#!/bin/sh
 # einfacher RSS Reader
 #  \
 exec wish $0 $@

 package require Tk
 package require opt

 source czrss.tcl

 namespace eval ::rssgui {
    #variable text
    variable counter

    proc init {} {
        variable counter
        set counter 0

        # white background weißer Hintergrund
        . configure -background white
        option add *background white

        # main windows | Hauptfenster
        text .text  -relief flat -wrap word \
            -selectbackground blue \
            -yscrollcommand {.sby set}  \
            -highlightthickness 0

        grid .text -row 1 -column 1 -sticky nesw

        scrollbar .sby -orient vert -command {.text yview} \
                        -highlightthickness 0
        grid .sby -row 1 -column 2 -sticky ns

        frame .buttons 
        grid .buttons -row 2 -columnspan 3 -sticky e 
        image create photo aus -file aus.gif
        button .buttons.exit -command {exit 0} \
            -image aus -relief flat \
            -highlightthickness 0
        pack .buttons.exit -anchor e

        grid rowconfigure . 0 -minsize 10
        grid rowconfigure . 1 -weight 1
        grid rowconfigure . 2 -minsize 10

        grid columnconfigure . 0 -minsize 10
        grid columnconfigure . 1 -weight 1
        grid columnconfigure . 2 -minsize 10
        grid columnconfigure . 3 -minsize 10
        
        # Configure text widget | Text konfigurieren
         .text tag configure title -foreground steelblue -font {Helvetica  12} \
            -spacing1 5 -spacing3 5
         .text tag configure description -foreground black \
             -spacing1 10 -lmargin1 20 -lmargin2 10 -spacing3 5 -elide true 
        .text tag configure gerade -background whitesmoke 
        .text tag configure ungerade -background white
        .text tag configure sichtbar -elide false
        .text conf -state disabled 
    }

    proc setFeed { url } {
        set doc [::czrss::doc create %AUTO% $url ]
        set channel [$doc channel]
        wm title . [$channel title]
        .text conf -state normal
        .text delete 0.0 end
        foreach item [ $doc items ] {
            insertMessage [$item title] [$item description] [$item link]
        }
        .text conf -state disabled        
    }

    # insert a message into the text widget
    proc insertMessage { title description url } {
        variable counter

        set id [ clock clicks]

        if {[expr [incr counter] % 2 ]} {
            set zeile gerade
        } else {
            set zeile ungerade
        }
        
        .text insert end "$title\n" [ list $zeile title $id]
        .text tag bind $id <Enter> [list ::rssgui::enterTag $id]
        .text tag bind $id <Double-1> [list ::rssgui::startBrowser $url]

        incr id
        .text insert end "$description\n" [ list $zeile description $id]
        .text tag bind $id <Double-1> [list ::rssgui::startBrowser $url]
    }

    # called when entering a taged item with the mouse in the text widget 
    proc enterTag { id } {
        set start [ lindex [.text tag nextrange $id 0.0 end] 0]
        set end   [ lindex [.text tag nextrange [expr $id +1 ] 0.0 end] 1]
        .text tag add sichtbar $start $end
        .text tag bind sichtbar <Leave> [list ::rssgui::leaveTag  $id]
    }

    # called when leaving a taged item with the mouse in the text widget 
    proc leaveTag { id } {
        .text tag remove sichtbar 0.0 end
    }
    # start a HTML browser on the local machine
    proc startBrowser {url} {
        puts "startBrowser $url"  
        
        # nimmt erstbesten browser
        foreach browser {galeon firefox mozilla konqueror netscape opera} {
            set binary [lindex [auto_execok $browser] 0]
            if {[string length $binary]} {
                catch {exec $binary $url &}
                break
            }
        }
    }
  }

  tcl::OptProc main {
    {url "RSS-Feed, z.B. http://www.tagesschau.de/newsticker.rdf" }
  } {

    rssgui::init
    rssgui::setFeed $url
  }

  if {[catch { eval main $argv } res]} {
    puts stderr $res
  } else {
    puts stdout $res
  }