command_line: add a prompt function

bebop/browser/browser.py

@@ -253,11 +253,11 @@ class Browser:
 
     def quick_command(self, command):
         """Shortcut method to take user input with a prefixed command string."""
-        prefix = f"{command} " if command else ""
+        prefix = command + " " if command else ""
-        user_input = self.command_line.focus(":", prefix=prefix)
+        text = self.command_line.focus(CommandLine.CHAR_COMMAND, prefix=prefix)
-        if not user_input:
+        if not text:
             return
-        self.process_command(user_input)
+        self.process_command(text)
 
     def process_command(self, command_text: str):
         """Handle a client command."""
@@ -480,7 +480,10 @@ class Browser:
             return
         self.set_status("Bookmark title?")
         current_title = self.page_pad.current_page.title or ""
-        title = self.command_line.focus(">", prefix=current_title)
+        title = self.command_line.focus(
+            CommandLine.CHAR_TEXT,
+            prefix=current_title
+        )
         if title:
             title = title.strip()
             if title:
@@ -525,3 +528,8 @@ class Browser:
         """Show the help page."""
         self.load_page(Page.from_gemtext(HELP_PAGE, self.config["text_width"]))
         self.current_url = "bebop://help"
+
+    def prompt(self, text, keys):
+        """Display the text and allow it to type one of the given keys."""
+        self.set_status(text)
+        return self.command_line.prompt_key(keys)

bebop/browser/gemini.py

@@ -3,6 +3,7 @@
 from pathlib import Path
 
 from bebop.browser.browser import Browser
+from bebop.command_line import CommandLine
 from bebop.fs import get_downloads_path
 from bebop.navigation import set_parameter
 from bebop.page import Page
@@ -42,7 +43,7 @@ def open_gemini_url(browser: Browser, url, redirects=0, history=True,
             error = f"Certificate has been changed ({url})."
             # TODO propose the user ways to handle this.
         elif req.state == Request.STATE_CONNECTION_FAILED:
-            error_details = f": {req.error}" if req.error else "."
+            error_details = ": " + req.error if req.error else "."
             error = f"Connection failed ({url})" + error_details
         else:
             error = f"Connection failed ({url})."
@@ -67,21 +68,27 @@ def open_gemini_url(browser: Browser, url, redirects=0, history=True,
         browser.set_status_error(f"Server response parsing failed ({url}).")
         return
 
+    _handle_response(browser, response, url, redirects, history)
+
+
+def _handle_response(browser: Browser, response: Response, url: str,
+                     redirects: int, history: bool):
+    """Handle a response from a Gemini server."""
     if response.code == 20:
-        handle_response_content(browser, url, response, history)
+        _handle_successful_response(browser, response, url, history)
     elif response.generic_code == 30 and response.meta:
         browser.open_url(response.meta, base_url=url, redirects=redirects + 1)
     elif response.generic_code in (40, 50):
         error = f"Server error: {response.meta or Response.code.name}"
         browser.set_status_error(error)
     elif response.generic_code == 10:
-        handle_input_request(browser, url, response.meta)
+        _handle_input_request(browser, url, response.meta)
     else:
         error = f"Unhandled response code {response.code}"
         browser.set_status_error(error)
 
 
-def handle_response_content(browser: Browser, url: str, response: Response,
+def _handle_successful_response(browser: Browser, response: Response, url: str,
                                 history: bool):
     """Handle a successful response content from a Gemini server.
 
@@ -116,7 +123,7 @@ def handle_response_content(browser: Browser, url: str, response: Response,
             text = response.content.decode("utf-8", errors="replace")
             page = Page.from_text(text)
     else:
-        filepath = get_download_path(url)
+        filepath = _get_download_path(url)
 
     if page:
         browser.load_page(page)
@@ -137,7 +144,7 @@ def handle_response_content(browser: Browser, url: str, response: Response,
         browser.set_status_error(error)
 
 
-def get_download_path(url: str) -> Path:
+def _get_download_path(url: str) -> Path:
     """Try to find the best download file path possible from this URL."""
     download_dir = get_downloads_path()
     url_parts = url.rsplit("/", maxsplit=1)
@@ -149,13 +156,13 @@ def get_download_path(url: str) -> Path:
     return download_dir / filename
 
