"""FileUploadConfig marshmallow schemas."""

from typing import Any, Dict

from abacus_common_logic.marshalling.custom_fields import ma
from marshmallow import ValidationError, validates_schema

from abacus_file_upload.constants import (
    S3_MAX_CHUNK_SIZE_BYTES,
    S3_MAX_FILE_SIZE_BYTES,
    S3_MAX_MULTIPART_THRESHOLD_BYTES,
    S3_MIN_CHUNK_SIZE_BYTES,
    S3_MIN_MULTIPART_THRESHOLD_BYTES,
    UPLOAD_TYPES,
)
from abacus_file_upload.utils import format_bytes

# Validation helper functions


def validate_file_types(file_types: list) -> None:
    """Validate allowed_file_types list.

    Args:
        file_types: List of file type strings

    Raises:
        ValidationError: If file types are invalid or contain leading dots
    """
    if not file_types:  # Empty list
        raise ValidationError(
            'allowed_file_types cannot be empty. Use null to allow all types.',
            field_name='allowed_file_types',
        )

    for file_type in file_types:
        if not file_type or not isinstance(file_type, str):
            raise ValidationError(
                'All file types must be non-empty strings',
                field_name='allowed_file_types',
            )
        if file_type.startswith('.'):
            raise ValidationError(
                'File types should not include leading dot (use "csv" not ".csv")',
                field_name='allowed_file_types',
            )


def validate_max_file_size(max_size: int) -> None:
    """Validate that max_file_size_bytes is within S3 limits.

    Args:
        max_size: Maximum file size in bytes

    Raises:
        ValidationError: If max file size is outside S3 limits (0 bytes - 5 TB)
    """
    if max_size < 0:
        raise ValidationError(
            'max_file_size_bytes must be >= 0 bytes',
            field_name='max_file_size_bytes',
        )
    if max_size > S3_MAX_FILE_SIZE_BYTES:
        max_file_size = format_bytes(S3_MAX_FILE_SIZE_BYTES)
        raise ValidationError(
            f'max_file_size_bytes must be <= {S3_MAX_FILE_SIZE_BYTES} bytes ({max_file_size})',
            field_name='max_file_size_bytes',
        )


def validate_min_chunk_size(min_chunk: int) -> None:
    """Validate min_multipart_chunk_size_bytes is within S3 limits.

    Args:
        min_chunk: Minimum chunk size in bytes

    Raises:
        ValidationError: If chunk size is outside S3 limits (5MB - 5GB)
    """
    if min_chunk < S3_MIN_CHUNK_SIZE_BYTES:
        min_chunk_size = format_bytes(S3_MIN_CHUNK_SIZE_BYTES)
        raise ValidationError(
            f'min_multipart_chunk_size_bytes must be >= {S3_MIN_CHUNK_SIZE_BYTES} bytes ({min_chunk_size})',
            field_name='min_multipart_chunk_size_bytes',
        )
    if min_chunk > S3_MAX_CHUNK_SIZE_BYTES:
        max_chunk_size = format_bytes(S3_MAX_CHUNK_SIZE_BYTES)
        raise ValidationError(
            f'min_multipart_chunk_size_bytes must be <= {S3_MAX_CHUNK_SIZE_BYTES} bytes ({max_chunk_size})',
            field_name='min_multipart_chunk_size_bytes',
        )


def validate_multipart_threshold(threshold: int) -> None:
    """Validate that threshold is within S3 limits.

    Args:
        threshold: Multipart threshold size in bytes

    Raises:
        ValidationError: If threshold is outside S3 limits (5MB - 5 GB)
    """
    if threshold < S3_MIN_MULTIPART_THRESHOLD_BYTES:
        min_threshold = format_bytes(S3_MIN_MULTIPART_THRESHOLD_BYTES)
        raise ValidationError(
            f'multipart_threshold_bytes must be >= {S3_MIN_MULTIPART_THRESHOLD_BYTES} bytes ({min_threshold})',
            field_name='multipart_threshold_bytes',
        )
    if threshold > S3_MAX_MULTIPART_THRESHOLD_BYTES:
        max_threshold = format_bytes(S3_MAX_MULTIPART_THRESHOLD_BYTES)
        raise ValidationError(
            f'multipart_threshold_bytes must be <= {S3_MAX_MULTIPART_THRESHOLD_BYTES} bytes ({max_threshold})',
            field_name='multipart_threshold_bytes',
        )


def validate_file_upload_config_data(data: Dict[str, Any]) -> None:
    """Validate file upload config data constraints.

