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

class merge {

field w         ; # top level window
field w_rev     ; # mega-widget to pick the revision to merge

method _can_merge {} {
        global HEAD commit_type file_states

        if {[string match amend* $commit_type]} {
                info_popup [mc "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 [mc "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 -
                U? {
                        error_popup [mc "You are in the middle of a conflicted merge.

File %s has merge conflicts.

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

File %s 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.
" [short_path $path]]
                        unlock_index
                        return 0
                }
                }
        }

        return 1
}

method _rev {} {
        if {[catch {$w_rev commit_or_die}]} {
                return {}
        }
        return [$w_rev get]
}

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

method _start {} {
        global HEAD current_branch remote_url
        global _last_merged_branch

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

        set spec [$w_rev get_tracking_branch]
        set cmit [$w_rev get_commit]

        set fh [open [gitdir FETCH_HEAD] w]
        fconfigure $fh -translation lf
        if {$spec eq {}} {
                set remote .
                set branch $name
                set stitle $branch
        } else {
                set remote $remote_url([lindex $spec 1])
                if {[regexp {^[^:@]*@[^:]*:/} $remote]} {
                        regsub {^[^:@]*@} $remote {} remote
                }
                set branch [lindex $spec 2]
                set stitle [mc "%s of %s" $branch $remote]
        }
        regsub ^refs/heads/ $branch {} branch
        puts $fh "$cmit\t\tbranch '$branch' of $remote"
        close $fh
        set _last_merged_branch $branch

        set cmd [list git merge --strategy=recursive FETCH_HEAD]

        ui_status [mc "Merging %s and %s..." $current_branch $stitle]
        set cons [console::new [mc "Merge"] "merge $stitle"]
        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 [mc "Merge completed successfully."]
        } else {
                set msg [mc "Merge failed.  Conflict resolution is required."]
        }
        unlock_index
        rescan [list ui_status $msg]
        delete_this
}

constructor dialog {} {
        global current_branch
        global M1B use_ttk NS

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

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

        set _start [cb _start]

        ${NS}::label $w.header \
                -text [mc "Merge Into %s" $current_branch] \
                -font font_uibold
        pack $w.header -side top -fill x

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

        set w_rev [::choose_rev::new_unmerged $w.rev [mc "Revision To Merge"]]
        pack $w.rev -anchor nw -fill both -expand 1 -pady 5 -padx 5

        bind $w <$M1B-Key-Return> $_start
        bind $w <Key-Return> $_start
        bind $w <Key-Escape> [cb _cancel]
        wm protocol $w WM_DELETE_WINDOW [cb _cancel]

        bind $w.buttons.merge <Visibility> [cb _visible]
        tkwait window $w
}

method _visible {} {
        grab $w
        if {[is_config_true gui.matchtrackingbranch]} {
                $w_rev pick_tracking_branch
        }
        $w_rev focus_filter
}

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 [mc "Cannot abort while amending.

You must finish amending this commit.
"]
                return
        }

        if {![lock_index abort]} return

        if {[string match *merge* $commit_type]} {
                set op_question [mc "Abort merge?

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

Continue with aborting the current merge?"]
        } else {
                set op_question [mc "Reset changes?

Resetting the changes will cause *ALL* uncommitted changes to be lost.

Continue with resetting the current changes?"]
        }

        if {[ask_popup $op_question] eq {yes}} {
                set fd [git_read --stderr read-tree --reset -u -v HEAD]
                fconfigure $fd -blocking 0 -translation binary
                fileevent $fd readable [namespace code [list _reset_wait $fd]]
                $::main_status start [mc "Aborting"] [mc "files reset"]
        } else {
                unlock_index
        }
}

proc _reset_wait {fd} {
        global ui_comm

        $::main_status update_meter [read $fd]

        fconfigure $fd -blocking 1
        if {[eof $fd]} {
                set fail [catch {close $fd} err]
                $::main_status stop
                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 MERGE_RR]}
                catch {file delete [gitdir SQUASH_MSG]}
                catch {file delete [gitdir MERGE_MSG]}
                catch {file delete [gitdir GITGUI_MSG]}

                if {$fail} {
                        warn_popup "[mc "Abort failed."]\n\n$err"
                }
                rescan {ui_status [mc "Abort completed.  Ready."]}
        } else {
                fconfigure $fd -blocking 0
        }
}

}