# git-gui misc. commit reading/writing support
# Copyright (C) 2006, 2007 Shawn Pearce

proc load_last_commit {} {
        global HEAD PARENT MERGE_HEAD commit_type ui_comm
        global repo_config

        if {[llength $PARENT] == 0} {
                error_popup [mc "There is nothing to amend.

You are about to create the initial commit.  There is no commit before this to amend.
"]
                return
        }

        repository_state curType curHEAD curMERGE_HEAD
        if {$curType eq {merge}} {
                error_popup [mc "Cannot amend while merging.

You are currently in the middle of a merge that has not been fully completed.  You cannot amend the prior commit unless you first abort the current merge activity.
"]
                return
        }

        set msg {}
        set parents [list]
        if {[catch {
                        set fd [git_read cat-file commit $curHEAD]
                        fconfigure $fd -encoding binary -translation lf
                        # By default commits are assumed to be in utf-8
                        set enc utf-8
                        while {[gets $fd line] > 0} {
                                if {[string match {parent *} $line]} {
                                        lappend parents [string range $line 7 end]
                                } elseif {[string match {encoding *} $line]} {
                                        set enc [string tolower [string range $line 9 end]]
                                }
                        }
                        set msg [read $fd]
                        close $fd

                        set enc [tcl_encoding $enc]
                        if {$enc ne {}} {
                                set msg [encoding convertfrom $enc $msg]
                        }
                        set msg [string trim $msg]
                } err]} {
                error_popup [strcat [mc "Error loading commit data for amend:"] "\n\n$err"]
                return
        }

        set HEAD $curHEAD
        set PARENT $parents
        set MERGE_HEAD [list]
        switch -- [llength $parents] {
        0       {set commit_type amend-initial}
        1       {set commit_type amend}
        default {set commit_type amend-merge}
        }

        $ui_comm delete 0.0 end
        $ui_comm insert end $msg
        $ui_comm edit reset
        $ui_comm edit modified false
        rescan ui_ready
}

set GIT_COMMITTER_IDENT {}

proc committer_ident {} {
        global GIT_COMMITTER_IDENT

        if {$GIT_COMMITTER_IDENT eq {}} {
                if {[catch {set me [git var GIT_COMMITTER_IDENT]} err]} {
                        error_popup [strcat [mc "Unable to obtain your identity:"] "\n\n$err"]
                        return {}
                }
                if {![regexp {^(.*) [0-9]+ [-+0-9]+$} \
                        $me me GIT_COMMITTER_IDENT]} {
                        error_popup [strcat [mc "Invalid GIT_COMMITTER_IDENT:"] "\n\n$me"]
                        return {}
                }
        }

        return $GIT_COMMITTER_IDENT
}

proc do_signoff {} {
        global ui_comm

        set me [committer_ident]
        if {$me eq {}} return

        set sob "Signed-off-by: $me"
        set last [$ui_comm get {end -1c linestart} {end -1c}]
        if {$last ne $sob} {
                $ui_comm edit separator
                if {$last ne {}
                        && ![regexp {^[A-Z][A-Za-z]*-[A-Za-z-]+: *} $last]} {
                        $ui_comm insert end "\n"
                }
                $ui_comm insert end "\n$sob"
                $ui_comm edit separator
                $ui_comm see end
        }
}

proc create_new_commit {} {
        global commit_type ui_comm

        set commit_type normal
        $ui_comm delete 0.0 end
        $ui_comm edit reset
        $ui_comm edit modified false
        rescan ui_ready
}

proc commit_tree {} {
        global HEAD commit_type file_states ui_comm repo_config
        global pch_error

        if {[committer_ident] eq {}} return
        if {![lock_index update]} return

        # -- Our in memory state should match the repository.
        #
        repository_state curType curHEAD curMERGE_HEAD
        if {[string match amend* $commit_type]
                && $curType eq {normal}
                && $curHEAD eq $HEAD} {
        } elseif {$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 another commit can be created.

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

        # -- At least one file should differ in the index.
        #
        set files_ready 0
        foreach path [array names file_states] {
                switch -glob -- [lindex $file_states($path) 0] {
                _? {continue}
                A? -
                D? -
                T_ -
                M? {set files_ready 1}
                _U -
                U? {
                        error_popup [mc "Unmerged files cannot be committed.

File %s has merge conflicts.  You must resolve them and stage the file before committing.
" [short_path $path]]
                        unlock_index
                        return
                }
                default {
                        error_popup [mc "Unknown file state %s detected.

