#!/bin/bash

set -euo pipefail

main() {
die() { echo "Error: $*" >&2; exit 1; }
file_sha256() {
    if command -v openssl >/dev/null 2>&1; then
        openssl sha256 -r "$1" | cut -d' ' -f1
    else
        sha256sum "$1" | cut -d' ' -f1
    fi
}

arch=$(uname -m)

if [ "$(id -u)" -eq 0 ]; then
    if command -v whiptail >/dev/null 2>&1; then
        if ! whiptail --title "Warning" --yesno \
          "This script is not meant to be run as root.\n\nAre you sure you want to continue?" \
          0 0; then
            exit 1
        fi
    else
        echo "Warning: This script is not meant to be run as root."
        read -r -p "Are you sure you want to continue? [y/N] " reply
        case "$reply" in
            [Yy]|[Yy][Ee][Ss]) ;;
            *) exit 1 ;;
        esac
    fi
fi

if [ "$arch" != "riscv64" ]; then
    die "You are not on 64-bit RISC-V. felix86 only works on 64-bit RISC-V."
fi

missing=()
for cmd in curl tar unzip sudo jq patchelf whiptail sha256sum; do
    command -v "$cmd" >/dev/null 2>&1 || missing+=("$cmd")
done

if [ ${#missing[@]} -gt 0 ]; then
    die "missing required tools: ${missing[*]}
  Ubuntu/Debian: sudo apt install ${missing[*]}
  Arch:          sudo pacman -S ${missing[*]}"
fi

if [ -z "$HOME" ] || [ ! -d "$HOME" ]; then
    die "\$HOME is not set or not a valid directory."
fi

if [ -z "$USER" ]; then
    die "\$USER is not set"
fi

INSTALLATION_DIR="/opt/felix86"
FILE="$INSTALLATION_DIR/bin/felix86"
ICONS_SHA256="665a264e462b2ddd07f478b83cf34219497def4a1d8cab4cab04d56c0864d847"

IS_UPDATE=0
if [ -x "$FILE" ]; then
  IS_UPDATE=1
fi

felix86_version_gte() {
    local required="$1"
    local version
    version=$(felix86 --version 2>/dev/null | grep -oP '\d+\.\d+' | head -1)
    if [[ -z "$version" ]]; then
        return 1
    fi
    local req_major req_minor ver_major ver_minor
    IFS='.' read -r req_major req_minor <<< "$required"
    IFS='.' read -r ver_major ver_minor <<< "$version"
    if (( 10#$ver_major > 10#$req_major )) || (( 10#$ver_major == 10#$req_major && 10#$ver_minor >= 10#$req_minor )); then
        return 0
    fi
    return 1
}

check_url() {
  local url="$1"

  if ! curl --output /dev/null --silent --head --fail "$url"; then
    die "URL is invalid or unreachable: $url"
  fi
}

GITHUB_ARTIFACTS_JSON="[]"

fetch_nightly_artifacts() {
  local api="https://api.github.com/repos/OFFTKP/felix86/actions/artifacts?name=linux_artifact&per_page=100"
  local json
  json=$(curl -sfL --max-time 20 \
    -H "Accept: application/vnd.github+json" \
    -H "X-GitHub-Api-Version: 2022-11-28" "$api" 2>/dev/null \
    | jq -c '[.artifacts[] | select(.workflow_run.head_branch == "master" and .expired == false)] | sort_by(.created_at) | reverse' 2>/dev/null) || json=""
  if [[ -n "$json" && "$json" != "null" ]]; then
    GITHUB_ARTIFACTS_JSON="$json"
  fi
}

nightly_run_link() {
  echo "https://nightly.link/OFFTKP/felix86/actions/runs/$1/linux_artifact.zip"
}

select_release_url() {
  local url_list
  check_url "https://cdn.felix86.com/releases/meta.txt"
  url_list=$(curl -s https://cdn.felix86.com/releases/meta.txt)

  if [[ -z "$url_list" ]]; then
    echo "Failed to fetch the releases list or it's empty."
    return 1
  fi

  local total_lines
  total_lines=$(echo "$url_list" | wc -l)
  if (( total_lines > 5 )); then
    echo "Failed to parse https://cdn.felix86.com/releases/meta.txt"
    return 1
  fi

  local entries=()
  while IFS= read -r line && [[ ${#entries[@]} -lt 5 ]]; do
    entries+=("$line")
  done <<< "$url_list"

  if [[ ${#entries[@]} -eq 0 ]]; then
    echo "No valid entries found."
    return 1
  fi

