// #[allow(dead_code, unused)]

// vigyazz6! autoplayer

//

// This is a program automagically playing a card game called "Vigyazz6!".

//

// The rules are rather simple, but I'mrather lazy to reprint it in detail,

// so it'll be brief.

// 

// The code is based on a deck of 104 numbered cards, all of them having

// a face `value` and punishment `points` (the less the better).

// There are 2 to 10 players (but above 8 the code shall be modified to

// deal less cards), and the game has 5 rows of maximum 5 cards on the

// table. 

// All players throw cards at once, and they are put in the row with 

// closest less value; if there is none, they have to pick and take

// any row. When a row is full (5) they have to take the row and their

// card starts a new row head.

// When players are out of cards the least points collected wins.

//

// Important: I do not use `unsafe` code, this is all tightly controlled.

//

/// We use panic in several places where the code shall not go. 

use core::panic;

/// `VecDeque` is a Vec which can be pushed/popped at both ends

/// `time::Instant` is used to measure running time.

/// `cmp::Reverse` used for reverse sorting.

use std::{collections::VecDeque, time::Instant, cmp::Reverse};

/// We use this `pretty_env_logger` as a logging framework.

extern crate pretty_env_logger;

#[macro_use] extern crate log;

// I import structures from my module files to use here.

use crate::{deck::Deck, player::{Player, PlayerCard}, table::Table};

// Here we read the files and "get to know" what's in them. This isn't including, only scanning.

mod deck;

mod table;

mod player;

mod card;

mod row;

// We play this many game rounds. You want to keep this under 3 for any debug level above "warnings".

const GAME_ROUNDS: i32 = 100_000;

fn main() {

    // Env variable makes the logger to log more or less:

    // RUST_LOG=debug cargo run

    pretty_env_logger::init();

    info!("Program starting."); // info level logging

    game();

    info!("End of run.");

}

/*** Game ****/

/// `GameStat` structure collects global statistics about the run.

struct GameStat {

    game_count: i64,

    shuffle_count: i64,

    start_time: Instant, // use start_time.elapsed().as_nanos() or .as_secs()

}

/// Play all the game rounds.

fn game() {

    // Whole game statistics stored here

    let mut stats = GameStat { game_count:0, shuffle_count: 0, start_time: Instant::now() };

    // Create the game deck with all the card (ordered). Open box. Remove shrink wrap. :-)

    let mut deck = Deck::new();

    // Create the players (up to 8 w/o changing the hand cards)

    let player_names = vec![ "peter", "moni", "icbalint", "orsi", "topi", "kgb", "zsu", "csilla" ];

    // Iterate on player names, create Player struct from them and collect them into a Vec'tor.

    // (On the borrow level we don't consume the player_names vector [using `iter()` instead of `into_iter()`].)

    let mut players: Vec<Player> = player_names.iter().map( |n| Player::new(n.to_string()) ).collect();

    // We use this often, so take it now.

    let player_count = players.len(); // = <number of players> - 1

    // Start playing - GAME_ROUNDS rounds.

    for cnt_game in 1..=GAME_ROUNDS {

        debug!("Game round {} starts", cnt_game); // debug level logging

        // Shuffle the deck (using various methods)

        deck.shuffle();

        stats.shuffle_count += 1;

        stats.game_count += 1;

        // dealing 10 cards for each player

        debug!("Dealing.");

        for _i in 1..=10 {

            for player in 0 .. player_count {

                players[player].get_card( deck.pop().expect("Deck is empty while dealing to players") );

            }

        }

        // we need 5 cards from deck to build the rows

        debug!("Building the rows.");

        let mut cards = VecDeque::new();

        // This is another way to write "for _ in (1..=5) { ... }"

        (1..=5).for_each(|_| {

            cards.push_back( deck.pop().expect("deck empty before starting the game") );

        });

        trace!("We pushed 5 cards to rows: {:?}\n", cards);

        // Create the Table (contains the Deck, the Rows (with 5 starting `cards`) and occasional cards thrown by Players)

        let mut table = Table::new(cards);

/*      debug!("Table: {:?}\n", table);

        debug!("Players: {:?}\n", players);

        debug!("Deck: {:?}\n", deck);

 */        

        debug!("We have the table ready: {:?}", table);

        // playing one game, players taking turns

        debug!("Players start taking turns");

        // Since players have 10 cards dealt we have exactly 10 turns.

        for turn in 1..=10 {

            debug!("Turn {}!", turn);

            trace!("The table: {:?}", table);

            // Everyone puts a card "face down" (Rust promised not to peek).

