// Copyright (C) 2025 Emilis Bliūdžius
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
use core::num::NonZeroU8;

use crate::{
    diedto::DiedTo,
    error::GameError,
    game::night::{
        ActionComplete, CurrentResult, Night, NightState, ResponseOutcome, changes::NightChange,
    },
    message::night::{ActionPrompt, ActionResponse, ActionResult},
    player::Protection,
    role::{AlignmentEq, PreviousGuardianAction, RoleBlock, RoleTitle},
};

type Result<T> = core::result::Result<T, GameError>;

impl Night {
    pub(super) fn process(&self, resp: ActionResponse) -> Result<ResponseOutcome> {
        let current_prompt = match &self.night_state {
            NightState::Active {
                current_result: CurrentResult::GoBackToSleepAfterShown { .. },
                ..
            }
            | NightState::Active {
                current_result: CurrentResult::Result(ActionResult::GoBackToSleep),
                ..
            } => return Err(GameError::NightNeedsNext),
            NightState::Active {
                current_prompt,
                current_result: CurrentResult::None,
                ..
            }
            | NightState::Active {
                current_prompt,
                current_result: CurrentResult::Result(_),
                ..
            } => 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,
                            into: self
                                .changes_from_actions()
                                .into_iter()
                                .find_map(|c| match c {
                                    NightChange::Kill {
                                        target,
                                        died_to: DiedTo::Wolfpack { .. },
                                    } => Some(target),
                                    _ => None,
                                })
                                .ok_or(GameError::InvalidTarget)?,
                        }),
                    })),
                    _ => Err(GameError::InvalidMessageForGameState),
                };
            }
            ActionResponse::Continue => {
                if let ActionPrompt::Insomniac { character_id } = current_prompt {
                    return Ok(ActionComplete {
                        result: ActionResult::Insomniac(
                            self.get_visits_for(character_id.character_id),
                        ),
                        change: None,
                    }
                    .into());
                }
                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::LoneWolfKill {
                character_id,
                marked: Some(marked),
                ..
            } => Ok(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: Some(NightChange::Kill {
                    target: *marked,
                    died_to: DiedTo::LoneWolf {
                        killer: character_id.character_id,
                        night: self.night,
                    },
                }),
            }
            .into()),
            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(AlignmentEq::new(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: match &resp {
                        ActionResponse::Continue => None,
                        ActionResponse::Shapeshift => Some(NightChange::Shapeshift {
                            source: character_id.character_id,
                            into: self
                                .changes_from_actions()
                                .into_iter()
                                .find_map(|c| match c {
                                    NightChange::Kill {
                                        target,
                                        died_to: DiedTo::Wolfpack { .. },
                                    } => Some(target),
                                    _ => None,
                                })
                                .ok_or(GameError::InvalidTarget)?,
                        }),
                        _ => return Err(GameError::InvalidMessageForGameState),
                    },
                }))
            }
            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)
                }) && self.dies_tonight(*marked)?
                {
                    Ok(ActionComplete {
                        result: if matches!(result, ActionResult::RoleBlocked) {
                            ActionResult::BeholderSawNothing
                        } else {
                            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::Insomniac { .. } => Ok(ActionComplete {
                result: ActionResult::GoBackToSleep,
                change: None,
            }
            .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::LoneWolfKill { marked: 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),
        }
    }
}