# hledger command line processing
#
# Quick guide to terms used here:
#
# - flag: generally a synonym for option. Or sometimes, just the first
#   part of an option: a hyphen followed by a letter (short flag) or a
#   word (long flag).
#
# - option: a command modifier. An option consists of a short flag, a
#   long flag, or both, and possibly an optional or required value.
#   Each option has some effect on program execution, and is described
#   in the command line help.
#
# - argument:
#   - raw command line arguments: everything following the program
#     name on the command line, ie what is returned by getArgs
#   - parsed arguments: all raw command line arguments that are not
#     options (flags or values).
#   - (sub)command arguments: all parsed arguments except the first
#     (which is the subcommand's name)
#
# - RawOpts: the command, options and arguments as parsed by cmdargs,
#   as an assocation list. Eg:
#   [("command","register"),("args","a"),("debug",""),("help","")]
#
# - CliOpts: the command, options and arguments from cmdargs, plus
#   additional cleanup, in a more convenient data structure used
#   throughout the hledger CLI code.
#
# - command:
#   - command line, shell command: what you type in the shell/terminal window to start a program
#   - hledger command, subcommand: one of hledger's several modes of operation,
#     usually selected by the first command-line argument that isn't an option.
#     Commands are listed in the general command line help. There are two kinds:
#     - internal commands: built in to the main hledger executable
#     - external commands, or add-ons: any other hledger-* executables in the users's PATH
#
# Description of existing/expected behaviour as of 2013/9/16:
#
# - general usage is hledger [COMMAND] [OPTIONS] [ARGS]
#
# - commands are internal (built in to the main hledger executable) or external (any hledger-* executables found in the PATH)
# - some internal commands have aliases, which are displayed in the general help
# - there are also a few hidden internal commands
# - COMMAND is an exact command or alias name, or any unique prefix of one (eg reg for register)
# - when COMMAND is a non-unique prefix, matching commands will be listed, including hidden ones (eg hledger c)
# - an unrecognised command shows an error and gives non-zero exit status
#
# - usually the command must come first, followed by options and arguments in any order
# - a few options may also go before the command: -f, --rules-file, --alias, --help, --version, --debug.
# - option flags may be written in full or as a unique prefix, eg --rules for --rules-file
# - if the command is external, options and arguments after the command are handled by that executable, not hledger
#
# - the --help flag has highest priority
# - --help before the command, or no command, shows general help, including available commands
# - --help after an internal command shows command-specific help, including command and general flags
# - there is no built-in "help" command

# version 

# 1. --version shows version
hledgerdev --version
>>> /^hledger [0-9]/
>>>=0

# 2. --version also works after a command, if it's internal
hledgerdev balance --version
>>> /^hledger [0-9]/
>>>=0

# help

# 3. with no command, show general help
hledgerdev
>>> /^hledger \[COMMAND\]/
>>>=0

# 4. no-command help still works if there are flags, at least the common ones
hledgerdev -fsomefile
>>> /^hledger \[COMMAND\]/
>>>=0

# 5. and also with a space between flag and value
hledgerdev -f somefile
>>> /^hledger \[COMMAND\]/
>>>=0

# 6. with --help, and possibly other common flags present, show general help
hledgerdev --help --version -f /dev/null
>>> /^hledger \[COMMAND\]/
>>>=0

# 7. with --help before COMMAND, show general help
hledgerdev --help balance --cost
>>> /^hledger \[COMMAND\]/
>>>=0

# 8. with --help after command, show command help
hledgerdev balance --help
>>> /^balance \[OPTIONS\]/
>>>=0

# 9. should work with deprecated commands too
hledgerdev convert --help
>>>
>>>2 /no longer needed/
>>>=1

# 10. with an unrecognised command, give general help and non-zero exit status
hledgerdev nosuchcommand
>>>
>>>2 /not recognized/
>>>=1

# flag positions

# 11. most flags can not go before command
hledgerdev --daily register
>>>
>>>2 /Unknown flag: --daily/
>>>=1

# 12. help and input flags can go before command
hledgerdev -f /dev/null --alias somealiases --rules-file -? -h --help --version --debug register --daily
>>> /^hledger \[COMMAND\]/
>>>=0

# 13. or after it, and spaces in options are optional
hledgerdev register -f/dev/null --alias=somealiases --rules-file -? -h --help --version --debug --daily
>>> /^register \[OPTIONS\]/
>>>=0

# 14. flags after and add-command are handled by the add-on
# needs updating
#hledgerdev accountnames.hs --help
#>>> /^assets$/
#>>>=0