from datetime import datetime
from decimal import Decimal
from enum import Enum
from typing import Optional

from pydantic import BaseModel, Field


class AccountType(str, Enum):
    ASSET = "asset"
    LIABILITY = "liability"
    EQUITY = "equity"
    REVENUE = "revenue"
    EXPENSE = "expense"


class JournalEntryFlag(str, Enum):
    """Transaction status flags (Beancount-compatible)

    Beancount only supports two user-facing flags:
    - * (CLEARED): Completed transactions
    - ! (PENDING): Transactions needing attention

    For voided/flagged transactions, use tags instead:
    - Voided: Use "!" flag + #voided tag
    - Flagged: Use "!" flag + #review tag
    """
    CLEARED = "*"      # Fully reconciled/confirmed
    PENDING = "!"      # Not yet confirmed/awaiting approval


class Account(BaseModel):
    id: str
    name: str
    account_type: AccountType
    description: Optional[str] = None
    user_id: Optional[str] = None  # For user-specific accounts
    created_at: datetime
    is_active: bool = True  # Soft delete flag
    is_virtual: bool = False  # Virtual parent account (metadata-only, not in Beancount)


class CreateAccount(BaseModel):
    name: str
    account_type: AccountType
    description: Optional[str] = None
    user_id: Optional[str] = None
    is_virtual: bool = False  # Set to True to create virtual parent account


class EntryLine(BaseModel):
    id: str
    journal_entry_id: str
    account_id: str
    amount: int  # in satoshis; positive = debit, negative = credit
    description: Optional[str] = None
    metadata: dict = {}  # Stores currency info: fiat_currency, fiat_amount, fiat_rate, etc.


class CreateEntryLine(BaseModel):
    account_id: str
    amount: int  # in satoshis; positive = debit, negative = credit
    description: Optional[str] = None
    metadata: dict = {}  # Stores currency info


class JournalEntry(BaseModel):
    id: str
    description: str
    entry_date: datetime
    created_by: str  # wallet ID of user who created it
    created_at: datetime
    reference: Optional[str] = None  # Invoice ID or reference number
    lines: list[EntryLine] = []
    flag: JournalEntryFlag = JournalEntryFlag.CLEARED  # Transaction status
    meta: dict = {}  # Metadata: source, tags, links, notes, etc.


class CreateJournalEntry(BaseModel):
    description: str
    entry_date: Optional[datetime] = None
    reference: Optional[str] = None
    lines: list[CreateEntryLine]
    flag: JournalEntryFlag = JournalEntryFlag.CLEARED
    meta: dict = {}


class UserBalance(BaseModel):
    user_id: str
    balance: int  # positive = castle owes user, negative = user owes castle
    accounts: list[Account] = []
    fiat_balances: dict[str, Decimal] = {}  # e.g. {"EUR": Decimal("250.0"), "USD": Decimal("100.0")}


class ExpenseEntry(BaseModel):
    """Helper model for creating expense entries"""

    description: str
    amount: Decimal  # Amount in the specified currency (or satoshis if currency is None)
    expense_account: str  # account name or ID
    is_equity: bool = False  # True = equity contribution, False = liability (castle owes user)
    user_wallet: str
    reference: Optional[str] = None
    currency: Optional[str] = None  # If None, amount is in satoshis. Otherwise, fiat currency code (EUR, USD, etc.)
    entry_date: Optional[datetime] = None  # Date of the expense transaction


class ReceivableEntry(BaseModel):
    """Helper model for creating accounts receivable entries"""

    description: str
    amount: Decimal  # Amount in the specified currency (or satoshis if currency is None)
    revenue_account: str  # account name or ID
    user_id: str  # The user_id (not wallet_id) of the user who owes the castle
    reference: Optional[str] = None
    currency: Optional[str] = None  # If None, amount is in satoshis. Otherwise, fiat currency code


class RevenueEntry(BaseModel):
    """Helper model for creating revenue entries"""

    description: str
    amount: Decimal  # Amount in the specified currency (or satoshis if currency is None)
    revenue_account: str
    payment_method_account: str  # e.g., "Cash", "Bank", "Lightning"
    reference: Optional[str] = None
    currency: Optional[str] = None  # If None, amount is in satoshis. Otherwise, fiat currency code


class CastleSettings(BaseModel):
    """Settings for the Castle extension"""

    castle_wallet_id: Optional[str] = None  # The wallet ID that represents the Castle

    # Fava/Beancount integration - ALL accounting is done via Fava
    fava_url: str = "http://localhost:3333"  # Base URL of Fava server
    fava_ledger_slug: str = "castle-ledger"  # Ledger identifier in Fava URL
    fava_timeout: float = 10.0  # Request timeout in seconds

    updated_at: datetime = Field(default_factory=lambda: datetime.now())