  echo "Fetching list of artifacts from GitHub..."
  fetch_nightly_artifacts
  local nightly_count
  nightly_count=$(echo "$GITHUB_ARTIFACTS_JSON" | jq 'length')

  local menu_items=()
  for i in "${!entries[@]}"; do
    local version="${entries[$i]%% *}"
    local desc=""
    if [[ $i -eq 0 ]]; then
      desc="  (Recommended)"
    fi
    local num=$((i+1))
    menu_items+=("${num})" "felix86 $version$desc")
  done

  local latest_index=$(( ${#entries[@]} + 1 ))
  menu_items+=("${latest_index})" "Nightly version  (Unstable)")

  local choose_nightly_index=$(( ${#entries[@]} + 2 ))
  menu_items+=("${choose_nightly_index})" "Choose specific build")

  local choice
  choice=$(whiptail --title "felix86 Installer" \
    --menu "Welcome to the felix86 installer!\n\nChoose the version you'd like to install:" \
    0 0 0 \
    "${menu_items[@]}" \
    --default-item "1)" \
    3>&1 1>&2 2>&3) || exit 1
  choice="${choice%)}"

  if (( choice == latest_index )); then
    ver="latest"
    if (( nightly_count == 0 )); then
      die "Could not fetch list of artifacts from GitHub"
    fi
    local run_id
    run_id=$(echo "$GITHUB_ARTIFACTS_JSON" | jq -r '.[0].workflow_run.id')
    if [[ -z "$run_id" || "$run_id" == "null" ]]; then
      die "Failed to get latest nightly build"
    fi
    FELIX86_LINK=$(nightly_run_link "$run_id")
  elif (( choice == choose_nightly_index )); then
    if (( nightly_count == 0 )); then
      die "Could not fetch the list of nightly builds from GitHub"
    fi

    local artifact_menu=()
    local sha date
    while IFS=$'\t' read -r sha date; do
      local num=$(( ${#artifact_menu[@]} / 2 + 1 ))
      artifact_menu+=("${num})" "commit $sha  ($date)")
    done < <(echo "$GITHUB_ARTIFACTS_JSON" | jq -r '.[] | "\(.workflow_run.head_sha[0:7])\t\(.created_at | strptime("%Y-%m-%dT%H:%M:%SZ") | strftime("%Y-%m-%d %H:%M"))"')

    local artifact_menu_height=$((nightly_count > 10 ? 10 : nightly_count))
    local selection
    selection=$(whiptail --title "felix86 Installer" \
      --menu "Choose a specific nightly build:" \
      20 60 $artifact_menu_height \
      "${artifact_menu[@]}" \
      3>&1 1>&2 2>&3) || exit 1
    selection="${selection%)}"

    ver="nightly"
    local run_id
    run_id=$(echo "$GITHUB_ARTIFACTS_JSON" | jq -r ".[$((selection-1))].workflow_run.id")
    if [[ -z "$run_id" || "$run_id" == "null" ]]; then
      die "Failed to get run id for latest build"
    fi
    FELIX86_LINK=$(nightly_run_link "$run_id")
  else
    ver=${entries[$((choice-1))]}
    selected="https://github.com/OFFTKP/felix86/releases/download/$ver/felix86.$ver.zip"
    FELIX86_LINK="${selected#* }"
  fi
}

select_release_url

echo "Downloading felix86 from $FELIX86_LINK ..."
mkdir -p /tmp/felix86_artifact
curl -fL --progress-bar "$FELIX86_LINK" -o /tmp/felix86_artifact/archive.zip
unzip -oq -d /tmp/felix86_artifact /tmp/felix86_artifact/archive.zip
rm /tmp/felix86_artifact/archive.zip
echo "Moving felix86 executable to $FILE, requesting permission..."
sudo mkdir -p "$INSTALLATION_DIR"
sudo mkdir -p "$INSTALLATION_DIR/bin"
sudo mkdir -p "$INSTALLATION_DIR/lib"
sudo mkdir -p "$INSTALLATION_DIR/lib/x86_64-linux-gnu"
sudo mkdir -p "$INSTALLATION_DIR/lib/riscv64-linux-gnu"
sudo mkdir -p "$INSTALLATION_DIR/licenses"

