# This script is meant to be sourced.
# It's not for directly running.

# See https://github.com/end-4/dots-hyprland/issues/2137
#
# Stage 1 todos:
# TODO: Properly handle hyprland config, ~/.config/hypr/hyprland.conf should be overwritten only when firstrun
# TODO: add --exp-files-path <path>   Use <path> instead of the default yaml config
# TODO: add --exp-files-regen         Force copy the default config to ${EXP_FILE_PATH} (auto do this when not existed)
# TODO: Implement versioning, i.e. when user-defined yaml config file has version number mismatch with the default one, produce error. If only minor version number is not the same, the error can be ommitted via --exp-file-no-strict .
# TODO: add --exp-files-no-strict     Ignore error when minor version number is not the same
# TODO: When --via-nix is specified, use dots-extra/vianix/hypridle.conf instead
#
# Stage 2 todos:
# TODO: Implement bool key symlink (both read-write and read-only), when the value of `symlink` is true, then instead using `rsync` or `cp`, use `ln`.
# TODO: add --exp-file-reset-symlink  Try to remove all symlink in .config and .local, which point to the local repo
# TODO: Update help and doc about `--exp-files` and the yaml config, including the possible values of mode.
#
# Stage 3 todos:
# TODO: Implement user-define yaml with merging (override) ability for user who only wants little customization and is satisfied with most of the defaults. User can use `./install-files.yaml` as custom config. When `./install-files.yaml` exists and have correct major version number, merge it together with `sdata/step/3.install-files.yaml` to generate a `cache/install-files.final.yaml` to determine how to copy files. About how to merge two yaml files, I know some software such as rime input method and docker supports a override yaml config, which we may reference from. See also https://github.com/mikefarah/yq/discussions/1437
# TODO: Implement variants like keybindings, terminals, etc under user_preferences.

# Configuration file
CONFIG_FILE="sdata/subcmd-install/3.files-exp.yaml"

# =============================================================================
wizard_update_preferences() {
  echo -e "${STY_CYAN}=== Dotfiles Customization ===${STY_RESET}"

    # Get current preferences
    current_shell=$(yq '.user_preferences.shell // "fish"' "$CONFIG_FILE")
    current_terminal=$(yq '.user_preferences.terminal // "kitty"' "$CONFIG_FILE")
    current_keybindings=$(yq '.user_preferences.keybindings // "default"' "$CONFIG_FILE")

    echo "Current preferences:"
    echo "  Shell: $current_shell"
    echo "  Terminal: $current_terminal"
    echo "  Keybindings: $current_keybindings"
    echo

    # Shell selection
    echo "Which shell do you prefer?"
    echo "1) fish (default)"
    echo "2) zsh"
    read -p "Enter choice [1-2]: " shell_choice

    case "$shell_choice" in
      1|"") shell="fish" ;;
      2) shell="zsh" ;;
      *) echo "Invalid choice, using fish"; shell="fish" ;;
    esac

    # Terminal selection
    echo
    echo "Which terminal do you prefer?"
    echo "1) kitty (default)"
    echo "2) foot"
    read -p "Enter choice [1-2]: " terminal_choice

    case "$terminal_choice" in
      1|"") terminal="kitty" ;;
      2) terminal="foot" ;;
      *) echo "Invalid choice, using kitty"; terminal="kitty" ;;
    esac

    # Keybindings selection
    echo
    echo "Which keybinding style do you prefer?"
    echo "1) default (arrow keys)"
    echo "2) vim (H/J/K/L)"
    read -p "Enter choice [1-2]: " keybind_choice

    case "$keybind_choice" in
      1|"") keybindings="default" ;;
      2) keybindings="vim" ;;
      *) echo "Invalid choice, using default"; keybindings="default" ;;
    esac

    # Update YAML in-place
    yq -i ".user_preferences.shell = \"$shell\"" "$CONFIG_FILE"
    yq -i ".user_preferences.terminal = \"$terminal\"" "$CONFIG_FILE"
    yq -i ".user_preferences.keybindings = \"$keybindings\"" "$CONFIG_FILE"

    echo
    echo "Preferences updated!"
  }

# Get user preference
get_pref() {
  yq -r ".user_preferences.$1" "$CONFIG_FILE"
}

# Check if pattern should be processed based on user preferences
should_process_pattern() {
  local pattern="$1"
  local condition=$(echo "$pattern" | yq '.condition // "true"')

    # If no condition or condition is "true", always process
    if [[ "$condition" == "true" ]]; then
      return 0
    fi

    # Extract the preference type and value from condition
    local type=$(echo "$condition" | yq '.type')
    local value=$(echo "$condition" | yq '.value')

    [[ "$(get_pref "$type")" == "$value" ]]

  }

# Compare hashes of files/directories, return true if they are the same, false otherwise
files_are_same() {
  local path1="$1"
  local path2="$2"

