from typing import List, Optional

from fastapi import APIRouter, Depends, HTTPException

from app.api.deps import get_training_repository
from app.core.database.repository import TrainingRepository
from app.core.dto.training import ExerciseNameDTO
from app.core.metrics import Record, summarize
from app.schemas.exercises import (
    ExerciseProgressResponse,
    RecordResponse,
    SessionMetricsResponse,
    SessionRowResponse,
)

router = APIRouter()


def record_response(record: Optional[Record]) -> Optional[RecordResponse]:
    return RecordResponse(value=record.value, date=record.date) if record else None


@router.get("/", response_model=List[ExerciseNameDTO])
async def list_exercise_names(
    repository: TrainingRepository = Depends(get_training_repository),
):
    """Distinct exercise names with the number of times each was done."""
    return await repository.list_exercise_names()


@router.get("/progress/", response_model=ExerciseProgressResponse)
async def exercise_progress(
    name: str,
    repository: TrainingRepository = Depends(get_training_repository),
):
    """The whole history of the exercise with progress metrics.

    The name is matched exactly, but case-insensitively: what was typed may differ in case.
    """
    names_by_casefold = {
        item.name.casefold(): item.name
        for item in await repository.list_exercise_names()
    }
    exact_name = names_by_casefold.get(name.strip().casefold())
    if exact_name is None:
        raise HTTPException(status_code=404, detail="Exercise not found")

    progress = summarize(await repository.exercise_history(exact_name))
    return ExerciseProgressResponse(
        name=exact_name,
        weighted=progress.weighted,
        max_weight=progress.max_weight,
        best_primary=record_response(progress.best_primary),
        best_secondary=record_response(progress.best_secondary),
        first_primary=progress.first_primary,
        last_primary=progress.last_primary,
        primary_change=progress.primary_change,
        primary_change_percent=progress.primary_change_percent,
        rows=[
            SessionRowResponse(
                date=row.session.date,
                trainer=row.session.trainer,
                splitted_weight=row.session.splitted_weight,
                approaches=row.session.approaches,
                metrics=SessionMetricsResponse.model_validate(
                    row.metrics, from_attributes=True
                ),
            )
            for row in progress.rows
        ],
    )