tagged release 0.6.4

[parrot.git] / languages / tcl / library / msgcat / msgcat.tcl

# msgcat.tcl --
#
#       This file defines various procedures which implement a
#       message catalog facility for Tcl programs.  It should be
#       loaded with the command "package require msgcat".
#
# Copyright (c) 1998-2000 by Ajuba Solutions.
# Copyright (c) 1998 by Mark Harrison.
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
# 
# RCS: @(#) $Id$

package require Tcl 8.5
# When the version number changes, be sure to update the pkgIndex.tcl file,
# and the installation directory in the Makefiles.
package provide msgcat 1.4.2

namespace eval msgcat {
    namespace export mc mcload mclocale mcmax mcmset mcpreferences mcset \
            mcunknown

    # Records the current locale as passed to mclocale
    variable Locale ""

    # Records the list of locales to search
    variable Loclist {}

    # Records the mapping between source strings and translated strings.  The
    # dict key is of the form "<locale> <namespace> <src>", where locale and
    # namespace should be themselves dict values and the value is
    # the translated string.
    variable Msgs [dict create]

    # Map of language codes used in Windows registry to those of ISO-639
    if { $::tcl_platform(platform) eq "windows" } {
        variable WinRegToISO639 [dict create  {*}{
            01 ar 0401 ar_SA 0801 ar_IQ 0c01 ar_EG 1001 ar_LY 1401 ar_DZ
                  1801 ar_MA 1c01 ar_TN 2001 ar_OM 2401 ar_YE 2801 ar_SY
                  2c01 ar_JO 3001 ar_LB 3401 ar_KW 3801 ar_AE 3c01 ar_BH
                  4001 ar_QA
            02 bg 0402 bg_BG
            03 ca 0403 ca_ES
            04 zh 0404 zh_TW 0804 zh_CN 0c04 zh_HK 1004 zh_SG 1404 zh_MO
            05 cs 0405 cs_CZ
            06 da 0406 da_DK
            07 de 0407 de_DE 0807 de_CH 0c07 de_AT 1007 de_LU 1407 de_LI
            08 el 0408 el_GR
            09 en 0409 en_US 0809 en_GB 0c09 en_AU 1009 en_CA 1409 en_NZ
                  1809 en_IE 1c09 en_ZA 2009 en_JM 2409 en_GD 2809 en_BZ
                  2c09 en_TT 3009 en_ZW 3409 en_PH
            0a es 040a es_ES 080a es_MX 0c0a es_ES@modern 100a es_GT 140a es_CR
                  180a es_PA 1c0a es_DO 200a es_VE 240a es_CO 280a es_PE
                  2c0a es_AR 300a es_EC 340a es_CL 380a es_UY 3c0a es_PY
                  400a es_BO 440a es_SV 480a es_HN 4c0a es_NI 500a es_PR
            0b fi 040b fi_FI
            0c fr 040c fr_FR 080c fr_BE 0c0c fr_CA 100c fr_CH 140c fr_LU
                  180c fr_MC
            0d he 040d he_IL
            0e hu 040e hu_HU
            0f is 040f is_IS
            10 it 0410 it_IT 0810 it_CH
            11 ja 0411 ja_JP
            12 ko 0412 ko_KR
            13 nl 0413 nl_NL 0813 nl_BE
            14 no 0414 no_NO 0814 nn_NO
            15 pl 0415 pl_PL
            16 pt 0416 pt_BR 0816 pt_PT
