"""Structured error types for GnommoEditor pipeline."""

from dataclasses import dataclass
from pathlib import Path
from typing import Optional


class GnommoError(Exception):
    """Base exception for all GnommoEditor errors."""
    pass


@dataclass
class ValidationIssue:
    """A single validation issue with location context."""
    message: str
    file: Optional[Path] = None
    line: Optional[int] = None

    def __str__(self) -> str:
        parts = []
        if self.file:
            parts.append(str(self.file))
        if self.line is not None:
            parts.append(f"line {self.line}")
        location = ":".join(parts) if parts else "project"
        return f"[{location}] {self.message}"


class ParseError(GnommoError):
    """Error during parsing of input files."""

    def __init__(self, message: str, file: Optional[Path] = None, line: Optional[int] = None):
        self.issue = ValidationIssue(message, file, line)
        super().__init__(str(self.issue))


class ValidationError(GnommoError):
    """Error during validation stage. Can contain multiple issues."""

    def __init__(self, issues: list[ValidationIssue]):
        self.issues = issues
        message = f"Validation failed with {len(issues)} error(s):\n"
        message += "\n".join(f"  - {issue}" for issue in issues)
        super().__init__(message)


class RenderError(GnommoError):
    """Error during rendering stage."""

    def __init__(self, message: str, command: Optional[str] = None, stderr: Optional[str] = None):
        self.command = command
        self.stderr = stderr
        full_message = message
        if command:
            full_message += f"\nCommand: {command}"
        if stderr:
            full_message += f"\nFFmpeg output:\n{stderr}"
        super().__init__(full_message)