#!/bin/bash

##################################################
# Mount file                                     #
# - /etc/my.cnf                                  #
# Mount dir                                      #
# - LOG_DIR                                      #
# - DATA_DIR                                     #
# - BINLOG_DIR                                   #
##################################################

set -euo pipefail
export LANG=en_US.UTF-8
trap Quit EXIT

PIDS=
GOT_SIGTERM=
LOG_DIR='/var/log/mysql'
DATA_DIR='/var/lib/mysql'
BINLOG_DIR='/var/lib/mysql-bin'
SOCK_FILE='/run/mysqld/mysqld.sock'
PID_FILE='/run/mysqld/mysqld.pid'
INIT_FLAG=

function Print {
    local file=/dev/null
    [ '-f' = "$1" ] && file=$2 && shift && shift
    date +"[%F %T] $*" | tee -a $file
}

function Quit {
    Print killing mysqld ...
    mysqladmin shutdown || true
    while :; do
        pkill -f mysqld && Print killing mysqld ... || break
        sleep 1
    done
    Print Container stopped.
    test -n "$GOT_SIGTERM"
}

function Init {
    rm -f ${SOCK_FILE}* ${PID_FILE}
    chown -R mysql:mysql $LOG_DIR $BINLOG_DIR $DATA_DIR
    if [ ! -d "$DATA_DIR/mysql" ]; then
        Print Initing mysql db files ...
        mysqld_pre_systemd
        INIT_FLAG=1
    fi
}

function ImportInitSql {
    local sql_file= sql_files=
    mysql -e "CREATE USER docker@localhost IDENTIFIED BY 'China_19\$(10)!'"
    mysql -e "GRANT RELOAD,SHUTDOWN ON *.* TO docker@localhost"
    if sql_files="$(ls $LOG_DIR/init_sql/*.sql 2>/dev/null)"; then
        Print Importing the sql files ...
        for sql_file in $sql_files; do
             Print Importing $sql_file ...
             mysql < $sql_file
        done
        Print Imported all sql files successfully.
    fi
}

function SideCar {
    local day= last_day=$(date +%d)
    while sleep 8; do
        day=$(date +%d) \
            && [ "$day" != "$last_day" ] \
            && last_day=$day \
            && find $LOG_DIR -type f -name "*.log" \
                | xargs -I ^ mv -f ^ ^.$(date +%F -d yesterday) \
            && mysqladmin flush-logs
    done
}

function StartProc {
    Print Starting mysql ...
    mysqld -u mysql &
    PIDS="$PIDS $!"
    while sleep 1; do
        [ -e $SOCK_FILE ] && break || echo -n .
        [ ! -e /proc/$! ] && echo && Print unexpected error! && exit
    done
    echo
    [ -z "$INIT_FLAG" ] || ImportInitSql
    SideCar &
    PIDS="$PIDS $!"
    Print MySQL is ready for connections.
}

function Main {
    local pid=
    Init
    StartProc
    trap "GOT_SIGTERM=1; Print Got SIGTERM ..." SIGTERM
    while [ -z "$GOT_SIGTERM" ] && sleep 2; do
        for pid in $PIDS; do
            [ ! -e /proc/$pid ] && Print Unexpected error! && exit
        done
    done
}

# Start here
Main