 
-def handle_input_request(browser: Browser, from_url: str, message: str =None):
+def _handle_input_request(browser: Browser, from_url: str, message: str =None):
     """Focus command-line to pass input to the server."""
     if message:
         browser.set_status(f"Input needed: {message}")
     else:
         browser.set_status("Input needed:")
-    user_input = browser.command_line.focus("?")
+    user_input = browser.command_line.focus(CommandLine.CHAR_TEXT)
     if not user_input:
         return
     url = set_parameter(from_url, user_input)

bebop/command_line.py

@@ -17,18 +17,35 @@ class CommandLine:
     the window's right border when writing more content than the width allows.
     Therefore I just added the M-e keybind to call an external editor and use
     its content as result.
+
+    Attributes:
+    - window: curses window to use for the command line and Textbox.
+    - editor_command: external command to use to edit content externally.
+    - textbox: Textbox object handling user input.
     """
 
+    CHAR_COMMAND = ":"
+    CHAR_DIGIT = "&"
+    CHAR_TEXT = ">"
+
     def __init__(self, window, editor_command):
         self.window = window
         self.editor_command = editor_command
-        self.textbox = None
+        self.textbox = curses.textpad.Textbox(self.window)
 
     def clear(self):
         """Clear command-line contents."""
         self.window.clear()
         self.window.refresh()
 
+    def gather(self):
+        """Return the string currently written by the user in command line.
+
+        This doesn't count the command char used, but it includes then prefix.
+        Trailing whitespace is trimmed.
+        """
+        return self.textbox.gather()[1:].rstrip()
+
     def focus(self, command_char, validator=None, prefix=""):
         """Give user focus to the command bar.
 
@@ -46,13 +63,13 @@ class CommandLine:
         User input as string. The string will be empty if the validator raised
         an EscapeInterrupt.
         """
+        validator = validator or self._validate_common_input
         self.window.clear()
         self.window.refresh()
-        self.textbox = curses.textpad.Textbox(self.window)
         self.window.addstr(command_char + prefix)
         curses.curs_set(1)
         try:
-            command = self.textbox.edit(validator or self.validate_common_input)
+            command = self.textbox.edit(validator)
         except EscapeCommandInterrupt:
             command = ""
         except TerminateCommandInterrupt as exc:
@@ -63,11 +80,7 @@ class CommandLine:
         self.clear()
         return command
 
-    def gather(self):
+    def _validate_common_input(self, ch: int):
-        """Return the string currently written by the user in command line."""
-        return self.textbox.gather()[1:].rstrip()
-
-    def validate_common_input(self, ch: int):
         """Generic input validator, handles a few more cases than default.
 
         This validator can be used as a default validator as it handles, on top
@@ -136,8 +149,8 @@ class CommandLine:
         if len(candidates) == 1:
             return 0, candidates[0]
         # Else, focus the command line to let the user input more digits.
-        validator = lambda ch: self.validate_link_digit(ch, links, max_digits)
+        validator = lambda ch: self._validate_link_digit(ch, links, max_digits)
-        link_input = self.focus("&", validator, digit)
+        link_input = self.focus(CommandLine.CHAR_DIGIT, validator, digit)
         if not link_input:
             return 1, None
         try:
@@ -146,10 +159,10 @@ class CommandLine:
             return 2, f"Invalid link ID {link_input}."
         return 0, link_id
 
-    def validate_link_digit(self, ch: int, links: Links, max_digits: int):
+    def _validate_link_digit(self, ch: int, links: Links, max_digits: int):
         """Handle input chars to be used as link ID."""
         # Handle common chars.
-        ch = self.validate_common_input(ch)
+        ch = self._validate_common_input(ch)
         # Only accept digits. If we reach the amount of required digits, open
         # link now and leave command line. Else just process it.
         if curses.ascii.isdigit(ch):
@@ -185,6 +198,21 @@ class CommandLine:
             return
         raise TerminateCommandInterrupt(content)
 
+    def prompt_key(self, keys):
+        """Focus the command line and wait for the user """
+        validator = lambda ch: self._validate_prompt(ch, keys)
+        key = self.focus(CommandLine.CHAR_TEXT, validator)
+        return key if key in keys else ""
+
+    def _validate_prompt(self, ch: int, keys):
+        """Handle input chars and raise a terminate interrupt on a valid key."""
+        # Handle common keys.
+        ch = self._validate_common_input(ch)
+        char = chr(ch)
+        if char in keys:
+            raise TerminateCommandInterrupt(char)
+        return 0
+
 
 class EscapeCommandInterrupt(Exception):
     """Signal that ESC has been pressed during command line."""