"""阵营技能树系统 - 允许阵营通过累积能量解锁技能"""
from typing import List, Optional
from .models import (
    WorldState, FactionSkill, FactionSkillTree, FactionSkills
)


def get_default_faction_skills() -> FactionSkills:
    """返回默认技能树配置"""
    return FactionSkills(
        optimists=FactionSkillTree(
            skills={
                "festival_boost": FactionSkill(
                    unlocked=False,
                    cost=10,
                    effect="increase_positive_emotion",
                    requires=[]
                ),
                "unity": FactionSkill(
                    unlocked=False,
                    cost=20,
                    effect="reduce_conflict",
                    requires=["festival_boost"]
                )
            }
        ),
        fearful=FactionSkillTree(
            skills={
                "panic_spread": FactionSkill(
                    unlocked=False,
                    cost=10,
                    effect="increase_fear",
                    requires=[]
                ),
                "control": FactionSkill(
                    unlocked=False,
                    cost=20,
                    effect="suppress_others",
                    requires=["panic_spread"]
                )
            }
        )
    )


def _check_requires_met(skill_tree: FactionSkillTree, requires: List[str]) -> bool:
    """检查前置技能是否已解锁"""
    for req in requires:
        if req not in skill_tree.skills:
            return False
        if not skill_tree.skills[req].unlocked:
            return False
    return True


def check_and_unlock_skills(state: WorldState) -> List[str]:
    """检查并解锁技能

    规则：
    1. faction.power >= skill.cost
    2. 技能尚未解锁
    3. 所有 requires 已解锁

    返回：本次解锁的技能列表
    """
    unlocked = []

    # 检查乐观派技能
    for skill_id, skill in state.faction_skills.optimists.skills.items():
        if skill.unlocked:
            continue
        if state.factions.optimists.power < skill.cost:
            continue
        if not _check_requires_met(state.faction_skills.optimists, skill.requires):
            continue

        # 解锁技能
        skill.unlocked = True
        state.factions.optimists.power -= skill.cost
        unlocked.append(f"optimists:{skill_id}")

    # 检查恐惧派技能
    for skill_id, skill in state.faction_skills.fearful.skills.items():
        if skill.unlocked:
            continue
        if state.factions.fearful.power < skill.cost:
            continue
        if not _check_requires_met(state.faction_skills.fearful, skill.requires):
            continue

        # 解锁技能
        skill.unlocked = True
        state.factions.fearful.power -= skill.cost
        unlocked.append(f"fearful:{skill_id}")

    return unlocked


def apply_skill_effects(state: WorldState) -> None:
    """应用已解锁技能的持续效果

    效果说明：
    - increase_positive_emotion: 每 tick 提升 town_mood +1
    - reduce_conflict: 降低恐惧派能量增长（每 tick -1）
    - increase_fear: 每 tick 降低 town_mood -1
    - suppress_others: 降低乐观派能量增长（每 tick -1）
    """
    # 乐观派技能效果
    for skill_id, skill in state.faction_skills.optimists.skills.items():
        if not skill.unlocked:
            continue

        if skill.effect == "increase_positive_emotion":
            state.town_mood = min(10, state.town_mood + 1)
        elif skill.effect == "reduce_conflict":
            state.factions.fearful.power = max(0, state.factions.fearful.power - 1)

    # 恐惧派技能效果
    for skill_id, skill in state.faction_skills.fearful.skills.items():
        if not skill.unlocked:
            continue

        if skill.effect == "increase_fear":
            state.town_mood = max(-10, state.town_mood - 1)
        elif skill.effect == "suppress_others":
            state.factions.optimists.power = max(0, state.factions.optimists.power - 1)