from __future__ import annotations

import logging
from typing import Dict, List, TypedDict, Optional

from .data_loader import (
    load_attractions,
    load_wait_history,
    get_attraction_by_name,
)
from .models import ItineraryPlan, ItineraryStop, UserRequest
from .routing import greedy_schedule, order_by_nearest_neighbor
from .llm import generate_narrative_logs


logger = logging.getLogger("qiddiya.agents")


class QiddiyaState(TypedDict, total=False):
    user_request: Dict
    logs: List[str]
    wait_time_forecast: Dict[str, int] | None
    raw_plan: Dict | None
    final_plan: Dict | None
    critique: str | None
    reflection_round: int
    refined_attraction_ids: List[str] | None  # after reflection: only schedule these (in order)


def _append_log(state: QiddiyaState, message: str) -> None:
    logs = state.get("logs", [])
    logs.append(message)
    state["logs"] = logs
    logger.info(message)


def orchestrator_node(state: QiddiyaState) -> QiddiyaState:
    _append_log(state, "Orchestrator: starting planning workflow.")
    return state


def wait_time_predictor_node(state: QiddiyaState) -> QiddiyaState:
    _append_log(state, "Wait-Time Agent: computing simple demand-based forecast.")
    history = load_wait_history()
    forecast: Dict[str, int] = {}
    for attr_id in history["attraction_id"].unique():
        subset = history[history["attraction_id"] == attr_id]
        forecast[attr_id] = int(subset["wait_minutes"].mean())
    state["wait_time_forecast"] = forecast
    _append_log(
        state,
        f"Wait-Time Agent: produced forecast for {len(forecast)} attractions.",
    )
    return state


def route_optimizer_node(state: QiddiyaState) -> QiddiyaState:
    req = UserRequest.model_validate(state["user_request"])
    attractions = load_attractions()

    node_lookup = {a.id: a.node_id for a in attractions.values()}

    # If reflection trimmed the plan, only schedule those attractions (in geographic order) this pass
    refined = state.get("refined_attraction_ids") or []
    if refined:
        _append_log(
            state,
            f"Route Agent: re-building schedule from refined list ({len(refined)} attractions) after reflection.",
        )
        candidate = [aid for aid in refined if aid in attractions]
        ordered_ids = order_by_nearest_neighbor(candidate, node_lookup)
        state["refined_attraction_ids"] = []  # clear so we don't persist for future runs
    else:
        _append_log(state, "Route Agent: building schedule by geography (nearest-neighbor from hub).")
        must_do_ids: List[str] = []
        for name in req.must_do_attractions:
            attr = get_attraction_by_name(name)
            if attr:
                must_do_ids.append(attr.id)

        # Only schedule what the user asked for: no extra attractions
        if must_do_ids:
            candidate = must_do_ids
        else:
            # No must-dos selected: suggest a few by intensity
            other_ids = [
                a.id for a in attractions.values()
                if req.intensity_preference <= 3 or a.thrill_level <= 3
            ]
            candidate = other_ids[:8]  # cap suggestions when nothing selected

        # Order by space (minimize walking), not by user selection order
        ordered_ids = order_by_nearest_neighbor(candidate, node_lookup)
    wait_lookup = state.get("wait_time_forecast") or {}

    start_hour, start_minute = [int(p) for p in req.start_time.split(":")]
    start_minutes = start_hour * 60 + start_minute

    stops_raw, total_wait, total_walk = greedy_schedule(
        attractions_order=ordered_ids,
        start_time_minutes=start_minutes,
        walking_weight=float(6 - req.walking_tolerance),
        wait_time_lookup=wait_lookup,
        node_lookup=node_lookup,
    )

    stops = [ItineraryStop.model_validate(s).model_dump() for s in stops_raw]
    enjoyment = min(10.0, float(len(stops)) * (0.5 + 0.1 * req.intensity_preference))
    must_do_ids_for_coverage: List[str] = []
    for name in req.must_do_attractions:
        attr = get_attraction_by_name(name)
        if attr:
            must_do_ids_for_coverage.append(attr.id)
    must_do_set = set(must_do_ids_for_coverage)
    for s in stops:
        s["is_suggested"] = s["attraction_id"] not in must_do_set
    coverage = float(len([s for s in stops if s.get("attraction_id") in must_do_set])) / max(len(req.must_do_attractions), 1)

    plan = ItineraryPlan(
        visit_date=req.visit_date,
        total_wait_minutes=total_wait,
        total_walking_m=total_walk,
        coverage_score=coverage,
        enjoyment_score=enjoyment,
        stops=[ItineraryStop.model_validate(s) for s in stops],
        logs=state.get("logs", []),
    )
    state["raw_plan"] = plan.model_dump()
    _append_log(
        state,
        f"Route Agent: produced raw plan with {len(stops)} stops, "
        f"wait={total_wait}min, walk={total_walk}m.",
    )
    return state


def experience_writer_node(state: QiddiyaState) -> QiddiyaState:
    _append_log(state, "Guide Agent: generating visitor-friendly annotations (Groq if available).")
    raw_plan = ItineraryPlan.model_validate(state["raw_plan"])
    req = UserRequest.model_validate(state["user_request"])

    narrative_logs = generate_narrative_logs(raw_plan, req)
    annotated_logs = list(state.get("logs", [])) + narrative_logs
    final_plan = raw_plan.model_copy(update={"logs": annotated_logs})

    state["final_plan"] = final_plan.model_dump()
    _append_log(
        state,
        "Guide Agent: added narrative guidance to itinerary logs.",
    )
    return state


def critic_node(state: QiddiyaState) -> QiddiyaState:
    """
    Critic Agent: validates the plan against fixed criteria.
    Reflection runs only when at least one violation is found and reflection_round < 2.

