# app/api/v1/admin/settings.py
"""
Platform settings management endpoints.

Provides endpoints for:
- Viewing all platform settings
- Creating/updating settings
- Managing configuration by category
- Email configuration status and testing
"""

import logging

from fastapi import APIRouter, Depends, Query
from pydantic import BaseModel, EmailStr
from sqlalchemy.orm import Session

from app.api.deps import get_current_admin_api
from app.core.config import settings as app_settings
from app.core.database import get_db
from app.exceptions import ConfirmationRequiredException, ResourceNotFoundException
from app.services.admin_audit_service import admin_audit_service
from app.services.admin_settings_service import admin_settings_service
from models.schema.auth import UserContext
from models.schema.admin import (
    AdminSettingCreate,
    AdminSettingDefaultResponse,
    AdminSettingListResponse,
    AdminSettingResponse,
    AdminSettingUpdate,
    PublicDisplaySettingsResponse,
    RowsPerPageResponse,
    RowsPerPageUpdateResponse,
)

router = APIRouter(prefix="/settings")
logger = logging.getLogger(__name__)


@router.get("", response_model=AdminSettingListResponse)
def get_all_settings(
    category: str | None = Query(None, description="Filter by category"),
    is_public: bool | None = Query(None, description="Filter by public flag"),
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """
    Get all platform settings.

    Can be filtered by category (system, security, marketplace, notifications)
    and by public flag (settings that can be exposed to frontend).
    """
    settings = admin_settings_service.get_all_settings(db, category, is_public)

    return AdminSettingListResponse(
        settings=settings, total=len(settings), category=category
    )


@router.get("/categories")
def get_setting_categories(
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """Get list of all setting categories."""
    # This could be enhanced to return counts per category
    return {
        "categories": [
            "system",
            "security",
            "marketplace",
            "notifications",
            "integrations",
            "payments",
        ]
    }


@router.get("/{key}", response_model=AdminSettingResponse | AdminSettingDefaultResponse)
def get_setting(
    key: str,
    default: str | None = Query(None, description="Default value if setting not found"),
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
) -> AdminSettingResponse | AdminSettingDefaultResponse:
    """Get specific setting by key.

    If `default` is provided and the setting doesn't exist, returns a response
    with the default value instead of 404.
    """
    setting = admin_settings_service.get_setting_by_key(db, key)

    if not setting:
        if default is not None:
            # Return default value without creating the setting
            return AdminSettingDefaultResponse(key=key, value=default, exists=False)
        raise ResourceNotFoundException(resource_type="Setting", identifier=key)

    return AdminSettingResponse.model_validate(setting)


@router.post("", response_model=AdminSettingResponse)
def create_setting(
    setting_data: AdminSettingCreate,
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """
    Create new platform setting.

    Setting keys should be lowercase with underscores (e.g., max_vendors_allowed).
    """
    result = admin_settings_service.create_setting(
        db=db, setting_data=setting_data, admin_user_id=current_admin.id
    )

    # Log action
    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="create_setting",
        target_type="setting",
        target_id=setting_data.key,
        details={
            "category": setting_data.category,
            "value_type": setting_data.value_type,
        },
    )
    db.commit()

    return result


@router.put("/{key}", response_model=AdminSettingResponse)
def update_setting(
    key: str,
    update_data: AdminSettingUpdate,
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """Update existing setting value."""
    old_value = admin_settings_service.get_setting_value(db, key)

    result = admin_settings_service.update_setting(
        db=db, key=key, update_data=update_data, admin_user_id=current_admin.id
    )

    # Log action
    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="update_setting",
        target_type="setting",
        target_id=key,
        details={"old_value": str(old_value), "new_value": update_data.value},
    )
    db.commit()

    return result


@router.post("/upsert", response_model=AdminSettingResponse)
def upsert_setting(
    setting_data: AdminSettingCreate,
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """
    Create or update setting (upsert).

