#!/bin/sh
# lamps.sh/install — installs the `lamp` binary.
#   curl -fsSL https://lamps.sh/install | sh
#
# What it does, in order: detect OS/arch, download the release binary from GitHub,
# verify its sha256, put it in ~/.lamps/bin, tell you how to add that to PATH.
# Nothing else. Read it; it is short on purpose.
set -eu

REPO="synsema/lamp"
BASE="https://github.com/${REPO}/releases/latest/download"
LAMPS_HOME="${LAMPS_HOME:-$HOME/.lamps}"
BIN_DIR="${LAMPS_HOME}/bin"

say() { printf '%s\n' "$*"; }
die() { printf 'lamp install: %s\n' "$*" >&2; exit 1; }

os=$(uname -s | tr '[:upper:]' '[:lower:]')
case "$os" in
  linux)  os=linux ;;
  darwin) os=darwin ;;
  *) die "unsupported OS: $os (use install.ps1 on Windows)" ;;
esac

arch=$(uname -m)
case "$arch" in
  x86_64|amd64)  arch=x64 ;;
  arm64|aarch64) arch=arm64 ;;
  *) die "unsupported architecture: $arch" ;;
esac

asset="lamp-${os}-${arch}"
tmp=$(mktemp -d 2>/dev/null || mktemp -d -t lamp)
trap 'rm -rf "$tmp"' EXIT

fetch() {
  if command -v curl >/dev/null 2>&1; then curl -fsSL "$1" -o "$2"
  elif command -v wget >/dev/null 2>&1; then wget -q "$1" -O "$2"
  else die "need curl or wget"; fi
}

say "downloading ${asset} …"
fetch "${BASE}/${asset}" "${tmp}/lamp"
fetch "${BASE}/${asset}.sha256" "${tmp}/lamp.sha256"

expected=$(awk '{print $1}' "${tmp}/lamp.sha256")
if command -v sha256sum >/dev/null 2>&1; then actual=$(sha256sum "${tmp}/lamp" | awk '{print $1}')
elif command -v shasum >/dev/null 2>&1; then actual=$(shasum -a 256 "${tmp}/lamp" | awk '{print $1}')
else die "need sha256sum or shasum to verify the download"; fi
[ "$expected" = "$actual" ] || die "sha256 mismatch: expected $expected, got $actual"

mkdir -p "$BIN_DIR"
install -m 755 "${tmp}/lamp" "${BIN_DIR}/lamp" 2>/dev/null || { cp "${tmp}/lamp" "${BIN_DIR}/lamp"; chmod 755 "${BIN_DIR}/lamp"; }

say "installed ${BIN_DIR}/lamp"

case ":$PATH:" in
  *":${BIN_DIR}:"*) ;;
  *)
    shell_name=$(basename "${SHELL:-sh}")
    case "$shell_name" in
      zsh)  rc="$HOME/.zshrc" ;;
      bash) rc="$HOME/.bashrc" ;;
      fish) rc="$HOME/.config/fish/config.fish" ;;
      *)    rc="$HOME/.profile" ;;
    esac
    if [ "$shell_name" = fish ]; then
      line="set -gx PATH \$PATH ${BIN_DIR}"
    else
      line="export PATH=\"\$PATH:${BIN_DIR}\""
    fi
    if [ -w "$(dirname "$rc")" ] && ! grep -qs "$BIN_DIR" "$rc" 2>/dev/null; then
      printf '\n# lamps\n%s\n' "$line" >> "$rc"
      say "added ${BIN_DIR} to PATH in ${rc} — open a new shell, or run:"
    else
      say "add ${BIN_DIR} to your PATH:"
    fi
    say "  $line"
    ;;
esac

say ""
say "next — nothing is pulled yet; every lamp is one pull away:"
say "  lamp pull git            read-only git, from github.com/synsema/lamps"
say "  cd <a git repository>"
say "  lamp git log             runs under stdout,env=LAMP_*,exec=git — nothing else"
say "  lamp list                what is here, and whether agents get it"