File %s cannot be committed by this program.
" [lindex $s 0] [short_path $path]]
                }
                }
        }
        if {!$files_ready && ![string match *merge $curType] && ![is_enabled nocommit]} {
                info_popup [mc "No changes to commit.

You must stage at least 1 file before you can commit.
"]
                unlock_index
                return
        }

        if {[is_enabled nocommitmsg]} { do_quit 0 }

        # -- A message is required.
        #
        set msg [string trim [$ui_comm get 1.0 end]]
        regsub -all -line {[ \t\r]+$} $msg {} msg
        if {$msg eq {}} {
                error_popup [mc "Please supply a commit message.

A good commit message has the following format:

- First line: Describe in one sentence what you did.
- Second line: Blank
- Remaining lines: Describe why this change is good.
"]
                unlock_index
                return
        }

        # -- Build the message file.
        #
        set msg_p [gitdir GITGUI_EDITMSG]
        set msg_wt [open $msg_p w]
        fconfigure $msg_wt -translation lf
        if {[catch {set enc $repo_config(i18n.commitencoding)}]} {
                set enc utf-8
        }
        set use_enc [tcl_encoding $enc]
        if {$use_enc ne {}} {
                fconfigure $msg_wt -encoding $use_enc
        } else {
                error_popup [mc "warning: Tcl does not support encoding '%s'." $enc]
                fconfigure $msg_wt -encoding utf-8
        }
        puts $msg_wt $msg
        close $msg_wt

        if {[is_enabled nocommit]} { do_quit 0 }

        # -- Run the pre-commit hook.
        #
        set fd_ph [githook_read pre-commit]
        if {$fd_ph eq {}} {
                commit_commitmsg $curHEAD $msg_p
                return
        }

        ui_status [mc "Calling pre-commit hook..."]
        set pch_error {}
        fconfigure $fd_ph -blocking 0 -translation binary -eofchar {}
        fileevent $fd_ph readable \
                [list commit_prehook_wait $fd_ph $curHEAD $msg_p]
}

proc commit_prehook_wait {fd_ph curHEAD msg_p} {
        global pch_error

        append pch_error [read $fd_ph]
        fconfigure $fd_ph -blocking 1
        if {[eof $fd_ph]} {
                if {[catch {close $fd_ph}]} {
                        catch {file delete $msg_p}
                        ui_status [mc "Commit declined by pre-commit hook."]
                        hook_failed_popup pre-commit $pch_error
                        unlock_index
                } else {
                        commit_commitmsg $curHEAD $msg_p
                }
                set pch_error {}
                return
        }
        fconfigure $fd_ph -blocking 0
}

proc commit_commitmsg {curHEAD msg_p} {
        global pch_error

        # -- Run the commit-msg hook.
        #
        set fd_ph [githook_read commit-msg $msg_p]
        if {$fd_ph eq {}} {
                commit_writetree $curHEAD $msg_p
                return
        }

        ui_status [mc "Calling commit-msg hook..."]
        set pch_error {}
        fconfigure $fd_ph -blocking 0 -translation binary -eofchar {}
        fileevent $fd_ph readable \
                [list commit_commitmsg_wait $fd_ph $curHEAD $msg_p]
}

proc commit_commitmsg_wait {fd_ph curHEAD msg_p} {
        global pch_error

        append pch_error [read $fd_ph]
        fconfigure $fd_ph -blocking 1
        if {[eof $fd_ph]} {
                if {[catch {close $fd_ph}]} {
                        catch {file delete $msg_p}
                        ui_status [mc "Commit declined by commit-msg hook."]
                        hook_failed_popup commit-msg $pch_error
                        unlock_index
                } else {
                        commit_writetree $curHEAD $msg_p
                }
                set pch_error {}
                return
        }
        fconfigure $fd_ph -blocking 0
}

proc commit_writetree {curHEAD msg_p} {
        ui_status [mc "Committing changes..."]
        set fd_wt [git_read write-tree]
        fileevent $fd_wt readable \
                [list commit_committree $fd_wt $curHEAD $msg_p]
}

proc commit_committree {fd_wt curHEAD msg_p} {
        global HEAD PARENT MERGE_HEAD commit_type
        global current_branch
        global ui_comm selected_commit_type
        global file_states selected_paths rescan_active
        global repo_config

        gets $fd_wt tree_id
        if {[catch {close $fd_wt} err]} {
                catch {file delete $msg_p}
                error_popup [strcat [mc "write-tree failed:"] "\n\n$err"]
                ui_status [mc "Commit failed."]
                unlock_index
                return
        }

        # -- Verify this wasn't an empty change.
        #
        if {$commit_type eq {normal}} {
                set fd_ot [git_read cat-file commit $PARENT]
                fconfigure $fd_ot -encoding binary -translation lf
                set old_tree [gets $fd_ot]
                close $fd_ot

                if {[string equal -length 5 {tree } $old_tree]
                        && [string length $old_tree] == 45} {
                        set old_tree [string range $old_tree 5 end]
                } else {
                        error [mc "Commit %s appears to be corrupt" $PARENT]
                }

                if {$tree_id eq $old_tree} {
                        catch {file delete $msg_p}
                        info_popup [mc "No changes to commit.

