use uuid::Uuid;
use rand::prelude::*;
use serde_cbor::{from_slice, to_vec};

use postgres::transaction::Transaction;

use failure::Error;
use failure::err_msg;

use account::Account;
use rpc::{CrypSpawnParams, CrypLearnParams, CrypForgetParams};
use skill::{Skill, Cooldown, Effect, Cast, Immunity, Disable};
use game::{Log};

#[derive(Debug,Clone,Copy,PartialEq,Serialize,Deserialize)]
pub struct CrypSkill {
    pub skill: Skill,
    pub self_targeting: bool,
    pub cd: Cooldown,
}

impl CrypSkill {
    pub fn new(skill: Skill) -> CrypSkill {
        CrypSkill {
          skill,
          self_targeting: skill.self_targeting(),
          cd: skill.cd(),
        }
    }
}

#[derive(Debug,Clone,PartialEq,Serialize,Deserialize)]
pub struct CrypEffect {
    pub effect: Effect,
    pub duration: u8,
    pub tick: Option<Cast>,
}

#[derive(Debug,Clone,Copy,PartialEq,Serialize,Deserialize)]
pub enum Stat {
    Str,
    Agi,
    Int,
    PhysDmg,
    SpellDmg,
    Hp,
    Stamina,
}

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

impl CrypStat {
    pub fn set(&mut self, v: u64) -> &CrypStat {
        self.base = v;
        self
    }

    pub fn reduce(&mut self, amt: u64) -> &mut CrypStat {
        self.base = self.base.saturating_sub(amt);
        self
    }

    pub fn increase(&mut self, amt: u64) -> &mut CrypStat {
        self.base = self.base.saturating_add(amt);
        self
    }

}

#[derive(Debug,Clone,Serialize,Deserialize)]
pub struct Cryp {
    pub id: Uuid,
    pub account: Uuid,
    pub phys_dmg: CrypStat,
    pub spell_dmg: CrypStat,
    pub stamina: CrypStat,
    pub hp: CrypStat,
    pub xp: u64,
    pub lvl: u8,
    pub skills: Vec<CrypSkill>,
    pub effects: Vec<CrypEffect>,
    pub name: String,
}

fn check_lvl(lvl: u8) -> u8 {
    if lvl > 64 { return 64; }
    return lvl;
}

impl Cryp {
    pub fn new() -> Cryp {
        let id = Uuid::new_v4();
        return Cryp {
            id,
            account: id,
            phys_dmg: CrypStat { base: 0, stat: Stat::PhysDmg },
            spell_dmg: CrypStat { base: 0, stat: Stat::SpellDmg },
            stamina: CrypStat { base: 0, stat: Stat::Stamina },
            hp: CrypStat { base: 0, stat: Stat::Hp },
            lvl: 0,
            xp: 0,
            skills: vec![CrypSkill::new(Skill::Attack)],
            effects: vec![],
            name: String::new()
        };
    }

    pub fn named(mut self, name: &String) -> Cryp {
        self.name = name.clone();
        self
    }

    pub fn set_account(mut self, account: Uuid) -> Cryp {
        self.account = account;
        self
    }

    pub fn level(mut self, lvl: u8) -> Cryp {
        self.lvl = check_lvl(lvl);
        self
    }

    pub fn learn(mut self, s: Skill) -> Cryp {
        self.skills.push(CrypSkill::new(s));
        self
    }

    pub fn forget(mut self, skill: Skill) -> Result<Cryp, Error> {
        match self.skills.iter().position(|s| s.skill == skill) {
            Some(i) => {
                self.skills.remove(i);
                return Ok(self);
            },
            None => Err(format_err!("{:?} does not know {:?}", self.name, skill)),
        }
    }

    pub fn add_xp(mut self) -> Cryp {
        self.xp = self.xp.saturating_add(1);
        if self.xp.is_power_of_two() {
            return self.level_up();
        }
        self
    }

    pub fn level_up(mut self) -> Cryp {
        self.lvl = self.lvl.saturating_add(1);
        self.create()
    }

    pub fn create(mut self) -> Cryp {
        let mut rng = thread_rng();
        let max = match self.lvl == 64 {
            true => u64::max_value(),
            false => 2_u64.pow(self.lvl.saturating_sub(1).into()),
        };

        let min = match self.lvl == 1 {
            true => 2_u64,
            false => 2_u64.pow(self.lvl.saturating_sub(2).into()),
        };

        self.xp = max;

        self.phys_dmg.set(rng.gen_range(min, max));
        self.spell_dmg.set(rng.gen_range(min, max));
        self.stamina.set(rng.gen_range(min, max));
        self.hp.set(self.stamina.base);

