#!/usr/bin/env bash

set -euo pipefail

usage()
{
	cat <<'EOF'
Usage: ./scripts/release.sh CHANNEL VERSION [OPTIONS]

Build a verified local release package in dist/vVERSION/. This command does not
commit, tag, push, create a Gitea release, or upload files.

Channels:
  stable
  prerelease (aliases: pre, beta)

Options:
  --description TEXT       Developer-written Markdown release description
  --description-file PATH  Read developer-written Markdown from PATH
  --no-auto-changelog      Omit commit-derived change notes
  --changelog-only         Write and display release notes without building
  --editor                 Edit the final notes with ${EDITOR:-nano}
  --dry-run                Build and verify in a temporary directory only
  --skip-tests             Skip configured local preflight checks
  --signing-key PATH       Use PATH instead of the local release signing key
  -h, --help               Show this help
EOF
}

if [[ $# -lt 1 ]]
then
	usage >&2
	exit 2
fi
if [[ "$1" == "-h" || "$1" == "--help" ]]
then
	usage
	exit 0
fi
if [[ $# -lt 2 ]]
then
	usage >&2
	exit 2
fi

CHANNEL_INPUT="$1"
VERSION="$2"
shift 2

case "$CHANNEL_INPUT" in
	stable)
		CHANNEL="stable"
		;;
	prerelease|pre|beta)
		CHANNEL="prerelease"
		;;
	*)
		printf 'Unsupported release channel: %s\n' "$CHANNEL_INPUT" >&2
		exit 2
		;;
esac

DESCRIPTION=""
DESCRIPTION_FILE=""
AUTO_CHANGELOG=1
CHANGELOG_ONLY=0
OPEN_EDITOR=0
DRY_RUN=0
SKIP_TESTS=0
SIGNING_KEY="${PTLINUX_SIGNING_KEY:-}"

while [[ $# -gt 0 ]]
do
	case "$1" in
		--description)
			[[ $# -ge 2 ]] || { printf '%s\n' '--description requires text.' >&2; exit 2; }
			DESCRIPTION="$2"
			shift 2
			;;
		--description-file)
			[[ $# -ge 2 ]] || { printf '%s\n' '--description-file requires a path.' >&2; exit 2; }
			DESCRIPTION_FILE="$2"
			shift 2
			;;
		--no-auto-changelog)
			AUTO_CHANGELOG=0
			shift
			;;
		--changelog-only)
			CHANGELOG_ONLY=1
			shift
			;;
		--editor)
			OPEN_EDITOR=1
			shift
			;;
		--dry-run)
			DRY_RUN=1
			shift
			;;
		--skip-tests)
			SKIP_TESTS=1
			shift
			;;
		--signing-key)
			[[ $# -ge 2 ]] || { printf '%s\n' '--signing-key requires a path.' >&2; exit 2; }
			SIGNING_KEY="$2"
			shift 2
			;;
		-h|--help)
			usage
			exit 0
			;;
		*)
			printf 'Unknown release option: %s\n' "$1" >&2
			usage >&2
			exit 2
			;;
	esac
done

if [[ -n "$DESCRIPTION" && -n "$DESCRIPTION_FILE" ]]
then
	printf '%s\n' 'Use either --description or --description-file, not both.' >&2
	exit 2
fi

SCRIPT_ROOT="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_ROOT="$(cd -- "${SCRIPT_ROOT}/.." && pwd)"
CONFIG_PATH="${PROJECT_ROOT}/release/config.json"

if [[ -n "${PTLINUX_PYTHON:-}" ]]
then
	PYTHON_BIN="$PTLINUX_PYTHON"
elif [[ -x "${PROJECT_ROOT}/.venv/bin/python" ]]
then
	PYTHON_BIN="${PROJECT_ROOT}/.venv/bin/python"
else
	PYTHON_BIN="python3"
fi

if [[ "$(git -C "$PROJECT_ROOT" rev-parse --show-toplevel 2>/dev/null || true)" != "$PROJECT_ROOT" ]]
then
	printf 'Release command is not inside the expected Git repository: %s\n' "$PROJECT_ROOT" >&2
	exit 1
fi
cd -- "$PROJECT_ROOT"

"$PYTHON_BIN" -m ptlinux.update_resolver validate "$CHANNEL" "$VERSION"
TAG="v${VERSION}"
COMMIT="$(git rev-parse HEAD)"
SOURCE_DATE_EPOCH="$(git show -s --format=%ct HEAD)"

if [[ -n "$(git status --porcelain --untracked-files=normal)" ]]
then
	printf '%s\n' \
		"Warning: packaging the current working tree on top of source commit ${COMMIT}." \
		'The signed per-file manifest records the exact packaged content.' >&2
fi

if [[ -n "$DESCRIPTION_FILE" && ! -f "$DESCRIPTION_FILE" ]]
then
	printf 'Release description file does not exist: %s\n' "$DESCRIPTION_FILE" >&2
	exit 1
fi