sudo mv /tmp/felix86_artifact/felix86 $FILE
if [ -f "/tmp/felix86_artifact/felix86.png" ]; then
  sudo mv "/tmp/felix86_artifact/felix86.png" "$INSTALLATION_DIR/felix86.png"
fi
if ! command -v xdg-icon-resource >/dev/null 2>&1; then
  echo "xdg-icon-resource not found, skipping icon installation" 
elif [ ! -f "$HOME/.local/share/icons/hicolor/128x128/apps/offtkp-felix86.png" ]; then
  echo "Installing icons..."
  curl -fsSL -o /tmp/felix86_icons.zip https://cdn.felix86.com/images/icons.zip
  ICONS_ACTUAL_SHA256=$(file_sha256 "/tmp/felix86_icons.zip")
  if [[ "$ICONS_ACTUAL_SHA256" != "$ICONS_SHA256" ]]; then
    rm -f /tmp/felix86_icons.zip
    echo "Checksum mismatch for icons.zip (expected $ICONS_SHA256, got $ICONS_ACTUAL_SHA256), skipping icon installation"
  else
    TMP_DIR="$(mktemp -d /tmp/felix86_icons.XXXXXX)"
    cleanup() {
      rm -rf "$TMP_DIR"
    }
    trap cleanup EXIT
    unzip -oq /tmp/felix86_icons.zip -d "$TMP_DIR"
    rm /tmp/felix86_icons.zip
    for size in 16 24 32 48 96 128; do
      xdg-icon-resource install --context apps --size "$size" \
        "$TMP_DIR/icons/${size}x${size}/felix86.png" offtkp-felix86
    done
  fi
fi
sudo mv /tmp/felix86_artifact/lib/x86_64-linux-gnu/* "$INSTALLATION_DIR/lib/x86_64-linux-gnu/"

FELIX86_GLIBC_VERSION_FILE="$INSTALLATION_DIR/lib/riscv64-linux-gnu/.felix86-glibc-version"
INSTALLED_GLIBC_VERSION=""
if [ -f "$FELIX86_GLIBC_VERSION_FILE" ]; then
  INSTALLED_GLIBC_VERSION=$(cat "$FELIX86_GLIBC_VERSION_FILE")
fi

FELIX86_GLIBC_VERSION=$(curl -sfL --max-time 20 \
  -H "Accept: application/vnd.github+json" \
  -H "X-GitHub-Api-Version: 2022-11-28" \
  "https://api.github.com/repos/felix86-emu/glibc/releases/latest" 2>/dev/null \
  | jq -r '.tag_name // empty' 2>/dev/null) || FELIX86_GLIBC_VERSION=""

if [ -z "$FELIX86_GLIBC_VERSION" ]; then
    echo "Could not fetch latest glibc release version, skipping custom glibc installation"
elif [ ! -f "$INSTALLATION_DIR/lib/riscv64-linux-gnu/libc.so.6" ] || [ "$INSTALLED_GLIBC_VERSION" != "$FELIX86_GLIBC_VERSION" ]; then
  echo "Downloading custom glibc fork ($FELIX86_GLIBC_VERSION)..."
  mkdir -p /tmp/felix86_artifact/glibc
  FELIX86_GLIBC_LINK="https://github.com/felix86-emu/glibc/releases/download/$FELIX86_GLIBC_VERSION/glibc-felix86.zip"
  curl -fSL --progress-bar "$FELIX86_GLIBC_LINK" -o /tmp/felix86_artifact/glibc/glibc.zip
  unzip -oq -d /tmp/felix86_artifact/glibc /tmp/felix86_artifact/glibc/glibc.zip
  rm /tmp/felix86_artifact/glibc/glibc.zip
  sudo mv -f /tmp/felix86_artifact/glibc/lib/riscv64-linux-gnu/* "$INSTALLATION_DIR/lib/riscv64-linux-gnu/"
  sudo mv -f /tmp/felix86_artifact/glibc/licenses/COPYING.LESSERv2 "$INSTALLATION_DIR/licenses/glibc_LICENSE"
  echo "$FELIX86_GLIBC_VERSION" | sudo tee "$FELIX86_GLIBC_VERSION_FILE" >/dev/null
  rmdir /tmp/felix86_artifact/glibc/lib/riscv64-linux-gnu
  rmdir /tmp/felix86_artifact/glibc/lib
  rmdir /tmp/felix86_artifact/glibc/licenses
  rmdir /tmp/felix86_artifact/glibc
fi

