#!/usr/bin/env bash
# Copyright 2014 Vladimir Ivanov <ivvl82@gmail.com>
# Distributed under the terms of the GNU General Public License v2

REPO_DIR=

# Specify the tournament here
TOURNAMENT=

# Version information
VERSION="0.3"

# Firefox User Agent
FIREFOX_UA="Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Firefox/24.0"

argv0=${0##*/}

function usage {
    cat <<EOF
Store chess games played on lichess.org

Usage:
  $argv0 -t <num> [-u] [<url>]
  $argv0 -h
  $argv0 -v

  Put the script under the root directory of your repository or set
  inner variable REPO_DIR to it. If the tournament is not the last one
  (default), store its sub-directory in inner variable TOURNAMENT.

  The first form fills the results of chess games and stores its PGN
  files, assuming that all the games were played by the same pair of
  players on tour <num> of the tournament. The PGN files are sorted by
  their timestamps, unless '-u' is set. Each game should be available
  at the corresponding <url> (lichess.org).

  The second form shows this help output. The third form shows version
  information.

Options:
  -u            Don't sort games by their timestamps
EOF

    exit "${1:-0}"
}

function version {
    exec echo "${argv0}-${VERSION}"
}

function game_setup {
    : ${REPO_DIR:=`dirname "$0"`}

    # If no tournament given, set it to the last one
    if [[ -z $TOURNAMENT ]]; then
        local year_dir=$(ls -1 -d ${REPO_DIR}/[0-9][0-9][0-9][0-9]/ | tail -1)
        TOURNAMENT=$(ls -1 -d ${year_dir}[0-9]-*/ | tail -1 \
            | sed -E "s|${REPO_DIR}/(.*)/|\1|")
    fi

    # Configuration file for players
    ply_ini=${REPO_DIR}/${TOURNAMENT}/players.ini
    [[ -f $ply_ini ]] || die "File ${ply_ini} not found."
    # Pairs of players on the tour
    tour_info=${REPO_DIR}/${TOURNAMENT}/tours/${TOUR}/tour_info
    [[ -f $tour_info ]] || die "File ${tour_info} not found."
}

function game_tmp_pgns {
    TMP_PGN_FILES=
    # Don't sort just one game
    [[ $# == 1 ]] && SORT_GAMES=false

    for url in $@; do
        local pgn_template="pgn"
        [[ $url =~ ^(http://[^/]*)/([^/]*) ]]
        # Link to annotated game PGN
        local game_url=${BASH_REMATCH[1]}/game/export/${BASH_REMATCH[2]::8}.pgn

        # Append the timestamp of game for sorting
        if $SORT_GAMES; then
            local game_api=${BASH_REMATCH[1]}/api/game/${BASH_REMATCH[2]::8}
            local api_response=$(curl -q --fail --location --silent "$game_api")
            [[ -z $api_response ]] && die "Unreachable game API ${game_api}"
            local game_time=$(sed -En "s/.*\"timestamp\":([0-9]+).*/\1/p" <<< "$api_response")
            pgn_template+="-${game_time}"
        fi

        # Store PGN file in a temporal location
        local tmp_pgn=$(mktemp -t ${pgn_template}.XXXXXX)
        TMP_PGN_FILES+=" $tmp_pgn"
        trap "rm $TMP_PGN_FILES" EXIT
        wget -q -U "$FIREFOX_UA" -O $tmp_pgn "$game_url" \
            || die "Unreachable game PGN ${game_url}"
    done

    $SORT_GAMES && TMP_PGN_FILES=$(xargs -n1 <<< "$TMP_PGN_FILES" | sort | xargs)
}

function game_get_players {
    # Make an associative array from Lichess nicks to players' names
    declare -A NAMES=()
    game_assoc_names

    local ply_names=
    for pgn in $TMP_PGN_FILES; do
        # Extract players on Lichess
        local wt_lichess=$(sed -En "s/\[White \"([^\"]*)\"\]/\1/p" $pgn)
        local bk_lichess=$(sed -En "s/\[Black \"([^\"]*)\"\]/\1/p" $pgn)

        game_add_player $wt_lichess
        game_add_player $bk_lichess
    done

    # Select the names of two players
    players=( $(echo -en "$ply_names" | sort -u) )
    [[ ${#players[@]} == 2 ]] || die "Players of the games are not the same."
}

function game_assoc_names {
    game_parse_config
    local sections=$(grep -o "config_section_player[0-9]*" $tmp_ini)
    for sect in $sections; do
        eval $sect
        NAMES+=( [$lichess]=$name )
    done
}

function game_parse_config {
    # Temporary files
    tmp_ini=$(mktemp -t `basename $ply_ini`.XXXXXX)
    TMP_INI_FILES="${tmp_ini} ${tmp_ini}.prev"
    trap "rm $TMP_INI_FILES $TMP_PGN_FILES" EXIT