    If setting exists, updates its value. If not, creates new setting.
    """
    result = admin_settings_service.upsert_setting(
        db=db, setting_data=setting_data, admin_user_id=current_admin.id
    )

    # Log action
    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="upsert_setting",
        target_type="setting",
        target_id=setting_data.key,
        details={"category": setting_data.category},
    )
    db.commit()

    return result


# ============================================================================
# CONVENIENCE ENDPOINTS FOR COMMON SETTINGS
# ============================================================================


@router.get("/display/rows-per-page", response_model=RowsPerPageResponse)
def get_rows_per_page(
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
) -> RowsPerPageResponse:
    """Get the platform-wide rows per page setting."""
    value = admin_settings_service.get_setting_value(db, "rows_per_page", default="20")
    return RowsPerPageResponse(rows_per_page=int(value))


@router.put("/display/rows-per-page", response_model=RowsPerPageUpdateResponse)
def set_rows_per_page(
    rows: int = Query(..., ge=10, le=100, description="Rows per page (10-100)"),
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
) -> RowsPerPageUpdateResponse:
    """
    Set the platform-wide rows per page setting.

    Valid values: 10, 20, 50, 100
    """
    valid_values = [10, 20, 50, 100]
    if rows not in valid_values:
        # Round to nearest valid value
        rows = min(valid_values, key=lambda x: abs(x - rows))

    setting_data = AdminSettingCreate(
        key="rows_per_page",
        value=str(rows),
        value_type="integer",
        category="display",
        description="Default number of rows per page in admin tables",
        is_public=True,
    )

    admin_settings_service.upsert_setting(
        db=db, setting_data=setting_data, admin_user_id=current_admin.id
    )

    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="update_setting",
        target_type="setting",
        target_id="rows_per_page",
        details={"value": rows},
    )
    db.commit()

    return RowsPerPageUpdateResponse(
        rows_per_page=rows, message="Rows per page setting updated"
    )


@router.get("/display/public", response_model=PublicDisplaySettingsResponse)
def get_public_display_settings(
    db: Session = Depends(get_db),
) -> PublicDisplaySettingsResponse:
    """
    Get public display settings (no auth required).

    Returns settings that can be used by frontend without admin auth.
    """
    rows_per_page = admin_settings_service.get_setting_value(
        db, "rows_per_page", default="20"
    )

    return PublicDisplaySettingsResponse(rows_per_page=int(rows_per_page))


@router.delete("/{key}")
def delete_setting(
    key: str,
    confirm: bool = Query(False, description="Must be true to confirm deletion"),
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """
    Delete platform setting.

    Requires confirmation parameter.
    WARNING: Deleting settings may affect platform functionality.
    """
    if not confirm:
        raise ConfirmationRequiredException(
            operation="delete_setting",
            message="Deletion requires confirmation parameter: confirm=true",
        )

    message = admin_settings_service.delete_setting(
        db=db, key=key, admin_user_id=current_admin.id
    )

    # Log action
    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="delete_setting",
        target_type="setting",
        target_id=key,
        details={},
    )
    db.commit()

    return {"message": message}


# ============================================================================
# EMAIL CONFIGURATION ENDPOINTS
# ============================================================================

# Email setting keys stored in admin_settings table
EMAIL_SETTING_KEYS = {
    "email_provider": "smtp",
    "email_from_address": "",
    "email_from_name": "",
    "email_reply_to": "",
    "smtp_host": "",
    "smtp_port": "587",
    "smtp_user": "",
    "smtp_password": "",
    "smtp_use_tls": "true",
    "smtp_use_ssl": "false",
    "sendgrid_api_key": "",
    "mailgun_api_key": "",
    "mailgun_domain": "",
    "aws_access_key_id": "",
    "aws_secret_access_key": "",
    "aws_region": "eu-west-1",
    "email_enabled": "true",
    "email_debug": "false",
}


def get_email_setting(db: Session, key: str) -> str | None:
    """Get email setting from database, returns None if not set."""
    setting = admin_settings_service.get_setting_by_key(db, key)
    return setting.value if setting else None


def get_effective_email_config(db: Session) -> dict:
    """
    Get effective email configuration.

