from __future__ import annotations

from pathlib import Path

from depaudit.parsers import Parser, ParsedManifest


class GoParser(Parser):
    language = "go"

    def can_parse(self, file_path: Path) -> bool:
        return file_path.name == "go.mod"

    def parse(self, file_path: Path) -> ParsedManifest:
        content = file_path.read_text(encoding="utf-8")
        lines = content.split("\n")

        manifest = ParsedManifest(
            language=self.language,
            file_path=file_path,
        )

        i = 0
        in_require_block = False
        current_line_indent = 0

        while i < len(lines):
            line = lines[i].strip()

            if not line or line.startswith("//"):
                i += 1
                continue

            if line.startswith("module"):
                manifest.project_name = line.split()[1].strip()
            elif line.startswith("go"):
                pass
            elif line.startswith("require"):
                in_require_block = True
                current_line_indent = len(lines[i]) - len(lines[i].lstrip())
                self._parse_require(line, file_path, manifest)
            elif in_require_block:
                current_indent = len(lines[i]) - len(lines[i].lstrip())
                if current_indent > current_line_indent and not line.startswith("//"):
                    self._parse_require(lines[i], file_path, manifest)
                else:
                    in_require_block = False

            i += 1

        return manifest

    def _parse_require(
        self, line: str, file_path: Path, manifest: ParsedManifest
    ) -> None:
        content = line.strip()
        if content.startswith("//"):
            return

        if content.startswith("require"):
            content = content[len("require"):].strip()
            if content.startswith("("):
                content = content[1:]
            if content.endswith(")"):
                content = content[:-1]

        if not content:
            return

        parts = content.split()
        i = 0
        while i < len(parts):
            if parts[i].startswith("//"):
                break
            name = parts[i]
            version = ""
            if i + 1 < len(parts) and not parts[i + 1].startswith("/"):
                version = parts[i + 1]
                i += 2
            else:
                i += 1

            if name:
                indirect = "// indirect" in line or "(// indirect)" in line or "(indirect)" in line
                manifest.dependencies.append(
                    self._create_dependency(file_path, name, version, indirect=indirect)
                )