use uuid::Uuid;
use rand::prelude::*;

// Db Commons
use serde_cbor::{from_slice, to_vec};
use postgres::transaction::Transaction;
use failure::Error;
use failure::err_msg;

use account::Account;
use rpc::{GameAbilityParams, GamePveParams};
use cryp::{Cryp, CrypStat, Stat};

#[derive(Debug,Clone,Copy,PartialEq,Serialize,Deserialize)]
pub struct Roll {
    pub base: u64,
    pub result: u64,
}

#[derive(Debug,Clone,Copy,PartialEq,Serialize,Deserialize)]
pub enum AbilityKind {
  Attack,
  Block,
  Heal,
}

#[derive(Debug,Clone,Copy,PartialEq,Serialize,Deserialize)]
pub struct Ability {
    id: Uuid,
    kind: AbilityKind,
    cryp_id: Uuid,
    roll: Option<Roll>,
    target_cryp_id: Option<Uuid>,
    target_team_id: Uuid,
}

impl Ability {
    pub fn new(cryp_id: Uuid, target_team_id: Uuid, kind: AbilityKind) -> Ability {
        return Ability {
            id: Uuid::new_v4(),
            cryp_id,
            target_cryp_id: None,
            target_team_id,
            roll: None,
            kind,
        };
    }

    fn roll(&self, c: &Cryp) -> Roll {
        let mut rng = thread_rng();
        let base: u64 = rng.gen();

        let stat = match self.kind {
            AbilityKind::Attack => &c.str,
            AbilityKind::Block => &c.str,
            AbilityKind::Heal => &c.int,
        };

        let mut roll = Roll { base, result: base };

        // // apply skills
        // roll = c.skills.iter().fold(roll, |roll, s| s.apply(roll));

        // finally combine with stat
        println!("{:064b}   <- finalised", roll.result);
        roll.result = roll.result & stat.value;

        println!("{:064b} & <- attribute roll", stat.value);
        println!("{:064b} = {:?}", roll.result, roll.result);
        println!("");

        return roll;
    }

    pub fn resolve(&mut self, cryp: &mut Cryp, target: &mut Cryp) -> &mut Ability {
        let roll = self.roll(&cryp);

        println!("{:?} gettin clapped for {:?}", target.name, roll.result);
        target.hp.reduce(roll.result);
        self
    }

    pub fn set_target(&mut self, cryp_id: Uuid) -> &mut Ability {
        self.target_cryp_id = Some(cryp_id);
        self
    }
}

#[derive(Debug,Clone,Copy,PartialEq,Serialize,Deserialize)]
pub enum Phase {
    Start,
    Ability,
    Target,
    Damage,
    Finish,
}

#[derive(Debug,Clone,Serialize,Deserialize)]
pub struct Team {
    id: Uuid,
    cryps: Vec<Cryp>,
    abilities: Vec<Ability>,
    incoming: Vec<Ability>,
}

impl Team {
    pub fn new(account: Uuid) -> Team {
        return Team {
            id: account,
            cryps: vec![],
            abilities: vec![],
            incoming: vec![],
        };
    }

    pub fn set_cryps(&mut self, cryps: Vec<Cryp>) -> &mut Team {
        self.cryps = cryps;
        self
    }

    pub fn cryp_by_id(&mut self, id: Uuid) -> Option<&mut Cryp> {
        self.cryps.iter_mut().find(|c| c.id == id)
    }

    pub fn ability_by_id(&mut self, id: Uuid) -> &mut Ability {
        match self.incoming.iter_mut().find(|a| a.id == id) {
            Some(a) => a,
            None => panic!("abiltity not in game"),
        }
    }
}

#[derive(Debug,Clone,Serialize,Deserialize)]
pub struct Game {
    pub id: Uuid,
    pub team_size: usize,
    pub team_num: usize,
    pub teams: Vec<Team>,
    pub is_pve: bool,
    pub phase: Phase,
    pub log: Vec<String>,
}

impl Game {
    pub fn new() -> Game {
        return Game {
            id: Uuid::new_v4(),
            team_size: 0,
            team_num: 0,
            teams: vec![],
            is_pve: true,
            phase: Phase::Start,
            log: vec![],
        };
    }

    pub fn set_team_num(&mut self, size: usize) -> &mut Game {
        self.team_num = size;
        self
    }

    pub fn set_team_size(&mut self, size: usize) -> &mut Game {
        self.team_size = size;
        self
    }

    pub fn add_team(&mut self, team: Team) -> &mut Game {
        if self.teams.len() == self.team_num {
            panic!("maximum number of teams");
        }
        self.teams.push(team);
        self
    }

