# retoor <retoor@molodetz.nl>
import ast
from pathlib import Path

import sqlglot
from sqlglot.errors import ParseError

from molodetz import config

SQL_PREFIXES = ("SELECT ", "INSERT ", "UPDATE ", "DELETE ", "CREATE ", "PRAGMA ", "WITH ", "ANALYZE")


def _joined_text(node):
    parts = []
    for value in node.values:
        if isinstance(value, ast.Constant):
            parts.append(str(value.value))
        else:
            parts.append("lint_placeholder")
    return "".join(parts)


def _literal_sql(node):
    if isinstance(node, ast.JoinedStr):
        raw = _joined_text(node)
    elif isinstance(node, ast.Constant) and isinstance(node.value, str):
        raw = node.value
    else:
        return None
    text = " ".join(raw.split())
    return text if text.upper().startswith(SQL_PREFIXES) else None


def collect_sql(root=None):
    root = Path(root or config.PKG_ROOT)
    found = []
    for path in sorted(root.rglob("*.py")):
        tree = ast.parse(path.read_text(encoding="utf-8"))
        inner = {id(value) for node in ast.walk(tree) if isinstance(node, ast.JoinedStr) for value in node.values}
        for node in ast.walk(tree):
            if id(node) in inner:
                continue
            sql = _literal_sql(node)
            if sql:
                found.append((path, node.lineno, sql))
    return found


def lint(root=None):
    problems = []
    for path, line, sql in collect_sql(root):
        if sql.upper().startswith(("PRAGMA", "ANALYZE")):
            continue
        try:
            sqlglot.parse_one(sql, read="sqlite")
        except ParseError as exc:
            problems.append(f"{path}:{line}: {str(exc).splitlines()[0]}")
    return problems