#!/usr/bin/env python3
"""Regenerate _ideas-index.md as a two-level outline from idea frontmatter.

Hierarchy comes from each idea's `parent:` field (empty = root/main idea).
Roots are ranked by total paper engagement (own + descendants), so the most
contested conversations float to the top. Paper counts per idea in brackets.

    python3 _scripts/make_ideas_index.py
"""
import glob
import os
import re
from collections import defaultdict

VAULT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


def fm_field(text: str, name: str) -> str:
    m = re.search(rf'^{name}: (.*)$', text.split("---")[1], flags=re.M)
    return m.group(1).strip().strip('"') if m else ""


def main() -> None:
    ideas, parent, statement = set(), {}, {}
    for path in glob.glob(os.path.join(VAULT, "ideas", "*.md")):
        slug = os.path.splitext(os.path.basename(path))[0]
        text = open(path, encoding="utf-8").read()
        ideas.add(slug)
        statement[slug] = fm_field(text, "statement")
        p = re.sub(r"[\[\]]", "", fm_field(text, "parent"))
        parent[slug] = p if p in (None, "") else p

    # paper engagement counts
    count = defaultdict(int)
    for path in glob.glob(os.path.join(VAULT, "papers", "*.md")) + glob.glob(os.path.join(VAULT, "influences", "*.md")):
        seen = set()
        for m in re.finditer(r'^(first-mention|argues-for|argues-against|nuances|tests)::\s*\[\[(.+?)\]\]',
                             open(path, encoding="utf-8").read(), flags=re.M):
            if m.group(2) in ideas:
                seen.add(m.group(2))
        for s in seen:
            count[s] += 1

    children = defaultdict(list)
    roots = []
    for s in sorted(ideas):
        p = parent.get(s) or ""
        if p and p in ideas:
            children[p].append(s)
        else:
            roots.append(s)
            if p and p not in ideas:
                print(f"WARN: parent of {s} does not resolve: {p}")

    def subtree_count(s):
        return count[s] + sum(subtree_count(c) for c in children[s])

    lines = ["---", "tags: [meta]", "---", "", "# Ideas index", "",
             "Generated by `_scripts/make_ideas_index.py` from idea frontmatter —",
             "set an idea's `parent:` field to place it; empty parent = main idea.",
             "Roots ranked by total paper engagement (own + sub-ideas); `[n]` = papers",
             "engaging that idea directly. Skills check this outline before creating",
             "a new idea — a candidate that restates any line below links instead.", ""]

    def emit(s, depth):
        short = statement[s]
        if len(short) > 1 and not short[1].isupper():
            short = short[0].lower() + short[1:]
        short = short.split(";")[0]
        lines.append(f"{'  ' * depth}- [[{s}]] `[{count[s]}]` — {short}")
        for c in sorted(children[s], key=lambda x: (-subtree_count(x), x)):
            emit(c, depth + 1)

    for r in sorted(roots, key=lambda x: (-subtree_count(x), x)):
        emit(r, 0)

    open(os.path.join(VAULT, "_ideas-index.md"), "w", encoding="utf-8").write("\n".join(lines) + "\n")
    print(f"wrote outline: {len(roots)} main ideas, {len(ideas) - len(roots)} sub-ideas")

    # maintain a Sub-ideas section on parent notes (marker-delimited; added/removed as hierarchy changes)
    START, END = "<!-- SUBIDEAS:START (generated by make_ideas_index.py) -->", "<!-- SUBIDEAS:END -->"
    BLOCK = START + """
## Sub-ideas

```dataview
TABLE WITHOUT ID file.link AS "Sub-idea", status AS Status
FROM "ideas"
WHERE contains(string(parent), this.file.name)
SORT file.name ASC
```
""" + END
    touched = 0
    for s in ideas:
        path = os.path.join(VAULT, "ideas", f"{s}.md")
        text = open(path, encoding="utf-8").read()
        has_block = START in text
        if children[s] and not has_block:
            if "\n## Notes" in text:
                text = text.replace("\n## Notes", "\n" + BLOCK + "\n## Notes", 1)
            else:
                text = text.rstrip("\n") + "\n\n" + BLOCK + "\n"
            open(path, "w", encoding="utf-8").write(text); touched += 1
        elif not children[s] and has_block:
            text = re.sub(re.escape(START) + r".*?" + re.escape(END) + r"\n?", "", text, flags=re.S)
            open(path, "w", encoding="utf-8").write(text); touched += 1
    print(f"sub-ideas sections maintained on {touched} notes")


if __name__ == "__main__":
    main()