werewolves/werewolves-proto/src/game/night.rs

use core::num::NonZeroU8;
use std::collections::VecDeque;

use serde::{Deserialize, Serialize};
use werewolves_macros::Extract;

use super::Result;
use crate::{
    character::{Character, CharacterId},
    diedto::DiedTo,
    error::GameError,
    game::{
        DateTime, Village,
        kill::{self, ChangesLookup},
    },
    message::night::{ActionPrompt, ActionResponse, ActionResult},
    player::Protection,
    role::{PreviousGuardianAction, RoleBlock, RoleTitle},
};

#[derive(Debug, Clone, Serialize, Deserialize, Extract)]
pub enum NightChange {
    RoleChange(CharacterId, RoleTitle),
    HunterTarget {
        source: CharacterId,
        target: CharacterId,
    },
    Kill {
        target: CharacterId,
        died_to: DiedTo,
    },
    RoleBlock {
        source: CharacterId,
        target: CharacterId,
        block_type: RoleBlock,
    },
    Shapeshift {
        source: CharacterId,
    },
    Protection {
        target: CharacterId,
        protection: Protection,
    },
    ElderReveal {
        elder: CharacterId,
    },
    MasonRecruit {
        mason_leader: CharacterId,
        recruiting: CharacterId,
    },
    EmpathFoundScapegoat {
        empath: CharacterId,
        scapegoat: CharacterId,
    },
}

enum BlockResolvedOutcome {
    PromptUpdate(ActionPrompt),
    ActionComplete(ActionResult, Option<NightChange>),
}

enum ResponseOutcome {
    PromptUpdate(ActionPrompt),
    ActionComplete(ActionComplete),
}

struct ActionComplete {
    pub result: ActionResult,
    pub change: Option<NightChange>,
}

impl From<ActionComplete> for ResponseOutcome {
    fn from(value: ActionComplete) -> Self {
        ResponseOutcome::ActionComplete(value)
    }
}

impl ActionPrompt {
    fn unless(&self) -> Option<Unless> {
        match &self {
            ActionPrompt::MasonsWake { .. }
            | ActionPrompt::WolvesIntro { .. }
            | ActionPrompt::RoleChange { .. }
            | ActionPrompt::Shapeshifter { .. }
            | ActionPrompt::ElderReveal { .. }
            | ActionPrompt::CoverOfDarkness => None,

            ActionPrompt::Arcanist {
                marked: (Some(marked1), Some(marked2)),
                ..
            } => Some(Unless::TargetsBlocked(*marked1, *marked2)),

            ActionPrompt::Seer {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Protector {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Gravedigger {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Hunter {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Militia {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::MapleWolf {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Guardian {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Adjudicator {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::PowerSeer {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Mortician {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Beholder {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::MasonLeaderRecruit {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Empath {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::Vindicator {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::PyreMaster {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::WolfPackKill {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::AlphaWolf {
                marked: Some(marked),
                ..
            }
            | ActionPrompt::DireWolf {
                marked: Some(marked),
                ..
            } => Some(Unless::TargetBlocked(*marked)),

            ActionPrompt::Seer { marked: None, .. }
            | ActionPrompt::Protector { marked: None, .. }
            | ActionPrompt::Gravedigger { marked: None, .. }
            | ActionPrompt::Hunter { marked: None, .. }
            | ActionPrompt::Militia { marked: None, .. }
            | ActionPrompt::MapleWolf { marked: None, .. }
            | ActionPrompt::Guardian { marked: None, .. }
            | ActionPrompt::Adjudicator { marked: None, .. }
            | ActionPrompt::PowerSeer { marked: None, .. }
            | ActionPrompt::Mortician { marked: None, .. }
            | ActionPrompt::Beholder { marked: None, .. }
            | ActionPrompt::MasonLeaderRecruit { marked: None, .. }
            | ActionPrompt::Empath { marked: None, .. }
            | ActionPrompt::Vindicator { marked: None, .. }
            | ActionPrompt::PyreMaster { marked: None, .. }
            | ActionPrompt::WolfPackKill { marked: None, .. }
            | ActionPrompt::AlphaWolf { marked: None, .. }
            | ActionPrompt::DireWolf { marked: None, .. }
            | ActionPrompt::Arcanist {
                marked: (Some(_), None),
                ..
            }
            | ActionPrompt::Arcanist {
                marked: (None, Some(_)),
                ..
            }
            | ActionPrompt::Arcanist {
                marked: (None, None),
                ..
            } => None,
        }
    }
}

