From a51f389b91397432164bdc3152f96343b8a35561 Mon Sep 17 00:00:00 2001
From: jesopo <github@lolnerd.net>
Date: Fri, 17 Apr 2020 00:05:54 +0100
Subject: [PATCH] add example factoid bot

---
 examples/factoids.py | 155 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 155 insertions(+)
 create mode 100644 examples/factoids.py

diff --git a/examples/factoids.py b/examples/factoids.py
new file mode 100644
index 0000000..4543f83
--- /dev/null
+++ b/examples/factoids.py
@@ -0,0 +1,155 @@
+import asyncio, re
+from typing    import Dict, List, Optional
+from irctokens import build, Line
+from ircrobots import Bot     as BaseBot
+from ircrobots import Server  as BaseServer
+from ircrobots import ConnectionParams
+
+TRIGGER = "!"
+
+def _delims(s: str, delim: str):
+    s_copy = list(s)
+    while s_copy:
+        char = s_copy.pop(0)
+        if char == delim:
+            if not s_copy:
+                yield len(s)-(len(s_copy)+1)
+            elif not s_copy.pop(0) == delim:
+                yield len(s)-(len(s_copy)+2)
+
+def _sed(sed: str, s: str) -> Optional[str]:
+    if len(sed) > 1:
+        delim            = sed[1]
+        last             = 0
+        parts: List[str] = []
+        for i in _delims(sed, delim):
+            parts.append(sed[last:i])
+            last = i+1
+            if len(parts) == 4:
+                break
+
+        pattern, replace, *args = parts
+        flags_s = (args or [""])[0]
+
+        flags = re.I if "i" in flags_s else 0
+        count = 0    if "g" in flags_s else 1
+
+        for i in reversed(list(_delims(replace, "&"))):
+            replace = replace[:i] + "\\g<0>" + replace[i+1:]
+
+        try:
+            compiled = re.compile(pattern, flags)
+        except:
+            return None
+        return re.sub(compiled, replace, s, count)
+    else:
+        return None
+
+class Database:
+    def __init__(self):
+        self._settings: Dict[str, str] = {}
+
+    async def get(self, context: str, setting: str) -> Optional[str]:
+        return self._settings.get(setting, None)
+    async def set(self, context: str, setting: str, value: str):
+        self._settings[setting] = value
+    async def rem(self, context: str, setting: str):
+        if setting in self._settings:
+            del self._settings[setting]
+
+class Server(BaseServer):
+    def __init__(self, name: str, database: Database):
+        super().__init__(name)
+        self._database = database
+
+    async def line_send(self, line: Line):
+        print(f"> {line.format()}")
+
+    async def line_read(self, line: Line):
+        print(f"< {line.format()}")
+
+        me = self.nickname_lower
+        if line.command == "001":
+            await self.send(build("JOIN", ["##robots"]))
+
+        if (
+                line.command == "PRIVMSG" and
+                self.has_channel(line.params[0]) and
+                not line.hostmask is None and
+                not self.casefold(line.hostmask.nickname) == me and
+                self.has_user(line.hostmask.nickname) and
+                line.params[1].startswith(TRIGGER)):
+
+            channel = self.channels[self.casefold(line.params[0])]
+            user    = self.users[self.casefold(line.hostmask.nickname)]
+            cuser   = self.channel_users[channel][user]
+            text    = line.params[1].replace(TRIGGER, "", 1)
+            db_context = f"{self.name}:{channel.name}"
+
+            name,   _, text = text.partition(" ")
+            action, _, text = text.partition(" ")
+            name = name.lower()
+            key  = f"factoid-{name}"
+
+
+            out = ""
+            if not action or action == "@":
+                value = await self._database.get(db_context, key)
+                if not value is None:
+                    out = f"({name}) {value}"
+                    if action == "@" and text:
+                        target, _, _ = text.partition(" ")
+                        out = f"{target}: {out}"
+                else:
+                    out = f"{user.nickname}: '{name}' not found"
+
+            elif action in ["==", "~="]:
+                if "o" in cuser.modes:
+                    value, _, _ = text.partition(" ")
+                    if action == "==":
+                        if value:
+                            await self._database.set(db_context, key, value)
+                            out = f"{user.nickname}: added factoid {name}"
+                        else:
+                            await self._database.rem(db_context, key)
+                            out = f"{user.nickname}: removed factoid {name}"
+                    elif action == "~=":
+                        current = await self._database.get(db_context, key)
+                        if current is None:
+                            out = f"{user.nickname}: '{name}' not found"
+                        elif value:
+                            changed = _sed(value, current)
+                            if not changed is None:
+                                await self._database.set(
+                                    db_context, key, changed)
+                                out = (f"{user.nickname}: "
+                                       f"changed '{name}' factoid")
+                            else:
+                                out = f"{user.nickname}: invalid sed"
+                        else:
+                            out = f"{user.nickname}: please provide a sed"
+                else:
+                    out = f"{user.nickname}: you are not an op"
+
+
+            else:
+                out = f"{user.nickname}: unknown action '{action}'"
+            await self.send(build("PRIVMSG", [line.params[0], out]))
+
+class Bot(BaseBot):
+    def create_server(self, name: str):
+        return Server(name, Database())
+
+async def main():
+    bot = Bot()
+
+    params = ConnectionParams(
+        "robot",
+        "chat.freenode.invalid",
+        6697,
+        tls=True)
+    await bot.add_server("freenode", params)
+    await bot.run()
+
+if __name__ == "__main__":
+    asyncio.run(main())