#!/usr/bin/env -S uv run --script
# /// script
# requires-python = ">=3.12"
# dependencies = ["pyyaml>=6.0", "rich>=13.0.0"]
# ///
#MISE description="Validate all wiki-links point to existing doc titles"
"""Validate that all wiki-links in documentation point to existing titles.

This script scans all markdown files in the docs/ directory (excluding
changelog.d/ and zk/), extracts wiki-links, and verifies each link target
exists as a frontmatter title in the documentation.

Wiki-link formats supported:
- [[Title]] - links to a doc with frontmatter title "Title"
- [[Title|Display Text]] - links to "Title", displays "Display Text"

Usage: mise run doc-links
"""

import re
import sys
from collections import defaultdict
from pathlib import Path

import yaml
from rich.console import Console
from rich.markup import escape
from rich.table import Table

DOCS_DIR = Path(__file__).parent.parent / "docs"

# Regex to match wiki-links: [[Target]] or [[Target|Display]]
WIKILINK_PATTERN = re.compile(r"\[\[([^\]|]+)(?:\|[^\]]+)?\]\]")

# Regex to match inline code (backticks)
INLINE_CODE_PATTERN = re.compile(r"`[^`]+`")


def extract_frontmatter(file_path: Path) -> dict | None:
    """Extract YAML frontmatter from a markdown file."""
    content = file_path.read_text()
    if not content.startswith("---"):
        return None

    end_idx = content.find("---", 3)
    if end_idx == -1:
        return None

    frontmatter_text = content[3:end_idx].strip()
    try:
        return yaml.safe_load(frontmatter_text) or {}
    except yaml.YAMLError:
        return None


def extract_wikilinks(file_path: Path) -> list[tuple[str, int]]:
    """Extract all wiki-link targets from a markdown file with line numbers.

    Ignores wiki-links inside inline code (backticks) as these are examples.
    """
    content = file_path.read_text()
    links = []

    for line_num, line in enumerate(content.splitlines(), start=1):
        # Remove inline code before searching for wiki-links
        line_without_code = INLINE_CODE_PATTERN.sub("", line)
        for match in WIKILINK_PATTERN.finditer(line_without_code):
            target = match.group(1).strip()
            links.append((target, line_num))

    return links


def main() -> int:
    console = Console()

    # Collect all valid titles from frontmatter
    valid_titles: set[str] = set()

    # Scan all markdown files for titles (excluding zk/ and changelog.d/)
    for md_file in DOCS_DIR.rglob("*.md"):
        if "changelog.d" in md_file.parts or "zk" in md_file.parts:
            continue

        frontmatter = extract_frontmatter(md_file)
        if frontmatter and frontmatter.get("title"):
            valid_titles.add(frontmatter["title"])

    # Collect all broken links
    # Key: (file_path, line_num), Value: target
    broken_links: list[tuple[str, int, str]] = []

    # Scan all markdown files for wiki-links (excluding zk/ and changelog.d/)
    for md_file in sorted(DOCS_DIR.rglob("*.md")):
        if "changelog.d" in md_file.parts or "zk" in md_file.parts:
            continue

        rel_path = str(md_file.relative_to(DOCS_DIR))
        links = extract_wikilinks(md_file)

        for target, line_num in links:
            if target not in valid_titles:
                broken_links.append((rel_path, line_num, target))

    # Print results
    console.print("[bold]Wiki-Link Validation[/bold]")
    console.print()
    console.print(f"Found {len(valid_titles)} valid titles in documentation.")
    console.print()

    if broken_links:
        console.print("[bold red]Broken Wiki-Links Found[/bold red]")
        table = Table(show_header=True, header_style="bold")
        table.add_column("File")
        table.add_column("Line", justify="right")
        table.add_column("Target")

        for file_path, line_num, target in broken_links:
            table.add_row(file_path, str(line_num), escape(f"[[{target}]]"))

        console.print(table)
        console.print()
        console.print(f"[bold red]{len(broken_links)} broken link(s) found.[/bold red]")
        console.print()
        console.print("Each wiki-link target must match a frontmatter title in docs/.")
        return 1

    console.print("[bold green]All wiki-links are valid![/bold green]")
    return 0


if __name__ == "__main__":
    sys.exit(main())