impl Default for ActionComplete {
    fn default() -> Self {
        Self {
            result: ActionResult::GoBackToSleep,
            change: None,
        }
    }
}

enum Unless {
    TargetBlocked(CharacterId),
    TargetsBlocked(CharacterId, CharacterId),
}

impl From<Unless> for ActionResult {
    fn from(value: Unless) -> Self {
        match value {
            Unless::TargetBlocked(_) | Unless::TargetsBlocked(_, _) => ActionResult::RoleBlocked,
        }
    }
}

#[derive(Debug, Clone, Serialize, Deserialize)]
#[allow(clippy::large_enum_variant)]
enum NightState {
    Active {
        current_prompt: ActionPrompt,
        current_result: Option<ActionResult>,
    },
    Complete,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Night {
    village: Village,
    night: u8,
    action_queue: VecDeque<ActionPrompt>,
    used_actions: Vec<(ActionPrompt, ActionResult)>,
    changes: Vec<NightChange>,
    night_state: NightState,
}

impl Night {
    pub fn new(village: Village) -> Result<Self> {
        let night = match village.date_time() {
            DateTime::Day { number: _ } => return Err(GameError::NotNight),
            DateTime::Night { number } => number,
        };

        let filter = if village.executed_known_elder() {
            // there is a lynched elder, remove villager PRs from the prompts
            filter::no_village
        } else {
            filter::no_filter
        };

        let mut action_queue = village
            .characters()
            .into_iter()
            .filter(filter)
            .map(|c| c.night_action_prompts(&village))
            .collect::<Result<Box<[_]>>>()?
            .into_iter()
            .flatten()
            .chain((night > 0).then(|| ActionPrompt::WolfPackKill {
                marked: None,
                living_villagers: village.living_villagers(),
            }))
            .collect::<Vec<_>>();
        action_queue.sort_by(|left_prompt, right_prompt| {
            left_prompt
                .partial_cmp(right_prompt)
                .unwrap_or(core::cmp::Ordering::Equal)
        });
        let mut action_queue = VecDeque::from(action_queue);

        if night == 0 {
            action_queue.push_front(ActionPrompt::WolvesIntro {
                wolves: village
                    .living_wolf_pack_players()
                    .into_iter()
                    .map(|w| (w.identity(), w.role_title()))
                    .collect(),
            });
        }
        // let current_prompt = action_queue.pop_front().ok_or(GameError::NoNightActions)?;
        let night_state = NightState::Active {
            current_prompt: ActionPrompt::CoverOfDarkness,
            current_result: None,
        };

        let changes = Self::automatic_changes(&village, night);

        Ok(Self {
            night,
            changes,
            village,
            night_state,
            action_queue,
            used_actions: Vec::new(),
        })
    }

    /// changes that require no input (such as hunter firing)
    fn automatic_changes(village: &Village, night: u8) -> Vec<NightChange> {
        let mut changes = Vec::new();
        let night = match NonZeroU8::new(night) {
            Some(night) => night,
            None => return changes,
        };
        if !village.executed_known_elder() {
            village
                .dead_characters()
                .into_iter()
                .filter_map(|c| c.died_to().map(|d| (c, d)))
                .filter_map(|(c, d)| c.hunter().ok().and_then(|h| *h).map(|t| (c, t, d)))
                .filter_map(|(c, t, d)| match d.date_time() {
                    DateTime::Day { number } => (number.get() == night.get()).then_some((c, t)),
                    DateTime::Night { number: _ } => None,
                })
                .map(|(c, target)| NightChange::Kill {
                    target,
                    died_to: DiedTo::Hunter {
                        night,
                        killer: c.character_id(),
                    },
                })
                .for_each(|c| changes.push(c));
        }