    # Check if paths exist
    if [[ ! -e "$path1" || ! -e "$path2" ]]; then
      return 1
    fi

    # For directories, use find + md5sum to compare recursively
    # For files, use md5sum directly
    if [[ -d "$path1" && -d "$path2" ]]; then
      # Compare directory contents using find and md5sum
      local hash1=$(find "$path1" -type f -exec md5sum {} \; | sort -k 2 | md5sum | awk '{print $1}')
      local hash2=$(find "$path2" -type f -exec md5sum {} \; | sort -k 2 | md5sum | awk '{print $1}')
      [[ "$hash1" == "$hash2" ]]
    elif [[ -f "$path1" && -f "$path2" ]]; then
      # Compare file hashes
      local hash1=$(md5sum "$path1" | awk '{print $1}')
      local hash2=$(md5sum "$path2" | awk '{print $1}')
      [[ "$hash1" == "$hash2" ]]
    else
      # One is a file, one is a directory - different types
      return 1
    fi
  }

# Find next backup number
get_next_backup_number() {
  local base_path="$1"
  local counter=1

  while [[ -e "${base_path}.old.${counter}" ]]; do
    ((counter++))
  done

  echo $counter
}

# =============================================================================
# MAIN EXECUTION
# =============================================================================

# Run user preference wizard
case $ask in
  false) sleep 0 ;;
  *) wizard_update_preferences ;;
esac

# Read patterns from YAML file
readarray patterns < <(yq -o=j -I=0 '.patterns[]' "$CONFIG_FILE")

# Process each pattern
for pattern in "${patterns[@]}"; do
  from=$(echo "$pattern" | yq '.from' - | envsubst)
  to=$(echo "$pattern" | yq '.to' - | envsubst)
  mode=$(echo "$pattern" | yq '.mode' - | envsubst)
  condition=$(echo "$pattern" | yq '.condition // "true"')

  # Handle fontconfig fontset override
  # If FONTSET_DIR_NAME is set and this is the fontconfig pattern, use the fontset instead
  if [[ "$from" == "dots/.config/fontconfig" ]] && [[ -n "${FONTSET_DIR_NAME:-}" ]]; then
    from="dots-extra/fontsets/${FONTSET_DIR_NAME}"
    echo "Using fontset \"${FONTSET_DIR_NAME}\" for fontconfig"
  fi

  # Check if pattern should be processed
  if ! should_process_pattern "$pattern"; then
    # Format condition message nicely
    if [[ "$condition" != "true" ]]; then
      cond_type=$(echo "$condition" | yq -r '.type // ""')
      cond_value=$(echo "$condition" | yq -r '.value // ""')
      if [[ -n "$cond_type" && -n "$cond_value" ]]; then
        echo "Skipping $from -> $to (condition not met: $cond_type == '$cond_value')"
      else
        echo "Skipping $from -> $to (condition not met)"
      fi
    else
      echo "Skipping $from -> $to (condition not met)"
    fi
    continue
  fi

  echo "Processing: $from -> $to (mode: $mode)"

  # Build exclude arguments for rsync
  excludes=()
  if echo "$pattern" | yq -e '.excludes' >/dev/null 2>&1; then
    while IFS= read -r exclude; do
      excludes+=(--exclude "$exclude")
    done < <(echo "$pattern" | yq -r '.excludes[]')
  fi

  # Check if source exists
  if [[ ! -e "$from" ]]; then
    echo "Warning: Source does not exist: $from (skipping)"
    continue
  fi

  # Ensure destination directory exists for files
  if [[ -f "$from" ]]; then
    v mkdir -p "$(dirname "$to")"
  fi

  # Execute based on mode
  case $mode in
    "sync")
      if [[ -d "$from" ]]; then
        warning_rsync_delete
        v rsync -av --delete "${excludes[@]}" "$from/" "$to/"
      else
        warning_rsync_normal
        # For files, don't use trailing slash and don't use --delete
        v rsync -av "${excludes[@]}" "$from" "$to"
      fi
      ;;
    "soft")
      warning_rsync_normal
      if [[ -d "$from" ]]; then
        v rsync -av "${excludes[@]}" "$from/" "$to/"
      else
        # For files, don't use trailing slash
        v rsync -av "${excludes[@]}" "$from" "$to"
      fi
      ;;
    "hard")
      v cp -r "$from" "$to"
      ;;
    "hard-backup")
      if [[ -e "$to" ]]; then
        if files_are_same "$from" "$to"; then
          echo "Files are identical, skipping backup"
        else
          backup_number=$(get_next_backup_number "$to")
          v mv "$to" "$to.old.$backup_number"
          v cp -r "$from" "$to"
        fi
      else
        v cp -r "$from" "$to"
      fi
      ;;
    "soft-backup")
      if [[ -e "$to" ]]; then
        if files_are_same "$from" "$to"; then
          echo "Files are identical, skipping backup"
        else
          v cp -r "$from" "$to.new"
        fi
      else
        v cp -r "$from" "$to"
      fi
      ;;
    "skip")
      echo "Skipping $from"
      ;;
    "skip-if-exists")
      if [[ -e "$to" ]]; then
        echo "Skipping $from (destination exists)"
      else
        v cp -r "$from" "$to"
      fi
      ;;
    *)
      echo "Unknown mode: $mode"
      ;;
  esac
done