# git-gui branch merge support
# Copyright (C) 2006, 2007 Shawn Pearce

class merge {

field w         ; # top level window
field w_list    ; # widget of available branches
field list      ; # list of available branches

method _can_merge {} {
        global HEAD commit_type file_states

        if {[string match amend* $commit_type]} {
                info_popup {Cannot merge while amending.

You must finish amending this commit before starting any type of merge.
}
                return 0
        }

        if {[committer_ident] eq {}} {return 0}
        if {![lock_index merge]} {return 0}

        # -- Our in memory state should match the repository.
        #
        repository_state curType curHEAD curMERGE_HEAD
        if {$commit_type ne $curType || $HEAD ne $curHEAD} {
                info_popup {Last scanned state does not match repository state.

Another Git program has modified this repository since the last scan.  A rescan must be performed before a merge can be performed.

The rescan will be automatically started now.
}
                unlock_index
                rescan ui_ready
                return 0
        }

        foreach path [array names file_states] {
                switch -glob -- [lindex $file_states($path) 0] {
                _O {
                        continue; # and pray it works!
                }
                U? {
                        error_popup "You are in the middle of a conflicted merge.

File [short_path $path] has merge conflicts.

You must resolve them, add the file, and commit to complete the current merge.  Only then can you begin another merge.
"
                        unlock_index
                        return 0
                }
                ?? {
                        error_popup "You are in the middle of a change.

File [short_path $path] is modified.

You should complete the current commit before starting a merge.  Doing so will help you abort a failed merge, should the need arise.
"
                        unlock_index
                        return 0
                }
                }
        }

        return 1
}

method _rev {} {
        set i [$w_list curselection]
        if {$i >= 0} {
                return [lindex [lindex $list $i] 0]
        }
        return {}
}

method _visualize {} {
        set rev [_rev $this]
        if {$rev ne {}} {
                do_gitk [list $rev --not HEAD]
        }
}

method _start {} {
        global HEAD current_branch

        set name [_rev $this]
        if {$name eq {}} {
                return
        }

        set cmd [list git merge $name]
        set msg "Merging $current_branch and $name"
        ui_status "$msg..."
        set cons [console::new "Merge" $cmd]
        console::exec $cons $cmd [cb _finish $cons]

        wm protocol $w WM_DELETE_WINDOW {}
        destroy $w
}

method _finish {cons ok} {
        console::done $cons $ok
        if {$ok} {
                set msg {Merge completed successfully.}
        } else {
                set msg {Merge failed.  Conflict resolution is required.}
        }
        unlock_index
        rescan [list ui_status $msg]
        delete_this
}

constructor dialog {} {
        global current_branch
        global M1B

        if {![_can_merge $this]} {
                delete_this
                return
        }

        set fmt {list %(objectname) %(*objectname) %(refname) %(subject)}
        set fr_fd [git_read for-each-ref \
                --tcl \
                --format=$fmt \
                refs/heads \
                refs/remotes \
                refs/tags \
                ]
        fconfigure $fr_fd -translation binary
        while {[gets $fr_fd line] > 0} {
                set line [eval $line]
                set ref [lindex $line 2]
                regsub ^refs/(heads|remotes|tags)/ $ref {} ref
                set subj($ref) [lindex $line 3]
                lappend sha1([lindex $line 0]) $ref
                if {[lindex $line 1] ne {}} {
                        lappend sha1([lindex $line 1]) $ref
                }
        }
        close $fr_fd

        set list [list]
        set fr_fd [git_read rev-list --all --not HEAD]
        while {[gets $fr_fd line] > 0} {
                if {[catch {set ref $sha1($line)}]} continue
                foreach n $ref {
                        lappend list [list $n $line]
                }
        }
        close $fr_fd
        set list [lsort -unique $list]

        make_toplevel top w
        wm title $top "[appname] ([reponame]): Merge"
        if {$top ne {.}} {
                wm geometry $top "+[winfo rootx .]+[winfo rooty .]"
        }