        changes
    }

    pub fn previous_state(&mut self) -> Result<()> {
        return Err(GameError::NoPreviousState);
        let (prev_act, prev_result) = self.used_actions.pop().ok_or(GameError::NoPreviousState)?;
        log::info!("loading previous prompt: {prev_act:?}");
        match &self.night_state {
            NightState::Active {
                current_prompt,
                current_result: Some(current_result),
            } => {
                log::info!("removing current result: {current_result:?}");
                self.night_state = NightState::Active {
                    current_prompt: current_prompt.clone(),
                    current_result: None,
                };
            }
            NightState::Active {
                current_prompt,
                current_result: None,
            } => {
                log::info!("pushing current prompt to front of action queue: {current_prompt:?}");
                self.action_queue.push_front(current_prompt.clone());
                self.night_state = NightState::Active {
                    current_prompt: prev_act,
                    current_result: None,
                }
            }
            NightState::Complete => {
                self.night_state = NightState::Active {
                    current_prompt: prev_act,
                    current_result: None,
                };
            }
        }
        Ok(())
    }

    #[cfg(test)]
    pub fn action_queue(&self) -> Box<[ActionPrompt]> {
        self.action_queue.iter().cloned().collect()
    }

    pub fn collect_completed(&self) -> Result<Village> {
        if !matches!(self.night_state, NightState::Complete) {
            return Err(GameError::NotEndOfNight);
        }
        let mut new_village = self.village.clone();
        let mut changes = ChangesLookup::new(&self.changes);
        for change in self.changes.iter() {
            match change {
                NightChange::ElderReveal { elder } => {
                    new_village.character_by_id_mut(*elder)?.elder_reveal()
                }
                NightChange::RoleChange(character_id, role_title) => new_village
                    .character_by_id_mut(*character_id)?
                    .role_change(*role_title, DateTime::Night { number: self.night })?,
                NightChange::HunterTarget { source, target } => {
                    let hunter_character = new_village.character_by_id_mut(*source).unwrap();
                    hunter_character.hunter_mut()?.replace(*target);
                    if changes.killed(source).is_some()
                        && changes.protected(source).is_none()
                        && changes.protected(target).is_none()
                    {
                        new_village
                            .character_by_id_mut(*target)
                            .unwrap()
                            .kill(DiedTo::Hunter {
                                killer: *source,
                                night: NonZeroU8::new(self.night).unwrap(),
                            })
                    }
                }
                NightChange::Kill { target, died_to } => {
                    if let Some(kill) = kill::resolve_kill(
                        &mut changes,
                        target,
                        died_to,
                        self.night,
                        &self.village,
                    )? {
                        kill.apply_to_village(&mut new_village)?;
                    }
                }
                NightChange::Shapeshift { source } => {
                    if let Some(target) = changes.wolf_pack_kill_target()
                        && changes.protected(target).is_none()
                    {
                        let ss = new_village.character_by_id_mut(*source).unwrap();
                        ss.shapeshifter_mut().unwrap().replace(*target);
                        ss.kill(DiedTo::Shapeshift {
                            into: *target,
                            night: NonZeroU8::new(self.night).unwrap(),
                        });
                        // role change pushed in [apply_shapeshift]
                    }
                }
                NightChange::RoleBlock {
                    source: _,
                    target: _,
                    block_type: _,
                }
                | NightChange::Protection {
                    target: _,
                    protection: _,
                } => {}
                NightChange::MasonRecruit {
                    mason_leader,
                    recruiting,
                } => {
                    if new_village.character_by_id(*recruiting)?.is_wolf() {
                        new_village.character_by_id_mut(*mason_leader)?.kill(
                            DiedTo::MasonLeaderRecruitFail {
                                tried_recruiting: *recruiting,
                                night: self.night,
                            },
                        );
                    } else {
                        new_village
                            .character_by_id_mut(*mason_leader)?
                            .mason_leader_mut()?
                            .recruit(*recruiting);
                    }
                }
                NightChange::EmpathFoundScapegoat { empath, scapegoat } => {
                    new_village
                        .character_by_id_mut(*scapegoat)?
                        .role_change(RoleTitle::Villager, DateTime::Night { number: self.night })?;
                    *new_village.character_by_id_mut(*empath)?.empath_mut()? = true;
                }
            }
        }
        if new_village.is_game_over().is_none() {
            new_village.to_day()?;
        }
        Ok(new_village)
    }