TEMPORARY_ROOT="$(mktemp -d)"
cleanup()
{
	rm -rf -- "$TEMPORARY_ROOT"
}
trap cleanup EXIT
NOTES_PATH="${TEMPORARY_ROOT}/release-notes.md"

if [[ -z "$DESCRIPTION" && -z "$DESCRIPTION_FILE" && -t 0 && "$CHANGELOG_ONLY" -eq 0 ]]
then
	printf '%s\n' 'Release description' '-------------------' '' \
		'Enter release notes. Finish with Ctrl+D.' ''
	DESCRIPTION_FILE="${TEMPORARY_ROOT}/description.md"
	cat < /dev/tty > "$DESCRIPTION_FILE"
fi

{
	printf '# PristonTale EU Launcher %s\n\n' "$VERSION"
	if [[ -n "$DESCRIPTION" ]]
	then
		printf '%s\n\n' "$DESCRIPTION"
	elif [[ -n "$DESCRIPTION_FILE" ]]
	then
		cat -- "$DESCRIPTION_FILE"
		if [[ -s "$DESCRIPTION_FILE" && "$(tail -c 1 -- "$DESCRIPTION_FILE" | wc -l)" -eq 0 ]]
		then
			printf '\n'
		fi
		printf '\n'
	fi
	if [[ "$AUTO_CHANGELOG" -eq 1 ]]
	then
		mapfile -t RELEASE_TAGS < <(git tag --merged HEAD)
		PREVIOUS_TAG="$(
			"$PYTHON_BIN" -m ptlinux.update_resolver previous-tag \
				"$CHANNEL" "$VERSION" "${RELEASE_TAGS[@]}"
		)"
		printf '## Changes\n\n'
		if [[ -n "$PREVIOUS_TAG" ]]
		then
			CHANGELOG_RANGE="${PREVIOUS_TAG}..HEAD"
		else
			CHANGELOG_RANGE="HEAD"
		fi
		CHANGELOG="$(git log "$CHANGELOG_RANGE" --no-merges --pretty=format:'- %s (`%h`)')"
		if [[ -n "$CHANGELOG" ]]
		then
			printf '%s\n' "$CHANGELOG"
		else
			printf '%s\n' '- No commits since the previous release.'
		fi
		printf '\n'
	fi
	printf '%s\n' '---' '' \
		"Version: \`${VERSION}\`  " \
		"Channel: \`${CHANNEL}\`  " \
		"Tag: \`${TAG}\`  " \
		"Source commit: \`${COMMIT}\`"
} > "$NOTES_PATH"

if [[ "$OPEN_EDITOR" -eq 1 ]]
then
	EDITOR_COMMAND="${EDITOR:-nano}"
	"$EDITOR_COMMAND" "$NOTES_PATH"
fi

printf '%s\n' '--------------------------------------------------' 'Release Notes' \
	'--------------------------------------------------'
cat -- "$NOTES_PATH"
printf '%s\n' '--------------------------------------------------'

if [[ "$CHANGELOG_ONLY" -eq 1 ]]
then
	NOTES_OUTPUT_DIRECTORY="${PROJECT_ROOT}/dist/${TAG}"
	mkdir -p -- "$NOTES_OUTPUT_DIRECTORY"
	cp -- "$NOTES_PATH" "${NOTES_OUTPUT_DIRECTORY}/release-notes.md"
	printf 'Release notes written to %s\n' \
		"${NOTES_OUTPUT_DIRECTORY}/release-notes.md"
	exit 0
fi

if [[ "$SKIP_TESTS" -ne 1 ]]
then
	mapfile -t PREFLIGHT_COMMANDS < <(
		"$PYTHON_BIN" -c \
			'import json,sys; value=json.load(open(sys.argv[1],encoding="utf-8")); print("\n".join(value["preflight"]))' \
			"$CONFIG_PATH"
	)
	for PREFLIGHT_COMMAND in "${PREFLIGHT_COMMANDS[@]}"
	do
		printf 'Preflight: %s\n' "$PREFLIGHT_COMMAND"
		PTLINUX_PYTHON="$PYTHON_BIN" bash -o pipefail -c "$PREFLIGHT_COMMAND" \
			< /dev/null
	done
else
	printf '%s\n' 'Skipping local preflight checks by request.'
fi

if [[ -z "$SIGNING_KEY" ]]
then
	SIGNING_KEY="${PROJECT_ROOT}/release-keys/launcher-update-private.pem"
fi
if [[ ! -f "$SIGNING_KEY" || -L "$SIGNING_KEY" ]]
then
	printf 'Release signing key is missing: %s\n' "$SIGNING_KEY" >&2
	printf '%s\n' 'Use --signing-key PATH or set PTLINUX_SIGNING_KEY.' >&2
	exit 1
fi

if [[ "$DRY_RUN" -eq 1 ]]
then
	OUTPUT_DIRECTORY="${TEMPORARY_ROOT}/dist/${TAG}"
else
	OUTPUT_DIRECTORY="${PROJECT_ROOT}/dist/${TAG}"
fi

