#!/bin/bash

# omarchy:summary=Install the Hermes CLI as a mise-backed wrapper in ~/.local/bin
# omarchy:args=[--check|--now|--owns]
# omarchy:examples=omarchy install hermes cli | omarchy install hermes cli --now

# Hermes pins every one of its dependencies exactly and declares
# Requires-Python >=3.11,<3.14, so it can neither be built against Arch's
# Python nor share the python-* packages. mise builds it a private environment
# instead.
#
# It gets its own installer rather than a line in omarchy-mise-install because
# of the interpreter pin. Given no compatible interpreter to hand, uv builds
# the venv against the system Python in violation of Hermes' own bound,
# reports success, and leaves the breakage to surface later inside a
# dependency -- and omarchy-mise-install writes a fixed stub with nowhere to
# say otherwise.
#
# There is only ever one Hermes on a machine. hermes-desktop cannot run against
# this one -- it needs a runtime built from its own commit, and the version gap
# fails its readiness probe -- so it installs its own under ~/.hermes and puts
# that on PATH. When the package is present it therefore owns Hermes outright:
# this installer stands aside and removes its own copy, so the terminal, the
# default agent and the app are all the same installation.

set -euo pipefail

mode=${1:-}

tool='pipx:hermes-agent[extras=all]'
python='3.13'

# The line that identifies the stub as this installer's; matched whole, so a
# wrapper that merely mentions the command is not mistaken for ours.
marker='# Written by omarchy-install-hermes-cli.'

# The package, not the runtime directory: it is installed before the app has
# ever run, and that is exactly when we must not start building a second copy.
desktop_owns_hermes() {
  omarchy-pkg-present hermes-desktop
}

# The venv appears at the python-deps stage, several stages before the one that
# installs the command, so its presence says nothing about being usable. The
# marker is written last, and the command is what the agent actually runs.
desktop_hermes_ready() {
  [[ -f $HOME/.hermes/hermes-agent/.hermes-bootstrap-complete ]] || return 1

  # An executable of that name proves nothing about whose it is; the app's own
  # points into ~/.hermes, and anything else is not the install we are asking
  # about. Matched as a plain string, because the path carries a dot and an
  # unanchored pattern would also claim a wrapper pointing at ~/xhermes.
  [[ -f $HOME/.local/bin/hermes ]] || return 1
  grep -qF "$HOME/.hermes" "$HOME/.local/bin/hermes" || return 1

  # And a marker left behind by an install whose venv has since gone answers
  # for nothing, so the command has to run, exactly as a foreign one must.
  hermes_prompt_ready
}

# Whether Hermes is really installed, not merely whether the stub exists. A
# stub on its own is cold: running it installs Hermes, which takes minutes.
installed() {
  [[ -d "$(mise where "$tool" 2>/dev/null)/hermes-agent/lib/python$python" ]]
}

# The stub is the only thing this installer owns. Anything else at that path
# -- Hermes' official installer, a hand-rolled wrapper, even a dangling link
# -- was put there by the user and is never deleted or overwritten here.
# Symlinks count as foreign even when they resolve to a marked file: the stub
# is written as a regular file, so a link is someone else's arrangement.
ours() {
  [[ -f $HOME/.local/bin/hermes && ! -L $HOME/.local/bin/hermes ]] &&
    grep -qxF "$marker" "$HOME/.local/bin/hermes"
}

foreign_hermes() {
  [[ -e $HOME/.local/bin/hermes || -L $HOME/.local/bin/hermes ]] && ! ours
}

# A hermes at that path is usable when it is a command that runs: a regular
# executable whose --version answers. The executable bit alone proves little -- a directory
# passes -x on search permission, and a wrapper whose interpreter or target is
# gone passes it too. The desktop app applies the same probe with the same 15
# second budget, so what passes here is what it will use.
hermes_runs() {
  [[ -f $HOME/.local/bin/hermes && -x $HOME/.local/bin/hermes ]] &&
    timeout 15 "$HOME/.local/bin/hermes" --version >/dev/null 2>&1
}

# The chat subcommand's --oneshot opt-out arrived with native interactive -q,
# so its presence is a stable capability check without relying on a version.
hermes_prompt_ready() {
  local help
  hermes_runs &&
    help=$(timeout 15 "$HOME/.local/bin/hermes" chat --help 2>/dev/null) &&
    grep -qF -- '--oneshot' <<<"$help"
}

# --owns answers whether the wrapper on PATH is the one this command wrote, so
# the migration and Remove Preinstalls do not each carry their own copy of the
# marker and drift from it.
if [[ $mode == "--owns" ]]; then
  if ours; then exit 0; else exit 1; fi
fi