    fn apply_mason_recruit(
        &mut self,
        mason_leader: CharacterId,
        recruiting: CharacterId,
    ) -> Result<ActionResult> {
        if self.village.character_by_id(recruiting)?.is_village() {
            if let Some(masons) = self.action_queue.iter_mut().find_map(|a| match a {
                ActionPrompt::MasonsWake {
                    character_id,
                    masons,
                } => (character_id.character_id == mason_leader).then_some(masons),
                _ => None,
            }) {
                let mut ext_masons = masons.to_vec();
                ext_masons.push(self.village.character_by_id(recruiting)?.identity());
                *masons = ext_masons.into_boxed_slice();
            } else {
                self.action_queue.push_front(ActionPrompt::MasonsWake {
                    character_id: self.village.character_by_id(mason_leader)?.identity(),
                    masons: Box::new([self.village.character_by_id(recruiting)?.identity()]),
                });
            }
            Ok(ActionResult::Continue)
        } else {
            Ok(ActionResult::GoBackToSleep)
        }
    }

    fn apply_shapeshift(&mut self, source: &CharacterId) -> Result<()> {
        if let Some(kill_target) = self.changes.iter().find_map(|c| match c {
            NightChange::Kill {
                target,
                died_to:
                    DiedTo::Wolfpack {
                        night: _,
                        killing_wolf: _,
                    },
            } => Some(*target),
            _ => None,
        }) {
            if self.changes.iter().any(|c| match c {
                NightChange::Protection {
                    target,
                    protection: _,
                } => target == &kill_target,
                _ => false,
            }) {
                // there is protection, so the kill doesn't happen -> no shapeshift
                return Ok(());
            }

            if self.changes.iter_mut().any(|c| {
                matches!(
                    c,
                    NightChange::Kill {
                        target: _,
                        died_to: DiedTo::Wolfpack {
                            night: _,
                            killing_wolf: _
                        }
                    }
                )
            }) {
                self.changes.push(NightChange::Kill {
                    target: *source,
                    died_to: DiedTo::Shapeshift {
                        into: kill_target,
                        night: NonZeroU8::new(self.night).unwrap(),
                    },
                });
            }
            self.changes
                .push(NightChange::Shapeshift { source: *source });
            self.action_queue.push_front(ActionPrompt::RoleChange {
                new_role: RoleTitle::Werewolf,
                character_id: self.village.character_by_id(kill_target)?.identity(),
            });
        }
        // Remove any further shapeshift prompts from the queue
        let mut new_queue = VecDeque::new();
        while let Some(prompt) = self.action_queue.pop_back() {
            match &prompt {
                ActionPrompt::Shapeshifter { character_id: _ } => {}
                _ => new_queue.push_front(prompt),
            }
        }
        self.action_queue = new_queue;
        Ok(())
    }

    pub fn received_response(&mut self, resp: ActionResponse) -> Result<ServerAction> {
        match self.received_response_with_role_blocks(resp)? {
            BlockResolvedOutcome::PromptUpdate(prompt) => match &mut self.night_state {
                NightState::Active {
                    current_result: Some(_),
                    ..
                } => Err(GameError::AwaitingResponse),
                NightState::Active { current_prompt, .. } => {
                    *current_prompt = prompt.clone();
                    Ok(ServerAction::Prompt(prompt))
                }
                NightState::Complete => Err(GameError::NightOver),
            },
            BlockResolvedOutcome::ActionComplete(mut result, Some(change)) => {
                match &mut self.night_state {
                    NightState::Active {
                        current_prompt: _,
                        current_result,
                    } => current_result.replace(result.clone()),
                    NightState::Complete => return Err(GameError::NightOver),
                };
                if let NightChange::Shapeshift { source } = &change {
                    // needs to be resolved _now_ so that the target can be woken
                    // for the role change with the wolves
                    self.apply_shapeshift(source)?;
                    return Ok(ServerAction::Result(
                        self.action_queue
                            .iter()
                            .next()
                            .and_then(|a| a.is_wolfy().then_some(ActionResult::Continue))
                            .unwrap_or(ActionResult::GoBackToSleep),
                    ));
                }
                if let NightChange::MasonRecruit {
                    mason_leader,
                    recruiting,
                } = &change
                {
                    result = self.apply_mason_recruit(*mason_leader, *recruiting)?;
                }
                self.changes.push(change);
                Ok(ServerAction::Result(result))
            }
            BlockResolvedOutcome::ActionComplete(result, None) => {
                match &mut self.night_state {
                    NightState::Active {
                        current_prompt: _,
                        current_result,
                    } => {
                        current_result.replace(result.clone());
                    }
                    NightState::Complete => return Err(GameError::NightOver),
                };
                Ok(ServerAction::Result(result))
            }
        }
    }

