"""
generate_sidebar_tree.py

Generates sidebar-tree.json from the org-roam directory.

Output shape:
{
  "mocs": [
    { "title": "Brain MOC", "url": "/20241210233721-brain_moc.html", "pinned": true },
    ...
  ],
  "tree": [
    {
      "label": "Articles",
      "children": [],
      "files": [{ "title": "...", "url": "/Articles/....html" }]
    },
    ...
  ],
  "exclude": [".packages"]
}
"""

import json
import re
from pathlib import Path

EXCLUDE_DIRS = {".packages", ".git", ".cursor"}
EXCLUDE_FILES = {"index.org", "all-files.org"}
MOC_PINNED_TITLES = {"brain moc"}
PINNED_URL_SUFFIX = "brain_moc.html"


def should_skip(file_path: Path, org_dir: Path) -> bool:
    """Return True if this org file should be excluded from the sidebar."""
    try:
        relative = file_path.relative_to(org_dir)
    except ValueError:
        return True

    if file_path.name in EXCLUDE_FILES:
        return True

    for part in relative.parts[:-1]:
        if part in EXCLUDE_DIRS or part.startswith("."):
            return True

    return False


def get_org_metadata(file_path: Path) -> dict:
    """Extract title, filetags, and id from an Org file."""
    title_pattern = re.compile(r"^#\+title:\s*(.+)", re.IGNORECASE | re.MULTILINE)
    tags_pattern = re.compile(r"^#\+filetags:\s*(.+)", re.IGNORECASE | re.MULTILINE)
    id_pattern = re.compile(r"^:ID:\s*(.+)", re.MULTILINE)

    try:
        content = file_path.read_text(encoding="utf-8", errors="ignore")
    except OSError:
        return {}

    title_match = title_pattern.search(content)
    tags_match = tags_pattern.search(content)
    id_match = id_pattern.search(content)

    tags_raw = tags_match.group(1).strip() if tags_match else ""
    tags = {t.strip(":").lower() for t in re.findall(r":[^:\s]+:", tags_raw)}

    return {
        "title": title_match.group(1).strip() if title_match else "Untitled",
        "tags": tags,
        "id": id_match.group(1).strip() if id_match else None,
    }


def is_moc(meta: dict) -> bool:
    return "moc" in meta.get("tags", set())


def build_mocs(org_dir: Path) -> list[dict]:
    """Collect MOC notes tagged with :moc:."""
    mocs = []

    for file_path in org_dir.rglob("*.org"):
        if re.search(r"/\.#[^/]+\.org$", str(file_path)):
            continue
        if should_skip(file_path, org_dir):
            continue

        meta = get_org_metadata(file_path)
        if not meta or not is_moc(meta):
            continue

        try:
            relative = file_path.relative_to(org_dir).with_suffix("")
        except ValueError:
            continue

        url = f"/{relative}.html"
        title = meta["title"]
        pinned = (
            title.strip().lower() in MOC_PINNED_TITLES
            or url.endswith(PINNED_URL_SUFFIX)
        )
        mocs.append({"title": title, "url": url, "pinned": pinned})

    mocs.sort(key=lambda m: (not m["pinned"], m["title"].lower()))
    return mocs


def build_tree(org_dir: Path) -> list:
    """Build nested folder tree based on filesystem structure."""

    def insert_node(nodes, parts, entry):
        if not parts:
            return

        label = parts[0]
        node = next((n for n in nodes if n["label"] == label), None)
        if not node:
            node = {"label": label, "children": [], "files": []}
            nodes.append(node)

        if len(parts) == 1:
            node["files"].append(entry)
        else:
            insert_node(node["children"], parts[1:], entry)

    tree = []
    root_files = []

    for file_path in org_dir.rglob("*.org"):
        if re.search(r"/\.#[^/]+\.org$", str(file_path)):
            continue
        if should_skip(file_path, org_dir):
            continue

        meta = get_org_metadata(file_path)
        if not meta:
            continue

        try:
            relative = file_path.relative_to(org_dir)
        except ValueError:
            continue

        entry = {
            "title": meta["title"],
            "url": f"/{relative.with_suffix('')}.html",
        }

        folder_parts = relative.parts[:-1]
        if not folder_parts:
            root_files.append(entry)
        else:
            insert_node(tree, list(folder_parts), entry)

    if root_files:
        root_files.sort(key=lambda f: f["title"].lower())
        tree.insert(0, {"label": "Garden", "children": [], "files": root_files})

    def sort_tree(nodes):
        nodes.sort(key=lambda n: n["label"].lower())
        for node in nodes:
            node["files"].sort(key=lambda f: f["title"].lower())
            sort_tree(node["children"])

    sort_tree(tree)
    return tree


def count_nodes(nodes):
    total_files = 0
    total_folders = 0

    if not nodes:
        return 0, 0

    for node in nodes:
        total_folders += 1
        total_files += len(node.get("files", []))
        child_files, child_folders = count_nodes(node.get("children", []))
        total_files += child_files
        total_folders += child_folders

    return total_files, total_folders


def generate_sidebar_tree(org_dir: Path, out_file: Path) -> None:
    """Generate sidebar-tree.json with MOC hubs and folder tree."""
    print(" Generating sidebar-tree.json...")

    org_dir = org_dir.expanduser().resolve()
    out_file = out_file.expanduser()

    output = {
        "mocs": build_mocs(org_dir),
        "tree": build_tree(org_dir),
        "exclude": sorted(EXCLUDE_DIRS),
    }

    out_file.parent.mkdir(parents=True, exist_ok=True)
    with open(out_file, "w", encoding="utf-8") as f:
        json.dump(output, f, ensure_ascii=False, indent=2)

    files_count, folder_count = count_nodes(output["tree"])
    print(
        f" sidebar-tree.json generated "
        f"({len(output['mocs'])} mocs, {folder_count} folders, {files_count} files)"
    )
    print(f"   → {out_file}")


def main():
    base_dir = Path.home() / "master-folder" / "org_files" / "org_roam"
    sidebar_tree = base_dir / "output" / "assets" / "sidebar-tree.json"
    generate_sidebar_tree(base_dir, sidebar_tree)


if __name__ == "__main__":
    main()