IMAGES_IN_CONTEXT newest images; older ones become text stubs."""
+    seen = 0
+    for msg in reversed(messages):
+        for part in reversed(msg["content"]) if isinstance(msg.get("content"), list) else ():
+            if part.get("type") == "image_url":
+                seen += 1
+                if seen > MAX_IMAGES_IN_CONTEXT:
+                    part.clear(); part.update({"type": "text", "text": "[older image removed from context]"})
+
+def _content_text(content) -> str:
+    """Text view of a message content (image parts become '[image]')."""
+    if isinstance(content, list):
+        return " ".join("[image]" if p.get("type") == "image_url" else p.get("text", "") for p in content)
+    return str(content or "")
+
 TOOL_FUNCS = {
     "list_files": list_files,
     "read_file": read_file,
@@ -485,6 +640,9 @@ TOOL_FUNCS = {
     "run_command": run_command,
     "web_search": web_search,
     "fetch_url": fetch_url,
+    "view_image": view_image,
+    "take_screenshot": take_screenshot,
+    "view_pdf_page": view_pdf_page,
 }
 
 # Per-tool descriptions and parameter descriptions.  The builder below derives
@@ -575,6 +733,32 @@ _TOOL_META = {
             "max_chars": "Max. text length (500-20000), default 6000",
         },
     },
+    "view_image": {
+        "description": (
+            "Shows an image file from the project (png, jpg, gif, webp, bmp, svg) "
+            "to you for visual analysis, e.g. a generated plot, an icon or a "
+            "mockup. The image arrives in the message after the tool result."
+        ),
+        "params": {"path": "Image file, e.g. 'plot.png' or 'assets/logo.svg'"},
+    },
+    "take_screenshot": {
+        "description": (
+            "Captures the whole screen and shows it to you, e.g. to check a GUI "
+            "program you started. Start GUI programs in the background first "
+            "(Linux/macOS: 'python app.py > app.log 2>&1 &', Windows: "
+            "'start python app.py'), then take the screenshot with a delay."
+        ),
+        "params": {"save_as": "Optional file name to keep the screenshot, e.g. 'shot.png'",
+                   "delay": "Seconds to wait before capturing (0-30), default 0"},
+    },
+    "view_pdf_page": {
+        "description": (
+            "Renders ONE page of a PDF file from the project as an image and "
+            "shows it to you. The result states the total number of pages."
+        ),
+        "params": {"page": "Page number (1-based), default 1",
+                   "dpi": "Render resolution (50-200), default 110"},
+    },
 }
 
 def _build_tool_schema(fn) -> dict:
@@ -627,11 +811,12 @@ def splash_screen() -> None:
     print(f"    Sandbox   : {SANDBOX}")
     print(f"    Max steps : {MAX_STEPS}")
     print("    " + "\u2500" * 50)
-    _submit = "Esc, Enter" if sys.platform == "darwin" else "Alt+Enter"
+    print("    Describe a task: Enter submits, Ctrl+J starts a new line, Ctrl+C aborts")
-    print(f"    Describe a task (multiline, submit with {_submit}). History is kept")
+    print("    the input or a running task, Ctrl+D or Ctrl+C on an empty prompt exits.")
-    print("    across tasks. '/status' shows usage, '/new' clears the session,")
+    print("    History is kept across tasks. '/status' shows usage, '/new' clears the session,")
     print("    '/model' sets model, '/models' lists models, '/backend <name>' switches to")
-    print("    lm-studio, ollama or a settings.json provider, '/max-turns N' sets step limit.\n")
+    print("    lm-studio, ollama or a settings.json provider, '/max-turns N' sets step limit,")
+    print("    '/reasoning high|medium|low|max|none' sets thinking effort (none = off).\n")
 
 # Descriptive action label per tool call - WITHOUT code/file content.
 def _action_label(name: str, args: dict) -> str:
@@ -664,6 +849,12 @@ def _action_label(name: str, args: dict) -> str:
         return f"\U0001f50d Researching \"{args.get('query', '')}\""
     if name == "fetch_url":
         return f"\U0001f310 Loading page {args.get('url', '')}"
+    if name == "view_image":
+        return f"\U0001f5bc\ufe0f  Viewing    {target}"
+    if name == "take_screenshot":
+        return f"\U0001f4f8 Screenshot {args.get('save_as') or ''}".rstrip()
+    if name == "view_pdf_page":
+        return f"\U0001f4c4 Rendering  {target} (page {args.get('page', 1)})"
     return f"\u2699\ufe0f  {name}"
 
 # Compact result status - never output file content or code.
@@ -724,12 +915,15 @@ LAST_USAGE_TOKENS = 0  # last real usage.total_tokens value from the server
 
 def _estimate_tokens(messages: list) -> int:
     """Rough token estimate (~4 chars/token) as a fallback without usage data."""