            17 rm 0417 rm_CH
            18 ro 0418 ro_RO
            19 ru
            1a hr 041a hr_HR 081a sr_YU 0c1a sr_YU@cyrillic
            1b sk 041b sk_SK
            1c sq 041c sq_AL
            1d sv 041d sv_SE 081d sv_FI
            1e th 041e th_TH
            1f tr 041f tr_TR
            20 ur 0420 ur_PK 0820 ur_IN
            21 id 0421 id_ID
            22 uk 0422 uk_UA
            23 be 0423 be_BY
            24 sl 0424 sl_SI
            25 et 0425 et_EE
            26 lv 0426 lv_LV
            27 lt 0427 lt_LT
            28 tg 0428 tg_TJ
            29 fa 0429 fa_IR
            2a vi 042a vi_VN
            2b hy 042b hy_AM
            2c az 042c az_AZ@latin 082c az_AZ@cyrillic
            2d eu
            2e wen 042e wen_DE
            2f mk 042f mk_MK
            30 bnt 0430 bnt_TZ
            31 ts 0431 ts_ZA
            33 ven 0433 ven_ZA
            34 xh 0434 xh_ZA
            35 zu 0435 zu_ZA
            36 af 0436 af_ZA
            37 ka 0437 ka_GE
            38 fo 0438 fo_FO
            39 hi 0439 hi_IN
            3a mt 043a mt_MT
            3b se 043b se_NO
            043c gd_UK 083c ga_IE
            3d yi 043d yi_IL
            3e ms 043e ms_MY 083e ms_BN
            3f kk 043f kk_KZ
            40 ky 0440 ky_KG
            41 sw 0441 sw_KE
            42 tk 0442 tk_TM
            43 uz 0443 uz_UZ@latin 0843 uz_UZ@cyrillic
            44 tt 0444 tt_RU
            45 bn 0445 bn_IN
            46 pa 0446 pa_IN
            47 gu 0447 gu_IN
            48 or 0448 or_IN
            49 ta
            4a te 044a te_IN
            4b kn 044b kn_IN
            4c ml 044c ml_IN
            4d as 044d as_IN
            4e mr 044e mr_IN
            4f sa 044f sa_IN
            50 mn
            51 bo 0451 bo_CN
            52 cy 0452 cy_GB
            53 km 0453 km_KH
            54 lo 0454 lo_LA
            55 my 0455 my_MM
            56 gl 0456 gl_ES
            57 kok 0457 kok_IN
            58 mni 0458 mni_IN
            59 sd
            5a syr 045a syr_TR
            5b si 045b si_LK
            5c chr 045c chr_US
            5d iu 045d iu_CA
            5e am 045e am_ET
            5f ber 045f ber_MA
            60 ks 0460 ks_PK 0860 ks_IN
            61 ne 0461 ne_NP 0861 ne_IN
            62 fy 0462 fy_NL
            63 ps
            64 tl 0464 tl_PH
            65 div 0465 div_MV
            66 bin 0466 bin_NG
            67 ful 0467 ful_NG
            68 ha 0468 ha_NG
            69 nic 0469 nic_NG
            6a yo 046a yo_NG
            70 ibo 0470 ibo_NG
            71 kau 0471 kau_NG
            72 om 0472 om_ET
            73 ti 0473 ti_ET
            74 gn 0474 gn_PY
            75 cpe 0475 cpe_US
            76 la 0476 la_VA
            77 so 0477 so_SO
            78 sit 0478 sit_CN
            79 pap 0479 pap_AN
        }]
    }
}

