#!/bin/bash
# LTTng Trace Control bash completion
#

_lttng_complete_sessions() {
    local sessions
    if  ! _complete_as_root ; then
        sessions=$(for i in $(ls -d ~/.lttng/*/); do  basename $i; done)
        COMPREPLY=( $(compgen -W "${sessions}" -- $cur) )
    #else
        # Permission denied, what should we do ?
        # sessions=$(for i in $(ls -d ~root/.lttng/*/); do  basename $i; done)
        #COMPREPLY=( $(compgen -W "${sessions}" -- $cur) )
    fi
}

_lttng_create() {
    local create_opts
    create_opts="-h --help -o --output"
    
    case $prev in
    --output|-o)
        _filedir -d
        return
        ;;
    esac
    
    case $cur in
    -*)
        COMPREPLY=( $(compgen -W "${create_opts}" -- $cur) )
        return
        ;;
    esac
}

_lttng_start_stop() {
    local start_stop_opts
    start_stop_opts="-h --help"

    case $cur in
    -*)
        COMPREPLY=( $(compgen -W "${start_stop_opts}" -- $cur) )
        ;;
    *)
        _lttng_complete_sessions
        ;;
    esac
}

_lttng_opts() {
    local opts
    opts=$(lttng --dump-options)

    COMPREPLY=( $(compgen -W "${opts}" -- $cur) )
}

_lttng_commands() {
    COMPREPLY=( $(compgen -W "$commands" -- $cur) )
}

_lttng_before_command() {
    # Check if the previous word should alter the behavior
    case $prev in
    --group|-g)
        COMPREPLY=( $(compgen -g -- $cur) )
        return
        ;;
    esac

    case $cur in
    -*)
        # If the current word starts with a dash, complete with options
        _lttng_opts
        ;;
    *)
        # Otherwise complete with commands
        _lttng_commands
        ;;
    esac
}

_lttng_after_command() {
    case $command_found in
    "create")
        _lttng_create
        ;;
    "start"|"stop")
        _lttng_start_stop
        ;;
    esac
}

_lttng_is_command() {
    for command in $commands; do
        if [ "$1" == "$command" ]; then
            return 0
        fi
    done
    
    return 1
}

_lttng() {
    local cur prev commands command_found command_found_index
    
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"
    commands=$(lttng --dump-commands)
    
    command_found=""
    command_found_index=-1

    for (( i = 1 ; i < ${#COMP_WORDS[@]} ; i++ )); do
        _lttng_is_command ${COMP_WORDS[$i]}
        if [ $? -eq 0 ]; then
            command_found=${COMP_WORDS[$i]}
            command_found_index=$i
            break
        fi
        
    done
    
    if [ -n "$command_found" ] && [ "$COMP_CWORD" -gt "$command_found_index" ]; then
        _lttng_after_command
    else
        _lttng_before_command
    fi
}

complete -F _lttng lttng