-    chars = 0
+    chars, images = 0, 0
     for msg in messages:
-        chars += len(str(msg.get("content") or ""))
+        content = msg.get("content")
+        chars += len(_content_text(content))
+        if isinstance(content, list):
+            images += sum(1 for p in content if p.get("type") == "image_url")
         for tc in msg.get("tool_calls") or []:
             chars += len(json.dumps(tc, ensure_ascii=False))
-    return chars // 4
+    return chars // 4 + images * IMAGE_TOKENS
 
 def _compact_cut_index(messages: list) -> int:
     """Determines the index from which messages are kept.
@@ -758,7 +952,7 @@ def _compact_messages(messages: list) -> list:
     parts = []
     for msg in old:
         role = msg.get("role", "?")
-        content = str(msg.get("content") or "")
+        content = _content_text(msg.get("content"))
         if role == "tool" and len(content) > 400:
             content = content[:400] + "...[truncated]"
         calls = ", ".join(
@@ -877,7 +1071,7 @@ def run(task: str, messages: list) -> list:
 
     The history is preserved across tasks; the compaction therefore works
     session-wide automatically. Returns the updated history (compaction
-    creates a new list).
+    is done in place, so the caller's list stays the live history).
     """
     global _REQ_NR, LAST_USAGE_TOKENS
     messages.append({"role": "user", "content": task})
@@ -889,18 +1083,19 @@ def run(task: str, messages: list) -> list:
         # response, otherwise the character heuristic. Compact on overflow.
         used = max(last_total_tokens, _estimate_tokens(messages))
         if used > COMPACT_THRESHOLD:
-            messages = _compact_messages(messages)
+            messages[:] = _compact_messages(messages)
             last_total_tokens = 0
             LAST_USAGE_TOKENS = 0
 
+        _prune_images(messages)
         try:
             _REQ_NR += 1
             _log(f"### Request {_REQ_NR}",
                  f"{len(messages)} messages in context, last: "
-                 f"{str(messages[-1].get('content') or '')[:300]}")
+                 f"{_content_text(messages[-1].get('content'))[:300]}")
             resp = _chat(
-                model=MODEL, messages=messages, tools=TOOLS, temperature=0.2
+                model=MODEL, messages=messages, tools=TOOLS, temperature=0.2,
-            )
+                **({"reasoning_effort": REASONING_EFFORT} if REASONING_EFFORT else {}))
         except LLMUnavailable as e:
             _log("### Error", str(e))
             print(f"\n{RED}\u2717 {e}{RESET}")
@@ -949,13 +1144,24 @@ def run(task: str, messages: list) -> list:
             messages.append(
                 {"role": "tool", "tool_call_id": tc.id, "content": str(result)}
             )
+        if _PENDING_IMAGES:
+            messages.append(_image_message())
         print("\u2514\u2500")
 
     print("Maximum number of steps reached.")
     return messages
 
+def _discard_incomplete(messages: list) -> None:
+    """After Ctrl+C: drops a trailing tool-call round whose tool results are incomplete."""
+    i = len(messages)
+    while i > 0 and messages[i - 1].get("role") == "tool":
+        i -= 1
+    if i > 0 and messages[i - 1].get("role") == "assistant" and messages[i - 1].get("tool_calls"):
+        if len(messages) - i < len(messages[i - 1]["tool_calls"]):
+            del messages[i - 1:]
+
 def main() -> None:
-    global LAST_USAGE_TOKENS, MODEL, MAX_STEPS
+    global LAST_USAGE_TOKENS, MODEL, MAX_STEPS, REASONING_EFFORT
     SANDBOX.mkdir(exist_ok=True)
     if (d := SETTINGS.get("default_provider")): _switch_backend(d)
     if len(sys.argv) > 1:
@@ -967,9 +1173,12 @@ def main() -> None:
         session = new_session()
         while True:
             try:
-                task = prompt("\nTask> ", multiline=True).strip()
+                task = prompt("\nTask>").strip()
-            except (EOFError, KeyboardInterrupt):
+            except (EOFError, KeyboardInterrupt) as e:
-                print("\nSee you soon.")