# Old script would install in /usr/bin/felix86, check if its such a symlink and if it is remove it
if [ -e "/usr/bin/felix86" ] || [ -L "/usr/bin/felix86" ]; then
    if [ -L "/usr/bin/felix86" ]; then
        if [ "$(readlink -f "/usr/bin/felix86")" = "$(readlink -f "$INSTALLATION_DIR/felix86")" ]; then
            echo "/usr/bin/felix86 is a symlink to $INSTALLATION_DIR/felix86, leftover from older installation script, removing it"
            sudo rm "/usr/bin/felix86"
        fi
    fi
fi
# This is now moved to $INSTALLATION_DIR/bin, remove old executable to prevent confusion
if [ -f "$INSTALLATION_DIR/felix86" ] && [ -x "$INSTALLATION_DIR/felix86" ]; then
    echo "$INSTALLATION_DIR/felix86 exists, leftover from older installation script, removing it"
    sudo rm "$INSTALLATION_DIR/felix86"
fi
sudo ln -sf "$FILE" /usr/local/bin/felix86
FELIX86_LD="$INSTALLATION_DIR/lib/riscv64-linux-gnu/ld-linux-riscv64-lp64d.so.1"
if [ -f "$FELIX86_LD" ] && [ -f "$INSTALLATION_DIR/lib/riscv64-linux-gnu/libc.so.6" ]; then
  sudo patchelf --set-interpreter "$FELIX86_LD" \
           --add-rpath "$INSTALLATION_DIR/lib/riscv64-linux-gnu" \
           "$FILE"
else
  echo "Custom glibc not found in $INSTALLATION_DIR/lib/riscv64-linux-gnu, using the system glibc"
fi
sudo chown 0:0 "$FILE"
sudo chmod +x "$FILE"
sudo chown -R 0:0 "$INSTALLATION_DIR/lib"
echo "Successfully installed felix86 at $FILE and libraries at $INSTALLATION_DIR/lib"
if felix86_version_gte "26.08"; then
  sudo felix86 --set-config general.thunks_path=$INSTALLATION_DIR/lib
else
  felix86 --set-thunks $INSTALLATION_DIR/lib
fi

rmdir /tmp/felix86_artifact/lib/x86_64-linux-gnu
rmdir /tmp/felix86_artifact/lib
rmdir /tmp/felix86_artifact

if felix86_version_gte "26.08"; then
  current_rootfs=$(felix86 --get-config general.rootfs_path)
else
  current_rootfs=$(felix86 -g)
fi
INSTALL_ROOTFS=1
if [[ -n "$current_rootfs" && -d "$current_rootfs" ]]; then
  INSTALL_ROOTFS=0
  echo "Looks like you already have a rootfs at $current_rootfs, I will not install a new rootfs"
  echo "If you want to install a new rootfs use the rootfs installer script:"
  echo "    curl -fsSL https://install.felix86.com/rootfs.sh"
fi

if [[ "$INSTALL_ROOTFS" == "1" ]]; then
  bash <(curl -fsSL https://install.felix86.com/rootfs.sh)
fi

if felix86_version_gte "26.08"; then
  NEW_ROOTFS=$(felix86 --get-config general.rootfs_path)
else
  NEW_ROOTFS=$(felix86 -g)
fi

# Finally register felix86 in binfmt_misc
sudo --preserve-env=HOME felix86 --binfmt-misc

# Let's try to run a test program
set +e
FELIX86_QUIET=1 felix86 "$NEW_ROOTFS/bin/bash" -c "exit 42"
exit_code=$?

# If everything went fine, felix86 should return 42
if [ "$exit_code" -ne 42 ]; then
    echo "Running again with logging enabled:"
    felix86 "$NEW_ROOTFS/bin/bash" -c "exit 42"
    die "felix86 failed to run a simple program -- may not have installed correctly?"
fi

if [ "$IS_UPDATE" -eq 1 ]; then
  echo "felix86 successfully updated."
else
  whiptail --title "felix86 is now installed!" --msgbox \
"To enter an emulated bash, use:

  felix86 --shell

    OR

  felix86 /path/to/rootfs/bin/bash

Alternatively, run programs directly:

  /path/to/rootfs/MyGame.AppImage" \
20 50
fi

if ! felix86 -d; then
  echo "Failed binfmt_misc installation check"
  echo "felix86 is currently not used as the default emulator for x86 applications"
  echo "If you have other x86 emulators registered then you will need to unregister them"
  echo "Example of unregistering an emulator: sudo sh -c \"echo -1 > /proc/sys/fs/binfmt_misc/qemu-x86_64\""
  echo "To make this change permanent, make sure to remove the respective file from one of these directories:"
  echo "  /etc/binfmt.d"
  echo "  /run/binfmt.d"
  echo "  /usr/local/lib/binfmt.d"
  echo "  /usr/lib/binfmt.d"
  echo "After you're done, to register felix86, run: sudo $FILE -b"
  echo "If you don't register to binfmt_misc, some apps like sudo (needed by AppImages) will not work"
fi

echo "Refer to the usage guide for more info: https://felix86.com/docs/users/usage-guide/"
}

main "$@"