<script setup>
import { useTreeState } from '~/composables/useTreeState'

defineProps({ nodes: Array, depth: { type: Number, default: 0 } })

const router = useRouter()
const { collapsed } = useTreeState()   // ← shared state, not local ref

function getTitle(node) {
  if (node.title === 'index') return 'Index'
  return node.title || node._path?.split('/').pop() || 'Home'
}

function navigate(path) {
  if (!path) return
  router.push(path)
}

function toggle(key) {
  collapsed.value[key] = !collapsed.value[key]
}
</script>

<template>
  <ul :style="{ paddingLeft: depth ? '1rem' : '0' }">
    <li v-for="node in nodes" :key="node.path ?? node.title">

      <template v-if="!node.children?.length">
        <a v-if="node.path" :href="node.path" @click.prevent="navigate(node.path)">
          {{ getTitle(node) }}
        </a>
        <span v-else>{{ getTitle(node) }}</span>
      </template>

      <template v-else>
        <button class="folder-toggle" @click="toggle(node.path ?? node.title)">
          <span class="chevron" :class="{ open: !collapsed[node.path ?? node.title] }">›</span>
          {{ getTitle(node) }}
        </button>
        <TreeNode
          v-if="!collapsed[node.path ?? node.title]"
          :nodes="node.children"
          :depth="depth + 1"
        />
      </template>

    </li>
  </ul>
</template>

<style lang="scss" scoped>
ul {
  list-style: none;
  padding-left: 0;
}

li {
  margin-bottom: 0;
}

a {
  color: var(--text-link);
}

.folder-toggle {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  background: none;
  border: none;
  padding: 0;
  cursor: pointer;
  color: inherit;
  font: inherit;
  width: 100%;
  text-align: left;

  &:hover {
    color: var(--text-link);
  }
}

.chevron {
  display: inline-block;
  font-style: normal;
  transition: transform 0.15s ease;
  transform: rotate(0deg);
  line-height: 1;

  &.open {
    transform: rotate(90deg);
  }
}
</style>