#!/usr/bin/tclsh

if {[info commands lassign] == ""} {

# lassign --
#	Assigns list contents to given variables. This command
#	exists in Tcl 8.5, so the definition is conditional.
#
# Arguments:
#	list	A list of assigning values.
#	args	Variables to assign.
#
# Results:
#	The rest of a list.
#
# Side effects:
#	The given variables are assigned.

    proc lassign {list args} {
	foreach name $args {
	    upvar $name var

	    set var [lindex $list 0]
	    set list [lrange $list 1 end]
	}
	return $list
    }
}

# delsubstvar --
#	Removes substitution variable from a substvar file for a given
#	package in ./debian/ directory.
#
# Arguments:
#	package	    Name of a package (file $package.substvars is used).
#	substvar    Name of a substitution variable to delete.
#
# Results:
#	An empty string.
#
# Side effects:
#	File debian/$package.substvars is overwritten. The specified variable
#	is deleted.

proc delsubstvar {package substvar} {
    set substvarfile [file join debian $package.substvars]
    if {[file exists $substvarfile]} {
	set fd [open $substvarfile]
	set lines [split [string trim [read $fd]] "\n"]
	close $fd

	set fd [open $substvarfile w]
	foreach line $lines {
	    if {[string first $substvar= $line] != 0} {
		puts $fd $line
	    }
	}
	close $fd
    }
    return
}

# addsubstvar --
#	Adds a dependency to a substitution variable in a substvar file
#	for a given package in ./debian/ directory.
#
# Arguments:
#	package	    Name of a package (file $package.substvars is used).
#	substvar    Name of a substitution variable to add/change.
#	deppackage  An added substitution dependency string.
#
# Results:
#	An empty string.
#
# Side effects:
#	File debian/$package.substvars is overwritten. The specified depandency
#	string is added to the variable.

proc addsubstvar {package substvar deppackage} {
    set substvarfile [file join debian $package.substvars]
    if {[file exists $substvarfile]} {
	set fd [open $substvarfile]
	set lines [split [string trim [read $fd]] "\n"]
	close $fd

	set fd [open $substvarfile w]
	set found 0
	foreach line $lines {
	    if {[string first $substvar= $line] != 0} {
		puts $fd $line
	    } else {
		set items [split [string range $line [string length $substvar=] end] ","]
		set items1 {}
		foreach i $items {
		    lappend items1 [string trim $i]
		}
		lappend items1 $deppackage
		puts $fd $substvar=[join $items1 ", "]
		set found 1
	    }
	}
	if {!$found} {
	    puts $fd $substvar=$deppackage
	}
	close $fd
    } else {
	set fd [open $substvarfile w]
	puts $fd $substvar=$deppackage
	close $fd
    }
    return
}

# getpackages --
#	Parses debhelper command line options and debian/control file and
#	returns packages to act on.
#
# Arguments:
#	arglist	    Dephelper options (only -a, -i, -p, -N options are
#		    recognised).
#
# Results:
#	Package names to work on or error message and exit if debian/control
#	is unreadable or unknown option is specified.
#
# Side effects:
#	None.

proc getpackages {arglist} {
    if {[catch {open [file join debian control]} fd]} {
	puts [format "cannot read debian/control: %s" $fd]
	exit 1
    } else {
	set arches all
	set excluded {}
	set explicit {}
	while {[llength $arglist] > 0} {
	    set arglist [lassign $arglist opt]
	    switch -glob -- $opt {
		-a -
		--arch {
		    # Only the last -a or -i options takes effect
		    set arches arch
		}
		-i -
		--indep {
		    # Only the last -a or -i options takes effect
		    set arches indep
		}
		-s -
		--same-arch {
		    puts "options -s and --same-arch aren't supported yet"
		    exit 1
		}
		-p* {
		    lappend explicit [string range $opt 2 end]
		}
		--package=* {
		    lappend explicit [string range $opt 10 end]
		}
		-N* {
		    lappend excluded [string range $opt 2 end]
		}
		--no-package=* {
		    lappend excluded [string range $opt 13 end]
		}
		default {
		    puts [format "unknown option %s" $opt]
		    exit 1
		}
	    }
	}

	set data [read $fd]
	regsub -all {\n( |\t)} $data {\1} data ; # Join up all continuatioin lines
	set lines [split $data "\n"]
	lappend lines "" ; # If debian/config doesn't have a trailing LF
	close $fd
	set packages {}
	set allpackages {}

