#include "game.h"

#include "hand.h"

#include <boost/assign/list_of.hpp>
using boost::assign::list_of;

void Player::round_start(int w) {
	// Reset contents.
	hand.clear();
	open.clear();
	pond.clear();
	tenpai_indexes.clear();
	riichi = false;
	score = 25000;
	wind = w;
	won = 0;
	
	// Notify client of round start.
	client->round_start();
}

PlayerState Player::get_state() {
	Tilegroups h;
	h.push_back(hand);
	
	for(Sets::iterator it = open.begin(); it != open.end(); it++) {
		h.push_back(it->tiles);
	}
	
	PlayerState state = {h, pond, riichi, score, wind};
	return state;
}

PlayerState Player::get_state_filtered() {
	Tiles hand_filtered;
	for(int i = 0; i < hand.size(); i++) {
		hand_filtered.push_back(Tile::Back);
	}
	
	Tilegroups h;
	h.push_back(hand_filtered);
	
	for(Sets::iterator it = open.begin(); it != open.end(); it++) {
		h.push_back(it->tiles);
	}
	
	PlayerState state = {h, pond, riichi, score, wind};
	return state;
}

Actions Player::get_actions_draw() {
	Actions possible_actions;
	
	// Check if player can force a draw.
	// TODO: Implementation. (Low priority)
	
	// Check if player can tsumo.
	if(can_tsumo()) {
		possible_actions.push_back(Action(Action::Tsumo));
	}
	
	// Check if player can declare a concealed kan.
	Targets targets = can_kan();
	for(Targets::iterator it = targets.begin(); it != targets.end(); it++) {
		possible_actions.push_back(Action(Action::Kan, Action::Index, *it + 2));
	}
	
	// Check if player can extend an open pon.
	targets = can_kan_extend();
	for(Targets::iterator it = targets.begin(); it != targets.end(); it++) {
		possible_actions.push_back(Action(Action::Kan, Action::Group, *it));
	}
	
	if(!riichi) {
		// Check if player can riichi.
		if(can_riichi()) {
			possible_actions.push_back(Action(Action::Riichi));
		}
		
		// List all tiles that can be discarded.
		for(std::size_t i = 0; i < hand.size(); i++) {
			// Skip tiles already used to call kan.
			if(possible_actions.contains(Action(Action::Kan, Action::Index, i))) {
				continue;
			}
			
			possible_actions.push_back(Action(Action::Discard, Action::Index, i));
		}
	
	} else {
		if(tenpai_indexes) {
			for(List<int>::iterator it = tenpai_indexes.begin(); it != tenpai_indexes.end(); it++) {
				possible_actions.push_back(Action(Action::Discard, Action::Index, *it));
			}
			tenpai_indexes.clear();
		} else {
			// Only tile that can be discarded is the last drawn one.
			possible_actions.push_back(Action(Action::Discard, Action::Index, hand.size() - 1));
		}
	}
	
	return possible_actions;
}

Actions Player::get_actions_discard(Tile tile, PlayerNum discarder) {
	Actions possible_actions;
	
	if(!riichi) {
		// Check if tile can be called for a chi. Enumerate all combinations.
		if(discarder == 3) {
			Targets targets = can_chi(tile);
			if(!targets.empty()) {
				for(Targets::iterator it = targets.begin(); it != targets.end(); it++) {
					possible_actions.push_back(Action(Action::Chi, Action::Index, *it));
				}
			}
		}
		
		// Check if tile can be called for a pon.
		int target = can_pon(tile);
		if(target >= 0) {
			possible_actions.push_back(Action(Action::Pon, Action::Index, target + 1));
			
			// Check if tile can be called for a kan.
			if(can_kan(tile, target)) {
				possible_actions.push_back(Action(Action::Kan, Action::Index, target + 2));
			}
		}
	}
	
	// Check if tile can be ron-ed.
	if(can_ron(tile)) {
		possible_actions.push_back(Action(Action::Ron));
	}
	
