#!/usr/bin/env bash
#
# fdroid-publish.sh — build a signed release APK and add it to an F-Droid repo.
#
# Usage:
#   FDROID_REPO_URL=https://fdroid.example.com/repo \
#     ./scripts/fdroid-publish.sh --init-keystore ~/fdroid-mtgc     # first time
#   ./scripts/fdroid-publish.sh ~/fdroid-mtgc                       # every release after
#
# Or through npm: `npm run android:publish -- ~/fdroid-mtgc`.
#
# Options:
#   --init-keystore   generate the app signing key (once, ever) and keystore.properties
#   --allow-dirty     publish uncommitted changes; the version gets a -dirty suffix
#
# Environment:
#   MTGC_FDROID_DIR   repo directory, if not given as an argument
#   FDROID_REPO_URL   public address of <dir>/repo, ending in /repo; needed the first time,
#                     and changes the repo's address if set later
#   MTGC_ANDROID_KEYSTORE  where --init-keystore puts the key (default ~/.local/share/mtgc/android-release.jks)
#
# Serve <dir>/repo (and <dir>/archive if you like), never <dir> itself: it holds
# the repo signing key and its password. Needs fdroidserver (`pipx install
# fdroidserver`) and the Android setup from ./scripts/android-setup.sh.
#
set -euo pipefail

usage() {
    sed -n '3,24p' "$0" | sed 's/^# \{0,1\}//'
    exit "${1:-0}"
}

info() { printf '\033[1;34m==>\033[0m %s\n' "$*"; }
warn() { printf '\033[1;33m[warn]\033[0m %s\n' "$*"; }
err()  { printf '\033[1;31m[err]\033[0m %s\n' "$*" >&2; }

APP_ID="com.garrettmills.mtgc"
APP_KEYSTORE="${MTGC_ANDROID_KEYSTORE:-$HOME/.local/share/mtgc/android-release.jks}"
APP_KEY_ALIAS="mtgc"

init_keystore=false
allow_dirty=false
dir="${MTGC_FDROID_DIR:-}"
while [ $# -gt 0 ]; do
    case "$1" in
        --init-keystore) init_keystore=true ;;
        --allow-dirty) allow_dirty=true ;;
        -h | --help) usage ;;
        -*) usage 1 ;;
        *) dir="$1" ;;
    esac
    shift
done
[ -n "$dir" ] || usage 1
mkdir -p "$dir"
dir="$(cd "$dir" && pwd)"

repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
cd "$repo_root"
key_props="src-tauri/gen/android/keystore.properties"

# --- 1. Tools ---------------------------------------------------------------

source scripts/android-env.sh >/dev/null

if ! command -v fdroid >/dev/null 2>&1; then
    err "fdroid not found. Install fdroidserver: pipx install fdroidserver"
    exit 1
fi
build_tools="$(find "$ANDROID_HOME/build-tools" -mindepth 1 -maxdepth 1 -type d 2>/dev/null | sort -V | tail -1)"
apksigner="$build_tools/apksigner"
if [ ! -x "$apksigner" ]; then
    err "apksigner not found under $ANDROID_HOME/build-tools (install a build-tools package)"
    exit 1
fi

# --- 2. App signing key -----------------------------------------------------
#
# Every update must be signed with the same key as the installed app, so this
# key is made once and kept forever. Lose it, and each phone has to uninstall
# the app before it will take a newer build.

if $init_keystore; then
    if [ -e "$APP_KEYSTORE" ] || [ -e "$key_props" ]; then
        err "a signing key already exists ($APP_KEYSTORE or $key_props); not overwriting it"
        exit 1
    fi
    info "generating the app signing key at $APP_KEYSTORE"
    mkdir -p "$(dirname "$APP_KEYSTORE")"
    password="$(openssl rand -hex 24)"
    keytool -genkeypair -keystore "$APP_KEYSTORE" -storetype PKCS12 \
        -storepass "$password" -alias "$APP_KEY_ALIAS" \
        -keyalg RSA -keysize 4096 -validity 10000 -dname "CN=mtgc" >/dev/null
    chmod 600 "$APP_KEYSTORE"
    (
        umask 077
        printf 'storeFile=%s\npassword=%s\nkeyAlias=%s\n' "$APP_KEYSTORE" "$password" "$APP_KEY_ALIAS" >"$key_props"
    )
    warn "Back up $APP_KEYSTORE and $key_props (it holds the password)."
    warn "Without them, phones can't update the app without uninstalling it first."
elif [ ! -f "$key_props" ]; then
    err "no app signing key ($key_props). Run once with --init-keystore."
    exit 1
fi

# --- 3. Version -------------------------------------------------------------
#
# The versionCode is the commit count, so every commit on main can ship with no
# manual bump and F-Droid sees each one as newer than the last.

source scripts/lib/release-version.sh
version_code="$release_count"
version_name="$release_version"
if $release_dirty; then
    if ! $allow_dirty; then
        err "the working tree has uncommitted changes; commit them or pass --allow-dirty"
        exit 1
    fi
    version_name="$version_name-dirty"
fi

