tput terminfo basic color reference

term_colors.sh

set_color () {

    local arg2
    case $2 in
        bg|background)
        arg2=setb
        ;;
        *)
        arg2=setf
    esac

    case $1 in
    black|BLACK)
        $(tput $arg2 0)
        ;;
    blue|BLUE)
        $(tput $arg2 1)
        ;;
    green|GREEN)
        $(tput $arg2 2)
        ;;
    cyan|CYAN)
        $(tput $arg2 3)
        ;;
    red|RED)
        $(tput $arg2 4)
        ;;
    magenta|MAGENTA|magen)
        $(tput $arg2 5)
        ;;
    yellow|YELLOW|yellw)
        $(tput $arg2 6)
        ;;
    white|WHITE)
        $(tput $arg2 7)
        ;;
    *)
        $(tput sgr0)
        ;;
    esac
}

unix_terminal_color_reference.txt

The setaf/setab and setf/setb capabilities take a single numeric argument each.   
Argument  values  0-7  of  setaf/setab  are  portably defined as follows (the middle column is the symbolic #define available in the header for the curses or ncurses libraries). The terminal hardware is free to map these as it likes, but the RGB values indicate normal locations in color space.
        Color     #define           Value    RGB
        black     COLOR_BLACK       0        0, 0, 0
        red       COLOR_RED         1        max,0,0
        green     COLOR_GREEN       2        0,max,0
        yellow    COLOR_YELLOW      3        max,max,0
        blue      COLOR_BLUE        4        0,0,max
        magenta   COLOR_MAGENTA     5        max,0,max
        cyan      COLOR_CYAN        6        0,max,max
        white     COLOR_WHITE       7        max,max,max

The argument values of setf/setb historically correspond to a different mapping, i.e.,

        Color     #define           Value    RGB
        black     COLOR_BLACK       0        0, 0, 0
        blue      COLOR_BLUE        1        0,0,max
        green     COLOR_GREEN       2        0,max,0
        cyan      COLOR_CYAN        3        0,max,max
        red       COLOR_RED         4        max,0,0
        magenta   COLOR_MAGENTA     5        max,0,max
        yellow    COLOR_YELLOW      6        max,max,0
        white     COLOR_WHITE       7        max,max,max

It is important to not confuse the two sets of color capabilities; otherwise red/blue will be interchanged on the display.