    # Copy player INI file to the temporary location
    # NOTE: an empty line is added to the file beginning in order to
    # match the only first occurrence for non-GNU sed
    echo > $tmp_ini
    cat "$ply_ini" >> $tmp_ini

    # Remove tabs or spaces around the `='
    sed -E -i.prev "s/[[:blank:]]*=[[:blank:]]*/=/" "$tmp_ini"

    # Transform section labels into function declaration
    sed -E -i.prev "1,/^\[.*\]/s/^\[([^]]*)\]/config_section_\1() {/" "$tmp_ini"
    sed -E -i.prev "s/^\[([^]]*)\]/}\\"$'\n'"config_section_\1() {/" "$tmp_ini"
    echo -e "\n}" >> $tmp_ini

    # Source the file
    source "$tmp_ini"
}

function game_add_player {
    local lichess_ply=$1
    local ply=${NAMES[$lichess_ply]}
    while [[ ! " ${NAMES[@]} " =~ \ $ply\  ]]; do
        echo "The list of players:"
        echo "${NAMES[@]}" | tr ' ' '\n' | sed "s/^/$(tput setaf 6)*$(tput sgr0) /"
        echo -n "Type the name of ${lichess_ply}> "
        read ply
    done
    ply_names+="${ply}\n"
}

function game_add_to_repo {
    local date_re="[0-9?]{2}\.[0-9?]{2}\.[0-9?]{4}"
    local correct=false length_max=0
    local white=${players[0]} black=${players[1]}
    # Change field separator to read a file line by line
    old_IFS=$IFS IFS=$'\n'
    # Check if the tour number is correct
    for line in $(cat "$tour_info"); do
        if [[ $line =~ ^(${date_re}\ +([^\ ]+)\ +-\ +([^\ ]+)) ]]; then
            local length=${#BASH_REMATCH[1]}
            local fst_ply=${BASH_REMATCH[2]} snd_ply=${BASH_REMATCH[3]}

            if [[ $fst_ply == $white && $snd_ply == $black ]]; then
                local length_rec=${#BASH_REMATCH[1]}
                correct=true
            fi

            if [[ $fst_ply == $black && $snd_ply == $white ]]; then
                local length_rec=${#BASH_REMATCH[1]}

                local answer
                echo -n "Approve game with wrong players' sides? (Y/n)> "
                read answer
                [[ $answer =~ ^(Y|y|Yes|yes)$ ]] || exit 1
                white=$fst_ply black=$snd_ply correct=true
            fi

            # Determine the maximal length of game records
            (( $length > $length_max )) && length_max=$length
        fi
    done
    IFS=$old_IFS

    if ! $correct; then
        die "Game '${white} vs. ${black}' not found in ${tour_info}."
    fi

    local pgn_date=$(sed -En "s/\[Date \"([^\"]*)\"\]/\1/p" "$tmp_pgn")
    local pgn_date=$(tr "." "-" <<< "$pgn_date")
    pgn_dir=${REPO_DIR}/${TOURNAMENT}/tours/${TOUR}/${pgn_date}-${white}-vs-${black}

    [[ -d $pgn_dir ]] && die "Directory ${pgn_dir} already exist."
    echo "Creating directory ${pgn_dir}..."
    mkdir -p "$pgn_dir"

    echo "Storing PGN file..."
    cp "$tmp_pgn" "${pgn_dir}/1.pgn"

    echo "Updating tour_info..."
    local game_date=${pgn_date:8:2}.${pgn_date:5:2}.${pgn_date::4}
    local result=$(sed -En "s/\[Result \"([^\"]*)\"\]/\1/p" $tmp_pgn)
    local spaces=$((length_max - length_rec + 1))
    local sep=$(printf "%${spaces}s" " ")

    # Change the representation of draw
    [[ $result == 1/2-1/2 ]] && result=1/2

    sed -E -i.orig \
        "s|${date_re}( +${white} +- +${black})|${game_date}\1${sep}${result}|" "$tour_info"
    rm "${tour_info}.orig"
}

function game_git_commit {
    (
        cd $REPO_DIR
        git add "${pgn_dir}/1.pgn" "$tour_info"
        git commit -m "Tour ${TOUR#0}: ${white} vs. ${black}."
        git push
    )
}

function die {
    echo "$@" >&2
    exit 1
}

function checkargs {
    [[ $OPTARG =~ ^[0-9]+$ ]] || die "Incorrect tour number."
    TOUR=$(printf "%02g" $OPTARG)
}

SORT_GAMES=true
while getopts t:uhv opt; do
    case $opt in
        t) checkargs        ;;
        u) SORT_GAMES=false ;;
        h) usage            ;;
        v) version          ;;
        *) usage 1          ;;
    esac
done

shift $(($OPTIND - 1))
# For now, tour number should be given explicitly
[[ -z $TOUR || $# == 0 ]] && usage 1

game_setup
(cd $REPO_DIR; git pull)        # update the repository
game_tmp_pgns $@
game_get_players
game_add_to_repo
game_git_commit

exit 0