	set package ""
	set arch ""
	set vars {}
	foreach line $lines {
	    switch -glob -- $line {
		"Package: *" {
		    set package [string trim [string range $line 9 end]]
		}
		"Architecture: *" {
		    set arch [string trim [string range $line 14 end]]
		}
		"Pre-Depends: *" -
		"Depends: *" -
		"Recommends: *" -
		"Suggests: *" -
		"Enhances: *" -
		"Breaks: *" -
		"Conflicts: *" -
		"Provides: *" -
		"Replaces: *" {
		    set vars [concat $vars [regexp -all -inline {\$\{\S*\}} $line]]
		}
		"" {
		    if {$package == ""} {
			# Two LF in a row or the end of a source package
		    } elseif {[lsearch -exact $excluded $package] >= 0} {
			# The package is excluded by -Npackage
		    } elseif {[lsearch -exact $explicit $package] >= 0} {
			# The package is explicitly required
			lappend packages $package $vars
		    } elseif {$arches == "arch" && $arch != "all"} {
			# Arch dependent packages are requested
			lappend packages $package $vars
		    } elseif {$arches == "indep" && $arch == "all"} {
			# Arch independent packages are requested
			lappend packages $package $vars
		    } elseif {$arches == "all"} {
			lappend allpackages $package $vars
		    }
		    set package ""
		    set arch ""
		    set vars {}
		}
	    }
	}
	if {$arches == "all" && [llength $packages] == 0} {
	    # There aren't explicitly requested packages
	    set packages $allpackages
	}
	return $packages
    }
}

set ver "8.6"

set tclver "8.6.9+dfsg-2"
if {$tclver == ""} {
    set tcldep ""
} else {
    set tcldep " (>= $tclver)"
}

set tkver "8.6.9-2"
if {$tkver == ""} {
    set tkdep ""
} else {
    set tkdep " (>= $tkver)"
}

set version "8.6.0-2"
if {$version == ""} {
    set dep ""
} else {
    set dep " (>= $version)"
}

foreach {package vars} [getpackages $argv] {
    delsubstvar $package "libtclXY:Depends"
    if {[lsearch -exact $vars "\${libtclXY:Depends}"] >= 0} {
	addsubstvar $package "libtclXY:Depends" "libtcl$ver$tcldep"
    }
    delsubstvar $package "libtcl:Depends"
    if {[lsearch -exact $vars "\${libtcl:Depends}"] >= 0} {
	addsubstvar $package "libtcl:Depends" "libtcl$ver$tcldep | libtcl"
    }
    delsubstvar $package "tclXY:Depends"
    if {[lsearch -exact $vars "\${tclXY:Depends}"] >= 0} {
	addsubstvar $package "tclXY:Depends" "tcl$ver$tcldep"
    }
    delsubstvar $package "tcl:Depends"
    if {[lsearch -exact $vars "\${tcl:Depends}"] >= 0} {
	addsubstvar $package "tcl:Depends" "tcl$dep"
    }
    # tclsh:Depends is retained for backward compatibility
    delsubstvar $package "tclsh:Depends"
    if {[lsearch -exact $vars "\${tclsh:Depends}"] >= 0} {
	addsubstvar $package "tclsh:Depends" "tcl$dep"
    }
    delsubstvar $package "libtkXY:Depends"
    if {[lsearch -exact $vars "\${libtkXY:Depends}"] >= 0} {
	addsubstvar $package "libtkXY:Depends" "libtk$ver$tkdep"
    }
    delsubstvar $package "libtk:Depends"
    if {[lsearch -exact $vars "\${libtk:Depends}"] >= 0} {
	addsubstvar $package "libtk:Depends" "libtk$ver$tkdep | libtk"
    }
    delsubstvar $package "tkXY:Depends"
    if {[lsearch -exact $vars "\${tkXY:Depends}"] >= 0} {
	addsubstvar $package "tkXY:Depends" "tk$ver$tkdep"
    }
    delsubstvar $package "tk:Depends"
    if {[lsearch -exact $vars "\${tk:Depends}"] >= 0} {
	addsubstvar $package "tk:Depends" "tk$dep"
    }
    # wish:Depends is retained for backward compatibility
    delsubstvar $package "wish:Depends"
    if {[lsearch -exact $vars "\${wish:Depends}"] >= 0} {
	addsubstvar $package "wish:Depends" "tk$dep"
    }
}