#!/bin/sh
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | Copyright (C) 2017 OpenCFD Ltd.
#    \\/     M anipulation  |
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM.
#
#     OpenFOAM is free software: you can redistribute it and/or modify it
#     under the terms of the GNU General Public License as published by
#     the Free Software Foundation, either version 3 of the License, or
#     (at your option) any later version.
#
#     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
#     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
#     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
#     for more details.
#
#     You should have received a copy of the GNU General Public License
#     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
#
# Script
#     foamCreateBashCompletions
#
# Description
#     Create bash completions for OpenFOAM applications
#
#------------------------------------------------------------------------------
usage() {
    exec 1>&2
    while [ "$#" -ge 1 ]; do echo "$1"; shift; done
    cat<<USAGE

Usage: ${0##*/} [OPTION] [appName .. [appNameN]]
options:
  -d dir | -dir dir       Directory to process
  -u | -user              Add \$FOAM_USER_APPBIN to the search directories
  -head | -header         Generate header
  -h | -help              Print the usage

Create bash completions for OpenFOAM applications and write to stdout.
By default searches \$FOAM_APPBIN only.
Alternatively, scan the output from individual applications for single completion
commands (using the '_of_complete_' backend).

USAGE
    exit 1
}


#-------------------------------------------------------------------------------

searchDirs="$FOAM_APPBIN"
unset optHeader
while [ "$#" -gt 0 ]
do
    case "$1" in
        -h | -help)
            usage
            ;;
        -d | -dir)
            searchDirs="$2"
            [ -d $searchDirs ] || usage "directory not found '$searchDirs'"
            shift
            ;;
        -u | -user)
            searchDirs="$searchDirs $FOAM_USER_APPBIN"
            ;;
        -head | -header)
            optHeader=true
            ;;
        -*)
            usage "unknown option: '$1'"
            ;;
        *)
            break
            ;;
    esac
    shift
done

# No applications given, then always generate a header
if [ "$#" -eq 0 ]
then
    optHeader=true
fi

# Header requested or required
[ "$optHeader" = true ] && cat << HEADER
#----------------------------------*-sh-*--------------------------------------
# Bash completions for OpenFOAM applications
# Recreate with "${0##*/}"
#
# Formatted as "complete ... -F _of_APPNAME APPNAME

#
# Generic completion handler for OpenFOAM applications
# - arg1 = command-name
# - arg2 = current word
# - arg3 = previous word
# - arg4 = options with args
# - arg5 = options without args
#
unset -f _of_complete_ 2>/dev/null
_of_complete_()
{
    # Unused: local cmd=\$1
    local cur=\$2
    local prev=\$3
    local optsWithArgs="\$4 "   # Trailing space added for easier matching
    local opts="\$5 "

    case \${prev} in
    -help|-doc|-srcDoc)
        COMPREPLY=()
        ;;
    -case)
        COMPREPLY=(\$(compgen -d -- \${cur}))
        ;;
    -time)
        # Could use "foamListTimes -withZero", but still doesn't address ranges
        COMPREPLY=(\$(compgen -d -X '![-0-9]*' -- \${cur}))
        ;;
    -region)
        local list=\$(\ls -d system/*/ 2>/dev/null | sed -e 's#/\$##' -e 's#^.*/##')
        COMPREPLY=(\$(compgen -W "\$list" -- \${cur}))
        ;;
    -fileHandler)
        COMPREPLY=(\$(compgen -W "collated uncollated masterUncollated" -- \${cur}))
        ;;
    *Dict)
        # local dirs=\$(\ls -d s*/)
        # local files=\$(\ls -f | grep Dict)
        # COMPREPLY=(\$(compgen -W \"\$dirs \$files\" -- \${cur}))
        COMPREPLY=(\$(compgen -f -- \${cur}))
        ;;
    *)
        if [ "\${optsWithArgs/\${prev} /}" != "\${optsWithArgs}" ]
        then
            # Option with unknown type of arg - set to files.
            # Not always correct but can still navigate path if needed...
            COMPREPLY=(\$(compgen -f -- \${cur}))
        else
            # Catchall
            # - Present remaining options (not already seen in $COMP_LINE)
            opts=\$(
                for o in \${opts} \${optsWithArgs}
                do
                    [ "\${COMP_LINE/\$o/}" = "\${COMP_LINE}" ] && echo \$o
                done
            )
            COMPREPLY=(\$(compgen -W "\${opts}" -- \${cur}))
        fi
        ;;
    esac

    return 0
}

#------------------------------------------------------------------------------

HEADER

#-------------------------------------------------------------------------------

# Scans the output of the application -help to detect options with/without
# arguments.  Dispatch via _of_complete_
#
generateCompletion()
{
    local fullName="$1"
    local appName="${1##*/}"
    local appHelp

    [ -f "$fullName" -a -x "$fullName" ] || {
        echo "skip $fullName" 1>&2
        return 1
    }
    if [ "$appName" = "complete_" ]
    then
        echo "skip $appName ... reserved name?" 1>&2
        return 1
    fi

    appHelp=$($fullName -help) || {
        echo "error calling $fullName" 1>&2
        return 1
    }

    echo "    $appName" 1>&2

    # Options with args - as array
    local optsWithArgs=($(awk '/^ {0,4}-[a-z]/ && /</ {print $1}' <<< "$appHelp"))

    # Options without args - as array
    local opts=($(awk '/^ {0,4}-[a-z]/ && !/</ {print $1}' <<< "$appHelp"))

    # See bash(1) for some details. Completion functions are called with
    # arg1 = command-name, arg2 = current word, arg3 = previous word
    #
    # Append known option types and dispatch to _of_complete_
    cat << COMPLETION

# $appName
unset -f _of_${appName} 2>/dev/null
_of_${appName}() {
    _of_complete_ "\$@" \\
    "${optsWithArgs[@]}" \\
    "${opts[@]}"
} && complete -o filenames -F _of_${appName} $appName

COMPLETION
}
#------------------------------------------------------------------------------


if [ "$#" -eq 0 ]
then

    for dir in ${searchDirs}
    do
        if [ -d "$dir" ]
        then
            echo "Processing directory $dir" 1>&2
        else
            echo "No such directory: $dir" 1>&2
            continue
        fi

        # Sort with ignore-case
        set -- $(\ls $dir | sort -f)
        for appName
        do
            generateCompletion "$dir/$appName"
        done
    done

else

    for appName
    do
        if [ -f "$appName" -a -x "$appName" ]
        then
            generateCompletion "$appName"
        elif fullName=$(command -v $appName 2>/dev/null)
        then
            generateCompletion "$fullName"
        else
            echo "No application found: $appName" 1>&2
        fi
    done

fi


# Generate footer
[ "$optHeader" = true ] && cat << FOOTER

#------------------------------------------------------------------------------
FOOTER

#------------------------------------------------------------------------------