+                if getattr(e, "text", "").strip():   # Ctrl+C with text: discard it only
+                    print(f"{DIM}(input discarded){RESET}")
+                    continue
+                print("See you soon.")               # Ctrl+D, or Ctrl+C on an empty prompt
                 break
             if not task:
                 continue
@@ -987,9 +1196,15 @@ def main() -> None:
                 _switch_backend(task[8:].strip()); continue
             if task.lower().startswith("/model"):
                 MODEL = task[6:].strip() or MODEL; print(f"{DIM}Current model: {MODEL}{RESET}"); continue
+            if task.lower().startswith("/reasoning"):
+                r = task[10:].strip().lower(); REASONING_EFFORT = r if r in ("high", "medium", "low", "max", "none") else (None if r in ("", "default") else REASONING_EFFORT); print(f"{DIM}Reasoning effort: {REASONING_EFFORT or 'default'}{RESET}" if r in ("high", "medium", "low", "max", "none", "", "default") else f"{RED}\u2717 Use: /reasoning high|medium|low|max|none{RESET}"); continue
             if task.lower().startswith("/max-turns"):
                 MAX_STEPS = int(n) if (n := task[10:].strip()).isdigit() else MAX_STEPS; print(f"{DIM}Max steps: {MAX_STEPS}{RESET}"); continue
+            try:
                 session = run(task, session)
+            except KeyboardInterrupt:
+                _discard_incomplete(session)
+                print(f"\n{RED}\u2717 Task aborted (Ctrl+C) - the session is preserved.{RESET}")
 
 if __name__ == "__main__":
     main()

jprompt.py

@@ -0,0 +1,643 @@
+#!/usr/bin/env python3
+# MIT License - Copyright (c) 2026 Prof. Dr. Joern Fischer (full text: see README.md)
+"""jprompt - a small, dependency-free multiline prompt editor for the terminal.
+
+The editor mimics the input box of Claude Code: the text starts on its own
+line (below an optional header such as "Task>"), wraps at the terminal
+width, scrolls vertically when it is taller than the terminal and keeps the
+cursor visible at all times.  The terminal is read character by character
+(cbreak-like raw mode); nothing is echoed by the terminal itself.
+
+Keys
+    Enter            submit the text
+    Ctrl+J           insert a new line (Shift+Enter / Alt+Enter work too
+                     where the terminal reports them)
+    Ctrl+C           abort the input        -> raises Abort (a KeyboardInterrupt
+                     whose .text holds the discarded input, "" if it was empty)
+    Ctrl+D           exit the application   -> raises EOFError
+    Ctrl+V / Cmd+V   paste.  Terminals normally deliver a paste themselves
+                     (bracketed paste is enabled so newlines in the pasted
+                     text do NOT submit).  If the terminal passes Ctrl+V
+                     through, the system clipboard is read as a fallback.
+    Arrows           move the cursor.  Up on the first row and Down on the
+                     last row do nothing.
+    Home/End, Ctrl+A/Ctrl+E, Backspace, Delete, Tab (= 4 spaces)
+
+Usage
+    from jprompt import prompt
+    text = prompt("Task>")          # header is printed, editing starts below
+
+Architecture (every part can be tested without a terminal)
+    Buffer     lines + cursor and all editing operations
+    Layout     wraps the Buffer lines to a width, maps cursor <-> screen cell
+    Editor     Buffer + Layout + rendering (ANSI) into any file-like object
+    KeyReader  turns raw characters into KeyEvents (escape sequences, paste)
+    prompt()   wires everything to the real terminal (raw mode, SIGWINCH)
+
+Known limitation: terminals that *reflow* old text on resize (iTerm2,
+kitty, Windows Terminal) may leave a stale copy of the editor above the
+freshly drawn one after a resize; the editor itself and its cursor stay
+correct because every redraw is relative to the cursor position.
+"""
+from __future__ import annotations
+
+import codecs
+import os
+import select
+import shutil
+import signal
+import subprocess
+import sys
+import unicodedata
+from dataclasses import dataclass
+
+try:
+    import termios
+except ImportError:  # Windows
+    termios = None
+try:
+    import msvcrt
+except ImportError:
+    msvcrt = None
+
+__all__ = ["prompt", "Abort", "Buffer", "Layout", "Editor", "KeyReader", "KeyEvent", "RESIZE"]
+
+class Abort(KeyboardInterrupt):
+    """Raised on Ctrl+C; `.text` is the input that was being edited."""