    Criteria (violations):
    1. Must-do coverage: every requested must-do attraction must appear in the plan.
    2. Time window: total_wait_minutes must not exceed (end_time - start_time).
    3. Walking tolerance: total_walking_m must not exceed max_walk
       (max_walk = 3500 + 800 * (walking_tolerance - 1)).
    4. Enjoyment: enjoyment_score must be at least 3.0 (triggers reflection to add nearby stops).
    """
    _append_log(state, "Critic Agent: validating constraints and safety.")
    plan = ItineraryPlan.model_validate(state["final_plan"])
    req = UserRequest.model_validate(state["user_request"])

    violations: List[str] = []
    must_do_ids: List[str] = []

    for name in req.must_do_attractions:
        attr = get_attraction_by_name(name)
        if attr:
            must_do_ids.append(attr.id)
    covered = {s.attraction_id for s in plan.stops}
    missing_must_do = [mid for mid in must_do_ids if mid not in covered]
    if missing_must_do:
        n = len(missing_must_do)
        violations.append(
            f"{n} must-do attraction(s) are not scheduled."
            if n > 1
            else "One must-do attraction is not scheduled."
        )

    window_minutes = (
        int(req.end_time.split(":")[0]) * 60
        + int(req.end_time.split(":")[1])
        - int(req.start_time.split(":")[0]) * 60
        - int(req.start_time.split(":")[1])
    )
    if plan.total_wait_minutes > window_minutes:
        violations.append("Total wait time exceeds visit window.")

    # Walking cap: total walking must not exceed tolerance-based limit
    max_walk = 3500 + 800 * (req.walking_tolerance - 1)
    if plan.total_walking_m > max_walk:
        violations.append("Planned walking distance exceeds user tolerance.")

    # Low enjoyment: trigger reflection so we can suggest adding nearby optional stops
    if plan.enjoyment_score < 3.0:
        violations.append("Enjoyment score is low.")

    reflection_round = int(state.get("reflection_round", 0))
    if violations and reflection_round < 2:
        _append_log(
            state,
            f"Critic Agent: found violations, triggering reflection round {reflection_round + 1}.",
        )
        state["critique"] = "; ".join(violations)
        state["reflection_round"] = reflection_round + 1
    else:
        if violations:
            _append_log(
                state,
                "Critic Agent: violations remain but reflection limit reached.",
            )
        else:
            _append_log(state, "Critic Agent: plan accepted with no violations.")
        state["critique"] = "; ".join(violations) if violations else ""
    return state


def reflection_node(state: QiddiyaState) -> QiddiyaState:
    """
    Reflection: adjusts the plan based on the Critic's critique.
    - If the critique mentions "walking"/"distance": trim optional long-walk stops.
    - If the critique mentions "enjoyment": add up to 2 nearby optional attractions to boost the score.
    """
    critique: Optional[str] = state.get("critique")
    if not critique:
        _append_log(state, "Orchestrator: no critique to address, skipping reflection.")
        return state
    _append_log(
        state,
        f"Orchestrator: applying heuristic reflection based on critique: {critique}",
    )

    plan = ItineraryPlan.model_validate(state["final_plan"])
    req = UserRequest.model_validate(state["user_request"])
    attractions = load_attractions()
    node_lookup = {a.id: a.node_id for a in attractions.values()}
    c_lower = critique.lower()

    must_do_ids_set: set = set()
    for name in req.must_do_attractions:
        attr = get_attraction_by_name(name)
        if attr:
            must_do_ids_set.add(attr.id)

    # --- Enjoyment: add 1–2 nearby optional stops to boost the plan ---
    if "enjoyment" in c_lower and len(plan.stops) < 6:
        from .routing import shortest_path_distance

        current_ids = [s.attraction_id for s in plan.stops]
        last_node = plan.stops[-1].node_id if plan.stops else "HUB"
        optional_ids = [
            a.id for a in attractions.values()
            if a.id not in current_ids
            and (req.intensity_preference > 3 or a.thrill_level <= 3)
        ]
        # Nearest optional attractions from the last stop (up to 2)
        by_dist = sorted(
            optional_ids,
            key=lambda aid: shortest_path_distance(last_node, node_lookup[aid]),
        )
        # Add enough so we reach at least 5 stops (enjoyment >= 3.0 for low intensity)
        need = max(0, 5 - len(plan.stops))
        add_count = min(3, need)  # add up to 3, cap total at 6
        to_add = by_dist[: add_count] if add_count > 0 else []
        if to_add:
            refined_ids = current_ids + to_add
            state["refined_attraction_ids"] = refined_ids
            state["raw_plan"] = plan.model_dump()
            _append_log(
                state,
                f"Orchestrator: reflection adding {len(to_add)} nearby attraction(s) to boost enjoyment.",
            )
        else:
            state["refined_attraction_ids"] = current_ids
            _append_log(state, "Orchestrator: no optional attractions to add for enjoyment.")
        return state

    # --- Walking: trim optional long-walk stops ---
    filtered_stops: List[ItineraryStop] = []
    for stop in plan.stops:
        if stop.attraction_id in must_do_ids_set:
            filtered_stops.append(stop)
            continue
        if (
            ("walking" in c_lower or "distance" in c_lower)
            and req.walking_tolerance <= 2
            and stop.walking_distance_m > 300
        ):
            continue
        filtered_stops.append(stop)

    final_plan = plan.model_copy(update={"stops": filtered_stops})
    state["raw_plan"] = final_plan.model_dump()
    state["refined_attraction_ids"] = [s.attraction_id for s in filtered_stops]
    _append_log(
        state,
        f"Orchestrator: reflection adjusted plan to {len(filtered_stops)} stops (removed long-walk stops).",
    )
    return state