install.sh

#!/usr/bin/env bash
# loopsmith universal installer — Linux, macOS, BSD.
#
# Detects the host, installs what is missing via the native package manager,
# builds the release binary, and puts it somewhere on PATH. Re-runnable and
# idempotent: running it twice is how you upgrade.
#
# On Windows, run install.bat instead. This script needs bash; the *generated*
# loop scripts are POSIX sh, which is a different requirement — an installer runs
# once on a machine you are sitting at, and a loop script runs unattended on a
# machine nobody chose.
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# Every fact this shares with install.ps1 comes from one file. Three copies of
# a repository URL is three chances to move the repository and fix two of them,
# and the one nobody fixes is the script for the OS they are not on.
MANIFEST="$SCRIPT_DIR/installers/manifest.json"
# shellcheck source=installers/manifest.sh
. "$SCRIPT_DIR/installers/manifest.sh"

BINARY="$(m_str binary)"
REPO_URL="${LOOPSMITH_REPO_URL:-$(m_str repo_url)}"
INSTALL_DIR="${LOOPSMITH_HOME:-$HOME/$(m_str install_dir_name)}"
BIN_LINK_DIR="${LOOPSMITH_BIN_DIR:-$(m_str unix_link_dir)}"
BRANCH="${LOOPSMITH_BRANCH:-$(m_str branch)}"
BUILD_DIR="$(m_str build_dir)"
BUILT="$(m_str built_unix)"
LOG="$INSTALL_DIR/install.log"

log()  { printf '\033[1;36m[loopsmith]\033[0m %s\n' "$*" | tee -a "$LOG" >&2; }
warn() { printf '\033[1;33m[loopsmith]\033[0m %s\n' "$*" | tee -a "$LOG" >&2; }
err()  { printf '\033[1;31m[loopsmith]\033[0m %s\n' "$*" | tee -a "$LOG" >&2; exit 1; }

detect_os() {
  case "$(uname -s | tr '[:upper:]' '[:lower:]')" in
    linux*)                    echo linux ;;
    darwin*)                   echo macos ;;
    freebsd*|openbsd*|netbsd*) echo bsd ;;
    msys*|cygwin*|mingw*)      echo windows ;;
    *)                         echo unknown ;;
  esac
}

mkdir -p "$INSTALL_DIR"
: > "$LOG"

OS="$(detect_os)"
log "host: $OS $(uname -m)"
[ "$OS" = unknown ] && err "unsupported host: $(uname -s)"
if [ "$OS" = windows ]; then
  warn "this looks like an MSYS/Cygwin shell. install.bat is the native path."
  warn "continuing, since a POSIX layer is present."
fi

DEPS_SCRIPT="$SCRIPT_DIR/installers/deps.sh"

if [ -f "$DEPS_SCRIPT" ]; then
  log "resolving dependencies"
  bash "$DEPS_SCRIPT" 2>&1 | tee -a "$LOG"
else
  warn "installers/deps.sh not found; falling back to an inline rustup install"
  if ! command -v cargo >/dev/null 2>&1; then
    curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal
    # shellcheck disable=SC1091
    . "$HOME/.cargo/env"
  fi
fi

# rustup writes its PATH line to ~/.profile, which zsh never reads, so a shell
# that has cargo installed can still not see it. Add it for this process.
[ -d "$HOME/.cargo/bin" ] && export PATH="$HOME/.cargo/bin:$PATH"
m_list requires | while read -r tool; do
  command -v "$tool" >/dev/null 2>&1 || err "$tool is required and is not on PATH after the dependency step"
done
# The loop above runs in a subshell, so its `err` cannot exit this one. Check
# the two that matter again here rather than pretending the loop was the guard.
command -v cargo >/dev/null 2>&1 || err "cargo is still not on PATH after dependency install"
command -v git   >/dev/null 2>&1 || err "git is required"

# A checkout beside this script is the source of truth when there is one; that is
# what makes `git clone && ./install.sh` install the code you just cloned rather
# than whatever main happens to be.
if [ -d "$SCRIPT_DIR/$BUILD_DIR" ]; then
  log "building from the checkout at $SCRIPT_DIR"
  SRC_DIR="$SCRIPT_DIR"
else
  log "cloning $REPO_URL ($BRANCH)"
  rm -rf "$INSTALL_DIR/src"
  git clone --depth 1 --branch "$BRANCH" "$REPO_URL" "$INSTALL_DIR/src" 2>&1 | tee -a "$LOG"
  SRC_DIR="$INSTALL_DIR/src"
fi

log "building release binary — a few minutes on a cold cache"
# `m_list` one per line into "$@", so an argument with a space stays one
# argument. `cargo build --release --bin loopsmith` is the manifest's business,
# not this script's.
set --
while IFS= read -r arg; do set -- "$@" "$arg"; done <<EOF
$(m_list build_args)
EOF
( cd "$SRC_DIR/$BUILD_DIR" && cargo "$@" ) 2>&1 | tee -a "$LOG"

BIN_SRC="$SRC_DIR/$BUILT"
BIN_DST="$INSTALL_DIR/$(m_str bin_subdir)/$BINARY"
[ -x "$BIN_SRC" ] || err "the build reported success but $BIN_SRC is not there"
mkdir -p "$(dirname "$BIN_DST")"
install -m 0755 "$BIN_SRC" "$BIN_DST"
log "installed $BIN_DST"

if [ -w "$BIN_LINK_DIR" ] || [ "$(id -u)" -eq 0 ]; then
  ln -sf "$BIN_DST" "$BIN_LINK_DIR/$BINARY"
  log "linked $BIN_LINK_DIR/$BINARY"
else
  warn "cannot write to $BIN_LINK_DIR, so nothing was linked."
  warn "add this to your shell profile:"
  warn "  export PATH=\"$(dirname "$BIN_DST"):\$PATH\""
fi

log "done. next:"
m_list next_steps | while IFS= read -r step; do log "  $step"; done