	// If any action is possible, add option to pass.
	if(possible_actions) {
		possible_actions.push_back(Action::Pass);
	}
	
	return possible_actions;
}

bool Player::can_riichi() {
	if(open) {
		return false;
	}
	
	// Iterate over the hand, testing to remove each tile and see if it gives tenpai.
	for(Tiles::iterator it = hand.begin(); it != hand.end(); it++) {
		Tiles tiles = hand;
		tiles.del(it - hand.begin());
		tiles.sort();
		
		if(Hand::tenpai(tiles)) {
			tenpai_indexes.push_back(it - hand.begin());
		}
	}
	
	return bool(tenpai_indexes);
}

Player::Targets Player::can_chi(Tile tile) {
	Targets targets;
	
	Tile::Set set = tile.get_set();
	int num = tile.get_num();
	
	// Check if tile actually can be chi-ed.
	if(set == Tile::Honor) {
		return targets;
	}
	
	bool have_above = false;
	
	// Check if we have tile below.
	Tiles::iterator it = std::find(hand.begin(), hand.end(), Tile(set, num - 1));
	if(num > 1 && it != hand.end()) {
		
		// Check if we also have tile below tile below.
		Tiles::iterator it2 = std::find(hand.begin(), hand.end(), Tile(set, num - 2));
		if(num > 2 && it2 != hand.end()) {
			targets.push_back(it2 - hand.begin()); // (T-2 T-1 T)
		}
		
		// Check if we have tile above.
		it2 = std::find(hand.begin(), hand.end(), Tile(set, num + 1));
		if(num < 9 && it2 != hand.end()) {
			targets.push_back(it - hand.begin()); // (T-1 T T+1)
			have_above = true;
			it = it2;
		}
	}
	
	// Check if we have tile above.
	if(have_above || (it = std::find(hand.begin(), hand.end(), Tile(set, num + 1))) != hand.end()) {
		// Check if we have tile above tile above.
		Tiles::iterator it2 = std::find(hand.begin(), hand.end(), Tile(set, num + 2));
		if(num < 8 && it2 != hand.end()) {
			targets.push_back(it - hand.begin()); // (T T+1 T+2)
		}
	}
	
	return targets;
}

int Player::can_pon(Tile tile) {
	Tiles::iterator it = std::find(hand.begin(), hand.end(), tile);
	if(it + 1 < hand.end() && it[1] == tile) {
		return it - hand.begin();
	}
	
	return -1;
}

Player::Targets Player::can_kan() {
	Targets targets;
	
	for(Tiles::iterator it = hand.begin(); it != hand.end(); it++) {
		Tiles::iterator it_s = it;
		int i = 1;
		do {
			it_s = std::find(it_s + 1, hand.end(), *it);
		} while(it_s != hand.end() && i++);
		if(i >= 4) {
			targets.push_back(it - hand.begin());
		}
	}
	
	return targets;
}

Player::Targets Player::can_kan_extend() {
	Targets targets;
	
	for(Sets::iterator it = open.begin(); it != open.end(); it++) {
		if(it->type == Set::Pon && hand.contains(it->tiles.front())) {
			targets.push_back(it - open.begin() + 1);
		}
	}
	
	return targets;
}

bool Player::can_kan(Tile tile, int target) {
	if(std::size_t(target + 2) < hand.size() && hand[target + 2] == tile) {
		return true;
	}
	return false;
}

bool Player::can_tsumo() {
	Tiles tiles = hand;
	tiles.sort();
	return Hand::agari(tiles);
}

bool Player::can_ron(Tile tile) {
	// Check furiten.
	if(pond.contains(tile)) {
		return false;
	}
	// TODO: Furiten due to unclaimed discard in last go-around.
	