            // If I used the `players.for_each()` form I would hit the borrow checker:

            // `players` would be repeatedly borrowed mutable and program wouldn't compile.

            for player in 0 .. player_count {

                // get a card from the player

                let player_id: i32 = player.try_into().unwrap();    // convert `usize` array index into `i32` [that was an unnecessary hassle: in fact I should rewrite this using usize everywhere]

                let topcard = players[player].throw_card();         // If Player [module] was smart this would be a chosen card, but it would need player

                                                                    // not just brains but possibility to peek at the rows. This wasn't in the plan, so 

                                                                    // we just take the top card in hand.

                // put it on the table ("turned face down")

                table.lay_player_card( topcard, player_id );        // We actually move the card variable with its ownership everywhere, so no &refs.

            }

            // Process cards on the Table.

            debug!("The Table process the throws.");

            // Sort the cards by `value` the players have thrown.

            table.sort_cards();

            // Pick them one by one, from smallest to larger ones

            while table.has_player_cards() {

                let smallest: PlayerCard = table.get_smallest_player_card(); // I just wrote the PlayerCard type to show; Rust is smart enough to know.

                trace!("Take smallest card {:?}", &smallest);

                // Find the row with the closest smallest card, or None if smaller than any row head.

                let closest_row = table.get_closest_row(&smallest); // That is an Option<usize>.

                trace!("Choose closest row: {:?}", closest_row);

                match closest_row {

                    Some(rowid) => {

                        // We have to put it at the end of `rowid`.

                        debug!("Putting down card into row {}", rowid);

                        let player_id: usize = smallest.player_id.try_into().unwrap(); // By "just" indexing `players` (by `player_id`) I have avoided borrowing it and get into trouble later.

                        // Try to put the card to the end of the row, or collect full row first

                        let overflow = table.put_card_into_row(smallest, rowid); // And this is Option<VecDeque<Card>>.

                        if let Some(cards) = overflow {

                            // Row is full, we got pile ("bust")

                            debug!("Row is busted, {} collects", players[player_id].get_name());    

                            // Player gets pile, thrown card was put into row head

                            players[ player_id ].give_pile( cards );

                        }

                    },

                    None => {

                        // Card too small, need to pick any row to take!

                        let player_id: usize = smallest.player_id.try_into().unwrap(); // We _directly_ access `PlayerCard.player_id` structure member, because borrow checker wasn't helping my mental hygiene.

                        debug!("Too small from {}, picking row", players[player_id].get_name());

                        // Pick any row to take

                        let rowid = players[ player_id ].pick_row_for_small_card(table.peek_rows(), &smallest.card);

                        trace!("Picked row {}", rowid);

                        // take the row cards ("bust")

                        let cards = table.take_row(rowid);

                        trace!("Took cards: {:?}", cards);

                        // and give them to the player who owns the card

                        players[ player_id ].give_pile( cards );

                        // put new card in the row

                        let overflow = table.put_card_into_row(smallest, rowid);

                        if let Some(_) = overflow {

                            // If this fires then I have fucked something up. :-)

                            panic!("Player took whole row and it's already full");

                        }

                    }

                }

            }

        }

        // end of round

        info!("Round finished, len is {} ??sec", stats.start_time.elapsed().as_micros());

        debug!("End of round, counting and collecting back piles");

        // We collect the winner(s) and their score here

        let mut winners: Vec<usize> = Vec::new();

        let mut winscore: i32 = i32::MAX-1; // Getting facy here about "larger than any valid value".

        for i in 0..player_count {

            info!("Player {} has {} points", players[i].get_name(), players[i].get_points());

            if players[i].get_points() < winscore  {

                trace!("New winner {} with score {}", players[i].get_name(), players[i].get_points());

                winners.clear();

                winners.push(i);

                winscore = players[i].get_points();

            } else if players[i].get_points() == winscore {

                trace!("New co-winner {} with score {}", players[i].get_name(), players[i].get_points());

                winners.push(i);

            }

            trace!("The list of winners is {:?}", winners);

            // get pile from Player

            let cards = players[i].get_pile();

            // and give it back to the Deck

            deck.push_cards(cards);

            // close Player round and update stats

            players[i].close_round();

        }

        // collect remaining Cards from Table

        deck.push_cards( table.collect_rows() );

        trace!("Shall have full deck now, len {}", deck.len());

        // This is a Vec of `player_id`s, i is a &ref

        for i in winners.iter() {

            players[*i].inc_wins(); // Increment win count of &Vec<usize> player_id

        }

        // Collect the names of the winners.

