function! taskwarrior#data#get_uuid(...)
    let line = a:0 == 0 ? '.' : a:1
    let vol = taskwarrior#data#get_value_by_column(line, 'uuid')
    let vol = vol =~ '[0-9a-f]\{8}\(-[0-9a-f]\{4}\)\{3}-[0-9a-f]\{12}' ?
                \ vol : taskwarrior#data#get_value_by_column(line, 'id')
    return vol =~ '^\s*-*\s*$' ? '' : vol
endfunction

function! taskwarrior#data#get_args(...)
    if a:0 == 0
        return
    elseif a:0 == 1
        return taskwarrior#data#get_args(a:1, g:task_default_prompt)
    endif
    let arg = ' '
    for key in a:2
        let default = a:1 == 'modify' ?
                    \ taskwarrior#data#get_value_by_column('.', key)
                    \ : ''
        let temp = shellescape(input(key.":", default), 1)
        if key == 'description'
            let arg .= ' '.temp
        elseif temp !~ '^[ \t]*$' || a:1 == 'modify'
            let arg .= ' '.key.':'.temp
        endif
    endfor
    echom arg
    return arg
endfunction

function! taskwarrior#data#get_value_by_column(line, column, ...)
    if a:line == 1 || (a:line == '.' && line('.') == 1)
        return ''
    endif
    if a:column == 'id' || a:column == 'uuid' || exists('a:1')
        let index = match(b:task_report_columns, '^'.a:column.'.*')
        return taskwarrior#data#get_value_by_index(a:line, index(b:task_report_columns, a:column))
    else
        let dict = taskwarrior#data#get_query()
        let val = get(dict, a:column, '')
        if type(val) == type('')
            return val
        elseif type(val) == type([])
            return join(val, ' ')
        else
            return string(val)
        endif
    endif
endfunction

function! taskwarrior#data#get_value_by_index(line, index)
    if exists('b:task_columns[a:index]')
        return substitute(getline(a:line)[b:task_columns[a:index]:b:task_columns[a:index+1]-1], '\(\s*$\|^\s*\)', '',  'g')
    endif
    return ''
endfunction

function! taskwarrior#data#current_index()
    let i = 0
    while  i < len(b:task_columns) && virtcol('.') >= b:task_columns[i]
        let i += 1
    endwhile
    return i-1
endfunction

function! taskwarrior#data#current_column()
    return matchstr(b:task_report_columns[taskwarrior#data#current_index()], '^\w\+')
endfunction

function! taskwarrior#data#get_stats(method)
    let dict = {}
    if a:method != 'current'
        let stat = split(system('task '.a:method.' stats'), '\n')
    else
        let uuid = taskwarrior#data#get_uuid()
        let stat = split(system('task '.taskwarrior#data#get_uuid().' stats'), '\n')
        if uuid == '' || len(stat) < 5
            return {}
        endif
    endif
    for line in stat[2:-1]
        if line !~ '^\W*$'
            let dict[split(line, '\s\s')[0]] = substitute(split(line, '\s\s')[-1], '^\s*', '', '')
        endif
    endfor
    return dict
endfunction

function! taskwarrior#data#get_query(...)
    let uuid = get(a:, 1, taskwarrior#data#get_uuid())
    if uuid == ''
        return {}
    endif
    let obj = webapi#json#decode(substitute(system(
                \ 'task rc.verbose=off '.uuid.' export'),
                \ '\nConfiguration.*', '', ''))
    return type(obj) == 3 ? obj[0] : obj
endfunction

function! taskwarrior#data#global_stats()
    let dict = taskwarrior#data#get_stats(b:filter)
    return [
                \ get(dict, 'Pending', 0),
                \ get(dict, 'Completed', 0),
                \ get(taskwarrior#data#get_stats(''), 'Pending', 0)
                \ ]
endfunction

function! taskwarrior#data#category()
    let dict           = {}
    let dict.Pending   = []
    let dict.Waiting   = []
    let dict.Recurring = []
    let dict.Completed = []
    for i in range(2, line('$'))
        let uuid = taskwarrior#data#get_uuid(i)
        if uuid == ''
            continue
        endif
        let subdict = taskwarrior#data#get_stats(uuid)
        if subdict.Pending == '1'
            let dict.Pending += [i]
        elseif subdict.Waiting == '1'
            let dict.Waiting += [i]
        elseif subdict.Recurring == '1'
            let dict.Recurring += [i]
        elseif subdict.Completed == '1'
            let dict.Completed += [i]
        endif
    endfor
    return dict
endfunction