+
+    def __init__(self, text: str = "") -> None:
+        super().__init__("input aborted")
+        self.text = text
+
+# ------------------------------------------------------------- Text helpers
+def char_width(ch: str) -> int:
+    """Display width of one character (0 for combining marks, 2 for CJK)."""
+    if unicodedata.combining(ch) or unicodedata.category(ch) in ("Mn", "Me", "Cf"):
+        return 0
+    return 2 if unicodedata.east_asian_width(ch) in ("W", "F") else 1
+
+def str_width(s: str) -> int:
+    return sum(char_width(ch) for ch in s)
+
+def _clean(text: str) -> str:
+    """Normalises newlines, expands tabs and drops control characters."""
+    text = text.replace("\r\n", "\n").replace("\r", "\n").replace("\t", "    ")
+    return "".join(ch for ch in text if ch == "\n" or unicodedata.category(ch) != "Cc")
+
+# ------------------------------------------------------------------- Buffer
+class Buffer:
+    """Editable text: a list of logical lines plus a cursor (row, col)."""
+
+    def __init__(self, text: str = "") -> None:
+        self.lines: list[str] = _clean(text).split("\n")
+        self.row = len(self.lines) - 1
+        self.col = len(self.lines[-1])
+
+    # -- state
+    @property
+    def text(self) -> str:
+        return "\n".join(self.lines)
+
+    @property
+    def cursor(self) -> tuple[int, int]:
+        return self.row, self.col
+
+    # -- editing
+    def insert(self, text: str) -> None:
+        parts = _clean(text).split("\n")
+        line = self.lines[self.row]
+        head, tail = line[: self.col], line[self.col :]
+        if len(parts) == 1:
+            self.lines[self.row] = head + parts[0] + tail
+            self.col += len(parts[0])
+            return
+        self.lines[self.row : self.row + 1] = [head + parts[0], *parts[1:-1], parts[-1] + tail]
+        self.row += len(parts) - 1
+        self.col = len(parts[-1])
+
+    def backspace(self) -> None:
+        if self.col > 0:
+            line = self.lines[self.row]
+            self.lines[self.row] = line[: self.col - 1] + line[self.col :]
+            self.col -= 1
+        elif self.row > 0:
+            self.col = len(self.lines[self.row - 1])
+            self.lines[self.row - 1] += self.lines.pop(self.row)
+            self.row -= 1
+
+    def delete(self) -> None:
+        line = self.lines[self.row]
+        if self.col < len(line):
+            self.lines[self.row] = line[: self.col] + line[self.col + 1 :]
+        elif self.row + 1 < len(self.lines):
+            self.lines[self.row] += self.lines.pop(self.row + 1)
+
+    # -- horizontal movement
+    def left(self) -> None:
+        if self.col > 0:
+            self.col -= 1
+        elif self.row > 0:
+            self.row -= 1
+            self.col = len(self.lines[self.row])
+
+    def right(self) -> None:
+        if self.col < len(self.lines[self.row]):
+            self.col += 1
+        elif self.row + 1 < len(self.lines):
+            self.row += 1
+            self.col = 0
+
+    def home(self) -> None:
+        self.col = 0
+
+    def end(self) -> None:
+        self.col = len(self.lines[self.row])
+
+# ------------------------------------------------------------------- Layout
+@dataclass(frozen=True)
+class VisualRow:
+    line: int    # index of the logical line
+    start: int   # first character (inclusive)
+    end: int     # last character (exclusive)
+    last: bool   # last visual row of its logical line?
+
+class Layout:
+    """Wraps logical lines to `width` display columns.
+
+    A logical line of exactly `width` columns is NOT split: the cursor may sit
+    at display column `width` (which is why Editor uses terminal width - 1).
+    A cursor at the end of a non-last visual row is shown at the start of the
+    next row - the same convention prompt_toolkit uses.
+    """
+
+    def __init__(self, lines: list[str], width: int) -> None:
+        self.lines = lines
+        self.width = max(1, width)
+        self.rows: list[VisualRow] = []
+        for li, line in enumerate(lines):
+            start = acc = 0
+            for i, ch in enumerate(line):
+                w = char_width(ch)
+                if acc + w > self.width and i > start:
+                    self.rows.append(VisualRow(li, start, i, False))
+                    start, acc = i, 0
+                acc += w
+            self.rows.append(VisualRow(li, start, len(line), True))
+
+    def row_text(self, r: VisualRow) -> str:
+        return self.lines[r.line][r.start : r.end]
+
+    def cursor_to_visual(self, row: int, col: int) -> tuple[int, int]:
+        """(logical row, col) -> (visual row index, display column)."""