        let mut finals = Vec::new();

        for i in winners {

            finals.push( players[i].get_name() );

        }

        info!("The winner(s): {:?}", &finals);

    }

    // Do the type conversions _very_ visibly. `as_micros()` results `u128`

    let elapsed_micro: f64 = stats.start_time.elapsed().as_micros() as f64;

    // and `GAME_ROUNDS` is `i32`. We'll use `elapsed_micro/game_rounds` later.

    let game_rounds: f64 = GAME_ROUNDS.into();

    // ???which is same as the slightly uglier:

    let _res: f64 = stats.start_time.elapsed().as_micros() as f64 / <i32 as Into<f64>>::into(GAME_ROUNDS);

    println!("Totals (game time {} ??s, or {} s; {} ??s/game), {} games played ({} shuffles):", 

        stats.start_time.elapsed().as_micros(), 

        stats.start_time.elapsed().as_secs(),

        elapsed_micro / game_rounds, 

        stats.game_count,

        stats.shuffle_count,

    );

    // players.sort_by( |a, b| a.total_point.partial_cmp(&b.total_point).unwrap() );    // ASC points

    // players.sort_by( |a, b| b.wins.partial_cmp(&a.wins).unwrap() );                  // DESC wins

    players.sort_by_cached_key( |x| Reverse(x.get_wins()) );                            // DESC wins (caching is just for the show); using std::cmp::Reverse

    // Print out totals

    for i in 0..players.len() {

        let p = &players[i]; // the rest looks simpler by using this. (Seems to confuse rust-analyzer in codium though.)

        println!("Player {} has wins {}, score {} (busted {} times)", 

            p.get_name(), 

            p.get_wins(), 

            p.get_total_points(), 

            p.get_rows_busted());

    }

}

#[cfg(test)]

mod tests {

    use std::collections::VecDeque;

    use rand::Rng;

    use crate::{card::Card, player::{Player, PlayerCard}, row::Row, table::Table};

    #[test]

    fn card_values() {

        let card_values = vec![1,2,5,10,33,55,77];

        let card_points = vec![1,1,2,3, 5, 7, 5];

        for i in 1 .. card_values.len() {

            let c = Card::new( card_values[i] );

            let p = c.points;

            assert!(p == card_points[i], "card={} card points={} i={} expected point={}", card_values[i], p, i, card_points[i]);

        }

    }

    #[test]

    fn player_take_pile() {

        // create a player

        let mut p = Player::new("bob".to_string());

        // create a pile

        let mut pile = VecDeque::new();

        let mut refpile = VecDeque::new();

        for i in 5..10 {

            let c = Card::new(i);

            pile.push_back(c);

            let c = Card::new(i);

            refpile.push_back(c);

        }

        // give the pile to player

        p.give_pile(pile);

        assert!( p.get_rows_busted() == 1 );

        // get back the pile from player

        // p = p.gimme_pile();

        let pile = p.get_pile();

        // the pile we got shall be same as the pile we gave

        // this check is O(n^2), doesn't matter for less than 100 items

        assert_eq!( pile, refpile );

        assert!( pile.iter().all( |item| refpile.contains(item)) );

        let mut pile = VecDeque::new();

        for i in 4..=9 {

            let c = Card::new(i);

            pile.push_back(c);

        }

        p.give_pile(pile);

        assert!( p.get_rows_busted() == 2 );

    }

    #[test]

    fn row_push() {

        let mut row = Row::new();

        let mut refcard = VecDeque::new();   // reference vec to check

        for i in 1..=7 {

            let cval = i+5;

            let card = Card::new(cval);

            // push a card into the row

            if let Some(cards) = row.push_or_collect(card) {

                // got the overflow

                println!("Got overflow row at {}!", i);

                assert!( i == 6, "Overflow at wrong position: {} != 6", i );

                // we need to get the proper vec

                assert!( cards.iter().all( |item| refcard.contains(item) ), "Got cards {:?}", cards ); 

            } else {

                println!("push success {}", i);

            }

            // remember the correct vec for checking

            let card = Card::new(cval);

            refcard.push_back(card);

            // check card value

            assert!( row.last_card_value() == cval, "Last card value mismatch: got {} vs expected {}", row.last_card_value(), cval );

        }

        assert!( row.len() == 2, "Row contains wrong amount of cards: {}", row.len() );

    }

    #[test]

    fn sort_cards() {

        let mut cards: VecDeque<Card> = VecDeque::new();

        let mut rng = rand::thread_rng();