#!/bin/sh
# script/bootstrap: install all dependencies needed to build and develop
# this repo. Idempotent: every install is guarded by a check so already
# installed tools are skipped. Base tooling comes from nix, apt, brew,
# or apk (detected in that order); assumes nothing is present. Node is
# used directly if installed; otherwise it is installed at a pinned
# version via nvm (installing nvm itself first, from a hash-verified
# release archive, never curl | sh).
set -eu

ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"

# Pinned versions, 2026-07-06
NODE_VERSION="22.17.0"
NVM_VERSION="0.40.3"
# sha256 of https://github.com/nvm-sh/nvm/archive/refs/tags/v0.40.3.tar.gz
NVM_SHA256="5f4d6aaa04a177dc93c985e31dbc411ab6b8c6e1e21d8015dbc1372625fcd1d0"
YARN_VERSION="1.22.22"

PKGMGR=""
SUDO=""

detect_pkgmgr() {
    [ -n "$PKGMGR" ] && return 0
    if command -v nix-env >/dev/null 2>&1; then
        PKGMGR="nix"
    elif command -v apt-get >/dev/null 2>&1; then
        PKGMGR="apt"
    elif command -v brew >/dev/null 2>&1; then
        PKGMGR="brew"
    elif command -v apk >/dev/null 2>&1; then
        PKGMGR="apk"
    else
        echo "bootstrap: no supported package manager (nix, apt, brew, apk)" >&2
        exit 1
    fi
    if [ "$PKGMGR" = "apt" ]; then
        export DEBIAN_FRONTEND=noninteractive
        if [ "$(id -u)" != "0" ]; then
            SUDO="sudo"
        fi
    fi
}

# pkg_install <nix-attr> <apt-pkg> <brew-formula> <apk-pkg>
pkg_install() {
    detect_pkgmgr
    case "$PKGMGR" in
        nix) nix-env -iA "nixpkgs.$1" ;;
        apt) $SUDO env DEBIAN_FRONTEND=noninteractive apt-get install -y "$2" ;;
        brew) brew install "$3" ;;
        apk) apk add --no-cache "$4" ;;
    esac
}

missing() {
    ! command -v "$1" >/dev/null 2>&1
}

# verify_sha256 <file> <expected-hash>
verify_sha256() {
    if command -v sha256sum >/dev/null 2>&1; then
        actual="$(sha256sum "$1" | cut -d' ' -f1)"
    else
        actual="$(shasum -a 256 "$1" | cut -d' ' -f1)"
    fi
    if [ "$actual" != "$2" ]; then
        echo "bootstrap: sha256 mismatch for $1" >&2
        echo "  expected: $2" >&2
        echo "  actual:   $actual" >&2
        exit 1
    fi
}

# nvm is a bash script; run a command in a bash with nvm loaded
nvm_sh() {
    bash -c ". \"\$HOME/.nvm/nvm.sh\" && $*"
}

ensure_nvm() {
    [ -s "$HOME/.nvm/nvm.sh" ] && return 0
    # nvm prerequisites; nvm itself requires bash
    if missing bash; then pkg_install bash bash bash bash; fi
    if missing curl; then pkg_install curl curl curl curl; fi
    if missing git; then pkg_install git git git git; fi
    tmp="$(mktemp -d)"
    curl -fsSL -o "$tmp/nvm.tar.gz" \
        "https://github.com/nvm-sh/nvm/archive/refs/tags/v${NVM_VERSION}.tar.gz"
    verify_sha256 "$tmp/nvm.tar.gz" "$NVM_SHA256"
    mkdir -p "$HOME/.nvm"
    tar -xzf "$tmp/nvm.tar.gz" -C "$HOME/.nvm" --strip-components=1
    rm -rf "$tmp"
}

ensure_node() {
    if ! missing node; then return 0; fi
    ensure_nvm
    nvm_sh "nvm install $NODE_VERSION"
}

ensure_yarn() {
    if ! missing yarn; then return 0; fi
    if ! missing corepack; then
        corepack enable
        corepack prepare "yarn@$YARN_VERSION" --activate
    elif [ -s "$HOME/.nvm/nvm.sh" ]; then
        nvm_sh "nvm use $NODE_VERSION >/dev/null && corepack enable && \
            corepack prepare yarn@$YARN_VERSION --activate"
    else
        npm install -g "yarn@$YARN_VERSION"
    fi
}

install_js_deps() {
    if missing yarn && [ -s "$HOME/.nvm/nvm.sh" ]; then
        nvm_sh "nvm use $NODE_VERSION >/dev/null && cd \"$ROOT\" && \
            yarn install --frozen-lockfile"
    else
        yarn install --frozen-lockfile
    fi
}

main() {
    cd "$ROOT"

    if missing make; then pkg_install gnumake make make make; fi
    if missing git; then pkg_install git git git git; fi

    ensure_node
    ensure_yarn
    install_js_deps

    echo "bootstrap complete"
}

main "$@"