#!/usr/bin/env bash
set -euo pipefail

MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.mosaic}"

backup_stamp="$(date +%Y%m%d%H%M%S)"

link_file() {
  local src="$1"
  local dst="$2"

  mkdir -p "$(dirname "$dst")"

  if [[ -L "$dst" ]]; then
    local cur
    cur="$(readlink -f "$dst" 2>/dev/null || true)"
    local want
    want="$(readlink -f "$src" 2>/dev/null || true)"
    if [[ -n "$cur" && -n "$want" && "$cur" == "$want" ]]; then
      return
    fi
    rm -f "$dst"
  elif [[ -e "$dst" ]]; then
    mv "$dst" "${dst}.mosaic-bak-${backup_stamp}"
  fi

  ln -s "$src" "$dst"
}

link_tree_files() {
  local src_root="$1"
  local dst_root="$2"

  [[ -d "$src_root" ]] || return

  while IFS= read -r -d '' src; do
    local rel
    rel="${src#$src_root/}"
    local dst="$dst_root/$rel"
    link_file "$src" "$dst"
  done < <(find "$src_root" -type f -print0)
}

# Claude compatibility layer: keep existing ~/.claude workflows functional,
# but source canonical rails from ~/.mosaic.
link_tree_files "$MOSAIC_HOME/guides" "$HOME/.claude/agent-guides"
link_tree_files "$MOSAIC_HOME/rails/git" "$HOME/.claude/scripts/git"
link_tree_files "$MOSAIC_HOME/rails/codex" "$HOME/.claude/scripts/codex"
link_tree_files "$MOSAIC_HOME/rails/bootstrap" "$HOME/.claude/scripts/bootstrap"
link_tree_files "$MOSAIC_HOME/templates/agent" "$HOME/.claude/templates"

for qa_script in \
  debug-hook.sh \
  qa-hook-handler.sh \
  qa-hook-stdin.sh \
  qa-hook-wrapper.sh \
  qa-queue-monitor.sh \
  remediation-hook-handler.sh; do
  src="$MOSAIC_HOME/rails/qa/$qa_script"
  [[ -f "$src" ]] || continue
  link_file "$src" "$HOME/.claude/scripts/$qa_script"
done

echo "[mosaic-link] Runtime compatibility assets linked"
echo "[mosaic-link] Canonical source: $MOSAIC_HOME"