        self
    }

    pub fn is_ko(&self) -> bool {
        self.hp.base == 0
    }

    pub fn immune(&self, skill: Skill) -> Immunity {
        if self.is_ko() {
           return Immunity { immune: true, effects: vec![Effect::Ko]};
        }

        let immunities = self.effects.iter()
            .filter(|e| e.effect.immune(skill))
            .map(|e| e.effect)
            .collect::<Vec<Effect>>();

        if immunities.len() > 0 {
            return Immunity { immune: true, effects: immunities};
        }

        return Immunity { immune: false, effects: vec![]};
    }

    pub fn disabled(&self, skill: Skill) -> Disable {
        if self.is_ko() {
           return Disable { disabled: true, effects: vec![Effect::Ko]};
        }

        let disables = self.effects.iter()
            .filter(|e| e.effect.disables_skill(skill))
            .map(|e| e.effect)
            .collect::<Vec<Effect>>();

        if disables.len() > 0 {
            return Disable { disabled: true, effects: disables};
        }

        return Disable { disabled: false, effects: vec![]};
    }


    pub fn is_stunned(&self) -> bool {
        self.effects.iter().any(|s| s.effect == Effect::Stun)
    }

    pub fn available_skills(&self) -> Vec<&CrypSkill> {
        self.skills.iter()
            .filter(|s| s.cd.is_none())
            .filter(|s| !self.disabled(s.skill).disabled)
            .collect()
    }

    pub fn knows(&self, skill: Skill) -> bool {
        self.skills.iter().any(|s| s.skill == skill)
    }

    pub fn skill_on_cd(&self, skill: Skill) -> Option<&CrypSkill> {
        self.skills.iter().find(|s| s.skill == skill && s.cd.is_some())
    }

    pub fn skill_set_cd(&mut self, skill: Skill) -> &mut Cryp {
        let i = self.skills.iter().position(|s| s.skill == skill).unwrap();
        self.skills.remove(i);
        self.skills.push(CrypSkill::new(skill));

        self
    }

    pub fn reduce_cooldowns(&mut self) -> &mut Cryp {
        for skill in self.skills.iter_mut() {
            // if used cooldown
            if let Some(cd) = skill.skill.cd() {
                // if the cd is 1 it becomes none
                if cd == 1 {
                    // println!("{:?} is now off cd", skill.skill);
                    skill.cd = None;
                    continue;
                }

                // otherwise decrement it
                skill.cd = Some(cd.saturating_sub(1));
            }
        }

        self
    }

    pub fn reduce_effect_durations(&mut self, log: &mut Log) -> &mut Cryp {
        self.effects = self.effects.clone().into_iter().filter_map(|mut effect| {

            effect.duration = effect.duration.saturating_sub(1);

            if effect.duration == 0 {
                return None;
            }

            // println!("reduced effect {:?}", effect);
            return Some(effect);
        }).collect::<Vec<CrypEffect>>();

        self
    }

    pub fn rez(&mut self) -> &mut Cryp {
        self.hp.set(self.stamina.base);
        self
    }

    // Stats
    pub fn phys_dmg(&self) -> u64 {
        let phys_dmg_mods = self.effects.iter()
            .filter(|e| e.effect.modifications().contains(&Stat::PhysDmg))
            .map(|cryp_effect| cryp_effect.effect)
            .collect::<Vec<Effect>>();
        // println!("{:?} phys_dmg mods : {:?}", self.name, phys_dmg_mods);
        let modified_phys_dmg = phys_dmg_mods.iter().fold(self.phys_dmg.base, |acc, m| m.apply(acc));
        // println!("{:?} phys_dmg : {:?}", self.name, modified_phys_dmg);
        return modified_phys_dmg;
    }

    pub fn spell_dmg(&self) -> u64 {
        let spell_dmg_mods = self.effects.iter()
            .filter(|e| e.effect.modifications().contains(&Stat::SpellDmg))
            .map(|cryp_effect| cryp_effect.effect)
            .collect::<Vec<Effect>>();
        // println!("{:?} spell_dmg mods : {:?}", self.name, spell_dmg_mods);
        let modified_spell_dmg = spell_dmg_mods.iter().fold(self.spell_dmg.base, |acc, m| m.apply(acc));
        // println!("{:?} spell_dmg : {:?}", self.name, modified_spell_dmg);
        return modified_spell_dmg;
    }

    pub fn hp(&self) -> u64 {
        self.hp.base
    }

    pub fn stamina(&self) -> u64 {
        self.stamina.base
    }

    // Stat modifications
    pub fn heal(&mut self, amount: u64) -> (u64, u64) {
        let current_hp = self.hp();
        let new_hp = *[
            self.hp().saturating_add(amount),
            self.stamina()
        ].iter().min().unwrap();

        self.hp.set(new_hp);

        let healing = new_hp - current_hp;
        let overhealing = amount - healing;
        return (healing, overhealing);
    }

    pub fn deal_phys_dmg(&mut self, amount: u64) -> (u64, u64) {
        self.hp.reduce(amount);
        // println!("{:?} dealt {:?} phys dmg", self.name, amount);
        return (amount, 0);
    }

    pub fn deal_spell_dmg(&mut self, amount: u64) -> (u64, u64) {
        self.hp.reduce(amount);
        return (amount, 0);
    }