    @classmethod
    def is_admin_only(cls) -> bool:
        return True


class UserCastleSettings(CastleSettings):
    """User-specific settings (stored with user_id)"""

    id: str


class UserWalletSettings(BaseModel):
    """Per-user wallet settings"""

    user_wallet_id: Optional[str] = None  # The wallet ID for this specific user
    updated_at: datetime = Field(default_factory=lambda: datetime.now())


class StoredUserWalletSettings(UserWalletSettings):
    """Stored user wallet settings with user ID"""

    id: str  # user_id


class ManualPaymentRequest(BaseModel):
    """Manual payment request from user to castle"""

    id: str
    user_id: str
    amount: int  # in satoshis
    description: str
    status: str = "pending"  # pending, approved, rejected
    created_at: datetime
    reviewed_at: Optional[datetime] = None
    reviewed_by: Optional[str] = None  # user_id of castle admin who reviewed
    journal_entry_id: Optional[str] = None  # set when approved


class CreateManualPaymentRequest(BaseModel):
    """Create a manual payment request"""

    amount: int
    description: str


class GeneratePaymentInvoice(BaseModel):
    """Generate payment invoice request"""

    amount: int
    user_id: Optional[str] = None  # For admin-generated settlement invoices


class RecordPayment(BaseModel):
    """Record a payment"""

    payment_hash: str


class SettleReceivable(BaseModel):
    """Manually settle a receivable (user pays castle in person)"""

    user_id: str
    amount: Decimal  # Amount in the specified currency (or satoshis if currency is None)
    payment_method: str  # "cash", "bank_transfer", "check", "lightning", "btc_onchain", "other"
    description: str  # Description of the payment
    reference: Optional[str] = None  # Optional reference (receipt number, transaction ID, etc.)
    currency: Optional[str] = None  # If None, amount is in satoshis. Otherwise, fiat currency code (EUR, USD, etc.)
    amount_sats: Optional[int] = None  # Equivalent amount in sats (for reference/conversion tracking)
    payment_hash: Optional[str] = None  # For lightning payments
    txid: Optional[str] = None  # For on-chain Bitcoin transactions


class PayUser(BaseModel):
    """Pay a user (castle pays user for expense/liability)"""

    user_id: str
    amount: Decimal  # Amount in the specified currency (or satoshis if currency is None)
    payment_method: str  # "cash", "bank_transfer", "check", "lightning", "btc_onchain", "other"
    description: Optional[str] = None  # Description of the payment
    reference: Optional[str] = None  # Optional reference (receipt number, transaction ID, etc.)
    currency: Optional[str] = None  # If None, amount is in satoshis. Otherwise, fiat currency code (EUR, USD, etc.)
    amount_sats: Optional[int] = None  # Equivalent amount in sats (for reference/conversion tracking)
    payment_hash: Optional[str] = None  # For lightning payments
    txid: Optional[str] = None  # For on-chain Bitcoin transactions


class AssertionStatus(str, Enum):
    """Status of a balance assertion"""
    PENDING = "pending"    # Not yet checked
    PASSED = "passed"      # Assertion passed (balance matches)
    FAILED = "failed"      # Assertion failed (balance mismatch)


class BalanceAssertion(BaseModel):
    """Assert expected balance at a specific date for reconciliation"""
    id: str
    date: datetime
    account_id: str
    expected_balance_sats: int  # Expected balance in satoshis
    expected_balance_fiat: Optional[Decimal] = None  # Optional fiat balance
    fiat_currency: Optional[str] = None  # Currency for fiat balance (EUR, USD, etc.)
    tolerance_sats: int = 0  # Allow +/- this much difference in sats
    tolerance_fiat: Decimal = Decimal("0")  # Allow +/- this much difference in fiat
    checked_balance_sats: Optional[int] = None  # Actual balance found
    checked_balance_fiat: Optional[Decimal] = None  # Actual fiat balance found
    difference_sats: Optional[int] = None  # Difference in sats
    difference_fiat: Optional[Decimal] = None  # Difference in fiat
    status: AssertionStatus = AssertionStatus.PENDING
    created_by: str
    created_at: datetime
    checked_at: Optional[datetime] = None


class CreateBalanceAssertion(BaseModel):
    """Create a balance assertion"""
    account_id: str
    date: Optional[datetime] = None  # If None, use current time
    expected_balance_sats: int
    expected_balance_fiat: Optional[Decimal] = None
    fiat_currency: Optional[str] = None
    tolerance_sats: int = 0
    tolerance_fiat: Decimal = Decimal("0")


class UserEquityStatus(BaseModel):
    """Tracks user's equity eligibility and status"""
    user_id: str  # User's wallet ID
    is_equity_eligible: bool  # Can user convert expenses to equity?
    equity_account_name: Optional[str] = None  # e.g., "Equity:Alice"
    notes: Optional[str] = None  # Admin notes
    granted_by: str  # Admin who granted eligibility
    granted_at: datetime
    revoked_at: Optional[datetime] = None  # If eligibility was revoked


