#!/bin/sh
# sessions wrapped — your year with AI coding agents, no install needed.
#
#   curl -fsSL https://sessions.engineering/wrapped | sh
#   curl -fsSL https://sessions.engineering/wrapped | sh -s -- --year 2025
#
# What this script does, in order:
#   1. Picks the prebuilt binary for your OS and CPU (macOS or Linux, arm64 or x86_64).
#   2. Downloads it from the project's GitHub release and checks it against that
#      release's checksums.txt. It refuses to run anything that does not match.
#   3. Keeps it in ~/.cache/sessions/bin/<version>, so a second run skips the download.
#   4. Runs `sessions wrapped`, which reads the transcripts your agents already left on
#      disk, builds a local search index in ~/.cache/sessions, and opens the result in
#      your browser. Nothing is uploaded. Unlike an installed `sessions`, this one-off
#      run does not copy your transcripts into the archive (SESSIONS_ARCHIVE=0).
#   5. Says how much it cached and how to delete it.
#
# Pin a version with SESSIONS_VERSION=v1.32.0. Source: https://github.com/nicknisi/sessions

set -eu

REPO=nicknisi/sessions

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

sha256() {
  if command -v sha256sum >/dev/null 2>&1; then
    sha256sum "$1" | awk '{print $1}'
  elif command -v shasum >/dev/null 2>&1; then
    shasum -a 256 "$1" | awk '{print $1}'
  else
    die "need sha256sum or shasum to verify the download"
  fi
}

# Everything runs from main, called on the last line: `curl | sh` feeds this script
# through stdin, and sh must have read all of it before anything it starts can touch stdin.
main() {
  case "$(uname -s)" in
    Darwin) os=darwin ;;
    Linux) os=linux ;;
    *) die "no prebuilt binary for $(uname -s) yet. Build from source: https://github.com/$REPO#from-source" ;;
  esac
  case "$(uname -m)" in
    arm64 | aarch64) arch=arm64 ;;
    x86_64 | amd64) arch=x86_64 ;;
    *) die "no prebuilt binary for $(uname -m) yet. Build from source: https://github.com/$REPO#from-source" ;;
  esac
  # An Apple-silicon Mac running this shell under Rosetta reports x86_64; prefer native.
  if [ "$os" = darwin ] && [ "$arch" = x86_64 ] && [ "$(sysctl -n sysctl.proc_translated 2>/dev/null || echo 0)" = 1 ]; then
    arch=arm64
  fi

  tag=${SESSIONS_VERSION:-}
  if [ -z "$tag" ]; then
    # /releases/latest redirects to /releases/tag/<tag>; no API call, so no rate limit.
    url=$(curl -fsSLI -o /dev/null -w '%{url_effective}' "https://github.com/$REPO/releases/latest") ||
      die "could not reach GitHub to find the latest release"
    tag=${url##*/}
  fi
  case "$tag" in v*) ;; *) tag="v$tag" ;; esac
  # The tag becomes part of a path below, so only v, digits and dots get through.
  case "$tag" in v | *[!v0-9.]*) die "not a release version: $tag" ;; esac

  asset="sessions-$os-$arch.tar.gz"
  bindir="${SESSIONS_CACHE_DIR:-$HOME/.cache/sessions}/bin"
  bin="$bindir/$tag/sessions"

  if [ ! -x "$bin" ]; then
    mkdir -p "$bindir"
    tmp=$(mktemp -d "$bindir/.download.XXXXXX")
    trap 'rm -rf "$tmp"' EXIT
    trap 'exit 130' INT TERM
    base="https://github.com/$REPO/releases/download/$tag"
    # Checksums first: a few bytes, and no point fetching 26 MB we would refuse to run.
    curl -fsL -o "$tmp/checksums.txt" "$base/checksums.txt" ||
      die "release $tag has no checksums.txt, so a download cannot be verified. Try SESSIONS_VERSION with a newer release."
    want=$(awk -v f="$asset" '$2 == f || $2 == "*" f { print $1 }' "$tmp/checksums.txt")
    [ -n "$want" ] || die "checksums.txt in $tag has no entry for $asset"
    say "downloading sessions $tag for $os-$arch"
    curl -fSL --progress-bar -o "$tmp/$asset" "$base/$asset" || die "download failed: $base/$asset"
    got=$(sha256 "$tmp/$asset")
    [ "$want" = "$got" ] || die "checksum mismatch for $asset (expected $want, got $got); not running it"
    tar -xzf "$tmp/$asset" -C "$tmp" sessions
    chmod +x "$tmp/sessions"
    mkdir -p "$bindir/$tag"
    mv "$tmp/sessions" "$bin"
    rm -rf "$tmp"
    trap - EXIT INT TERM
    # Each binary is ~65 MB; keep only the version just installed. Only folders this
    # script made (a version name holding a sessions binary) are ever removed.
    for old in "$bindir"/v[0-9]*; do
      [ "$old" != "$bindir/$tag" ] && [ -f "$old/sessions" ] && rm -rf "$old"
    done
  fi

  status=0
  SESSIONS_ARCHIVE=0 "$bin" wrapped "$@" || status=$?
  cache="${SESSIONS_CACHE_DIR:-$HOME/.cache/sessions}"
  size=$(du -sh "$cache" 2>/dev/null | awk '{print $1}')
  say "cached ${size:-some files} in $cache so a re-run is fast. Remove it any time: rm -rf '$cache'"
  say "search and agent memory over these sessions: brew install nicknisi/formulae/sessions"
  return "$status"
}

main "$@"