"""Authenticated export of entries and daily rows as JSONL or CSV.

Exports stream whole files from DATA_ROOT without mounting that directory.
"""

import csv
import io
from typing import Any

from fastapi import APIRouter, Depends, Request
from fastapi.responses import PlainTextResponse, Response

from app.deps import require_login
from app.fsutil import read_jsonl

router = APIRouter(
    prefix="/api/export",
    tags=["export"],
    dependencies=[Depends(require_login)],
)

CSV_COLUMNS = [
    "id",
    "ts",
    "created_at",
    "updated_at",
    "activity",
    "happened",
    "emotions",
    "intensity",
    "remedy",
    "result",
    "tags",
    "notes",
]


def _jsonl_response(path) -> Response:
    if not path.exists():
        content = ""
    else:
        content = path.read_text(encoding="utf-8")
    return Response(content=content, media_type="application/x-ndjson")


@router.get("/entries.jsonl")
def export_entries_jsonl(request: Request) -> Response:
    """Download entries as newline-delimited JSON."""

    return _jsonl_response(request.app.state.paths.entries)


@router.get("/daily.jsonl")
def export_daily_jsonl(request: Request) -> Response:
    """Download daily rows as newline-delimited JSON."""

    return _jsonl_response(request.app.state.paths.daily)


@router.get("/entries.csv")
def export_entries_csv(request: Request) -> PlainTextResponse:
    """Download entries as CSV with fixed headers."""

    records: list[dict[str, Any]] = read_jsonl(request.app.state.paths.entries)
    buffer = io.StringIO()
    writer = csv.DictWriter(buffer, fieldnames=CSV_COLUMNS, extrasaction="ignore")
    writer.writeheader()
    for record in records:
        row = {key: record.get(key, "") for key in CSV_COLUMNS}
        emotions = record.get("emotions") or []
        tags = record.get("tags") or []
        row["emotions"] = "|".join(str(item) for item in emotions)
        row["tags"] = "|".join(str(item) for item in tags)
        writer.writerow(row)
    return PlainTextResponse(content=buffer.getvalue(), media_type="text/csv")