class CreateUserEquityStatus(BaseModel):
    """Create or update user equity eligibility"""
    user_id: str
    is_equity_eligible: bool
    equity_account_name: Optional[str] = None  # Auto-generated as "Equity:User-{user_id}" if not provided
    notes: Optional[str] = None


class UserInfo(BaseModel):
    """User information including equity eligibility"""
    user_id: str
    is_equity_eligible: bool
    equity_account_name: Optional[str] = None


class PermissionType(str, Enum):
    """Types of permissions for account access"""
    READ = "read"  # Can view account and its balance
    SUBMIT_EXPENSE = "submit_expense"  # Can submit expenses to this account
    MANAGE = "manage"  # Can modify account (admin level)


class AccountPermission(BaseModel):
    """Defines which accounts a user can access"""
    id: str  # Unique permission ID
    user_id: str  # User's wallet ID (from invoice key)
    account_id: str  # Account ID from accounts table
    permission_type: PermissionType
    granted_by: str  # Admin user ID who granted permission
    granted_at: datetime
    expires_at: Optional[datetime] = None  # Optional expiration
    notes: Optional[str] = None  # Admin notes about this permission


class CreateAccountPermission(BaseModel):
    """Create account permission"""
    user_id: str
    account_id: str
    permission_type: PermissionType
    expires_at: Optional[datetime] = None
    notes: Optional[str] = None


class BulkGrantPermission(BaseModel):
    """Bulk grant same permission to multiple users"""
    user_ids: list[str]  # List of user IDs to grant permission to
    account_id: str  # Account to grant permission on
    permission_type: PermissionType  # Type of permission to grant
    expires_at: Optional[datetime] = None  # Optional expiration
    notes: Optional[str] = None  # Notes for all permissions


class BulkGrantResult(BaseModel):
    """Result of bulk grant operation"""
    granted: list[AccountPermission]  # Successfully granted permissions
    failed: list[dict]  # Failed grants with errors
    total: int  # Total attempted
    success_count: int  # Number of successful grants
    failure_count: int  # Number of failed grants


class AccountWithPermissions(BaseModel):
    """Account with user-specific permission metadata"""
    id: str
    name: str
    account_type: AccountType
    description: Optional[str] = None
    user_id: Optional[str] = None
    created_at: datetime
    is_active: bool = True  # Soft delete flag
    is_virtual: bool = False  # Virtual parent account (metadata-only)
    # Only included when filter_by_user=true
    user_permissions: Optional[list[PermissionType]] = None
    inherited_from: Optional[str] = None  # Parent account ID if inherited
    # Hierarchical structure
    parent_account: Optional[str] = None  # Parent account name
    level: Optional[int] = None  # Depth in hierarchy (0 = top level)
    has_children: Optional[bool] = None  # Whether this account has sub-accounts


# ===== ROLE-BASED ACCESS CONTROL (RBAC) MODELS =====


class Role(BaseModel):
    """Role definition for RBAC system"""
    id: str
    name: str  # Display name (e.g., "Employee", "Contractor")
    description: Optional[str] = None
    is_default: bool = False  # Auto-assign this role to new users
    created_by: str  # User ID who created the role
    created_at: datetime


class CreateRole(BaseModel):
    """Create a new role"""
    name: str
    description: Optional[str] = None
    is_default: bool = False


class UpdateRole(BaseModel):
    """Update an existing role"""
    name: Optional[str] = None
    description: Optional[str] = None
    is_default: Optional[bool] = None


class RolePermission(BaseModel):
    """Permission granted to a role for a specific account"""
    id: str
    role_id: str
    account_id: str
    permission_type: PermissionType
    notes: Optional[str] = None
    created_at: datetime


class CreateRolePermission(BaseModel):
    """Create a permission for a role"""
    role_id: str
    account_id: str
    permission_type: PermissionType
    notes: Optional[str] = None


class UserRole(BaseModel):
    """Assignment of a user to a role"""
    id: str
    user_id: str  # User's wallet ID
    role_id: str
    granted_by: str  # Admin who assigned the role
    granted_at: datetime
    expires_at: Optional[datetime] = None
    notes: Optional[str] = None


class AssignUserRole(BaseModel):
    """Assign a user to a role"""
    user_id: str
    role_id: str
    expires_at: Optional[datetime] = None
    notes: Optional[str] = None


class RoleWithPermissions(BaseModel):
    """Role with its associated permissions and user count"""
    role: Role
    permissions: list[RolePermission]
    user_count: int  # Number of users assigned to this role


class UserWithRoles(BaseModel):
    """User information with their assigned roles"""
    user_id: str
    roles: list[Role]
    direct_permissions: list[AccountPermission]  # Individual permissions not from roles