    Priority: Database settings > Environment variables
    """
    config = {}

    # Provider
    db_provider = get_email_setting(db, "email_provider")
    config["provider"] = db_provider if db_provider else app_settings.email_provider

    # From settings
    db_from_email = get_email_setting(db, "email_from_address")
    config["from_email"] = db_from_email if db_from_email else app_settings.email_from_address

    db_from_name = get_email_setting(db, "email_from_name")
    config["from_name"] = db_from_name if db_from_name else app_settings.email_from_name

    db_reply_to = get_email_setting(db, "email_reply_to")
    config["reply_to"] = db_reply_to if db_reply_to else app_settings.email_reply_to

    # SMTP settings
    db_smtp_host = get_email_setting(db, "smtp_host")
    config["smtp_host"] = db_smtp_host if db_smtp_host else app_settings.smtp_host

    db_smtp_port = get_email_setting(db, "smtp_port")
    config["smtp_port"] = int(db_smtp_port) if db_smtp_port else app_settings.smtp_port

    db_smtp_user = get_email_setting(db, "smtp_user")
    config["smtp_user"] = db_smtp_user if db_smtp_user else app_settings.smtp_user

    db_smtp_password = get_email_setting(db, "smtp_password")
    config["smtp_password"] = db_smtp_password if db_smtp_password else app_settings.smtp_password

    db_smtp_use_tls = get_email_setting(db, "smtp_use_tls")
    config["smtp_use_tls"] = db_smtp_use_tls.lower() in ("true", "1", "yes") if db_smtp_use_tls else app_settings.smtp_use_tls

    db_smtp_use_ssl = get_email_setting(db, "smtp_use_ssl")
    config["smtp_use_ssl"] = db_smtp_use_ssl.lower() in ("true", "1", "yes") if db_smtp_use_ssl else app_settings.smtp_use_ssl

    # SendGrid
    db_sendgrid_key = get_email_setting(db, "sendgrid_api_key")
    config["sendgrid_api_key"] = db_sendgrid_key if db_sendgrid_key else app_settings.sendgrid_api_key

    # Mailgun
    db_mailgun_key = get_email_setting(db, "mailgun_api_key")
    config["mailgun_api_key"] = db_mailgun_key if db_mailgun_key else app_settings.mailgun_api_key

    db_mailgun_domain = get_email_setting(db, "mailgun_domain")
    config["mailgun_domain"] = db_mailgun_domain if db_mailgun_domain else app_settings.mailgun_domain

    # AWS SES
    db_aws_key = get_email_setting(db, "aws_access_key_id")
    config["aws_access_key_id"] = db_aws_key if db_aws_key else app_settings.aws_access_key_id

    db_aws_secret = get_email_setting(db, "aws_secret_access_key")
    config["aws_secret_access_key"] = db_aws_secret if db_aws_secret else app_settings.aws_secret_access_key

    db_aws_region = get_email_setting(db, "aws_region")
    config["aws_region"] = db_aws_region if db_aws_region else app_settings.aws_region

    # Behavior
    db_enabled = get_email_setting(db, "email_enabled")
    config["enabled"] = db_enabled.lower() in ("true", "1", "yes") if db_enabled else app_settings.email_enabled

    db_debug = get_email_setting(db, "email_debug")
    config["debug"] = db_debug.lower() in ("true", "1", "yes") if db_debug else app_settings.email_debug

    # Track source for each field (DB override or .env)
    config["_sources"] = {}
    for key in ["provider", "from_email", "from_name", "smtp_host", "smtp_port"]:
        db_key = "email_provider" if key == "provider" else ("email_from_address" if key == "from_email" else ("email_from_name" if key == "from_name" else key))
        config["_sources"][key] = "database" if get_email_setting(db, db_key) else "env"

    return config


class EmailStatusResponse(BaseModel):
    """Platform email configuration status."""

    provider: str
    from_email: str
    from_name: str
    reply_to: str | None = None
    smtp_host: str | None = None
    smtp_port: int | None = None
    smtp_user: str | None = None
    mailgun_domain: str | None = None
    aws_region: str | None = None
    debug: bool
    enabled: bool
    is_configured: bool
    has_db_overrides: bool = False


class EmailSettingsUpdate(BaseModel):
    """Update email settings."""