}

pub fn cryp_get(tx: &mut Transaction, id: Uuid, account_id: Uuid) -> Result<Cryp, Error> {
    let query = "
        SELECT data
        FROM cryps
        WHERE id = $1
        AND account = $2;
    ";

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

    let result = result.iter().next().ok_or(format_err!("cryp {:} not found", id))?;
    let cryp_bytes: Vec<u8> = result.get(0);
    let cryp = from_slice::<Cryp>(&cryp_bytes)?;

    return Ok(cryp);
}

pub fn cryp_spawn(params: CrypSpawnParams, tx: &mut Transaction, account: &Account) -> Result<Cryp, Error> {
    let cryp = Cryp::new()
        .named(&params.name)
        .level(10)
        .set_account(account.id)
        .create();

    let cryp_bytes = to_vec(&cryp)?;

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

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

    let _returned = result.iter().next().ok_or(err_msg("no row returned"))?;

    println!("{:?} spawned cryp {:}", account.id, cryp.id);

    return Ok(cryp);
}

pub fn cryp_learn(params: CrypLearnParams, tx: &mut Transaction, account: &Account) -> Result<Cryp, Error> {
    let mut cryp = cryp_get(tx, params.id, account.id)?;

    // done here because i teach them a tonne of skills for tests
    let max_skills = 4;
    if cryp.skills.len() >= max_skills {
        return Err(format_err!("cryp at max skills ({:?})", max_skills));
    }

    cryp = cryp.learn(params.skill);
    return cryp_write(cryp, tx);
}

pub fn cryp_forget(params: CrypForgetParams, tx: &mut Transaction, account: &Account) -> Result<Cryp, Error> {
    let mut cryp = cryp_get(tx, params.id, account.id)?;
    cryp = cryp.forget(params.skill)?;
    return cryp_write(cryp, tx);
}

pub fn cryp_write(cryp: Cryp, tx: &mut Transaction) -> Result<Cryp, Error> {
    let cryp_bytes = to_vec(&cryp)?;

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

    let result = tx
        .query(query, &[&cryp_bytes, &cryp.id])?;

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

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

    return Ok(cryp);
}

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

  #[test]
  fn create_cryp_test() {
        let max_level = Cryp::new()
            .named(&"hatchling".to_string())
            .level(64)
            // .learn(Skill::Stoney)
            .create();

        assert_eq!(max_level.lvl, 64);
        return;
    }
}


  // pub fn assign_str(&mut self, opp: &Cryp, plr_t: &mut Turn, opp_t: &Turn) -> &mut Cryp {
  //   // let final_str = opp_t.phys_dmg.result.saturating_sub(plr_t.agi.result);
  //   // let blocked = opp_t.phys_dmg.result.saturating_sub(final_str);

  //   let final_str = opp_t.phys_dmg.result & !plr_t.agi.result;
  //   let blocked = opp_t.phys_dmg.result & plr_t.agi.result;

  //   plr_t.log.push(format!("{:064b}   <- attacking roll {:?}", opp_t.phys_dmg.result, opp_t.phys_dmg.result));
  //   // plr_t.log.push(format!("{:064b}   <- blocking roll {:?}", plr_t.agi.result, plr_t.agi.result));
  //   plr_t.log.push(format!("{:064b}   <- final str {:?} ({:?} blocked)", final_str, final_str, blocked));

  //   self.hp.reduce(final_str);

  //   plr_t.log.push(format!("{:?} deals {:?} str to {:?} ({:?} blocked / {:?} hp remaining)"
  //     ,opp.name
  //     ,final_str
  //     ,self.name
  //     ,blocked
  //     ,self.hp.base));

  //   plr_t.log.push(format!(""));
  //   self
  // }

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

      //   let mut roll = Roll { kind: self.kind, base, result: base };

      //   log.push(format!("{:?}", self.kind));
      //   log.push(format!("{:064b}   <- base roll", base));

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

      //   // finally combine with CrypStat
      //   log.push(format!("{:064b}   <- finalised", roll.result));
      //   roll.result = roll.result & self.base;

      //   log.push(format!("{:064b} & <- attribute roll", self.base));
      //   log.push(format!("{:064b} = {:?}", roll.result, roll.result));
      //   log.push(format!(""));

      //   return roll;
      // }