# $Id$
# Provides for deducing the location of Tkabber config directory depending
# on the current platform.

namespace eval config {}

# Deduces the location of the "Application Data" directory
# (in its wide sense) on the current Windows platform.
# See: http://ru.tkabber.jabe.ru/index.php/Config_dir
proc config::appdata_windows {} {
    global env

    if {[info exists env(APPDATA)]} {
	return $env(APPDATA)
    }

    if {![catch {package require registry}]} {
	set key {HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders}
	if {![catch {registry get $key AppData} dir]} {
	    return $dir
	}
    }

    return {}
}

# Copies the contents of dir $from under dir $to using bells'n'whistles.
# NOTE that at the time of invocation:
# * $from MUST exist
# * $to MUST NOT exist.
# Returns true if copying succeeded, false otherwise.
proc config::transfer_dir {from to} {
    wm withdraw .
    wm title . [::msgcat::mc "Attention"]
    pack [message .msg -aspect 50000 \
	-text [::msgcat::mc "Please, be patient while Tkabber\
	    configuration directory is being transferred\
	    to the new location"]] -fill both -expand yes
    #::tk::PlaceWindow .
    wm deiconify .

    set failed [catch {file copy $from $to} err]

    if {$failed} {
	tk_messageBox -icon error \
	    -title [::msgcat::mc "Attention"] \
	    -message [::msgcat::mc "Tkabber configuration directory\
		transfer failed with:\n%s\n\
		Tkabber will use the old directory:\n%s" $err $from]
    } else {
	set to [file nativename $to]
	tk_messageBox \
	    -title [::msgcat::mc "Attention"] \
	    -message [format \
		[::msgcat::mc "Your new Tkabber config\
		    directory is now:\n%s\nYou can delete the old one:\n%s"] \
		    $to $from]
    }

    destroy .msg

    expr {!$failed}
}

# Based on the current platform, chooses the location of the Tkabber's
# config dir and sets the "configdir" global variable to its pathname.
# "TKABBER_HOME" env var overrides any guessing.
# NOTE that this proc now tries to copy contents of the "old-style"
# ~/.tkabber config dir to the new location, if needed, to provide
# smooth upgrade for Tkabber users on Windows.
# This behaviour should be lifted eventually in the future.

if {![info exists env(TKABBER_HOME)]} {
    switch -- $tcl_platform(platform) {
	unix {
	    set configdir ~/.tkabber
	}
	windows {
	    set dir [config::appdata_windows]
	    if {$dir != {}} {
		set configdir [file join $dir Tkabber]
	    } else {
	    # Fallback default (depends on Tcl's idea about ~):
	    set configdir [file join ~ .tkabber]
	    }
	}
	macintosh {
	    set configdir [file join ~ Library "Application Support" Tkabber]
	}
    }

    set env(TKABBER_HOME) $configdir
} else {
    set configdir $env(TKABBER_HOME)
}

if {$tcl_version >= 8.4} {
    set configdir [file normalize $configdir]
}

# This should be lifted in the next release after introduction
# of configdir.
# TODO: what perms does the dest dir of [file copy] receive?
# Since it's only needed for Windows, we don't really care now.
if {![file exists $configdir] && [file isdir ~/.tkabber]} {
    if {![config::transfer_dir ~/.tkabber $configdir]} {
	# Transfer error-case fallback:
	set configdir ~/.tkabber
    }
}

file mkdir $configdir

# vim:ts=8:sw=4:sts=4:noet