+        for vr, r in enumerate(self.rows):
+            if r.line == row and (r.start <= col < r.end or (r.last and col == r.end)):
+                return vr, str_width(self.lines[row][r.start : col])
+        return len(self.rows) - 1, 0  # unreachable for a consistent buffer
+
+    def visual_to_cursor(self, vr: int, want_col: int) -> tuple[int, int]:
+        """(visual row index, wanted display column) -> nearest (row, col)."""
+        r = self.rows[vr]
+        line = self.lines[r.line]
+        limit = r.end if r.last else r.end - 1  # end of a wrapped row belongs to the next row
+        col, acc = r.start, 0
+        while col < limit:
+            w = char_width(line[col])
+            if acc + w > want_col:
+                break
+            acc, col = acc + w, col + 1
+        return r.line, col
+
+# ---------------------------------------------------------------- KeyEvents
+@dataclass(frozen=True)
+class KeyEvent:
+    kind: str        # text, newline, enter, backspace, delete, left, right, up,
+                     # down, home, end, ctrl_c, ctrl_d, resize, ignore
+    text: str = ""   # only for kind == "text" (typed char or pasted block)
+
+RESIZE = object()  # sentinel a key source returns when the window was resized
+
+# ------------------------------------------------------------------- Editor
+class Editor:
+    """Buffer + rendering.  `out` needs write()/flush(); `size()` -> (cols, rows).
+
+    The editor assumes the terminal cursor is at column 0 of the line where
+    the text should start when render() is first called.  All later drawing is
+    relative to the cursor, so scrolling of the terminal does not matter.
+    """
+
+    def __init__(self, out, size, text: str = "") -> None:
+        self.buf = Buffer(text)
+        self.out = out
+        self._size = size
+        self._want_col: int | None = None  # sticky column for Up/Down
+        self._top = 0        # first visible visual row (vertical scrolling)
+        self._cur_row = 0    # screen row of the cursor relative to the first drawn row
+        self._drawn = 0      # number of rows drawn by the last render()
+        self.hidden_above = 0  # visual rows scrolled out of view (shown as markers)
+        self.hidden_below = 0
+
+    # -- geometry
+    @property
+    def width(self) -> int:
+        """Wrap width: one less than the terminal so the cursor never touches the auto-wrap column."""
+        return max(1, self._size()[0] - 1)
+
+    @property
+    def height(self) -> int:
+        """Max. visible rows: one less than the terminal so a header line above survives."""
+        return max(1, self._size()[1] - 1)
+
+    @property
+    def text(self) -> str:
+        return self.buf.text
+
+    def layout(self) -> Layout:
+        return Layout(self.buf.lines, self.width)
+
+    # -- keys
+    def handle(self, key: KeyEvent) -> bool:
+        """Applies one key; returns True when the text was submitted."""
+        k = key.kind
+        if k == "ctrl_c":
+            raise Abort(self.text)
+        if k == "ctrl_d":
+            raise EOFError
+        if k == "enter":
+            return True
+        if k == "text":
+            self.buf.insert(key.text)
+        elif k == "newline":
+            self.buf.insert("\n")
+        elif k == "backspace":
+            self.buf.backspace()
+        elif k == "delete":
+            self.buf.delete()
+        elif k == "left":
+            self.buf.left()
+        elif k == "right":
+            self.buf.right()
+        elif k == "home":
+            self.buf.home()
+        elif k == "end":
+            self.buf.end()
+        elif k == "up":
+            self.move_up()
+        elif k == "down":
+            self.move_down()
+        if k not in ("up", "down", "ignore"):
+            self._want_col = None
+        self.render()
+        return False
+
+    def move_up(self) -> bool:
+        return self._vertical(-1)
+
+    def move_down(self) -> bool:
+        return self._vertical(+1)
+
+    def _vertical(self, delta: int) -> bool:
+        """Moves one *visual* row; returns False at the top/bottom edge."""
+        lay = self.layout()
+        vr, vc = lay.cursor_to_visual(*self.buf.cursor)
+        target = vr + delta
+        if not 0 <= target < len(lay.rows):
+            return False
+        if self._want_col is None:
+            self._want_col = vc
+        self.buf.row, self.buf.col = lay.visual_to_cursor(target, self._want_col)
+        return True
+
+    # -- drawing
+    def _viewport(self, vr: int, n: int) -> tuple[int, int, bool, bool]:
+        """Chooses the first visible row so the cursor row is on screen.