    Args:
        data: Dictionary of config data to validate

    Raises:
        ValidationError: If any validation fails
    """
    # Validate min_multipart_chunk_size_bytes
    min_chunk = data.get('min_multipart_chunk_size_bytes')
    if min_chunk is not None:
        validate_min_chunk_size(min_chunk)

    # Validate max_file_size_bytes
    max_size = data.get('max_file_size_bytes')
    if max_size is not None:
        validate_max_file_size(max_size)

    # Validate multipart_threshold_bytes
    threshold = data.get('multipart_threshold_bytes')
    if threshold is not None:
        validate_multipart_threshold(threshold)

    # Validate allowed_file_types
    allowed_types = data.get('allowed_file_types')
    if allowed_types is not None:
        validate_file_types(allowed_types)


class FileUploadConfigDetailSchema(ma.Schema):
    """FileUploadConfig detail response schema."""

    file_upload_config_id = ma.IntegerId(
        metadata={
            'description': 'Unique identifier for the upload configuration',
            'example': 1,
        }
    )
    upload_type = ma.Enum(
        options=UPLOAD_TYPES,
        metadata={
            'description': 'Type of upload this configuration applies to',
            'example': 'adjustments',
        },
    )
    s3_key_template = ma.NonemptyString(
        metadata={
            'description': 'S3 key template for organizing uploaded files. Supports variables like {date}, {uuid}',
            'example': 'uploads/{date}/{uuid}.{ext}',
        }
    )
    allowed_file_types = ma.List(
        ma.String(),
        allow_none=True,
        metadata={
            'description': 'List of allowed file extensions (without leading dot)',
            'example': ['xlsx', 'csv', 'txt'],
        },
    )
    max_file_size_bytes = ma.Integer(
        metadata={
            'description': 'Maximum allowed file size in bytes (up to 5TB)',
            'example': 104857600,  # 100MB
        }
    )
    multipart_threshold_bytes = ma.Integer(
        allow_none=True,
        metadata={
            'description': 'File size threshold for using multipart upload (5MB - 5GB)',
            'example': 104857600,  # 100MB
        },
    )
    min_multipart_chunk_size_bytes = ma.Integer(
        allow_none=True,
        metadata={
            'description': 'Minimum chunk size for multipart uploads (5MB - 5GB)',
            'example': 5242880,  # 5MB
        },
    )
    description = ma.String(
        allow_none=True,
        metadata={
            'description': 'Description of this upload configuration',
            'example': 'Configuration for adjustment file uploads',
        },
    )
    event_name = ma.String(
        allow_none=True,
        metadata={
            'description': 'event can trigger a lambda or an Airflow DAG',
            'example': 'event for adjustment file approve',
        },
    )


class FileUploadConfigDetailVerboseSchema(FileUploadConfigDetailSchema):
    """FileUploadConfig detail response schema with audit fields."""

    created_at = ma.FormattedDateTime(
        metadata={
            'description': 'Timestamp when the configuration was created',
            'example': '2025-11-24T04:35:43.396Z',
        }
    )
    created_by = ma.String(
        metadata={
            'description': 'User identity ID of the user who created the configuration',
            'example': '12345',
        }
    )
    last_modified = ma.FormattedDateTime(
        metadata={
            'description': 'Timestamp when the configuration was last modified',
            'example': '2025-11-24T04:36:15.123Z',
        }
    )
    last_modified_by = ma.String(
        metadata={
            'description': 'User identity ID of the user who last modified the configuration',
            'example': '12345',
        }
    )
    deleted_at = ma.FormattedDateTime(
        allow_none=True,
        metadata={
            'description': 'Timestamp when the configuration was deleted (soft delete)',
            'example': None,
        },
    )
    deleted_by = ma.String(
        allow_none=True,
        metadata={
            'description': 'User identity ID of the user who deleted the configuration',
            'example': '67890',
        },
    )


class FileUploadConfigPostSchema(ma.Schema):
    """FileUploadConfig POST request schema."""