	Tiles tiles = hand;
	tiles.push_back(tile);
	tiles.sort();
	return Hand::agari(tiles);
}

void Player::draw(Tile tile) {
	hand.push_back(tile);
}

void Player::discard(int target) {
	Tile tile = hand[target];
	hand.erase(hand.begin() + target);
	hand.sort();
	pond.push_back(tile);
}

Tile Player::last_discard() {
	return pond.back();
}

Tile Player::claim() {
	Tile& t = pond.back();
	t.invisible = true;
	return t;
}

void Player::declare_riichi() {
	riichi = true;
}

void Player::make_chi(Tile tile, int target) {
	Tiles chi;
	
	tile.rotated = true;
	chi.push_back(tile);
	
	Tile::Set set = tile.get_set();
	int num = tile.get_num();
	
	Tiles::iterator it = hand.begin();
	
	switch(hand[target].get_num() - num) {
		case -2:
			it = std::find(it, hand.end(), Tile(set, num - 2));
			chi.push_back(*it);
			it = hand.erase(it);
		
		case -1:
			it = std::find(it, hand.end(), Tile(set, num - 1));
			chi.push_back(*it);
			it = hand.erase(it);
			
		case 1:
			if(chi.size() == 3) {
				break;
			}
			
			it = std::find(it, hand.end(), Tile(set, num + 1));
			chi.push_back(*it);
			it = hand.erase(it);
			
			if(chi.size() == 3) {
				break;
			}
			
			it = std::find(it, hand.end(), Tile(set, num + 2));
			chi.push_back(*it);
			hand.erase(it);
	}
	
	open.push_back(Set(Set::Chi, chi, true));
}

void Player::make_pon(Tile tile, int target, PlayerNum discarder) {
	Tiles pon;
	
	tile.rotated = true;
	
	if(discarder == 3) {
		pon.push_back(tile);
	}
	
	pon.push_back(hand[target]);
	hand.del(target);
	
	if(discarder == 2) {
		pon.push_back(tile);
	}
	
	pon.push_back(hand[target]);
	hand.del(target);
	
	if(discarder == 1) {
		pon.push_back(tile);
	}
	
	open.push_back(Set(Set::Pon, pon, true));
}

void Player::make_kan(Tile tile, int target, PlayerNum discarder) {
	Tiles kan;
	
	tile.rotated = true;
	
	if(discarder == 3) {
		kan.push_back(tile);
	}
	
	kan.push_back(hand[target]);
	hand.del(target);
	
	if(discarder == 2) {
		kan.push_back(tile);
	}
	
	kan.push_back(hand[target]);
	hand.del(target);
	
	kan.push_back(hand[target]);
	hand.del(target);
	
	if(discarder == 1) {
		kan.push_back(tile);
	}
	
	open.push_back(Set(Set::Kan, kan, true));
}

void Player::make_kan(int target) {
	Tiles kan;
	
	Tiles::iterator it = hand.begin() + target;
	Tile t = *it;
	kan.push_back(Tile::Back);
	it = hand.erase(it);
	
	it = std::find(it, hand.end(), t);
	kan.push_back(*it);
	it = hand.erase(it);
	
	it = std::find(it, hand.end(), t);
	kan.push_back(*it);
	it = hand.erase(it);
	
	it = std::find(it, hand.end(), t);
	kan.push_back(Tile::Back);
	hand.erase(it);
	
	open.push_back(Set(Set::Kan, kan, false));
}

void Player::make_kan_extend(int target) {
	Set& set = open[target - 1];
	
	Tiles::iterator it = std::find(hand.begin(), hand.end(), set.tiles.front());
	Tile t = *it;
	hand.erase(it);
	
	t.rotated = true;
	
	for(it = set.tiles.begin(); it != set.tiles.end(); it++) {
		if(it->rotated) {
			set.tiles.insert(it + 1, t);
			break;
		}
	}
	
	set.type = Set::Kan;
}

void Player::declare_ron(Tile tile) {
	hand.push_back(tile);
	// TODO: Mark winning tile.
	hand.sort();
	
	List<Sets> hands = Hand::get_breakdowns(hand);
	
	Sets hand = hands.front();
	hand.insert(hand.end(), open.begin(), open.end());
	
	List<std::pair<std::string, int> > han;
	