+
+        Returns (top, rows shown, marker above?, marker below?).  Each marker
+        line ("... N more lines ...") costs one row of the available height,
+        so the choice is iterated until it is stable.
+        """
+        h, top = self.height, self._top
+        above = below = False
+        for _ in range(3):
+            avail = max(1, h - above - below)
+            if vr < top:
+                top = vr
+            elif vr >= top + avail:
+                top = vr - avail + 1
+            top = max(0, min(top, n - avail))
+            if h < 3:                              # no room for markers
+                return top, avail, False, False
+            new = (top > 0, top + avail < n)
+            if new == (above, below):
+                return top, avail, above, below
+            above, below = new
+        return top, avail, above, below
+
+    def _marker(self, count: int, where: str) -> str:
+        text = f"\u2026 {count} more line{'s' if count != 1 else ''} {where} \u2026"
+        if str_width(text) > self.width:
+            arrow = "\u2191" if where == "above" else "\u2193"
+            text = f"\u2026{count}{arrow}"
+        return f"\x1b[2m{text}\x1b[0m"
+
+    def render(self) -> None:
+        lay = self.layout()
+        vr, vc = lay.cursor_to_visual(*self.buf.cursor)
+        n = len(lay.rows)
+        top, avail, above, below = self._viewport(vr, n)
+        self._top = top
+        self.hidden_above, self.hidden_below = top, max(0, n - top - avail)
+
+        lines = [lay.row_text(r) for r in lay.rows[top : top + avail]]
+        if above:
+            lines.insert(0, self._marker(self.hidden_above, "above"))
+        if below:
+            lines.append(self._marker(self.hidden_below, "below"))
+        crow = vr - top + int(above)
+
+        parts = []
+        if self._cur_row > 0:                      # back to the first drawn row
+            parts.append(f"\x1b[{self._cur_row}A")
+        parts.append("\r\x1b[J")                   # column 0, clear to end of screen
+        parts.append("\r\n".join(lines))
+        back = len(lines) - 1 - crow
+        if back > 0:
+            parts.append(f"\x1b[{back}A")
+        parts.append("\r")
+        if vc > 0:
+            parts.append(f"\x1b[{vc}C")
+        self.out.write("".join(parts))
+        self.out.flush()
+        self._cur_row, self._drawn = crow, len(lines)
+
+    def finish(self) -> None:
+        """Moves the cursor below the text and starts a fresh line."""
+        down = self._drawn - 1 - self._cur_row
+        self.out.write((f"\x1b[{down}B" if down > 0 else "") + "\r\n")
+        self.out.flush()
+
+# ---------------------------------------------------------------- KeyReader
+class KeyReader:
+    """Decodes characters from a `source` into KeyEvents.
+
+    source.read()            blocks; returns one character or RESIZE
+    source.pending(timeout)  True if a character arrives within `timeout` s
+    """
+
+    ESC_TIMEOUT = 0.05
+
+    _CTRL = {"\r": "enter", "\n": "newline", "\x7f": "backspace", "\x08": "backspace",
+             "\x03": "ctrl_c", "\x04": "ctrl_d", "\x01": "home", "\x05": "end"}
+    _CSI_FINAL = {"A": "up", "B": "down", "C": "right", "D": "left", "H": "home", "F": "end"}
+    _CSI_TILDE = {"1": "home", "7": "home", "4": "end", "8": "end", "3": "delete"}
+
+    def __init__(self, source) -> None:
+        self.source = source
+        self._resized = False
+
+    def read_key(self) -> KeyEvent:
+        if self._resized:
+            self._resized = False
+            return KeyEvent("resize")
+        ch = self.source.read()
+        if ch is RESIZE:
+            return KeyEvent("resize")
+        if ch == "\x1b":
+            return self._escape()
+        if ch == "\x16":                              # Ctrl+V passed through by the terminal
+            text = _clipboard()
+            return KeyEvent("text", text) if text else KeyEvent("ignore")
+        if ch == "\t":
+            return KeyEvent("text", "    ")
+        if ch in self._CTRL:
+            return KeyEvent(self._CTRL[ch])
+        if unicodedata.category(ch) != "Cc":
+            return KeyEvent("text", ch)
+        return KeyEvent("ignore")
+
+    def _next(self) -> str:
+        """Next character inside an escape sequence; remembers resizes for later."""
