#!/usr/bin/env bash
# Copyright 2022-2024 LiveKit, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# LiveKit CLI installer for Linux. Downloads the latest GitHub release archive
# and installs the binary + completions system-wide.

set -u
set -o errtrace
set -o errexit
set -o pipefail

REPO="livekit-cli"
BIN_NAME="lk"
INSTALL_PATH="/usr/local/bin"
BASH_COMPLETION_PATH="/usr/share/bash-completion/completions"
ZSH_COMPLETION_PATH="/usr/share/zsh/site-functions"
FISH_COMPLETION_PATH="/usr/share/fish/vendor_completions.d"

log()   { printf "%b\n" "$*"; }
abort() { printf "%s\n" "$@" >&2; exit 1; }

[ -n "${BASH_VERSION:-}" ] || abort "This script requires bash"
[ -d "$INSTALL_PATH" ]     || abort "Could not install, $INSTALL_PATH doesn't exist"
command -v curl >/dev/null || abort "cURL is required and is not found"
command -v sha256sum >/dev/null || abort "sha256sum is required and is not found"

OS="$(uname)"
case "$OS" in
  Darwin) abort "Installer not supported on MacOS, please install using Homebrew." ;;
  Linux)  ;;
  *)      abort "Installer is only supported on Linux." ;;
esac

case "$(uname -m)" in
  x86_64)  ARCH="amd64" ;;
  aarch64) ARCH="arm64" ;;
  *)       abort "Unsupported architecture: $(uname -m)" ;;
esac

SUDO_PREFIX=""
if [ ! -w "$INSTALL_PATH" ]; then
  SUDO_PREFIX="sudo"
  log "sudo is required to install to $INSTALL_PATH"
fi

VERSION=$(curl -fsSL https://api.github.com/repos/livekit/$REPO/releases/latest \
  | jq -r '.tag_name' | sed 's/^v//')

[[ "$VERSION" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]] || abort "Invalid version: $VERSION"

ARCHIVE_NAME="${BIN_NAME}_${VERSION}_linux_${ARCH}.tar.gz"
ARCHIVE_URL="https://github.com/livekit/$REPO/releases/download/v${VERSION}/${ARCHIVE_NAME}"
CHECKSUMS_URL="https://github.com/livekit/$REPO/releases/download/v${VERSION}/checksums.txt"

log "Installing $REPO $VERSION"
log "Downloading from $ARCHIVE_URL..."

TEMP_DIR=$(mktemp -d)
trap 'rm -rf "$TEMP_DIR"' EXIT

curl -fsSL "$ARCHIVE_URL" -o "$TEMP_DIR/$ARCHIVE_NAME"
curl -fsSL "$CHECKSUMS_URL" -o "$TEMP_DIR/checksums.txt"

# Verify the archive against the release's checksums.txt before extracting. The checksums
# file is fetched from the same release over HTTPS, so this guards against corrupted/partial
# downloads and accidental mismatches; it is not a substitute for signature verification
# against an out-of-band key.
log "Verifying checksum..."
expected_sum=$(awk -v f="$ARCHIVE_NAME" '$2 == f {print $1}' "$TEMP_DIR/checksums.txt")
[ -n "$expected_sum" ] || abort "Could not find a checksum for $ARCHIVE_NAME in checksums.txt"
actual_sum=$(sha256sum "$TEMP_DIR/$ARCHIVE_NAME" | awk '{print $1}')
[ "$expected_sum" = "$actual_sum" ] || \
  abort "Checksum verification failed for $ARCHIVE_NAME (expected $expected_sum, got $actual_sum)"

tar xzf "$TEMP_DIR/$ARCHIVE_NAME" -C "$TEMP_DIR"

$SUDO_PREFIX mv "$TEMP_DIR/$BIN_NAME" "$INSTALL_PATH/$BIN_NAME"
$SUDO_PREFIX ln -sf "$INSTALL_PATH/$BIN_NAME" "$INSTALL_PATH/livekit-cli"

# Install completions if the corresponding system directories exist. The fish
# completion ships in the archive (no need to invoke lk to regenerate it).
if [ -d "$TEMP_DIR/autocomplete" ]; then
  [ -d "$BASH_COMPLETION_PATH" ] && \
    $SUDO_PREFIX install -m 0644 "$TEMP_DIR/autocomplete/bash_autocomplete" "$BASH_COMPLETION_PATH/livekit-cli" || true
  [ -d "$ZSH_COMPLETION_PATH" ] && \
    $SUDO_PREFIX install -m 0644 "$TEMP_DIR/autocomplete/zsh_autocomplete" "$ZSH_COMPLETION_PATH/_livekit-cli" || true
  [ -d "$FISH_COMPLETION_PATH" ] && \
    $SUDO_PREFIX install -m 0644 "$TEMP_DIR/autocomplete/fish_autocomplete" "$FISH_COMPLETION_PATH/livekit-cli.fish" || true
fi

log "\n$BIN_NAME is installed to $INSTALL_PATH\n"