    fn received_response_consecutive_wolves_dont_sleep(
        &self,
        resp: ActionResponse,
    ) -> Result<ResponseOutcome> {
        let (current_cover, current_wolfy) = self
            .current_prompt()
            .map(|current_prompt| {
                (
                    *current_prompt == ActionPrompt::CoverOfDarkness,
                    current_prompt.is_wolfy(),
                )
            })
            .unwrap_or_default();
        let next_wolfy = self
            .action_queue
            .iter()
            .next()
            .map(|a| a.is_wolfy())
            .unwrap_or_default();

        if current_cover && let ActionResponse::Continue = &resp {
            return Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::Continue,
                change: None,
            }));
        }

        match (
            self.received_response_inner(resp)?,
            current_wolfy,
            next_wolfy,
        ) {
            (ResponseOutcome::PromptUpdate(p), _, _) => Ok(ResponseOutcome::PromptUpdate(p)),
            (
                ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GoBackToSleep,
                    change: Some(NightChange::Shapeshift { source }),
                }),
                true,
                _,
            ) => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::Continue,
                change: Some(NightChange::Shapeshift { source }),
            })),
            (
                ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GoBackToSleep,
                    change,
                }),
                true,
                true,
            ) => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::Continue,
                change,
            })),
            (outcome, _, _) => Ok(outcome),
        }
    }

    fn received_response_with_role_blocks(
        &self,
        resp: ActionResponse,
    ) -> Result<BlockResolvedOutcome> {
        match self.received_response_consecutive_wolves_dont_sleep(resp)? {
            ResponseOutcome::PromptUpdate(update) => Ok(BlockResolvedOutcome::PromptUpdate(update)),
            ResponseOutcome::ActionComplete(ActionComplete { result, change }) => {
                match self.current_prompt().ok_or(GameError::NightOver)?.unless() {
                    Some(Unless::TargetBlocked(unless_blocked)) => {
                        if self.changes.iter().any(|c| match c {
                            NightChange::RoleBlock {
                                source: _,
                                target,
                                block_type: _,
                            } => target == &unless_blocked,
                            _ => false,
                        }) {
                            Ok(BlockResolvedOutcome::ActionComplete(
                                ActionResult::RoleBlocked,
                                None,
                            ))
                        } else {
                            Ok(BlockResolvedOutcome::ActionComplete(result, change))
                        }
                    }
                    Some(Unless::TargetsBlocked(unless_blocked1, unless_blocked2)) => {
                        if self.changes.iter().any(|c| match c {
                            NightChange::RoleBlock {
                                source: _,
                                target,
                                block_type: _,
                            } => target == &unless_blocked1 || target == &unless_blocked2,
                            _ => false,
                        }) {
                            Ok(BlockResolvedOutcome::ActionComplete(
                                ActionResult::RoleBlocked,
                                None,
                            ))
                        } else {
                            Ok(BlockResolvedOutcome::ActionComplete(result, change))
                        }
                    }
                    None => Ok(BlockResolvedOutcome::ActionComplete(result, change)),
                }
            }
        }
    }

    fn received_response_inner(&self, resp: ActionResponse) -> Result<ResponseOutcome> {
        let current_prompt = match &self.night_state {
            NightState::Active {
                current_prompt: _,
                current_result: Some(_),
            } => return Err(GameError::NightNeedsNext),
            NightState::Active {
                current_prompt,
                current_result: None,
            } => current_prompt,
            NightState::Complete => return Err(GameError::NightOver),
        };

        match resp {
            ActionResponse::MarkTarget(mark) => {
                return Ok(ResponseOutcome::PromptUpdate(
                    current_prompt.with_mark(mark)?,
                ));
            }
            ActionResponse::Shapeshift => {
                return match current_prompt {
                    ActionPrompt::Shapeshifter {
                        character_id: source,
                    } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                        result: ActionResult::GoBackToSleep,
                        change: Some(NightChange::Shapeshift {
                            source: source.character_id,
                        }),
                    })),
                    _ => Err(GameError::InvalidMessageForGameState),
                };
            }
            ActionResponse::Continue => {
                if let ActionPrompt::RoleChange {
                    character_id,
                    new_role,
                } = current_prompt
                {
                    return Ok(ResponseOutcome::ActionComplete(ActionComplete {
                        result: ActionResult::GoBackToSleep,
                        change: Some(NightChange::RoleChange(
                            character_id.character_id,
                            *new_role,
                        )),
                    }));
                }
            }
        };

