#!/usr/bin/env python3
"""Check documentation coverage for CLI commands and major modules.

Parses Click commands from the CLI source code and checks if each command
has corresponding documentation in the wiki/docs.  Reports missing
documentation as warnings and exits with non-zero if coverage is below 100%.

Usage:
  python3 scripts/ci/doc_coverage.py [--docs-dir docs/] [--fail-on-missing]
"""

from __future__ import annotations

import re
import sys
from pathlib import Path

import click

from gitea_runner_manager.i18n import _

REPO_ROOT = Path(__file__).resolve().parent.parent.parent
DOCS_DIR = REPO_ROOT / "docs"
CLI_FILE = REPO_ROOT / "src" / "gitea_runner_manager" / "cli.py"

# Major modules that should be documented in tech/architecture.md
REQUIRED_MODULES = [
    "cli.py",
    "runner_manager.py",
    "executor.py",
    "registry.py",
    "i18n.py",
    "exceptions.py",
    "api_clients.py",
    "config.py",
]

# CI scripts that should be documented in tech/ci-cd-workflow.md
REQUIRED_SCRIPTS = [
    "auto_merge.py",
    "release.py",
    "publish.py",
    "review_pr.py",
    "notify_failure.py",
    "post_merge.py",
    "classify_changes.py",
    "discover_runners.py",
]


def extract_cli_commands() -> list[str]:
    """Extract command names from the CLI source file."""
    content = CLI_FILE.read_text()
    commands: list[str] = []
    # Find all @cli.command(...) occurrences, then the next def statement
    for match in re.finditer(r'@cli\.command\b', content):
        # Check for explicit name="..." in the decorator arguments
        decorator_end = content.find(")", match.start())
        decorator_text = content[match.start() : decorator_end + 1]
        name_match = re.search(r'name\s*=\s*"([^"]+)"', decorator_text)
        if name_match:
            commands.append(name_match.group(1))
            continue
        # Find the next def statement after this decorator
        after = content[decorator_end:]
        def_match = re.search(r'def\s+(\w+)\s*\(', after)
        if def_match:
            commands.append(def_match.group(1))
    return commands


def check_command_documented(command: str, docs_content: str) -> bool:
    """Check if a CLI command is documented in the docs content."""
    # Look for the command name as a heading or in code blocks
    patterns = [
        rf"##.*\b{re.escape(command)}\b",
        rf"`grm\s+{re.escape(command)}\b",
        rf"\bgrm\s+{re.escape(command)}\b",
        rf"###.*\b{re.escape(command)}\b",
    ]
    return any(re.search(p, docs_content, re.IGNORECASE) for p in patterns)


def check_module_documented(module: str, docs_content: str) -> bool:
    """Check if a module is mentioned in the docs content."""
    return module in docs_content


@click.command()
@click.option("--docs-dir", default=str(DOCS_DIR), help="Path to the docs directory.")
@click.option(
    "--fail-on-missing",
    is_flag=True,
    default=False,
    help="Exit with non-zero status if any documentation is missing.",
)
def main(docs_dir: str, fail_on_missing: bool) -> None:
    docs_path = Path(docs_dir)
    cli_commands_file = docs_path / "user" / "cli-commands.md"
    architecture_file = docs_path / "tech" / "architecture.md"
    ci_cd_file = docs_path / "tech" / "ci-cd-workflow.md"

    missing: list[str] = []
    total = 0

    # Check CLI commands
    click.echo(_("Checking CLI command documentation..."))
    commands = extract_cli_commands()
    total += len(commands)
    cli_docs = cli_commands_file.read_text() if cli_commands_file.exists() else ""
    for cmd in commands:
        if check_command_documented(cmd, cli_docs):
            click.echo(_("  OK: grm {cmd}", cmd=cmd))
        else:
            click.echo(_("  MISSING: grm {cmd}", cmd=cmd))
            missing.append(f"CLI command: grm {cmd}")

    # Check modules in architecture.md
    click.echo(_("\nChecking module documentation in architecture.md..."))
    total += len(REQUIRED_MODULES)
    arch_docs = architecture_file.read_text() if architecture_file.exists() else ""
    for module in REQUIRED_MODULES:
        if check_module_documented(module, arch_docs):
            click.echo(_("  OK: {module}", module=module))
        else:
            click.echo(_("  MISSING: {module}", module=module))
            missing.append(f"Module: {module}")

    # Check CI scripts in ci-cd-workflow.md
    click.echo(_("\nChecking CI script documentation in ci-cd-workflow.md..."))
    total += len(REQUIRED_SCRIPTS)
    ci_docs = ci_cd_file.read_text() if ci_cd_file.exists() else ""
    for script in REQUIRED_SCRIPTS:
        if check_module_documented(script, ci_docs):
            click.echo(_("  OK: {script}", script=script))
        else:
            click.echo(_("  MISSING: {script}", script=script))
            missing.append(f"CI script: {script}")

    # Report
    covered = total - len(missing)
    percentage = (covered / total * 100) if total > 0 else 100.0
    click.echo(
        _(
            "\nDoc coverage: {covered}/{total} ({pct}%)",
            covered=covered,
            total=total,
            pct=f"{percentage:.0f}%",
        )
    )

    if missing:
        click.echo(_("\nMissing documentation:"))
        for item in missing:
            click.echo(f"  - {item}")

    if missing and fail_on_missing:
        click.echo(_("\nERROR: Documentation coverage is not 100%. Use --fail-on-missing to enforce."))
        sys.exit(1)

    if not missing:
        click.echo(_("\nAll documentation coverage checks passed!"))


if __name__ == "__main__":  # pragma: no cover
    main()