"""
Data models for issue context estimation.

Defines enums and data classes used by the context estimator.
"""

from dataclasses import dataclass
from enum import Enum
from typing import Optional


class ComplexityLevel(Enum):
    """Implementation complexity levels with token allocations."""

    LOW = 10000  # Simple, straightforward implementation
    MEDIUM = 20000  # Moderate complexity, some edge cases
    HIGH = 30000  # Complex logic, many edge cases, algorithms


class TestLevel(Enum):
    """Test requirement levels with token allocations."""

    LOW = 5000  # Basic unit tests
    MEDIUM = 10000  # Unit + integration tests
    HIGH = 15000  # Unit + integration + E2E tests


class DocLevel(Enum):
    """Documentation requirement levels with token allocations."""

    NONE = 0  # No documentation needed
    LIGHT = 2000  # Inline comments, basic docstrings
    MEDIUM = 3000  # API docs, usage examples
    HEAVY = 5000  # Comprehensive docs, guides, tutorials


@dataclass
class EstimationInput:
    """
    Input parameters for context estimation.

    Attributes:
        files_to_modify: Number of files expected to be modified
        implementation_complexity: Complexity level of implementation
        test_requirements: Level of testing required
        documentation: Level of documentation required
    """

    files_to_modify: int
    implementation_complexity: ComplexityLevel
    test_requirements: TestLevel
    documentation: DocLevel

    def __post_init__(self):
        """Validate input parameters."""
        if self.files_to_modify < 0:
            raise ValueError("files_to_modify must be >= 0")

        if not isinstance(self.implementation_complexity, ComplexityLevel):
            raise TypeError(
                f"implementation_complexity must be ComplexityLevel, "
                f"got {type(self.implementation_complexity)}"
            )

        if not isinstance(self.test_requirements, TestLevel):
            raise TypeError(
                f"test_requirements must be TestLevel, "
                f"got {type(self.test_requirements)}"
            )

        if not isinstance(self.documentation, DocLevel):
            raise TypeError(
                f"documentation must be DocLevel, " f"got {type(self.documentation)}"
            )


@dataclass
class EstimationResult:
    """
    Result of context estimation.

    Contains breakdown of token allocation by category and total estimate
    with safety buffer applied.

    Attributes:
        files_context: Tokens allocated for file context (files × 7000)
        implementation_tokens: Tokens allocated for implementation
        test_tokens: Tokens allocated for tests
        doc_tokens: Tokens allocated for documentation
        base_estimate: Sum of all components before buffer
        buffer_tokens: Safety buffer (30% of base)
        total_estimate: Final estimate with buffer applied
        recommended_agent: Suggested agent based on total (haiku/sonnet/opus)
    """

    files_context: int
    implementation_tokens: int
    test_tokens: int
    doc_tokens: int
    base_estimate: int
    buffer_tokens: int
    total_estimate: int
    recommended_agent: str

    def to_dict(self) -> dict:
        """Convert result to dictionary for serialization."""
        return {
            "files_context": self.files_context,
            "implementation_tokens": self.implementation_tokens,
            "test_tokens": self.test_tokens,
            "doc_tokens": self.doc_tokens,
            "base_estimate": self.base_estimate,
            "buffer_tokens": self.buffer_tokens,
            "total_estimate": self.total_estimate,
            "recommended_agent": self.recommended_agent,
        }


@dataclass
class ValidationResult:
    """
    Result of validating estimate against actual usage.

    Used for historical validation and accuracy tracking.

    Attributes:
        issue_number: Issue number validated
        estimated_tokens: Estimated context tokens
        actual_tokens: Actual tokens used (if known)
        percentage_error: Percentage error (estimated vs actual)
        within_tolerance: Whether error is within ±20% tolerance
        notes: Optional notes about validation
    """

    issue_number: int
    estimated_tokens: int
    actual_tokens: Optional[int] = None
    percentage_error: Optional[float] = None
    within_tolerance: Optional[bool] = None
    notes: Optional[str] = None

    def __post_init__(self):
        """Calculate derived fields if actual_tokens provided."""
        if self.actual_tokens is not None:
            self.percentage_error = abs(
                self.estimated_tokens - self.actual_tokens
            ) / self.actual_tokens
            self.within_tolerance = self.percentage_error <= 0.20

    def to_dict(self) -> dict:
        """Convert result to dictionary for serialization."""
        return {
            "issue_number": self.issue_number,
            "estimated_tokens": self.estimated_tokens,
            "actual_tokens": self.actual_tokens,
            "percentage_error": (
                f"{self.percentage_error:.2%}" if self.percentage_error else None
            ),
            "within_tolerance": self.within_tolerance,
            "notes": self.notes,
        }