"""
HelpScout Summary Agent
Generates a page-level summary report from filtered HelpScout conversations.
Analyses the already-extracted SUMMARY fields to surface patterns and insights
beyond the pre-tagged topics / sentiments.
"""
import json
import sys
from pathlib import Path
from typing import Any, Dict

import pandas as pd

# Ensure visualization/ is on sys.path so agents.*, utils.* imports resolve
_parent = Path(__file__).resolve().parent.parent
if str(_parent) not in sys.path:
    sys.path.insert(0, str(_parent))

from agents.base_agent import BaseVisualizationAgent
from utils.llm_helper import LLMHelper
from utils.helpscout_utils import topic_label, load_topic_taxonomy


class HelpScoutSummaryAgent(BaseVisualizationAgent):
    """
    Produces an executive summary report from a filtered set of HelpScout
    conversations by reading their SUMMARY fields through an LLM.
    """

    MAX_SUMMARY_CHARS = 250  # per conversation summary sent to LLM

    def __init__(self, model: str = "gpt-5-nano", temperature: float = 1,
                 max_conversations: int = 300):
        super().__init__(name="HelpScoutSummaryAgent", model=model, temperature=temperature)
        self.llm_helper = LLMHelper(model=model, temperature=temperature)
        self.max_conversations = max_conversations
        self.taxonomy = load_topic_taxonomy()

    # ─────────────────────────────────────────────────────────────
    # BaseVisualizationAgent interface
    # ─────────────────────────────────────────────────────────────

    def validate_input(self, input_data: Dict[str, Any]) -> bool:
        if "conversations" not in input_data:
            self.log_processing("Missing 'conversations' key", level="error")
            return False
        if not isinstance(input_data["conversations"], pd.DataFrame):
            self.log_processing("'conversations' must be a DataFrame", level="error")
            return False
        if "summary" not in input_data["conversations"].columns:
            self.log_processing("DataFrame must contain a 'summary' column", level="error")
            return False
        return True

    def process(self, input_data: Dict[str, Any]) -> Dict[str, Any]:
        """
        Generate an aggregate summary report from filtered HelpScout conversations.

        Args:
            input_data: {
                'conversations':      pd.DataFrame  (must have 'summary' column),
                'filter_description': str           (human-readable applied filters),
                'max_conversations':  int           (optional; overrides instance default),
            }

        Returns:
            {
                'success': bool,
                'summary': {
                    'executive_summary':    str,
                    'top_themes':           [{'theme': str, 'description': str, 'prevalence': str}],
                    'top_complaints':       [str],
                    'unexpected_insights':  [str],
                    'recommended_actions':  [{'priority': str, 'action': str, 'rationale': str}],
                    'notable_quotes':       [str],
                },
                'metadata': {
                    'total_conversations_analyzed': int,
                    'model_used':   str,
                    'tokens_used':  int,
                    'filter_applied': str,
                },
                'error': str | None,
            }
        """
        try:
            if not self.validate_input(input_data):
                return {"success": False, "error": "Invalid input data", "summary": None}

            df = input_data["conversations"]
            filter_desc = input_data.get("filter_description", "No filters applied")
            max_convs = input_data.get("max_conversations", self.max_conversations)

            total_available = len(df)

            if total_available == 0:
                return self._empty_result(filter_desc)

            # Sample if over cap — stratified by sentiment to preserve signal
            df_sample = self._stratified_sample(df, max_convs)
            n_analyzed = len(df_sample)

            self.log_processing(
                f"Analysing {n_analyzed} of {total_available} conversations"
                f" (filter: {filter_desc[:60]})"
            )

            # Build aggregate context for the LLM
            agg_context = self._build_aggregate_context(df_sample, df)
            prompt = self._build_prompt(agg_context, filter_desc, n_analyzed)

            system_msg = (
                "You are an expert customer support analyst for Musora, "
                "a music education platform (Drumeo, Pianote, Guitareo, Singeo, PlayBass). "
                "Your role is to synthesize customer support conversation summaries "
                "and surface actionable insights that go beyond simple tagging."
            )

            response = self.llm_helper.get_structured_completion(
                prompt=prompt,
                system_message=system_msg,
                max_retries=3,
            )

            if not response["success"]:
                return self.handle_error(
                    Exception(response.get("error", "LLM call failed")),
                    context=f"filter={filter_desc[:60]}"
                )

            summary = response["content"]
            summary = self._ensure_defaults(summary)

            return {
                "success": True,
                "summary": summary,
                "metadata": {
                    "total_conversations_analyzed": n_analyzed,
                    "total_available": total_available,
                    "model_used": response["model"],
                    "tokens_used": response["usage"]["total_tokens"],
                    "filter_applied": filter_desc,
                },
                "error": None,
            }

        except Exception as e:
            return self.handle_error(e, context=input_data.get("filter_description", ""))