    provider: str | None = None
    from_email: EmailStr | None = None
    from_name: str | None = None
    reply_to: EmailStr | None = None
    # SMTP
    smtp_host: str | None = None
    smtp_port: int | None = None
    smtp_user: str | None = None
    smtp_password: str | None = None
    smtp_use_tls: bool | None = None
    smtp_use_ssl: bool | None = None
    # SendGrid
    sendgrid_api_key: str | None = None
    # Mailgun
    mailgun_api_key: str | None = None
    mailgun_domain: str | None = None
    # AWS SES
    aws_access_key_id: str | None = None
    aws_secret_access_key: str | None = None
    aws_region: str | None = None
    # Behavior
    enabled: bool | None = None
    debug: bool | None = None


class TestEmailRequest(BaseModel):
    """Request body for test email."""

    to_email: EmailStr


class TestEmailResponse(BaseModel):
    """Response for test email."""

    success: bool
    message: str


@router.get("/email/status", response_model=EmailStatusResponse)
def get_email_status(
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
) -> EmailStatusResponse:
    """
    Get platform email configuration status.

    Returns the effective email configuration (DB overrides > .env).
    Sensitive values (passwords, API keys) are NOT exposed.
    """
    config = get_effective_email_config(db)
    provider = config["provider"].lower()

    # Determine if email is configured based on provider
    is_configured = False
    if provider == "smtp":
        is_configured = bool(config["smtp_host"] and config["smtp_host"] != "localhost")
    elif provider == "sendgrid":
        is_configured = bool(config["sendgrid_api_key"])
    elif provider == "mailgun":
        is_configured = bool(config["mailgun_api_key"] and config["mailgun_domain"])
    elif provider == "ses":
        is_configured = bool(config["aws_access_key_id"] and config["aws_secret_access_key"])

    # Check if any DB overrides exist
    has_db_overrides = any(v == "database" for v in config["_sources"].values())

    return EmailStatusResponse(
        provider=provider,
        from_email=config["from_email"],
        from_name=config["from_name"],
        reply_to=config["reply_to"] or None,
        smtp_host=config["smtp_host"] if provider == "smtp" else None,
        smtp_port=config["smtp_port"] if provider == "smtp" else None,
        smtp_user=config["smtp_user"] if provider == "smtp" else None,
        mailgun_domain=config["mailgun_domain"] if provider == "mailgun" else None,
        aws_region=config["aws_region"] if provider == "ses" else None,
        debug=config["debug"],
        enabled=config["enabled"],
        is_configured=is_configured,
        has_db_overrides=has_db_overrides,
    )


@router.put("/email/settings")
def update_email_settings(
    settings_update: EmailSettingsUpdate,
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """
    Update platform email settings.

    Settings are stored in the database and override .env values.
    Only non-null values are updated.
    """
    from models.schema.admin import AdminSettingCreate

    updated_keys = []

    # Map request fields to database keys
    field_mappings = {
        "provider": ("email_provider", "string"),
        "from_email": ("email_from_address", "string"),
        "from_name": ("email_from_name", "string"),
        "reply_to": ("email_reply_to", "string"),
        "smtp_host": ("smtp_host", "string"),
        "smtp_port": ("smtp_port", "integer"),
        "smtp_user": ("smtp_user", "string"),
        "smtp_password": ("smtp_password", "string"),
        "smtp_use_tls": ("smtp_use_tls", "boolean"),
        "smtp_use_ssl": ("smtp_use_ssl", "boolean"),
        "sendgrid_api_key": ("sendgrid_api_key", "string"),
        "mailgun_api_key": ("mailgun_api_key", "string"),
        "mailgun_domain": ("mailgun_domain", "string"),
        "aws_access_key_id": ("aws_access_key_id", "string"),
        "aws_secret_access_key": ("aws_secret_access_key", "string"),
        "aws_region": ("aws_region", "string"),
        "enabled": ("email_enabled", "boolean"),
        "debug": ("email_debug", "boolean"),
    }

    # Sensitive fields that should be marked as encrypted
    sensitive_keys = {
        "smtp_password", "sendgrid_api_key", "mailgun_api_key",
        "aws_access_key_id", "aws_secret_access_key"
    }

    for field, (db_key, value_type) in field_mappings.items():
        value = getattr(settings_update, field, None)
        if value is not None:
            # Convert value to string for storage
            if value_type == "boolean":
                str_value = "true" if value else "false"
            elif value_type == "integer":
                str_value = str(value)
            else:
                str_value = str(value)

