#!/usr/bin/env bash
# Write the update manifest for a built APK.
#
# 🔴 The version in the manifest is read back OUT of the APK, never typed. A
# manifest that claims a version the APK is not is worse than no manifest: it
# either offers an update that installs as the same build (and so appears to do
# nothing), or fails to offer one that exists. Reading it from the artifact is
# what makes the two incapable of disagreeing.
#
# Usage: scripts/release-manifest.sh <apk> [notes] > android-latest.json
set -euo pipefail

apk="${1:?usage: release-manifest.sh <apk> [notes]}"
notes="${2:-}"

[ -f "$apk" ] || { echo "no such APK: $apk" >&2; exit 1; }

# aapt2 ships with the build tools; find the newest one rather than pinning a
# version that will be wrong on the next machine.
sdk="${ANDROID_HOME:-$HOME/Library/Android/sdk}"
aapt2="$(find "$sdk/build-tools" -maxdepth 2 -name aapt2 -type f 2>/dev/null | sort -V | tail -1)"
[ -n "$aapt2" ] || { echo "aapt2 not found under $sdk/build-tools" >&2; exit 1; }

badging="$("$aapt2" dump badging "$apk")"
code="$(sed -n "s/.*versionCode='\([0-9]*\)'.*/\1/p" <<<"$badging" | head -1)"
name="$(sed -n "s/.*versionName='\([^']*\)'.*/\1/p" <<<"$badging" | head -1)"
[ -n "$code" ] && [ -n "$name" ] || { echo "could not read version from $apk" >&2; exit 1; }

sha="$(shasum -a 256 "$apk" | cut -d' ' -f1)"

# ⚠️ No `url` field, deliberately. The client builds the download URL from the
# relay it is signed in to and ignores anything the manifest says about where
# the APK lives — a relay that could name the host could hand its users a
# different app. Adding one here would be dead weight at best and a trap for
# the next person to implement a client at worst.
cat <<JSON
{
  "versionCode": $code,
  "versionName": "$name",
  "sha256": "$sha",
  "notes": $(python3 -c 'import json,sys; print(json.dumps(sys.argv[1]))' "$notes")
}
JSON