	Score score = calculate_score(hand, han, false);
	
	won = true;
	won_han = han;
	won_value = score;
}

void Player::declare_tsumo() {
	// TODO: Mark winning tile.
	hand.sort();
	
	List<Sets> hands = Hand::get_breakdowns(hand);
	
	Sets hand = hands.front();
	hand.insert(hand.end(), open.begin(), open.end());
	
	List<std::pair<std::string, int> > han;
	
	Score score = calculate_score(hand, han, true);
	
	won = true;
	won_han = han;
	won_value = score;
}

Score Player::calculate_score(const Sets& hand, List<std::pair<std::string, int> >& han, bool tsumo) {
	Tiles yakuhai = list_of(Tile::Chun)(Tile::Hatsu)(Tile::Haku); // TODO: Add seat and prevalent wind.
	Tiles dora; // TODO: Fill this.
	Tiles uradora; // TODO: Fill this.
	
	Score score(0, 20, 0); // Always 20 fu for winning.
	
	// Check riichi.
	if(riichi) {
		score.yaku += 1;
		han.push_back(std::make_pair("Riichi", 1));
		// TODO: Check ippatsu.
	}
	
	// Check menzen tsumo.
	if(tsumo && !open) {
		score.yaku += 1;
		han.push_back(std::make_pair("Menzen tsumo", 1));
	}
	
	bool possible_tanyao = true;
	bool possible_toitoi = true;
	int dora_n = 0;
	int uradora_n = 0;
	int akadora_n = 0;
	
	for(Sets::const_iterator set = hand.begin(); set != hand.end(); set++) {
		switch(set->type) {
			case Set::Pair:
				// Check for pair-related fu.
				score.fu += 2 * yakuhai.count(set->tiles.front());
				
				break;
			
			case Set::Chi:
				// Toitoi can't contain chi.
				possible_toitoi = false;
				break;
			
			case Set::Pon:
			case Set::Kan:
				// Calculate fu.
				score.fu += 2 << (!set->open + !set->tiles.front().is_simple() + 2 * (set->type == Set::Kan));
				
				// Check yakuhai.
				if(int yakuhai_n = yakuhai.count(set->tiles.front())) {
					score.yaku += yakuhai_n;
					han.push_back(std::make_pair("Yakuhai", yakuhai_n)); // TODO: Specify which tile.
				}
				
				break;
		}
		
		for(Tiles::const_iterator tile = set->tiles.begin(); tile != set->tiles.end(); tile++) {
			// Check tanyao.
			if(!tile->is_simple()) {
				possible_tanyao = false;
			}
			
			// Check dora.
			dora_n += dora.count(*tile);
			
			// Check uradora.
			uradora_n += uradora.count(*tile);
			
			// Check akadora.
			if(tile->red) {
				akadora_n += 1;
			}
		}
	}
	
	// Check tanyao.
	if(possible_tanyao) {
		score.yaku += 1;
		han.push_back(std::make_pair("Tanyao", 1));
	}
	
	// Check toitoi.
	if(possible_toitoi) {
		score.yaku += 2;
		han.push_back(std::make_pair("Toitoi", 2));
	}
	
	// Check pinfu.
	if(score.fu == 20) {
		if(open) {
			score.fu += 2;
		} else {
			score.yaku += 1;
			han.push_back(std::make_pair("Pinfu", 1));
		}
	} else if(tsumo) {
		score.fu += 2;
	}
	
	// Check fu for ron.
	if(!tsumo && !open) {
		// 10 fu for ron.
		score.fu += 10;
	}
	
	// Check dora.
	if(dora_n) {
		score.dora += dora_n;
		han.push_back(std::make_pair("Dora", dora_n));
	}
	
	// Check uradora.
	if(uradora_n) {
		score.dora += uradora_n;
		han.push_back(std::make_pair("Uradora", uradora_n));
	}
	
	// Check akadora.
	if(akadora_n) {
		score.dora += akadora_n;
		han.push_back(std::make_pair("Akadora", akadora_n));
	}
	
	return score;
}