            # Create or update setting
            setting_data = AdminSettingCreate(
                key=db_key,
                value=str_value,
                value_type=value_type,
                category="email",
                description=f"Email setting: {field}",
                is_encrypted=db_key in sensitive_keys,
                is_public=False,
            )

            admin_settings_service.upsert_setting(db, setting_data, current_admin.id)
            updated_keys.append(field)

    # Log action
    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="update_email_settings",
        target_type="email_settings",
        target_id="platform",
        details={"updated_keys": updated_keys},
    )
    db.commit()

    logger.info(f"Email settings updated by admin {current_admin.id}: {updated_keys}")

    return {
        "success": True,
        "message": f"Updated {len(updated_keys)} email setting(s)",
        "updated_keys": updated_keys,
    }


@router.delete("/email/settings")
def reset_email_settings(
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
):
    """
    Reset email settings to use .env values.

    Deletes all email settings from the database, reverting to .env configuration.
    """
    deleted_count = 0

    for key in EMAIL_SETTING_KEYS:
        setting = admin_settings_service.get_setting_by_key(db, key)
        if setting:
            # Use service method for deletion (API-002 compliance)
            admin_settings_service.delete_setting(db, key, current_admin.id)
            deleted_count += 1

    # Log action
    admin_audit_service.log_action(
        db=db,
        admin_user_id=current_admin.id,
        action="reset_email_settings",
        target_type="email_settings",
        target_id="platform",
        details={"deleted_count": deleted_count},
    )
    db.commit()

    logger.info(f"Email settings reset by admin {current_admin.id}, deleted {deleted_count} settings")

    return {
        "success": True,
        "message": f"Reset {deleted_count} email setting(s) to .env defaults",
    }


@router.post("/email/test", response_model=TestEmailResponse)
def send_test_email(
    request: TestEmailRequest,
    db: Session = Depends(get_db),
    current_admin: UserContext = Depends(get_current_admin_api),
) -> TestEmailResponse:
    """
    Send a test email using the platform email configuration.

    This tests the email provider configuration from environment variables.
    """
    from app.services.email_service import EmailService

    try:
        email_service = EmailService(db)

        # Send test email using platform configuration
        email_log = email_service.send_raw(
            to_email=request.to_email,
            to_name=None,
            subject="Wizamart Platform - Test Email",
            body_html="""
            <html>
            <body style="font-family: Arial, sans-serif; padding: 20px;">
                <h2 style="color: #6b46c1;">Test Email from Wizamart</h2>
                <p>This is a test email to verify your platform email configuration.</p>
                <p>If you received this email, your email settings are working correctly!</p>
                <hr style="border: none; border-top: 1px solid #e5e7eb; margin: 20px 0;">
                <p style="color: #6b7280; font-size: 12px;">
                    Provider: {provider}<br>
                    From: {from_email}
                </p>
            </body>
            </html>
            """.format(
                provider=app_settings.email_provider,
                from_email=app_settings.email_from_address,
            ),
            body_text=f"Test email from Wizamart platform.\n\nProvider: {app_settings.email_provider}\nFrom: {app_settings.email_from_address}",
            is_platform_email=True,
        )

        # Check if email was actually sent (send_raw returns EmailLog, not boolean)
        if email_log.status == "sent":
            # Log action
            admin_audit_service.log_action(
                db=db,
                admin_user_id=current_admin.id,
                action="send_test_email",
                target_type="email",
                target_id=request.to_email,
                details={"provider": app_settings.email_provider},
            )
            db.commit()

            return TestEmailResponse(
                success=True,
                message=f"Test email sent to {request.to_email}",
            )
        else:
            return TestEmailResponse(
                success=False,
                message=email_log.error_message or "Failed to send test email. Check server logs for details.",
            )

    except Exception as e:
        logger.error(f"Failed to send test email: {e}")
        return TestEmailResponse(
            success=False,
            message=f"Error sending test email: {str(e)}",
        )