        match current_prompt {
            ActionPrompt::RoleChange { .. }
            | ActionPrompt::WolvesIntro { .. }
            | ActionPrompt::CoverOfDarkness => {
                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GoBackToSleep,
                    change: None,
                }))
            }
            ActionPrompt::ElderReveal { character_id } => {
                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GoBackToSleep,
                    change: Some(NightChange::ElderReveal {
                        elder: character_id.character_id,
                    }),
                }))
            }
            ActionPrompt::Seer {
                marked: Some(marked),
                ..
            } => {
                let alignment = self.village.character_by_id(*marked)?.alignment();
                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::Seer(alignment),
                    change: None,
                }))
            }
            ActionPrompt::Protector {
                marked: Some(marked),
                character_id,
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Protection {
                    target: *marked,
                    protection: Protection::Protector {
                        source: character_id.character_id,
                    },
                }),
            })),
            ActionPrompt::Arcanist {
                marked: (Some(marked1), Some(marked2)),
                ..
            } => {
                let same = self.village.character_by_id(*marked1)?.alignment()
                    == self.village.character_by_id(*marked2)?.alignment();

                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::Arcanist { same },
                    change: None,
                }))
            }
            ActionPrompt::Gravedigger {
                marked: Some(marked),
                ..
            } => {
                let dig_role = self.village.character_by_id(*marked)?.gravedigger_dig();
                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GraveDigger(dig_role),
                    change: None,
                }))
            }
            ActionPrompt::Hunter {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::HunterTarget {
                    source: character_id.character_id,
                    target: *marked,
                }),
            })),
            ActionPrompt::Militia {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Kill {
                    target: *marked,
                    died_to: DiedTo::Militia {
                        killer: character_id.character_id,
                        night: NonZeroU8::new(self.night)
                            .ok_or(GameError::InvalidMessageForGameState)?,
                    },
                }),
            })),
            ActionPrompt::Militia { marked: None, .. } => {
                Ok(ResponseOutcome::ActionComplete(Default::default()))
            }
            ActionPrompt::MapleWolf {
                character_id,
                kill_or_die,
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Kill {
                    target: *marked,
                    died_to: DiedTo::MapleWolf {
                        source: character_id.character_id,
                        night: NonZeroU8::new(self.night)
                            .ok_or(GameError::InvalidMessageForGameState)?,
                        starves_if_fails: *kill_or_die,
                    },
                }),
            })),
            ActionPrompt::MapleWolf { marked: None, .. } => {
                Ok(ResponseOutcome::ActionComplete(Default::default()))
            }
            ActionPrompt::Guardian {
                character_id,
                previous: None,
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Protection {
                    target: *marked,
                    protection: Protection::Guardian {
                        source: character_id.character_id,
                        guarding: false,
                    },
                }),
            })),
            ActionPrompt::Guardian {
                character_id,
                previous: Some(PreviousGuardianAction::Guard(prev_target)),
                marked: Some(marked),
                ..
            } => {
                if prev_target.character_id == *marked {
                    return Err(GameError::InvalidTarget);
                }
                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GoBackToSleep,
                    change: Some(NightChange::Protection {
                        target: *marked,
                        protection: Protection::Guardian {
                            source: character_id.character_id,
                            guarding: false,
                        },
                    }),
                }))
            }
            ActionPrompt::Guardian {
                character_id,
                previous: Some(PreviousGuardianAction::Protect(prev_protect)),
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Protection {
                    target: *marked,
                    protection: Protection::Guardian {
                        source: character_id.character_id,
                        guarding: prev_protect.character_id == *marked,
                    },
                }),
            })),
            ActionPrompt::WolfPackKill {
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Kill {
                    target: *marked,
