Make session -p work remotely, also make host a flag

session/_session

@@ -34,7 +34,7 @@ __session_hosts() {
 }
 
 _arguments \
-  '(- *)'{-h,--help}'[Show usage information]' \
-  '(- *)'{-p,--project}'[Create or attach to a session for a project in ~/Projects]:project:__session_projects' \
-  ':session:__session_sessions' \
-  ':host:__session_hosts'
+  '(- : *)'{-h,--help}'[Show usage information]' \
+  '(-H --host)'{-H,--host}'[Create or attach to the session on a remote host via ssh]:host:__session_hosts' \
+  '(-p --project :)'{-p,--project}'[Create or attach to a session for a project in ~/Projects]:project:__session_projects' \
+  '(-p --project)1:session:__session_sessions'

session/session.plugin.zsh

@@ -1,28 +1,97 @@
 session() {
-  if [[ "$1" == "" ]]; then
-    echo "usage: session [-h] <name> [<host>]
-       session -p <project>"
-  elif [[ "$1" == "-h" ]] || [[ "$1" == "--help" ]]; then
-    echo "usage: session [-h] <name> [<host>]
-       session -p <project>
+  local usage="usage: session [-h] [-H <host>] <name>
+       session [-H <host>] -p <project>"
+  local name="" project="" host=""
 
-Create or attach to a tmux session by name either locally on on a remote host
+  while [[ $# -gt 0 ]]; do
+    case "$1" in
+      -h|--help)
+        echo "$usage
+
+Create or attach to a tmux session by name either locally or on a remote host
 via ssh.
 
 With -p create or attach to a session for <project>, a path in ~/Projects with
 the prefix removed, which must be a git repository. The session is named after
 the project and holds a home window plus a window at the project, named after
 its default branch.
+
+With -H create or attach to the session on <host> via ssh, where <host> is
+either a hostname or a shortname defined in ~/.config/session. Combined with -p
+the project is resolved on <host>, not locally. Not allowed inside a tmux
+session.
 "
-  elif [[ "$1" == "-p" ]] || [[ "$1" == "--project" ]]; then
-    local project=${2%/}
-    if [[ "$project" == "" ]]; then
-      echo "$fg[red]error:$reset_color missing <project> argument"
+        return 0
+        ;;
+      -p|--project)
+        if [[ "$2" == "" ]]; then
+          echo "$fg[red]error:$reset_color missing <project> argument"
+          return 1
+        fi
+        project=${2%/}
+        shift 2
+        ;;
+      -H|--host)
+        if [[ "$2" == "" ]]; then
+          echo "$fg[red]error:$reset_color missing <host> argument"
+          return 1
+        fi
+        host=$2
+        shift 2
+        ;;
+      -*)
+        echo "$fg[red]error:$reset_color unknown option: $1"
+        return 1
+        ;;
+      *)
+        if [[ "$name" != "" ]]; then
+          echo "$fg[red]error:$reset_color invalid argument: $1"
+          return 1
+        fi
+        name=$1
+        shift
+        ;;
+    esac
+  done
+
+  if [[ "$project" != "" ]] && [[ "$name" != "" ]]; then
+    echo "$fg[red]error:$reset_color <name> not allowed with -p"
+    return 1
+  fi
+  if [[ "$project" == "" ]] && [[ "$name" == "" ]]; then
+    echo "$usage"
+    return 0
+  fi
+
+  if [[ "$host" != "" ]]; then
+    if [[ "$TMUX" != "" ]]; then
+      echo "$fg[red]error:$reset_color <host> not allowed inside tmux session"
       return 1
     fi
-    if [[ "$3" != "" ]]; then
-      echo "$fg[red]error:$reset_color invalid argument: $3"
-      return 1
+    declare -A hosts
+    if [ -f ~/.config/session ]; then
+      source ~/.config/session
+    fi
+    host=${hosts[$host]:-$host}
+  fi
+
+  if [[ "$project" != "" ]]; then
+    # tmux rewrites `.` and `:` in session names, so mirror that to keep the
+    # name we create and the name we target in sync.
+    name=${project//[.:]/_}
+    if [[ "$host" != "" ]]; then
+      # The project lives in the remote ~/Projects, so resolve it there rather
+      # than locally. The remote session-created hook reads TMUX_PROJECT back
+      # out of the remote tmux server to build the layout.
+      ssh "$host" -t "
+        repo=\$HOME/Projects/${(q)project}
+        [ -d \"\$repo\" ] ||
+          { echo 'error: no such project: ${(q)project}' >&2; exit 1; }
+        git -C \"\$repo\" rev-parse --git-dir >/dev/null 2>&1 ||
+          { echo \"error: not a git repository: \$repo\" >&2; exit 1; }
+        exec tmux new-session -As ${(q)name} -c \"\$HOME\" -e TMUX_PROJECT=${(q)project}
+      "
+      return
     fi
     local repo=$HOME/Projects/$project
     if [ ! -d "$repo" ]; then
@@ -33,9 +102,6 @@ its default branch.
       echo "$fg[red]error:$reset_color not a git repository: $repo"
       return 1
     fi
-    # tmux rewrites `.` and `:` in session names, so mirror that to keep the
-    # name we create and the name we target in sync.
-    local name=${project//[.:]/_}
     if [[ "$TMUX" == "" ]]; then
       tmux new-session -As "$name" -c $HOME -e "TMUX_PROJECT=$project"
     else
@@ -43,33 +109,13 @@ its default branch.
         tmux new-session -Ads "$name" -c $HOME -e "TMUX_PROJECT=$project"
       tmux switch-client -t "=$name"
     fi
+  elif [[ "$host" != "" ]]; then
+    ssh "$host" -t tmux new-session -As "$name"
+  elif [[ "$TMUX" == "" ]]; then
+    tmux new-session -As "$name"
   else
-    local name=$1
-    local host=$2
-    if [[ "$3" != "" ]]; then
-      echo "$fg[red]error:$reset_color invalid argument: $3"
-      return 1
-    fi
-    declare -A hosts
-    if [ -f ~/.config/session ]; then
-      source ~/.config/session
-    fi
-    local url=$hosts[$host]
-    host=${url:-$host}
-    if [[ "$TMUX" == "" ]]; then
-      local cmd="tmux new-session -As $name"
-      if [[ "$host" != "" ]]; then
-        cmd="ssh $host -t $cmd"
-      fi
-      eval $cmd
-    else
-      if [[ "$host" != "" ]]; then
-        echo "$fg[red]error:$reset_color <host> not allowed inside tmux session"
-        return 1
-      fi
-      tmux list-sessions | grep "$name:" &> /dev/null || \
-        tmux new-session -Ads $name -c $HOME
-      tmux switch-client -t $name
-    fi
+    tmux has-session -t "=$name" &> /dev/null || \
+      tmux new-session -Ads "$name" -c $HOME
+    tmux switch-client -t "=$name"
   fi
 }