view

#!/bin/bash

# Stop Verbose lines, thanks to Mark Harrison
TODOTXT_VERBOSE=0

# Get action
action=$1
shift

# Get option
option=$1;
shift

# Get rest of them
term="$@"

function usage() {
    echo "  $(basename $0) [OPTION] [TERM]"
    echo ""
    echo "    Show todo items containing TERM, grouped by OPTION, and displayed in"
    echo "    priority order. If no TERM provided, displays entire todo.txt."
    echo ""
    echo "    Usage"
    echo "      \$ todo.sh $(basename $0) [OPTION] [TERM]"
    echo ""
    echo "    Options"
    echo "      project           Show todo items group by project"
    echo "      context           Show todo items group by context"
    echo "      date              Show todo items group by date"
    echo "      nodate            Show todo items group by date without date"
    echo "      past              Show todo items group by date from today to past"
    echo "      future            Show todo items group by date from today to future"
    echo "      today             Show todo items group by date only today"
    echo "      yesterday         Show todo items group by date from today to yesterday"
    echo "      tomorrow          Show todo items group by date from today to tomorrow"
    echo "      ?length           Show todo items group by date from today to ?length"
    echo "                        ? could be signed(+-) or unsigned numbers."
    echo "                        Length could be (days|weeks|months|years)"
    echo ""
    echo "    Examples"
    echo "      \$ todo.sh $(basename $0) project          # Show todo items grouped by project"
    echo "      \$ todo.sh $(basename $0) project @context # Show todo items grouped by project and filtered by @context"
    echo "      \$ todo.sh $(basename $0) context          # Show todo items grouped by context"
    echo "      \$ todo.sh $(basename $0) date +project    # Show todo items grouped by date and filtered by +project"
    echo "      \$ todo.sh $(basename $0) -3days           # Show todo items grouped by date from today to 3days before today"
    echo "      \$ todo.sh $(basename $0) 4weeks           # Show todo items grouped by date from today to 4weeks after today"
    echo ""
    exit
}

function project_view() {
    # Show projects in alphabetical order and todo items in priority order
    echo "=====  Projects  ====="
    echo ""

    # Find all projects and sort
    PROJECTS=$(grep -o '[^  ]*+[^  ]\+' "$TODO_FILE" | grep '^+' | sort -u | sed 's/^+//g')

    # For each project show header and the list of todo items
    for project in $PROJECTS; do
        # Use core _list function, does numbering and colouring for us
        PROJECT_LIST=$(_list "$TODO_FILE" "+$project\b" "$term" | sed 's/\(^+\|\ *+\)[a-zA-Z0-9\{._\-\}]*\ */ /g')
        if [[ -n "${PROJECT_LIST}" ]]; then
            echo "---  $project  ---"
            echo "${PROJECT_LIST}"
            echo ""
        fi
    done

    # Show todo items not associated to a project
    PROJECT_LIST=$(_list "$TODO_FILE" "$term" | grep -v "+\w")
    if  [[ -n "${PROJECT_LIST}" ]]; then
        echo "---  Items without project  ---"
        echo "${PROJECT_LIST}"
    fi
}

function context_view() {
    # Show contexts in alphabetical order and todo items in priority order
    echo "=====  Contexts  ====="
    echo ""

    # Find all contexts and sort
    CONTEXTS=$(grep -o '[^  ]*@[^  ]\+' "$TODO_FILE" | grep '^@' | sort -u | sed 's/@//g')

    # For each context show header and the list of todo items
    for context in $CONTEXTS ; do
        # Use core _list function, does numbering and colouring for us
        CONTEXT_LIST=$(_list "$TODO_FILE" "@$context\b" "$term" | sed 's/(^@|\ *@)[^[:cntrl:] ]\ */ /g')
        if [[ -n "${CONTEXT_LIST}" ]]; then
            echo "---  $context  ---"
            echo "${CONTEXT_LIST}"
            echo ""
        fi
    done

    # Show todo items not associated to a context
    CONTEXT_LIST=$(_list "$TODO_FILE" "$term" | grep -v "@[^ ]*\ *")
    if [[ -n "${CONTEXT_LIST}" ]]; then
        echo "---  Items without context  ---"
        echo "${CONTEXT_LIST}"
    fi
}

function date_view() {
    #  Show dates in alphabetical order and todo items in priority order
    echo "=====  Dates  ====="
    echo ""

    #  Find all dates and sort
    DATES=$(grep -o '[^  ]*t:[^  ]\+' "$TODO_FILE" | grep '^t:' | sort -u | sed 's/^t://g')

    #  Get option
    option=$1

    #  Get today
    today=$(date -d $(date +%Y-%m-%d) +%s)

    #  For each date show header and the list of todo items
    for date in $DATES ; do
        # Check it is a valid date or not
        date_check $option $today $date
        show="$?"
        if [[ $show -eq 0 ]]; then
            # If it is not a valid date, just do nothing
            continue
        fi

        #  Use core _list function, does numbering and colouring for us
        DATE_LIST=$(_list "$TODO_FILE" "t:$date" "$term" | sed 's/\(^t:\|\ *t:\)[0-9-]*\ */ /g')
        if [ -n "${DATE_LIST}" ]; then
            echo  "---  $date  ---"
            echo  "${DATE_LIST}"
            echo  ""
        fi
    done

    #  Show todo items not associated to a date
    re="^(date|nodate)$"
    if [[ "$option" =~ $re ]]; then
        DATE_LIST=$(_list "$TODO_FILE" "$term" | grep -v "t:[0-9-]*")
        if [ -n "${DATE_LIST}" ]; then
            echo "---  Items without date  ---"
            echo "${DATE_LIST}"
        fi
    fi
}

function date_check() {
    # Assign variables
    threshold=$1
    today=$2
    _date=$(date -d "$3" +%s)

    # Check if the date is valid or not
    # return:
    #   1: If the date is valid
    #   0: If the date is invalid
    case $threshold in
    'future')
        if [[ "$_date" -ge "$today" ]]; then
            return 1
        fi
        ;;
    'past')
        if [[ "$_date" -le "$today" ]]; then
            return 1
        fi
        ;;
    'nodate')
        return 0
        ;;
    'date')
        return 1
        ;;
    *)
        if [[ "$threshold" -eq "$today" ]]; then
            if [[ "$_date" -eq "$today" ]]; then
                return 1
            fi
        elif [[ "$threshold" -gt "$today" ]]; then
            if [[ ( "$_date" -ge "$today" ) && ( "$_date" -le "$threshold" ) ]]; then
                return 1
            fi
        elif [[ "$threshold" -lt "$today" ]]; then
            if [[ ( "$_date" -le "$today" ) && ( "$_date" -ge "$threshold" ) ]]; then
                return 1
            fi
        fi
        ;;
    esac

    return 0
}

# Validate the input options
re="^(help|project|context|date|nodate|future|past|today|tomorrow|yesterday|([+-][0-9]+|[0-9]+)(days|weeks|months|years))$"
if [[ "$option" =~ $re ]]; then
    case $option in
    'help')
        usage
        ;;
    'project')
        project_view
        ;;
    'context')
        context_view
        ;;
    *)
        re="^(date|nodate|future|past)$"
        if [[ ! ( "$option" =~ $re ) ]]; then
            option=$(date -d $(date -d $option +%Y-%m-%d) +%s)
        fi

        date_view $option
        ;;
    esac
else
    echo "Error: Unrecognized option \"$option\"."
    echo "Try \"todo.sh view help\" to get more information."
fi