+        while True:
+            ch = self.source.read()
+            if ch is RESIZE:
+                self._resized = True
+                continue
+            return ch
+
+    def _escape(self) -> KeyEvent:
+        if not self.source.pending(self.ESC_TIMEOUT):
+            return KeyEvent("ignore")                 # a lone Esc
+        c = self._next()
+        if c in ("\r", "\n"):
+            return KeyEvent("newline")                # Alt+Enter
+        if c == "O":                                  # SS3: cursor keys in application mode
+            return KeyEvent(self._CSI_FINAL.get(self._next(), "ignore"))
+        if c != "[":
+            return KeyEvent("ignore")                 # Alt+<key>
+        seq = ""
+        while True:
+            d = self._next()
+            seq += d
+            if "\x40" <= d <= "\x7e":
+                break
+            if len(seq) > 32:
+                return KeyEvent("ignore")
+        return self._csi(seq)
+
+    def _csi(self, seq: str) -> KeyEvent:
+        final, params = seq[-1], seq[:-1]
+        if seq == "200~":                             # bracketed paste
+            return self._paste()
+        if final in self._CSI_FINAL:
+            return KeyEvent(self._CSI_FINAL[final])
+        if final == "~":
+            return KeyEvent(self._CSI_TILDE.get(params.split(";")[0], "ignore"))
+        if final == "u" and params.split(";")[0] == "13":  # kitty protocol: Shift/Ctrl+Enter
+            return KeyEvent("newline")
+        return KeyEvent("ignore")
+
+    def _paste(self) -> KeyEvent:
+        end, buf = "\x1b[201~", []
+        while True:
+            buf.append(self._next())
+            if len(buf) >= len(end) and "".join(buf[-len(end):]) == end:
+                return KeyEvent("text", "".join(buf[: -len(end)]))
+
+def _clipboard() -> str:
+    """Best-effort read of the system clipboard (fallback for a raw Ctrl+V)."""
+    for cmd in (["pbpaste"], ["wl-paste", "-n"], ["xclip", "-selection", "clipboard", "-o"],
+                ["xsel", "-b", "-o"], ["powershell", "-NoProfile", "-Command", "Get-Clipboard"]):
+        if shutil.which(cmd[0]):
+            try:
+                return subprocess.run(cmd, capture_output=True, text=True, timeout=2).stdout
+            except Exception:  # noqa: BLE001
+                continue
+    return ""
+
+# -------------------------------------------------------- Terminal plumbing
+class _TtySource:
+    """Character source for a POSIX tty; `wake_fd` (optional) signals resizes."""
+
+    def __init__(self, fd: int, wake_fd: int | None = None) -> None:
+        self.fd, self.wake = fd, wake_fd
+        self._dec = codecs.getincrementaldecoder("utf-8")(errors="replace")
+        self._buf: list[str] = []   # decoded but not yet consumed characters
+
+    def read(self):
+        fds = [self.fd] if self.wake is None else [self.fd, self.wake]
+        while not self._buf:
+            ready, _, _ = select.select(fds, [], [])
+            if self.wake in ready:
+                try:
+                    os.read(self.wake, 64)
+                except OSError:
+                    pass
+                return RESIZE
+            # Read whole chunks: a large paste must be drained quickly, the
+            # kernel's tty input queue is small (1 KB on macOS).
+            b = os.read(self.fd, 65536)
+            if not b:
+                raise EOFError
+            self._buf.extend(self._dec.decode(b))
+        return self._buf.pop(0)
+
+    def pending(self, timeout: float) -> bool:
+        if self._buf:
+            return True
+        ready, _, _ = select.select([self.fd], [], [], timeout)
+        return bool(ready)
+
+class _WinSource:
+    """Character source for the Windows console (msvcrt); special keys become CSI sequences."""
+
+    _SPECIAL = {"H": "A", "P": "B", "K": "D", "M": "C", "G": "H", "O": "F", "S": "3~"}
+
+    def __init__(self) -> None:
+        self._queue: list[str] = []
+
+    def read(self):
+        if self._queue:
+            return self._queue.pop(0)
+        ch = msvcrt.getwch()
+        if ch in ("\x00", "\xe0"):
+            code = self._SPECIAL.get(msvcrt.getwch())
+            if code is None:
+                return self.read()
+            self._queue.extend("[" + code)
+            return "\x1b"
+        return ch
+
+    def pending(self, timeout: float) -> bool:
+        return bool(self._queue) or msvcrt.kbhit()
+
+class _RawMode:
+    """Character-at-a-time input without echo; Enter stays '\\r', Ctrl+J stays '\\n'."""