    # ─────────────────────────────────────────────────────────────
    # Private helpers
    # ─────────────────────────────────────────────────────────────

    def _stratified_sample(self, df: pd.DataFrame, cap: int) -> pd.DataFrame:
        """Stratified sample by sentiment to keep signal diversity."""
        if len(df) <= cap:
            return df
        try:
            strat_col = "sentiment_polarity"
            if strat_col in df.columns and df[strat_col].nunique() > 1:
                # Proportional allocation per sentiment group
                groups = df.groupby(strat_col, group_keys=False)
                sampled = groups.apply(
                    lambda g: g.sample(
                        n=max(1, int(cap * len(g) / len(df))),
                        random_state=42,
                    )
                )
                return sampled.head(cap)
        except Exception:
            pass
        return df.sample(n=cap, random_state=42)

    def _build_aggregate_context(self, df_sample: pd.DataFrame,
                                 df_full: pd.DataFrame) -> str:
        """Build a text block with aggregate stats + conversation summaries."""
        total = len(df_full)
        n_sample = len(df_sample)

        # Aggregate stats from the full filtered set
        stats = []
        if "sentiment_polarity" in df_full.columns:
            sent_counts = df_full["sentiment_polarity"].value_counts()
            sent_pct = (sent_counts / total * 100).round(1)
            stats.append("Sentiment breakdown: " +
                          ", ".join(f"{s} {pct}%" for s, pct in sent_pct.items()))

        if "topics" in df_full.columns:
            from utils.helpscout_utils import explode_topics
            exploded = explode_topics(df_full)
            if not exploded.empty:
                top_topics = exploded["topic_id"].value_counts().head(8)
                topic_strs = [f"{topic_label(t, self.taxonomy)} ({c})" for t, c in top_topics.items()]
                stats.append("Top topics: " + ", ".join(topic_strs))

        from utils.helpscout_utils import boolean_flag_counts
        flags = boolean_flag_counts(df_full)
        flag_parts = []
        if flags["is_refund_request"]:
            flag_parts.append(f"Refund requests: {flags['is_refund_request']}")
        if flags["is_cancellation"]:
            flag_parts.append(f"Cancellations: {flags['is_cancellation']}")
        if flags["is_membership"]:
            flag_parts.append(f"Membership joins: {flags['is_membership']}")
        if flag_parts:
            stats.append(", ".join(flag_parts))

        if "duration_hours" in df_full.columns:
            avg_dur = df_full["duration_hours"].mean()
            stats.append(f"Average conversation duration: {avg_dur:.1f} hours")

        stats_block = "\n".join(stats)

        # Individual summaries (capped per conversation)
        summaries = []
        for i, row in enumerate(df_sample.itertuples(), 1):
            s = getattr(row, "summary", None) or ""
            s = str(s).strip()
            if s:
                s = s[:self.MAX_SUMMARY_CHARS] + ("…" if len(s) > self.MAX_SUMMARY_CHARS else "")
                sent = getattr(row, "sentiment_polarity", "")
                summaries.append(f"[{i}] ({sent}) {s}")

        summaries_block = "\n".join(summaries) if summaries else "No summaries available."

        note = (f"Note: Showing {n_sample} of {total} matched conversations."
                if n_sample < total else f"Showing all {total} matched conversations.")

        return f"""=== AGGREGATE STATISTICS ===
{stats_block}
{note}

=== CONVERSATION SUMMARIES ===
{summaries_block}"""

    def _build_prompt(self, context: str, filter_desc: str,
                      n_analyzed: int) -> str:
        return f"""Analyze the following {n_analyzed} HelpScout customer support conversation summaries for Musora.

Applied filters: {filter_desc}

{context}

Your task: Synthesize these conversations and produce insights that go BEYOND the pre-extracted tags.
Look for underlying patterns, recurring pain points, emotional signals, product gaps, and operational issues
that would not be obvious from simple topic counts alone.

Respond in JSON with this exact structure:
{{
    "executive_summary": "3-5 sentence high-level synthesis of what customers are experiencing",
    "top_themes": [
        {{
            "theme": "Short theme name (not a topic tag)",
            "description": "What customers are actually saying and feeling about this",
            "prevalence": "Rough estimate: e.g. 'Appears in ~30% of conversations'"
        }}
    ],
    "top_complaints": [
        "Specific actionable complaint statement (not generic)"
    ],
    "unexpected_insights": [
        "A pattern, contradiction, or insight that would surprise a product manager"
    ],
    "notable_quotes": [
        "Paraphrased quote or representative statement from conversations (not verbatim)"
    ]
}}

Guidelines:
- Top themes: 5-8 items, each distinct from pre-extracted topics
- Top complaints: 5-8 bullet points, specific and actionable
- Unexpected insights: 3-5 items, must genuinely go beyond the tag taxonomy
- Notable quotes: 3-5 representative paraphrases
- If a section has fewer relevant items, use fewer — quality over quantity
"""

    @staticmethod
    def _ensure_defaults(summary: dict) -> dict:
        defaults = {
            "executive_summary": "",
            "top_themes": [],
            "top_complaints": [],
            "unexpected_insights": [],
            "notable_quotes": [],
        }
        for k, v in defaults.items():
            if k not in summary:
                summary[k] = v
        return summary

    def _empty_result(self, filter_desc: str) -> dict:
        return {
            "success": True,
            "summary": {
                "executive_summary": "No conversations matched the selected filters.",
                "top_themes": [],
                "top_complaints": [],
                "unexpected_insights": [],
                "notable_quotes": [],
            },
            "metadata": {
                "total_conversations_analyzed": 0,
                "total_available": 0,
                "model_used": self.model,
                "tokens_used": 0,
                "filter_applied": filter_desc,
            },
            "error": None,
        }