    // handle missing team properly
    pub fn team_by_id(&mut self, id: Uuid) -> &mut Team {
        match self.teams.iter_mut().find(|t| t.id == id) {
            Some(t) => t,
            None => panic!("id not in game {:?}", id),
        }
    }

    pub fn cryp_by_id(&mut self, id: Uuid) -> &mut Cryp {
        for team in self.teams.iter_mut() {
            let in_team = team.cryp_by_id(id);
            if in_team.is_some() {
                return in_team.unwrap();
            }
        }

        panic!("cryp not in game");
    }

    fn replace_cryp(&mut self, updated: Cryp) -> &mut Game {
        for team in self.teams.iter_mut() {
            if let Some(index) = team.cryps.iter().position(|c| c.id == updated.id) {
                team.cryps.remove(index);
                team.cryps.push(updated);
                break;
            }
        }
        self
    }

    pub fn can_start(&self) -> bool {
        self.teams.len() == self.team_num
    }

    pub fn start(&mut self) -> &mut Game {
        self.ability_phase_start();
        self
    }

    pub fn ability_phase_start(&mut self) -> &mut Game {
        if ![Phase::Start, Phase::Damage].contains(&self.phase) {
            panic!("game not in damage or start phase");
        }

        self.phase = Phase::Ability;
        for team in self.teams.iter_mut() {
            team.abilities.clear();
            team.incoming.clear();
        }
        self
    }

    // abilities can target any team, but we have to check if the caller is the owner of the cryp
    // and that the cryp has the ability they are trying to add
    pub fn add_ability(&mut self, team_id: Uuid, cryp_id: Uuid, target_team_id: Uuid, kind: AbilityKind) -> Uuid {
        let team = self.team_by_id(team_id);
        match team.cryp_by_id(cryp_id) {
            Some(c) => c,
            None => panic!("cryp not in team"),
        };

        let ability = Ability::new(cryp_id, target_team_id, kind);
        team.abilities.push(ability);

        return ability.id;
    }

    pub fn ability_phase_finished(&self) -> bool {
        self.teams.iter().all(|t| t.abilities.len() == self.team_size)
    }

    // move all abilities into their target team's targets list
    pub fn targets_phase_start(&mut self) -> &mut Game {
        if self.phase != Phase::Ability {
            panic!("game not in ability phase");
        }

        self.phase = Phase::Target;

        // have to clone the teams because we change them while iterating
        let teams = self.teams.clone();

        for mut team in teams {
            for ability in team.abilities.iter_mut() {
                let target_team = self.team_by_id(ability.target_team_id);
                target_team.incoming.push(*ability);
            }
        }

        self
    }

    // targets can only be added by the owner of the team
    pub fn add_target(&mut self, team_id: Uuid, cryp_id: Uuid, ability_id: Uuid) -> &mut Ability {
        // whose team is this?
        let team = self.team_by_id(team_id);

        // is the target in the team?
        match team.cryp_by_id(cryp_id) {
            Some(c) => c,
            None => panic!("cryp not in team"),
        };

        // set the target
        let ability = team.ability_by_id(ability_id);
        ability.set_target(cryp_id)
    }

    pub fn target_phase_finished(&self) -> bool {
        self.teams.iter().all(|t| t.incoming.iter().all(|i| i.target_cryp_id.is_some()))
    }

    // requires no input
    // just do it
    pub fn damage_phase_start(&mut self) -> &mut Game {
        if self.phase != Phase::Target {
            panic!("game not in target phase");
        }

        self.phase = Phase::Damage;

        self.resolve_abilities();

        if self.is_finished() {
            self.phase = Phase::Finish;
            return self;
        }

        self.ability_phase_start();

        self
    }

    fn resolve_abilities(&mut self) -> &mut Game {
        if self.phase != Phase::Damage {
            panic!("game not in damage phase");
        }

        // sometimes... you just gotta
        for team in self.teams.clone().iter_mut() {
            for incoming in team.incoming.clone().iter_mut() {
                // they better fuckin be there
                let mut cryp = self.cryp_by_id(incoming.target_cryp_id.unwrap()).clone();
                let mut target_cryp = self.cryp_by_id(incoming.target_cryp_id.unwrap()).clone();
                incoming.resolve(&mut cryp, &mut target_cryp);
                self.replace_cryp(target_cryp);
            }
        }
        self
    }

    pub fn is_finished(&self) -> bool {
        self.teams.iter().any(|t| t.cryps.iter().all(|c| c.is_ko()))
    }
}


