from datetime import datetime
from typing import List, Optional

try:
    from fastapi import FastAPI, HTTPException
    from pydantic import BaseModel
except ImportError:
    FastAPI = None
    HTTPException = None
    BaseModel = object

from .config import Config
from .queue import migration_queue
from .table_config_repository import TableConfigRepository


# ============================================================================
# FASTAPI
# ============================================================================
class MigrationRequest(BaseModel):
    """Запрос на запуск миграции из API."""
    tables: Optional[List[str]] = None
    send_email: bool = True
    dry_run: Optional[bool] = None
    read_limit: Optional[int] = None
    force_full: bool = False
    run_at: Optional[datetime] = None
    delay_seconds: Optional[int] = None


class ScheduleRequest(BaseModel):
    """Запрос на создание расписания миграции."""
    schedule_type: str
    tables: Optional[List[str]] = None
    send_email: bool = True
    dry_run: Optional[bool] = None
    read_limit: Optional[int] = None
    interval_seconds: Optional[int] = None
    daily_time: Optional[str] = None
    start_at: Optional[datetime] = None
    name: Optional[str] = None
    enabled: bool = True
    catch_up_missed_runs: bool = False
    initial_force_full: bool = False


def create_app():
    """Создание FastAPI приложения."""
    if FastAPI is None:
        return None

    api = FastAPI(title="Syncio Migration API", version="0.1.0")

    @api.on_event("startup")
    def startup_queue():
        if Config.START_API_WORKER:
            migration_queue.start()

    @api.get("/health")
    def health():
        return {"status": "ok"}

    @api.get("/tables")
    def tables():
        from sqlalchemy import create_engine

        config = Config()
        engine = create_engine(config.POSTGRES_CONNECTION_STRING)
        repository = TableConfigRepository(config, engine)
        table_configs = repository.load_configs(seed_defaults=True)
        return [
            {
                "source_table": table.source_table,
                "target_table": table.pg_table,
                "mode": table.mode,
                "life_table": table.life_table,
                "datetime_column": table.datetime_column,
                "sequence_column": table.sequence_column,
                "operation_column": table.operation_column,
                "initial_load_mode": table.initial_load_mode,
                "order_columns": table.incremental_order_columns,
                "timescale": table.timescale,
                "enabled": table.enabled,
            }
            for table in table_configs
        ]

    @api.get("/migrations/status")
    def migration_status():
        return migration_queue.get_status()

    @api.get("/migrations/queue")
    def migration_queue_list():
        return migration_queue.list_jobs()

    @api.get("/migrations/queue/{job_id}")
    def migration_queue_job(job_id: str):
        job = migration_queue.get_job(job_id)
        if not job:
            raise HTTPException(status_code=404, detail="Job not found")
        return job

    @api.get("/migrations/schedules")
    def migration_schedule_list():
        return migration_queue.list_schedules()

    @api.get("/migrations/schedules/{schedule_id}")
    def migration_schedule(schedule_id: str):
        schedule = migration_queue.get_schedule(schedule_id)
        if not schedule:
            raise HTTPException(status_code=404, detail="Schedule not found")
        return schedule

    @api.post("/migrations/run")
    def run_migration(request: MigrationRequest):
        try:
            job = migration_queue.enqueue(
                tables=request.tables,
                send_email=request.send_email,
                dry_run=request.dry_run,
                read_limit=request.read_limit,
                force_full=request.force_full,
                run_at=request.run_at,
                delay_seconds=request.delay_seconds,
            )
        except ValueError as exc:
            raise HTTPException(status_code=422, detail=str(exc))

        return {"status": "queued", "job": job}

    @api.post("/migrations/tables/{table_name}/run")
    def run_table_migration(table_name: str):
        job = migration_queue.enqueue(tables=[table_name], send_email=True)
        return {"status": "queued", "job": job}

    @api.post("/migrations/schedules")
    def create_schedule(request: ScheduleRequest):
        try:
            schedule = migration_queue.create_schedule(
                schedule_type=request.schedule_type,
                tables=request.tables,
                send_email=request.send_email,
                dry_run=request.dry_run,
                read_limit=request.read_limit,
                interval_seconds=request.interval_seconds,
                daily_time=request.daily_time,
                start_at=request.start_at,
                name=request.name,
                enabled=request.enabled,
                catch_up_missed_runs=request.catch_up_missed_runs,
                initial_force_full=request.initial_force_full,
            )
        except ValueError as exc:
            raise HTTPException(status_code=422, detail=str(exc))

        return {"status": "scheduled", "schedule": schedule}

    return api


app = create_app()