                    died_to: DiedTo::Wolfpack {
                        killing_wolf: self
                            .village
                            .killing_wolf()
                            .ok_or(GameError::NoWolves)?
                            .character_id(),
                        night: NonZeroU8::new(self.night)
                            .ok_or(GameError::InvalidMessageForGameState)?,
                    },
                }),
            })),
            ActionPrompt::Shapeshifter { character_id } => {
                Ok(ResponseOutcome::ActionComplete(ActionComplete {
                    result: ActionResult::GoBackToSleep,
                    change: Some(NightChange::Shapeshift {
                        source: character_id.character_id,
                    }),
                }))
            }
            ActionPrompt::AlphaWolf {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Kill {
                    target: *marked,
                    died_to: DiedTo::AlphaWolf {
                        killer: character_id.character_id,
                        night: NonZeroU8::new(self.night)
                            .ok_or(GameError::InvalidMessageForGameState)?,
                    },
                }),
            })),
            ActionPrompt::AlphaWolf { marked: None, .. } => {
                Ok(ResponseOutcome::ActionComplete(Default::default()))
            }
            ActionPrompt::DireWolf {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ResponseOutcome::ActionComplete(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::RoleBlock {
                    source: character_id.character_id,
                    target: *marked,
                    block_type: RoleBlock::Direwolf,
                }),
            })),
            ActionPrompt::Adjudicator {
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::Adjudicator {
                    killer: self.village.character_by_id(*marked)?.killer(),
                },
                change: None,
            }
            .into()),
            ActionPrompt::PowerSeer {
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::PowerSeer {
                    powerful: self.village.character_by_id(*marked)?.powerful(),
                },
                change: None,
            }
            .into()),
            ActionPrompt::Mortician {
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::Mortician(
                    self.village
                        .character_by_id(*marked)?
                        .died_to()
                        .ok_or(GameError::InvalidTarget)?
                        .title(),
                ),
                change: None,
            }
            .into()),
            ActionPrompt::Beholder {
                marked: Some(marked),
                ..
            } => {
                if let Some(result) = self.used_actions.iter().find_map(|(prompt, result)| {
                    prompt.matches_beholding(*marked).then_some(result)
                }) {
                    Ok(ActionComplete {
                        result: result.clone(),
                        change: None,
                    }
                    .into())
                } else {
                    Ok(ActionComplete {
                        result: ActionResult::GoBackToSleep,
                        change: None,
                    }
                    .into())
                }
            }
            ActionPrompt::MasonsWake { .. } => Ok(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: None,
            }
            .into()),
            ActionPrompt::MasonLeaderRecruit {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::Continue,
                change: Some(NightChange::MasonRecruit {
                    mason_leader: character_id.character_id,
                    recruiting: *marked,
                }),
            }
            .into()),
            ActionPrompt::Empath {
                character_id,
                marked: Some(marked),
                ..
            } => {
                let marked = self.village.character_by_id(*marked)?;
                let scapegoat = marked.role_title() == RoleTitle::Scapegoat;

                Ok(ActionComplete {
                    result: ActionResult::Empath { scapegoat },
                    change: scapegoat.then(|| NightChange::EmpathFoundScapegoat {
                        empath: character_id.character_id,
                        scapegoat: marked.character_id(),
                    }),
                }
                .into())
            }
            ActionPrompt::Vindicator {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Protection {
                    target: *marked,
                    protection: Protection::Vindicator {
                        source: character_id.character_id,
                    },
                }),
            }
            .into()),
            ActionPrompt::PyreMaster {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: NonZeroU8::new(self.night).map(|night| NightChange::Kill {
                    target: *marked,
                    died_to: DiedTo::PyreMaster {
                        killer: character_id.character_id,
                        night,
                    },
                }),
            }
            .into()),

            ActionPrompt::PyreMaster { marked: None, .. }
            | ActionPrompt::MasonLeaderRecruit { marked: None, .. } => Ok(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: None,
            }
            .into()),