        set _visualize [cb _visualize]
        set _start [cb _start]

        label $w.header \
                -text "Merge Into $current_branch" \
                -font font_uibold
        pack $w.header -side top -fill x

        frame $w.buttons
        button $w.buttons.visualize -text Visualize -command $_visualize
        pack $w.buttons.visualize -side left
        button $w.buttons.create -text Merge -command $_start
        pack $w.buttons.create -side right
        button $w.buttons.cancel \
                -text {Cancel} \
                -command [cb _cancel]
        pack $w.buttons.cancel -side right -padx 5
        pack $w.buttons -side bottom -fill x -pady 10 -padx 10

        labelframe $w.source -text {Source Branches}
        set w_list $w.source.l
        listbox $w_list \
                -height 10 \
                -width 70 \
                -font font_diff \
                -selectmode browse \
                -yscrollcommand [list $w.source.sby set]
        scrollbar $w.source.sby -command [list $w_list yview]
        pack $w.source.sby -side right -fill y
        pack $w_list -side left -fill both -expand 1
        pack $w.source -fill both -expand 1 -pady 5 -padx 5

        foreach ref $list {
                set n [lindex $ref 0]
                if {[string length $n] > 20} {
                        set n "[string range $n 0 16]..."
                }
                $w_list insert end [format {%s %-20s %s} \
                        [string range [lindex $ref 1] 0 5] \
                        $n \
                        $subj([lindex $ref 0])]
        }

        bind $w_list <Key-K> [list event generate %W <Shift-Key-Up>]
        bind $w_list <Key-J> [list event generate %W <Shift-Key-Down>]
        bind $w_list <Key-k> [list event generate %W <Key-Up>]
        bind $w_list <Key-j> [list event generate %W <Key-Down>]
        bind $w_list <Key-h> [list event generate %W <Key-Left>]
        bind $w_list <Key-l> [list event generate %W <Key-Right>]
        bind $w_list <Key-v> $_visualize

        bind $w <$M1B-Key-Return> $_start
        bind $w <Visibility> [cb _visible]
        bind $w <Key-Escape> [cb _cancel]
        wm protocol $w WM_DELETE_WINDOW [cb _cancel]
        tkwait window $w
}

method _visible {} {
        grab $w
        focus $w_list
}

method _cancel {} {
        wm protocol $w WM_DELETE_WINDOW {}
        unlock_index
        destroy $w
        delete_this
}

}

namespace eval merge {

proc reset_hard {} {
        global HEAD commit_type file_states

        if {[string match amend* $commit_type]} {
                info_popup {Cannot abort while amending.

You must finish amending this commit.
}
                return
        }

        if {![lock_index abort]} return

        if {[string match *merge* $commit_type]} {
                set op merge
        } else {
                set op commit
        }

        if {[ask_popup "Abort $op?

Aborting the current $op will cause *ALL* uncommitted changes to be lost.

Continue with aborting the current $op?"] eq {yes}} {
                set fd [git_read read-tree --reset -u HEAD]
                fconfigure $fd -blocking 0 -translation binary
                fileevent $fd readable [namespace code [list _reset_wait $fd]]
                ui_status {Aborting... please wait...}
        } else {
                unlock_index
        }
}

proc _reset_wait {fd} {
        global ui_comm

        read $fd
        if {[eof $fd]} {
                close $fd
                unlock_index

                $ui_comm delete 0.0 end
                $ui_comm edit modified false

                catch {file delete [gitdir MERGE_HEAD]}
                catch {file delete [gitdir rr-cache MERGE_RR]}
                catch {file delete [gitdir SQUASH_MSG]}
                catch {file delete [gitdir MERGE_MSG]}
                catch {file delete [gitdir GITGUI_MSG]}

                rescan {ui_status {Abort completed.  Ready.}}
        }
}

}