+
+    def __init__(self, fd: int) -> None:
+        self.fd = fd
+
+    def __enter__(self):
+        if termios is None:
+            return self
+        self.old = termios.tcgetattr(self.fd)
+        new = termios.tcgetattr(self.fd)
+        new[0] &= ~(termios.ICRNL | termios.INLCR | termios.IXON)              # iflag
+        new[3] &= ~(termios.ECHO | termios.ICANON | termios.ISIG | termios.IEXTEN)  # lflag
+        new[6][termios.VMIN], new[6][termios.VTIME] = 1, 0
+        termios.tcsetattr(self.fd, termios.TCSANOW, new)
+        return self
+
+    def __exit__(self, *exc):
+        if termios is not None:
+            termios.tcsetattr(self.fd, termios.TCSADRAIN, self.old)
+
+class _ResizeWatcher:
+    """Turns SIGWINCH into a readable byte on `self.fd` (None when unsupported)."""
+
+    def __enter__(self):
+        self.fd = None
+        if not hasattr(signal, "SIGWINCH"):
+            return self
+        r, w = os.pipe()
+        try:
+            os.set_blocking(w, False)
+            self._old_wake = signal.set_wakeup_fd(w)
+            self._old_handler = signal.signal(signal.SIGWINCH, lambda *_: None)
+            self.fd, self._pipe = r, (r, w)
+        except (ValueError, OSError):  # e.g. not in the main thread
+            os.close(r), os.close(w)
+        return self
+
+    def __exit__(self, *exc):
+        if self.fd is None:
+            return
+        signal.signal(signal.SIGWINCH, self._old_handler)
+        signal.set_wakeup_fd(self._old_wake)
+        for fd in self._pipe:
+            os.close(fd)
+
+def _terminal_size() -> tuple[int, int]:
+    size = shutil.get_terminal_size((80, 24))
+    return size.columns, size.lines
+
+def _enable_windows_vt() -> None:
+    try:
+        import ctypes
+        k32 = ctypes.windll.kernel32
+        handle, mode = k32.GetStdHandle(-11), ctypes.c_uint32()
+        if k32.GetConsoleMode(handle, ctypes.byref(mode)):
+            k32.SetConsoleMode(handle, mode.value | 0x0004)  # ENABLE_VIRTUAL_TERMINAL_PROCESSING
+    except Exception:  # noqa: BLE001
+        pass
+
+def _interactive() -> bool:
+    try:
+        return sys.stdin.isatty() and sys.stdout.isatty() and (termios or msvcrt) is not None
+    except (AttributeError, ValueError):
+        return False
+
+# ------------------------------------------------------------------- prompt
+def prompt(header: str = "", text: str = "") -> str:
+    """Prints `header` (if any) and edits `text` on the following line(s).
+
+    Returns the entered text on Enter.  Raises Abort (a KeyboardInterrupt with
+    the current input in `.text`) on Ctrl+C and EOFError on Ctrl+D.  Without a
+    terminal (pipe), one line is read from stdin instead.
+    """
+    if header:
+        print(header, flush=True)
+    if not _interactive():
+        line = sys.stdin.readline()
+        if not line:
+            raise EOFError
+        return line.rstrip("\r\n")
+
+    out = sys.stdout
+    editor = Editor(out, _terminal_size, text)
+    if termios is None:
+        _enable_windows_vt()
+        source, fd = _WinSource(), None
+    else:
+        fd = sys.stdin.fileno()
+    with _RawMode(fd), _ResizeWatcher() as watcher:
+        if termios is not None:
+            source = _TtySource(fd, watcher.fd)
+        reader = KeyReader(source)
+        out.write("\x1b[?25h\x1b[?2004h")  # cursor visible, bracketed paste on
+        try:
+            editor.render()
+            while not editor.handle(reader.read_key()):
+                pass
+        finally:
+            editor.finish()
+            out.write("\x1b[?2004l")
+            out.flush()
+    return editor.text
+
+if __name__ == "__main__":
+    try:
+        result = prompt("jprompt demo - Enter submits, Ctrl+J = new line, Ctrl+C aborts, Ctrl+D exits\nText>")
+        print(f"You entered: {result!r}")
+    except KeyboardInterrupt:
+        print("(aborted)")
+    except EOFError:
+        print("(exit)")