# --- 4. The repo, the first time --------------------------------------------

repo_url="${FDROID_REPO_URL:-}"
repo_url="${repo_url%/}"
case "$repo_url" in
    "" | */repo) ;;
    *) err "FDROID_REPO_URL must end in /repo (fdroidserver requires it), e.g. $repo_url/repo"; exit 1 ;;
esac

if [ ! -f "$dir/config.yml" ]; then
    if [ -z "$repo_url" ]; then
        err "no F-Droid repo in $dir yet; set FDROID_REPO_URL to the address $dir/repo will be served at"
        exit 1
    fi
    info "creating the F-Droid repo in $dir"
    (cd "$dir" && fdroid init --android-home "$ANDROID_HOME" --no-prompt -q)
    cat >>"$dir/config.yml" <<EOF

repo_url: $repo_url
repo_name: mtgc
repo_description: >-
  Releases of mtgc, a personal Magic: The Gathering library catalog.
archive_older: 3
EOF
    # `fdroid update` copies this into repo/icons/ itself.
    cp src-tauri/icons/icon.png "$dir/icon.png"
fi
# A later FDROID_REPO_URL moves the repo to a new address.
if [ -n "$repo_url" ] && ! grep -qxF "repo_url: $repo_url" "$dir/config.yml"; then
    info "setting repo_url to $repo_url"
    sed -i "s|^repo_url:.*|repo_url: $repo_url|" "$dir/config.yml"
fi

if [ ! -f "$dir/metadata/$APP_ID.yml" ]; then
    mkdir -p "$dir/metadata"
    cat >"$dir/metadata/$APP_ID.yml" <<'EOF'
Categories:
  - Games
License: MIT
AuthorName: Garrett Mills
SourceCode: https://code.garrettmills.dev/garrettmills/mtgc

Name: mtgc
Summary: 'Personal Magic: The Gathering library catalog'
Description: |-
  Catalog your Magic: The Gathering collection: rapid fuzzy card entry, rich
  search (colors, commander color identity, mana value, type, price, format
  legality) and deck organization. Works offline, and syncs between devices
  through an mtgc sync server.
EOF
fi
# Release builds shorten resource paths, so `fdroid update` can't find the
# launcher icon inside the APK; hand it over as metadata instead.
if [ ! -f "$dir/metadata/$APP_ID/en-US/icon.png" ]; then
    mkdir -p "$dir/metadata/$APP_ID/en-US"
    cp src-tauri/icons/icon.png "$dir/metadata/$APP_ID/en-US/icon.png"
fi

# --- 5. Only ever move forward ----------------------------------------------

newest=0
for apk in "$dir"/repo/"${APP_ID}"_*.apk "$dir"/archive/"${APP_ID}"_*.apk; do
    [ -e "$apk" ] || continue
    code="${apk##*_}"
    code="${code%.apk}"
    [ "$code" -gt "$newest" ] && newest="$code"
done
if [ "$version_code" -le "$newest" ]; then
    err "versionCode $version_code is not newer than $newest, already in the repo; commit something first"
    exit 1
fi

# --- 6. Build ---------------------------------------------------------------

info "building $version_name (versionCode $version_code)"
outputs="src-tauri/gen/android/app/build/outputs/apk/universal/release"
rm -rf "$outputs"
cargo tauri android build --apk --target aarch64 --ci \
    --config "{\"version\":\"$version_name\",\"bundle\":{\"android\":{\"versionCode\":$version_code}}}"

apk="$(find "$outputs" -name '*.apk' | head -1)"
if [ -z "$apk" ]; then
    err "the build produced no APK under $outputs"
    exit 1
fi
case "$apk" in
    *unsigned*) err "the APK came out unsigned; check $key_props"; exit 1 ;;
esac
"$apksigner" verify "$apk"

# --- 7. Publish -------------------------------------------------------------

published="$dir/repo/${APP_ID}_${version_code}.apk"
cp "$apk" "$published"
info "updating the repo index"
if ! (cd "$dir" && fdroid update -q); then
    # Take the APK back out, or the next run would think it's already published.
    rm -f "$published"
    err "fdroid update failed; nothing was published"
    exit 1
fi

# --- 8. Where to point F-Droid ----------------------------------------------

cfg() { sed -n "s/^$1: *//p" "$dir/config.yml" | head -1; }
fingerprint="$(keytool -list -v -keystore "$dir/$(cfg keystore)" -storepass "$(cfg keystorepass)" \
    -alias "$(cfg repo_keyalias)" | sed -n 's/^[[:space:]]*SHA256: *//p' | tr -d ':')"

info "published $version_name"
cat <<EOF

Serve $dir/repo at $(cfg repo_url)
(not $dir itself — it holds the repo signing key). Add this to F-Droid:

    $(cfg repo_url)?fingerprint=$fingerprint
EOF