# msgcat::mc --
#
#       Find the translation for the given string based on the current
#       locale setting. Check the local namespace first, then look in each
#       parent namespace until the source is found.  If additional args are
#       specified, use the format command to work them into the traslated
#       string.
#
# Arguments:
#       src     The string to translate.
#       args    Args to pass to the format command
#
# Results:
#       Returns the translated string.  Propagates errors thrown by the 
#       format command.

proc msgcat::mc {src args} {
    # Check for the src in each namespace starting from the local and
    # ending in the global.

    variable Msgs
    variable Loclist
    variable Locale

    set ns [uplevel 1 [list ::namespace current]]
    
    while {$ns != ""} {
        foreach loc $Loclist {
            if {[dict exists $Msgs $loc $ns $src]} {
                if {[llength $args] == 0} {
                    return [dict get $Msgs $loc $ns $src]
                } else {
                    return [format [dict get $Msgs $loc $ns $src] {*}$args]
                }
            }
        }
        set ns [namespace parent $ns]
    }
    # we have not found the translation
    return [uplevel 1 [list [namespace origin mcunknown] \
            $Locale $src {*}$args]]
}

# msgcat::mclocale --
#
#       Query or set the current locale.
#
# Arguments:
#       newLocale       (Optional) The new locale string. Locale strings
#                       should be composed of one or more sublocale parts
#                       separated by underscores (e.g. en_US).
#
# Results:
#       Returns the current locale.

proc msgcat::mclocale {args} {
    variable Loclist
    variable Locale
    set len [llength $args]

    if {$len > 1} {
        return -code error "wrong # args: should be\
                \"[lindex [info level 0] 0] ?newLocale?\""
    }

    if {$len == 1} {
        set newLocale [lindex $args 0]
        if {$newLocale ne [file tail $newLocale]} {
            return -code error "invalid newLocale value \"$newLocale\":\
                    could be path to unsafe code."
        }
        set Locale [string tolower $newLocale]
        set Loclist {}
        set word ""
        foreach part [split $Locale _] {
            set word [string trim "${word}_${part}" _]
            if {$word ne [lindex $Loclist 0]} {
                set Loclist [linsert $Loclist 0 $word]
            }
        }
        lappend Loclist {}
        set Locale [lindex $Loclist 0]
    }
    return $Locale
}

# msgcat::mcpreferences --
#
#       Fetch the list of locales used to look up strings, ordered from
#       most preferred to least preferred.
#
# Arguments:
#       None.
#
# Results:
#       Returns an ordered list of the locales preferred by the user.

proc msgcat::mcpreferences {} {
    variable Loclist
    return $Loclist
}

# msgcat::mcload --
#
#       Attempt to load message catalogs for each locale in the
#       preference list from the specified directory.
#
# Arguments:
#       langdir         The directory to search.
#
# Results:
#       Returns the number of message catalogs that were loaded.

proc msgcat::mcload {langdir} {
    set x 0
    foreach p [mcpreferences] {
        if { $p eq {} } {
            set p ROOT
        }
        set langfile [file join $langdir $p.msg]
        if {[file exists $langfile]} {
            incr x
            uplevel 1 [list ::source -encoding utf-8 $langfile]
        }
    }
    return $x
}

# msgcat::mcset --
#
#       Set the translation for a given string in a specified locale.
#
# Arguments:
#       locale          The locale to use.
#       src             The source string.
#       dest            (Optional) The translated string.  If omitted,
#                       the source string is used.
#
# Results:
#       Returns the new locale.

proc msgcat::mcset {locale src {dest ""}} {
    variable Msgs
    if {[llength [info level 0]] == 3} { ;# dest not specified
        set dest $src
    }

    set ns [uplevel 1 [list ::namespace current]]
    
    set locale [string tolower $locale]
    
    # create nested dictionaries if they do not exist
    if {![dict exists $Msgs $locale]} {
        dict set Msgs $locale  [dict create] 
    }
    if {![dict exists $Msgs $locale $ns]} {
        dict set Msgs $locale $ns [dict create]
    }
    dict set Msgs $locale $ns $src $dest
    return $dest
}

# msgcat::mcmset --
#
#       Set the translation for multiple strings in a specified locale.
#
# Arguments:
#       locale          The locale to use.
#       pairs           One or more src/dest pairs (must be even length)
#
# Results:
#       Returns the number of pairs processed

proc msgcat::mcmset {locale pairs } {
    variable Msgs

    set length [llength $pairs]
    if {$length % 2} {
        return -code error "bad translation list:\
                 should be \"[lindex [info level 0] 0] locale {src dest ...}\""
    }
    
    set locale [string tolower $locale]
    set ns [uplevel 1 [list ::namespace current]]

    # create nested dictionaries if they do not exist
    if {![dict exists $Msgs $locale]} {
        dict set Msgs $locale  [dict create] 
    }
    if {![dict exists $Msgs $locale $ns]} {
        dict set Msgs $locale $ns [dict create]
    }    
    foreach {src dest} $pairs {
        dict set Msgs $locale $ns $src $dest
    }

    return $length
}

# msgcat::mcunknown --
#
#       This routine is called by msgcat::mc if a translation cannot
#       be found for a string.  This routine is intended to be replaced
#       by an application specific routine for error reporting
#       purposes.  The default behavior is to return the source string.  
#       If additional args are specified, the format command will be used
#       to work them into the traslated string.
#
# Arguments:
#       locale          The current locale.
#       src             The string to be translated.
#       args            Args to pass to the format command
#
# Results:
#       Returns the translated value.

