#!/usr/bin/env bash
# One-time host setup: Rust toolchain + the protoc that proto codegen needs.
# Idempotent -- safe to re-run.

source "$(dirname "${BASH_SOURCE[0]}")/lib.sh"
setup_path

info "Checking Rust toolchain"
if ! command -v rustup >/dev/null 2>&1; then
  step "rustup not found -- installing"
  curl --proto '=https' --tlsv1.2 -fsSL https://sh.rustup.rs \
    | sh -s -- -y --no-modify-path --profile default
  setup_path
else
  step "rustup $(rustup --version 2>/dev/null | head -n1)"
fi

# rust-toolchain.toml pins the exact version (and extra targets). Running rustup
# inside the tree makes it materialise that toolchain rather than the default.
TOOLCHAIN_SRC=""
for d in "$WORK_DIR" "$UPSTREAM_DIR"; do
  [[ -f "$d/rust-toolchain.toml" ]] && { TOOLCHAIN_SRC="$d"; break; }
done
if [[ -n "$TOOLCHAIN_SRC" ]]; then
  pinned="$(grep -E '^\s*channel' "$TOOLCHAIN_SRC/rust-toolchain.toml" | head -n1 | cut -d'"' -f2)"
  step "Materialising pinned toolchain ${pinned:-from rust-toolchain.toml}"
  (cd "$TOOLCHAIN_SRC" && rustup show >/dev/null)
  step "$(cd "$TOOLCHAIN_SRC" && rustc --version)"
else
  warn "no checkout yet -- pinned toolchain will be installed on first 'make apply'"
fi

# protoc: xai-grok-tools-api's build script compiles proto/grok-tools.proto.
# Upstream resolves it as $PROTOC -> ./bin/protoc (a DotSlash wrapper that
# downloads protoc 29.3) -> protoc on PATH. Satisfy path 2, fall back to 3.
info "Checking protoc"
if command -v dotslash >/dev/null 2>&1; then
  step "dotslash $(dotslash --version 2>/dev/null | head -n1)"
else
  step "dotslash not found -- installing (enables the hermetic bin/protoc)"
  cargo install dotslash || warn "cargo install dotslash failed; will fall back to a system protoc"
  setup_path
fi

probe_protoc() {
  local d="$1"
  [[ -x "$d/bin/protoc" ]] || return 1
  (cd "$d" && ./bin/protoc --version) 2>/dev/null
}

resolved=""
for d in "$WORK_DIR" "$UPSTREAM_DIR"; do
  if out="$(probe_protoc "$d")"; then
    step "hermetic bin/protoc works: $out"
    resolved=1
    break
  fi
done

if [[ -z "$resolved" ]]; then
  if command -v protoc >/dev/null 2>&1; then
    step "falling back to system protoc: $(protoc --version)"
  elif [[ -d "$WORK_DIR" || -d "$UPSTREAM_DIR" ]]; then
    step "no working protoc -- installing protobuf-compiler"
    if ! { sudo apt-get update -qq && sudo apt-get install -y -qq protobuf-compiler; }; then
      die "could not provide a protoc. Install DotSlash (https://dotslash-cli.com) or protobuf-compiler manually."
    fi
    step "system protoc: $(protoc --version)"
  else
    warn "no checkout yet -- protoc will be verified on first 'make apply'"
  fi
fi

info "Setup complete."
cat <<EOF

  Add Rust to your interactive shell if you have not already:
    fish:  source $CARGO_HOME/env.fish
    bash:  source $CARGO_HOME/env

  Next:
    make apply     # build work/ from upstream + patches
    make build     # compile the $BIN_NAME binary
EOF