from pydantic import BaseModel
from typing import Optional, List
from datetime import datetime
from enum import Enum


class TaskTypeEnum(str, Enum):
    ISSUE = "issue"
    MAINTENANCE = "maintenance"
    RESEARCH = "research"
    REVIEW = "review"
    STORY = "story"
    TEST = "test"
    RESOLUTION = "resolution"
    TASK = "task"


class TaskStatusEnum(str, Enum):
    OPEN = "open"
    PENDING = "pending"
    PROGRESSING = "progressing"
    CLOSED = "closed"


class TaskPriorityEnum(str, Enum):
    LOW = "low"
    MEDIUM = "medium"
    HIGH = "high"
    CRITICAL = "critical"


# Task schemas
class TaskBase(BaseModel):
    title: str
    description: Optional[str] = None
    task_type: TaskTypeEnum = TaskTypeEnum.TASK
    task_subtype: Optional[str] = None
    priority: TaskPriorityEnum = TaskPriorityEnum.MEDIUM
    tags: Optional[str] = None
    estimated_effort: Optional[int] = None
    estimated_working_time: Optional[str] = None


class TaskCreate(TaskBase):
    project_id: Optional[int] = None
    milestone_id: Optional[int] = None
    reporter_id: Optional[int] = None
    assignee_id: Optional[int] = None
    # Resolution specific
    resolution_summary: Optional[str] = None
    positions: Optional[str] = None
    pending_matters: Optional[str] = None


class TaskUpdate(BaseModel):
    title: Optional[str] = None
    description: Optional[str] = None
    task_type: Optional[TaskTypeEnum] = None
    task_subtype: Optional[str] = None
    status: Optional[TaskStatusEnum] = None
    priority: Optional[TaskPriorityEnum] = None
    assignee_id: Optional[int] = None
    tags: Optional[str] = None
    estimated_effort: Optional[int] = None
    # Resolution specific
    resolution_summary: Optional[str] = None
    positions: Optional[str] = None
    pending_matters: Optional[str] = None


class TaskResponse(TaskBase):
    id: int
    status: TaskStatusEnum
    task_code: Optional[str] = None
    project_id: int
    milestone_id: int
    reporter_id: int
    assignee_id: Optional[int] = None
    resolution_summary: Optional[str] = None
    positions: Optional[str] = None
    pending_matters: Optional[str] = None
    created_at: datetime
    updated_at: Optional[datetime] = None
    
    class Config:
        from_attributes = True


# Comment schemas
class CommentBase(BaseModel):
    content: str


class CommentCreate(CommentBase):
    task_id: int
    author_id: int


class CommentUpdate(BaseModel):
    content: Optional[str] = None


class CommentResponse(CommentBase):
    id: int
    task_id: int
    author_id: int
    created_at: datetime
    updated_at: Optional[datetime] = None
    
    class Config:
        from_attributes = True


# Project schemas
class ProjectBase(BaseModel):
    name: str
    owner_name: Optional[str] = None
    description: Optional[str] = None
    sub_projects: Optional[list[str]] = None
    related_projects: Optional[list[str]] = None


class ProjectCreate(ProjectBase):
    owner_id: int


class ProjectUpdate(BaseModel):
    description: Optional[str] = None
    owner_name: Optional[str] = None
    sub_projects: Optional[list[str]] = None
    related_projects: Optional[list[str]] = None


class ProjectResponse(BaseModel):
    id: int
    name: str
    owner_name: Optional[str] = None
    project_code: Optional[str] = None
    description: Optional[str] = None
    sub_projects: Optional[list[str]] = None
    related_projects: Optional[list[str]] = None
    owner_id: int
    created_at: datetime


# User schemas
class UserBase(BaseModel):
    username: str
    email: str
    full_name: Optional[str] = None


class UserCreate(UserBase):
    password: Optional[str] = None
    is_admin: bool = False


class UserResponse(UserBase):
    id: int
    is_active: bool
    is_admin: bool
    created_at: datetime
    
    class Config:
        from_attributes = True


# Project Member schemas
class ProjectMemberBase(BaseModel):
    user_id: int
    role: str = "dev"


class ProjectMemberCreate(ProjectMemberBase):
    pass


class ProjectMemberResponse(BaseModel):
    id: int
    user_id: int
    project_id: int
    role: str = "dev"
    
    class Config:
        from_attributes = True


# Milestone schemas
class MilestoneBase(BaseModel):
    title: str
    description: Optional[str] = None
    status: Optional[str] = "open"
    due_date: Optional[datetime] = None
    planned_release_date: Optional[datetime] = None
    depend_on_milestones: Optional[List[str]] = None
    depend_on_tasks: Optional[List[int]] = None


class MilestoneCreate(MilestoneBase):
    project_id: Optional[int] = None
    pass


class MilestoneUpdate(BaseModel):
    title: Optional[str] = None
    description: Optional[str] = None
    status: Optional[str] = None
    due_date: Optional[datetime] = None
    planned_release_date: Optional[datetime] = None
    depend_on_milestones: Optional[List[str]] = None
    depend_on_tasks: Optional[List[int]] = None


class MilestoneResponse(MilestoneBase):
    id: int
    project_id: int
    created_at: datetime
    updated_at: Optional[datetime] = None

    class Config:
        from_attributes = True


# Paginated response
from typing import Generic, TypeVar
T = TypeVar("T")

class PaginatedResponse(BaseModel, Generic[T]):
    items: List[T]
    total: int
    page: int
    page_size: int
    total_pages: int