proc msgcat::mcunknown {locale src args} {
    if {[llength $args]} {
        return [format $src {*}$args]
    } else {
        return $src
    }
}

# msgcat::mcmax --
#
#       Calculates the maximum length of the translated strings of the given 
#       list.
#
# Arguments:
#       args    strings to translate.
#
# Results:
#       Returns the length of the longest translated string.

proc msgcat::mcmax {args} {
    set max 0
    foreach string $args {
        set translated [uplevel 1 [list [namespace origin mc] $string]]
        set len [string length $translated]
        if {$len>$max} {
            set max $len
        }
    }
    return $max
}

# Convert the locale values stored in environment variables to a form
# suitable for passing to [mclocale]
proc msgcat::ConvertLocale {value} {
    # Assume $value is of form: $language[_$territory][.$codeset][@modifier]
    # Convert to form: $language[_$territory][_$modifier]
    #
    # Comment out expanded RE version -- bugs alleged
    # regexp -expanded {
    #   ^               # Match all the way to the beginning
    #   ([^_.@]*)       # Match "lanugage"; ends with _, ., or @
    #   (_([^.@]*))?    # Match (optional) "territory"; starts with _
    #   ([.]([^@]*))?   # Match (optional) "codeset"; starts with .
    #   (@(.*))?        # Match (optional) "modifier"; starts with @
    #   $               # Match all the way to the end
    # } $value -> language _ territory _ codeset _ modifier
    if {![regexp {^([^_.@]+)(_([^.@]*))?([.]([^@]*))?(@(.*))?$} $value \
            -> language _ territory _ codeset _ modifier]} {
        return -code error "invalid locale '$value': empty language part"
    }
    set ret $language
    if {[string length $territory]} {
        append ret _$territory
    }
    if {[string length $modifier]} {
        append ret _$modifier
    }
    return $ret
}

# Initialize the default locale
proc msgcat::Init {} {
    #
    # set default locale, try to get from environment
    #
    foreach varName {LC_ALL LC_MESSAGES LANG} {
        if {[info exists ::env($varName)] && ("" ne $::env($varName))} {
            if {![catch {
                mclocale [ConvertLocale $::env($varName)]
            }]} {
                return
            }
        }
    }
    #
    # On Darwin, fallback to current CFLocale identifier if available.
    #
    if {$::tcl_platform(os) eq "Darwin" && $::tcl_platform(platform) eq "unix"
            && [info exists ::tcl::mac::locale] && $::tcl::mac::locale ne ""} {
        if {![catch {
            mclocale [ConvertLocale $::tcl::mac::locale]
        }]} {
            return
        }
    }
    #
    # The rest of this routine is special processing for Windows;
    # all other platforms, get out now.
    #
    if { $::tcl_platform(platform) ne "windows" } {
        mclocale C
        return
    }
    #
    # On Windows, try to set locale depending on registry settings,
    # or fall back on locale of "C".  
    #
    set key {HKEY_CURRENT_USER\Control Panel\International}
    if {[catch {package require registry}] \
            || [catch {registry get $key "locale"} locale]} {
        mclocale C
        return
    }
    #
    # Keep trying to match against smaller and smaller suffixes
    # of the registry value, since the latter hexadigits appear
    # to determine general language and earlier hexadigits determine
    # more precise information, such as territory.  For example,
    #     0409 - English - United States
    #     0809 - English - United Kingdom
    # Add more translations to the WinRegToISO639 array above.
    #
    variable WinRegToISO639
    set locale [string tolower $locale]
    while {[string length $locale]} {
        if {![catch {
                mclocale [ConvertLocale [dict get $WinRegToISO639 $locale]]
        }]} {
            return
        }
        set locale [string range $locale 1 end]
    }
    #
    # No translation known.  Fall back on "C" locale
    #
    mclocale C
}
msgcat::Init