"""
Marker parsing for Orchestrated Discussions.

This module handles parsing of structured markers in discussion content:
- VOTE: READY|CHANGES|REJECT
- Q: / QUESTION: - Questions
- TODO: / ACTION: - Action items
- DECISION: - Decisions
- ASSIGNED: - Claimed tasks
- DONE: - Completed tasks
- CONCERN: - Raised concerns
- DIAGRAM: - Diagram references (path to .puml file)
- @alias - Mentions

See docs/DESIGN.md for full marker specification.
"""

import re
from dataclasses import dataclass
from typing import Optional


# Regex patterns for marker extraction
VOTE_PATTERN = re.compile(r'^VOTE:\s*(READY|CHANGES|REJECT)\s*$', re.IGNORECASE | re.MULTILINE)
QUESTION_PATTERN = re.compile(r'^(?:Q|QUESTION):\s*(.+)$', re.IGNORECASE | re.MULTILINE)
TODO_PATTERN = re.compile(r'^(?:TODO|ACTION):\s*(.+)$', re.IGNORECASE | re.MULTILINE)
DECISION_PATTERN = re.compile(r'^DECISION:\s*(.+)$', re.IGNORECASE | re.MULTILINE)
ASSIGNED_PATTERN = re.compile(r'^ASSIGNED:\s*(.+)$', re.IGNORECASE | re.MULTILINE)
DONE_PATTERN = re.compile(r'^DONE:\s*(.+)$', re.IGNORECASE | re.MULTILINE)
CONCERN_PATTERN = re.compile(r'^CONCERN:\s*(.+)$', re.IGNORECASE | re.MULTILINE)
DIAGRAM_PATTERN = re.compile(r'^DIAGRAM:\s*(.+)$', re.IGNORECASE | re.MULTILINE)
MENTION_PATTERN = re.compile(r'@(\w+)')


@dataclass
class Question:
    """A question raised in the discussion."""
    text: str
    author: str
    status: str = "open"  # open, answered, deferred


@dataclass
class ActionItem:
    """An action item or TODO."""
    text: str
    author: str
    assignee: Optional[str] = None
    status: str = "todo"  # todo, assigned, done


@dataclass
class Decision:
    """A decision made in the discussion."""
    text: str
    author: str
    supporters: list[str] = None

    def __post_init__(self):
        if self.supporters is None:
            self.supporters = []


@dataclass
class Concern:
    """A concern raised by a participant."""
    text: str
    author: str
    addressed: bool = False


@dataclass
class Diagram:
    """A diagram reference in the discussion."""
    path: str  # Path to the diagram file
    author: str


@dataclass
class Mention:
    """An @mention in the discussion."""
    target: str  # The alias mentioned
    author: str
    context: str  # Surrounding text


def extract_vote(text: str) -> Optional[str]:
    """
    Extract vote from text.

    Args:
        text: Text to search for vote

    Returns:
        Vote value (READY, CHANGES, REJECT) or None
    """
    match = VOTE_PATTERN.search(text)
    if match:
        return match.group(1).upper()
    return None


def extract_questions(text: str, author: str = "unknown") -> list[Question]:
    """
    Extract all questions from text.

    Args:
        text: Text to search
        author: Author to attribute questions to

    Returns:
        List of Question objects
    """
    questions = []
    for match in QUESTION_PATTERN.finditer(text):
        questions.append(Question(
            text=match.group(1).strip(),
            author=author
        ))
    return questions


def extract_action_items(text: str, author: str = "unknown") -> list[ActionItem]:
    """
    Extract all action items/TODOs from text.

    Args:
        text: Text to search
        author: Author to attribute items to

    Returns:
        List of ActionItem objects
    """
    items = []
    for match in TODO_PATTERN.finditer(text):
        item_text = match.group(1).strip()
        # Check for @mention to determine assignee
        mention = MENTION_PATTERN.search(item_text)
        assignee = mention.group(1) if mention else None

        items.append(ActionItem(
            text=item_text,
            author=author,
            assignee=assignee
        ))
    return items


def extract_decisions(text: str, author: str = "unknown") -> list[Decision]:
    """
    Extract all decisions from text.

    Args:
        text: Text to search
        author: Author to attribute decisions to

    Returns:
        List of Decision objects
    """
    decisions = []
    for match in DECISION_PATTERN.finditer(text):
        decisions.append(Decision(
            text=match.group(1).strip(),
            author=author
        ))
    return decisions


def extract_concerns(text: str, author: str = "unknown") -> list[Concern]:
    """
    Extract all concerns from text.

    Args:
        text: Text to search
        author: Author to attribute concerns to

    Returns:
        List of Concern objects
    """
    concerns = []
    for match in CONCERN_PATTERN.finditer(text):
        concerns.append(Concern(
            text=match.group(1).strip(),
            author=author
        ))
    return concerns


def extract_diagrams(text: str, author: str = "unknown") -> list[Diagram]:
    """
    Extract all diagram references from text.

    Args:
        text: Text to search
        author: Author to attribute diagrams to

    Returns:
        List of Diagram objects
    """
    diagrams = []
    for match in DIAGRAM_PATTERN.finditer(text):
        diagrams.append(Diagram(
            path=match.group(1).strip(),
            author=author
        ))
    return diagrams


def extract_mentions(text: str, author: str = "unknown") -> list[Mention]:
    """
    Extract all @mentions from text.

    Args:
        text: Text to search
        author: Author making the mentions

    Returns:
        List of Mention objects
    """
    mentions = []
    for match in MENTION_PATTERN.finditer(text):
        # Get surrounding context (the line containing the mention)
        start = text.rfind('\n', 0, match.start()) + 1
        end = text.find('\n', match.end())
        if end == -1:
            end = len(text)
        context = text[start:end].strip()

        mentions.append(Mention(
            target=match.group(1),
            author=author,
            context=context
        ))
    return mentions


def extract_all_markers(text: str, author: str = "unknown") -> dict:
    """
    Extract all markers from text.

    Args:
        text: Text to search
        author: Author to attribute markers to

    Returns:
        Dict with keys: vote, questions, action_items, decisions, concerns, mentions
    """
    return {
        "vote": extract_vote(text),
        "questions": extract_questions(text, author),
        "action_items": extract_action_items(text, author),
        "decisions": extract_decisions(text, author),
        "concerns": extract_concerns(text, author),
        "diagrams": extract_diagrams(text, author),
        "mentions": extract_mentions(text, author),
    }