    upload_type = ma.Enum(
        options=UPLOAD_TYPES,
        required=True,
        metadata={
            'description': 'Type of upload this configuration applies to',
            'example': 'adjustments',
        },
    )
    s3_key_template = ma.NonemptyString(
        required=True,
        metadata={
            'description': 'S3 key template for organizing uploaded files. Supports variables like {date}, {uuid}, {ext}',
            'example': 'uploads/{date}/{uuid}.{ext}',
        },
    )
    allowed_file_types = ma.List(
        ma.String(),
        allow_none=True,
        metadata={
            'description': 'List of allowed file extensions (without leading dot). Null allows all types',
            'example': ['xlsx', 'csv', 'txt'],
        },
    )
    max_file_size_bytes = ma.Integer(
        metadata={
            'description': 'Maximum allowed file size in bytes (0 to 5TB)',
            'example': 104857600,  # 100MB
        }
    )
    multipart_threshold_bytes = ma.Integer(
        allow_none=True,
        metadata={
            'description': 'File size threshold for using multipart upload. Must be between 5MB and 5GB',
            'example': 104857600,  # 100MB
        },
    )
    min_multipart_chunk_size_bytes = ma.Integer(
        allow_none=True,
        metadata={
            'description': 'Minimum chunk size for multipart uploads. Must be between 5MB and 5GB',
            'example': 5242880,  # 5MB
        },
    )
    description = ma.String(
        allow_none=True,
        metadata={
            'description': 'Description of this upload configuration',
            'example': 'Configuration for adjustment file uploads',
        },
    )
    event_name = ma.String(
        allow_none=True,
        metadata={
            'description': 'An event that can be configured to trigger a lambda or an Airflow DAG',
            'example': 'event for adjustment file approve',
        },
    )

    @validates_schema
    def validate_data(self, data, **kwargs):
        """Validate file size constraints and relationships."""
        validate_file_upload_config_data(data)


class FileUploadConfigPutSchema(ma.Schema):
    """FileUploadConfig PUT request schema."""

    s3_key_template = ma.NonemptyString(
        metadata={
            'description': 'S3 key template for organizing uploaded files. Supports variables like {date}, {uuid}, {ext}',
            'example': 'uploads/{date}/{uuid}.{ext}',
        }
    )
    allowed_file_types = ma.List(
        ma.String(),
        allow_none=True,
        metadata={
            'description': 'List of allowed file extensions (without leading dot). Null allows all types',
            'example': ['xlsx', 'csv', 'txt'],
        },
    )
    max_file_size_bytes = ma.Integer(
        metadata={
            'description': 'Maximum allowed file size in bytes (0 to 5TB)',
            'example': 104857600,  # 100MB
        }
    )
    multipart_threshold_bytes = ma.Integer(
        allow_none=True,
        metadata={
            'description': 'File size threshold for using multipart upload. Must be between 5MB and 5GB',
            'example': 104857600,  # 100MB
        },
    )
    min_multipart_chunk_size_bytes = ma.Integer(
        allow_none=True,
        metadata={
            'description': 'Minimum chunk size for multipart uploads. Must be between 5MB and 5GB',
            'example': 5242880,  # 5MB
        },
    )
    description = ma.String(
        allow_none=True,
        metadata={
            'description': 'Description of this upload configuration',
            'example': 'Updated configuration for adjustment file uploads',
        },
    )
    event_name = ma.String(
        allow_none=True,
        metadata={
            'description': 'An event that can be configured to trigger a lambda or an Airflow DAG',
            'example': 'event for adjustment file approve',
        },
    )

    @validates_schema
    def validate_data(self, data, **kwargs):
        """Validate file size constraints and relationships."""
        validate_file_upload_config_data(data)