No files were modified by this commit and it was not a merge commit.

A rescan will be automatically started now.
"]
                        unlock_index
                        rescan {ui_status [mc "No changes to commit."]}
                        return
                }
        }

        # -- Create the commit.
        #
        set cmd [list commit-tree $tree_id]
        foreach p [concat $PARENT $MERGE_HEAD] {
                lappend cmd -p $p
        }
        lappend cmd <$msg_p
        if {[catch {set cmt_id [eval git $cmd]} err]} {
                catch {file delete $msg_p}
                error_popup [strcat [mc "commit-tree failed:"] "\n\n$err"]
                ui_status [mc "Commit failed."]
                unlock_index
                return
        }

        # -- Update the HEAD ref.
        #
        set reflogm commit
        if {$commit_type ne {normal}} {
                append reflogm " ($commit_type)"
        }
        set msg_fd [open $msg_p r]
        gets $msg_fd subject
        close $msg_fd
        append reflogm {: } $subject
        if {[catch {
                        git update-ref -m $reflogm HEAD $cmt_id $curHEAD
                } err]} {
                catch {file delete $msg_p}
                error_popup [strcat [mc "update-ref failed:"] "\n\n$err"]
                ui_status [mc "Commit failed."]
                unlock_index
                return
        }

        # -- Cleanup after ourselves.
        #
        catch {file delete $msg_p}
        catch {file delete [gitdir MERGE_HEAD]}
        catch {file delete [gitdir MERGE_MSG]}
        catch {file delete [gitdir SQUASH_MSG]}
        catch {file delete [gitdir GITGUI_MSG]}

        # -- Let rerere do its thing.
        #
        if {[get_config rerere.enabled] eq {}} {
                set rerere [file isdirectory [gitdir rr-cache]]
        } else {
                set rerere [is_config_true rerere.enabled]
        }
        if {$rerere} {
                catch {git rerere}
        }

        # -- Run the post-commit hook.
        #
        set fd_ph [githook_read post-commit]
        if {$fd_ph ne {}} {
                upvar #0 pch_error$cmt_id pc_err
                set pc_err {}
                fconfigure $fd_ph -blocking 0 -translation binary -eofchar {}
                fileevent $fd_ph readable \
                        [list commit_postcommit_wait $fd_ph $cmt_id]
        }

        $ui_comm delete 0.0 end
        $ui_comm edit reset
        $ui_comm edit modified false
        if {$::GITGUI_BCK_exists} {
                catch {file delete [gitdir GITGUI_BCK]}
                set ::GITGUI_BCK_exists 0
        }

        if {[is_enabled singlecommit]} { do_quit 0 }

        # -- Update in memory status
        #
        set selected_commit_type new
        set commit_type normal
        set HEAD $cmt_id
        set PARENT $cmt_id
        set MERGE_HEAD [list]

        foreach path [array names file_states] {
                set s $file_states($path)
                set m [lindex $s 0]
                switch -glob -- $m {
                _O -
                _M -
                _D {continue}
                __ -
                A_ -
                M_ -
                T_ -
                D_ {
                        unset file_states($path)
                        catch {unset selected_paths($path)}
                }
                DO {
                        set file_states($path) [list _O [lindex $s 1] {} {}]
                }
                AM -
                AD -
                MM -
                MD {
                        set file_states($path) [list \
                                _[string index $m 1] \
                                [lindex $s 1] \
                                [lindex $s 3] \
                                {}]
                }
                }
        }

        display_all_files
        unlock_index
        reshow_diff
        ui_status [mc "Created commit %s: %s" [string range $cmt_id 0 7] $subject]
}

proc commit_postcommit_wait {fd_ph cmt_id} {
        upvar #0 pch_error$cmt_id pch_error

        append pch_error [read $fd_ph]
        fconfigure $fd_ph -blocking 1
        if {[eof $fd_ph]} {
                if {[catch {close $fd_ph}]} {
                        hook_failed_popup post-commit $pch_error 0
                }
                unset pch_error
                return
        }
        fconfigure $fd_ph -blocking 0
}