SOURCE_DATE_EPOCH="$SOURCE_DATE_EPOCH" \
RELEASE_COMMIT="$COMMIT" \
RELEASE_TAG="$TAG" \
RELEASE_NOTES_FILE="$NOTES_PATH" \
PTLINUX_PYTHON="$PYTHON_BIN" \
PTLINUX_SIGNING_KEY="$SIGNING_KEY" \
REQUIRE_RELEASE_SIGNATURE=1 \
ALLOW_SOURCE_VERSION_OVERRIDE=1 \
	"${SCRIPT_ROOT}/build-release.sh" "$VERSION" "$CHANNEL" "$OUTPUT_DIRECTORY"

PTLINUX_PYTHON="$PYTHON_BIN" \
REQUIRE_RELEASE_SIGNATURE=1 \
	"${SCRIPT_ROOT}/verify-release.sh" "$VERSION" "$CHANNEL" "$OUTPUT_DIRECTORY"

if [[ "$DRY_RUN" -eq 1 ]]
then
	printf '%s\n' \
		'Dry run complete. The release built and verified in a temporary directory; dist/ was not changed.'
	exit 0
fi

mkdir -p -- "${OUTPUT_DIRECTORY}/channel"
cp -- "${OUTPUT_DIRECTORY}/manifest.json" \
	"${OUTPUT_DIRECTORY}/channel/${CHANNEL}.json"
cp -- "${OUTPUT_DIRECTORY}/manifest.json.sig" \
	"${OUTPUT_DIRECTORY}/channel/${CHANNEL}.json.sig"

mapfile -t PACKAGE_METADATA < <(
	"$PYTHON_BIN" -c \
		'import json,sys; value=json.load(open(sys.argv[1], encoding="utf-8")); archive=value["archive"]; print(archive["layout"]); print(value["minimum_updater_version"]); print(archive["size"]); print(archive["sha256"]); print(archive["url"])' \
		"${OUTPUT_DIRECTORY}/manifest.json"
)
ARCHIVE_LAYOUT="${PACKAGE_METADATA[0]}"
MINIMUM_UPDATER_VERSION="${PACKAGE_METADATA[1]}"
ARCHIVE_SIZE="${PACKAGE_METADATA[2]}"
ARCHIVE_SHA256="${PACKAGE_METADATA[3]}"
ARCHIVE_URL="${PACKAGE_METADATA[4]}"

if [[ "$CHANNEL" == "prerelease" ]]
then
	PRERELEASE_INSTRUCTION='select the Gitea "Pre-release" checkbox'
else
	PRERELEASE_INSTRUCTION='leave the Gitea "Pre-release" checkbox clear'
fi

printf '\nManual Gitea release package is ready in %s\n' "$OUTPUT_DIRECTORY"
printf 'Create tag/release: %s\n' "$TAG"
printf 'Release type: %s; %s.\n' "$CHANNEL" "$PRERELEASE_INSTRUCTION"
printf 'Archive layout: %s.\n' "$ARCHIVE_LAYOUT"
printf 'Minimum updater: %s.\n' "$MINIMUM_UPDATER_VERSION"
printf 'Archive size: %s bytes.\n' "$ARCHIVE_SIZE"
printf 'Archive SHA256: %s\n' "$ARCHIVE_SHA256"
printf 'Signed archive URL: %s\n' "$ARCHIVE_URL"
if [[ "$ARCHIVE_LAYOUT" == "wrapped" ]]
then
	printf '%s\n' \
		'Compatibility: legacy bridge archive; older launchers can install it automatically.'
else
	printf '%s\n' \
		'Compatibility: flat archive; launchers older than the minimum require a bridge release or installer update.'
fi
printf '%s\n' 'Upload these five files:' \
	"  ${OUTPUT_DIRECTORY}/PristonTale-EU-${VERSION}.tar.gz" \
	"  ${OUTPUT_DIRECTORY}/PristonTale-EU-${VERSION}.tar.gz.sha256" \
	"  ${OUTPUT_DIRECTORY}/manifest.json" \
	"  ${OUTPUT_DIRECTORY}/manifest.json.sig" \
	"  ${OUTPUT_DIRECTORY}/release-notes.md"
printf '%s\n' \
	'Wait for every upload to finish and confirm the archive has the exact nonzero size above.' \
	'Publish the channel files only after all five Gitea attachments are present.'
printf 'Channel files ready for a later repository update: %s/channel/%s.json{,.sig}\n' \
	"$OUTPUT_DIRECTORY" "$CHANNEL"
printf '%s\n' 'No commit, tag, push, Gitea release, or upload was performed.'