            ActionPrompt::Adjudicator { marked: None, .. }
            | ActionPrompt::PowerSeer { marked: None, .. }
            | ActionPrompt::Mortician { marked: None, .. }
            | ActionPrompt::Beholder { marked: None, .. }
            | ActionPrompt::Empath { marked: None, .. }
            | ActionPrompt::Vindicator { marked: None, .. }
            | ActionPrompt::Protector { marked: None, .. }
            | ActionPrompt::Arcanist {
                marked: (None, None),
                ..
            }
            | ActionPrompt::Arcanist {
                marked: (None, Some(_)),
                ..
            }
            | ActionPrompt::Arcanist {
                marked: (Some(_), None),
                ..
            }
            | ActionPrompt::Gravedigger { marked: None, .. }
            | ActionPrompt::Hunter { marked: None, .. }
            | ActionPrompt::Guardian { marked: None, .. }
            | ActionPrompt::WolfPackKill { marked: None, .. }
            | ActionPrompt::DireWolf { marked: None, .. }
            | ActionPrompt::Seer { marked: None, .. } => Err(GameError::InvalidMessageForGameState),
        }
    }

    pub const fn village(&self) -> &Village {
        &self.village
    }

    pub const fn current_result(&self) -> Option<&ActionResult> {
        match &self.night_state {
            NightState::Active {
                current_prompt: _,
                current_result,
            } => current_result.as_ref(),
            NightState::Complete => None,
        }
    }

    pub const fn current_prompt(&self) -> Option<&ActionPrompt> {
        match &self.night_state {
            NightState::Active {
                current_prompt,
                current_result: _,
            } => Some(current_prompt),
            NightState::Complete => None,
        }
    }

    pub const fn current_character_id(&self) -> Option<CharacterId> {
        match &self.night_state {
            NightState::Active {
                current_prompt,
                current_result: _,
            } => match current_prompt {
                ActionPrompt::ElderReveal { character_id }
                | ActionPrompt::RoleChange { character_id, .. }
                | ActionPrompt::Seer { character_id, .. }
                | ActionPrompt::Protector { character_id, .. }
                | ActionPrompt::Arcanist { character_id, .. }
                | ActionPrompt::Gravedigger { character_id, .. }
                | ActionPrompt::Hunter { character_id, .. }
                | ActionPrompt::Militia { character_id, .. }
                | ActionPrompt::MapleWolf { character_id, .. }
                | ActionPrompt::Guardian { character_id, .. }
                | ActionPrompt::Shapeshifter { character_id }
                | ActionPrompt::AlphaWolf { character_id, .. }
                | ActionPrompt::Adjudicator { character_id, .. }
                | ActionPrompt::PowerSeer { character_id, .. }
                | ActionPrompt::Mortician { character_id, .. }
                | ActionPrompt::Beholder { character_id, .. }
                | ActionPrompt::MasonsWake { character_id, .. }
                | ActionPrompt::MasonLeaderRecruit { character_id, .. }
                | ActionPrompt::Empath { character_id, .. }
                | ActionPrompt::Vindicator { character_id, .. }
                | ActionPrompt::PyreMaster { character_id, .. }
                | ActionPrompt::DireWolf { character_id, .. } => Some(character_id.character_id),
                ActionPrompt::WolvesIntro { wolves: _ }
                | ActionPrompt::WolfPackKill { .. }
                | ActionPrompt::CoverOfDarkness => None,
            },
            NightState::Complete => None,
        }
    }

    pub fn current_character(&self) -> Option<&Character> {
        self.current_character_id()
            .and_then(|id| self.village.character_by_id(id).ok())
    }

    pub const fn complete(&self) -> bool {
        matches!(self.night_state, NightState::Complete)
    }

    pub fn next(&mut self) -> Result<()> {
        match &self.night_state {
            NightState::Active {
                current_prompt,
                current_result: Some(result),
            } => {
                self.used_actions
                    .push((current_prompt.clone(), result.clone()));
            }
            NightState::Active {
                current_prompt: _,
                current_result: None,
            } => return Err(GameError::AwaitingResponse),
            NightState::Complete => return Err(GameError::NightOver),
        }
        if let Some(prompt) = self.action_queue.pop_front() {
            self.night_state = NightState::Active {
                current_prompt: prompt,
                current_result: None,
            };
        } else {
            self.night_state = NightState::Complete;
        }

        Ok(())
    }

    pub const fn changes(&self) -> &[NightChange] {
        self.changes.as_slice()
    }
}

pub enum ServerAction {
    Prompt(ActionPrompt),
    Result(ActionResult),
}

mod filter {
    use crate::character::Character;

    pub fn no_filter(_: &Character) -> bool {
        true
    }

    pub fn no_village(c: &Character) -> bool {
        !c.is_village()
    }
}