// add client function call
// check for cryp ability ownership
// check for game participation

pub fn game_ability(params: GameAbilityParams, tx: &mut Transaction, account: &Account) -> Result<Game, Error> {
    let query = "
        SELECT *
        FROM games
        WHERE id = $1
    ";

    let result = tx
        .query(query, &[&params.game_id])?;

    let returned = match result.iter().next() {
        Some(row) => row,
        None => return Err(err_msg("game not found")),
    };

    // tells from_slice to cast into a cryp
    let game_bytes: Vec<u8> = returned.get("data");
    let mut game = from_slice::<Game>(&game_bytes)?;

    game.add_ability(account.id, params.cryp_id, params.target_team_id, params.kind);

    return game_write(game, tx);
}

pub fn game_new(game: Game, tx: &mut Transaction) -> Result<Game, Error> {
    let game_bytes = to_vec(&game)?;

    let query = "
        INSERT INTO games (id, data)
        VALUES ($1, $2, $3)
        RETURNING id, account;
    ";

    let result = tx
        .query(query, &[&game_bytes, &game.id])?;

    let _returned = result.iter().next().expect("no row returned");

    println!("{:?} wrote game", game.id);

    return Ok(game);
}

pub fn game_write(game: Game, tx: &mut Transaction) -> Result<Game, Error> {
    let game_bytes = to_vec(&game)?;

    let query = "
        UPDATE games
        SET data = $1
        WHERE id = $2
        RETURNING id, data;
    ";

    let result = tx
        .query(query, &[&game_bytes, &game.id])?;

    let _returned = result.iter().next().expect("no row returned");

    println!("{:?} wrote game", game.id);

    return Ok(game);
}

fn generate_mob(plr: &Cryp) -> Cryp {
    let mut rng = thread_rng();

    // rng panics on min == max
    let mob_lvl: u8 = match plr.lvl {
      1 => 1,
      _ => rng.gen_range(1, plr.lvl)
    };

    return Cryp::new()
        .named(&"bamboo basher".to_string())
        .level(mob_lvl)
        .create();

}

pub fn game_pve(params: GamePveParams, tx: &mut Transaction, account: &Account) -> Result<Game, Error> {
    let query = "
        SELECT *
        FROM cryps
        WHERE id = $1
        AND account = $2;
    ";

    let result = tx
        .query(query, &[&params.id, &account.id])?;

    let returned = match result.iter().next() {
        Some(row) => row,
        None => return Err(err_msg("cryp not found")),
    };

    // tells from_slice to cast into a cryp
    let cryp_bytes: Vec<u8> = returned.get("data");
    let plr: Cryp = from_slice::<Cryp>(&cryp_bytes)?;

    // TEMP
    if plr.hp.value == 0 {
      return Err(err_msg("cryp is ko"));
        // plr.rez();
    }

    let mob = generate_mob(&plr);

    let mut game = Game::new();

    game
        .set_team_num(2)
        .set_team_size(1);

    let mut plr_team = Team::new(account.id);
    plr_team
        .set_cryps(vec![plr]);

    let mut mob_team = Team::new(Uuid::nil());
    mob_team
        .set_cryps(vec![mob]);

    game
        .add_team(plr_team)
        .add_team(mob_team);

    game.start();

    Ok(game)
}

#[cfg(test)]
mod tests {
    use game::*;
    use cryp::*;

    #[test]
    fn game_test() {
        let x = Cryp::new()
            .named(&"pronounced \"creeep\"".to_string())
            .level(8)
            .create();

        let x_id = x.id;

        let y = Cryp::new()
            .named(&"lemongrass tea".to_string())
            .level(8)
            .create();

        let y_id = y.id;

        let mut game = Game::new();

        game
            .set_team_num(2)
            .set_team_size(1);

        let x_team_id = Uuid::new_v4();
        let mut x_team = Team::new(x_team_id);
        x_team
            .set_cryps(vec![x]);

        let y_team_id = Uuid::new_v4();
        let mut y_team = Team::new(y_team_id);
        y_team
            .set_cryps(vec![y]);

        game
            .add_team(x_team)
            .add_team(y_team);

        assert!(game.can_start());

        game.start();

        let x_attack_id = game.add_ability(x_team_id, x_id, y_team_id, AbilityKind::Attack);
        let y_attack_id = game.add_ability(y_team_id, y_id, x_team_id, AbilityKind::Attack);

        assert!(game.ability_phase_finished());

        game.targets_phase_start();

        println!("{:?}", game);

        game.add_target(x_team_id, x_id, y_attack_id);
        game.add_target(y_team_id, y_id, x_attack_id);

        assert!(game.target_phase_finished());

        game.damage_phase_start();

        assert!([Phase::Ability, Phase::Finish].contains(&game.phase));

        println!("{:?}", game);

        return;
    }
}