# --check lets callers tell a cold stub from a working one before they commit
# to a path that assumes Hermes is ready.
if [[ $mode == "--check" ]]; then
  if desktop_owns_hermes; then
    if desktop_hermes_ready; then exit 0; else exit 1; fi
  fi
  # A foreign command is ready only when it also supports prompted sessions;
  # since it is not ours to replace, nothing this installer does will update it.
  if foreign_hermes; then
    if hermes_prompt_ready; then exit 0; else exit 1; fi
  fi
  if installed && hermes_prompt_ready; then exit 0; else exit 1; fi
fi

# Hand Hermes over to the app rather than keeping a second copy beside it.
if desktop_owns_hermes; then
  # Not gated on that copy being healthy: `mise up` can rebuild it against the
  # wrong interpreter and a half-finished install answers to neither test, and
  # either way it is still a second Hermes. Removing nothing is harmless.
  if mise where "$tool" >/dev/null 2>&1; then
    echo "Hermes Desktop provides Hermes; removing the separate CLI install..." >&2
  fi

  mise rm -g "$tool" >/dev/null 2>&1 || true
  mise uninstall --all "$tool" >/dev/null 2>&1 || true

  # Our own stub has to go with it. Left in place it still answers `hermes`
  # until the app's bootstrap overwrites it, and answering means building the
  # second Hermes this whole arrangement exists to avoid.
  if ours; then
    rm -f "$HOME/.local/bin/hermes"
  fi

  if desktop_hermes_ready; then
    exit 0
  fi

  echo "Hermes Desktop is installed but has not set Hermes up yet." >&2
  echo "Launch Hermes Desktop once to finish installing it." >&2
  exit 1
fi

# The user already has a hermes of their own. Leave it be: a working one is
# what the default agent will run, and a broken one is theirs to fix.
if foreign_hermes; then
  if hermes_prompt_ready; then
    exit 0
  fi

  if hermes_runs; then
    echo "~/.local/bin/hermes does not support the interactive seeded sessions Omarchy needs." >&2
    echo "Update it to a Hermes Agent release with interactive chat queries, then run omarchy-install-hermes-cli again." >&2
    exit 1
  fi

  echo "~/.local/bin/hermes exists but is not runnable, and it was not installed by Omarchy." >&2
  echo "Fix or remove it, then run omarchy-install-hermes-cli again." >&2
  exit 1
fi

# Only the marked wrapper proves the matching mise environment is ours to replace.
if installed && ! hermes_prompt_ready; then
  if ours; then
    echo "Updating Hermes for prompted sessions..." >&2
    mise rm -g "$tool" >/dev/null 2>&1 || true
    mise uninstall --all "$tool" >/dev/null 2>&1 || true
  else
    echo "A Hermes mise environment exists without an Omarchy-owned wrapper." >&2
    echo "Update or remove it explicitly, then run omarchy-install-hermes-cli again." >&2
    exit 1
  fi
fi

mkdir -p "$HOME/.local/bin"
rm -f "$HOME/.local/bin/hermes"

cat >"$HOME/.local/bin/hermes" <<EOF
#!/bin/bash

$marker

export UV_PYTHON="$python"

# Exported rather than set on the install line alone, so the version resolved
# to run agrees with the one just installed. Hermes ships several times a week
# and mise's cooldown would otherwise hold a new release back for days.
export MISE_MINIMUM_RELEASE_AGE=0

# mise up -- which omarchy update runs -- reinstalls without that pin, so this
# asks which interpreter is actually there rather than whether anything is.
if ! [[ -d "\$(mise where '$tool' 2>/dev/null)/hermes-agent/lib/python$python" ]]; then
  echo "Installing Hermes on Python $python (this takes a minute)..." >&2

  # mise's pipx backend shells out to uv, which a stock Omarchy does not have.
  # It is fetched here rather than when this stub was written, so setting up a
  # machine that never runs Hermes costs nothing.
  if omarchy-cmd-missing uv && ! mise where uv >/dev/null 2>&1; then
    mise use -g --quiet uv@latest || exit 1
  fi

  mise use -g --quiet --force '$tool' || exit 1
fi

# The pin belongs to building Hermes, not to everything Hermes then runs.
# Exported it would reach the agent and every command it shells out to, so a
# uv in the user's own project would resolve 3.13 there too -- uv only warns
# when that contradicts the project's requires-python, and builds it anyway.
exec env -u UV_PYTHON mise x '$tool' -- hermes "\$@"
EOF

chmod +x "$HOME/.local/bin/hermes"

# The desktop app resolves a hermes on PATH by running `hermes --version` with
# a 15 second budget, then falls back to cloning its own copy when that times
# out. A first-run mise install does not fit in 15 seconds, so anything that
# hands Hermes to the GUI has to install it here rather than leave it stubbed.
if [[ $mode == "--now" ]]; then
  "$HOME/.local/bin/hermes" --version
  if ! hermes_prompt_ready; then
    echo "Hermes installed without the interactive seeded sessions Omarchy needs." >&2
    exit 1
  fi
fi