"""Change History: reverse-chronological feed of recently modified items."""

from fastapi import APIRouter, Request, Depends
from fastapi.templating import Jinja2Templates
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import text
from typing import Optional
from datetime import datetime, timezone

from core.database import get_db
from core.sidebar import get_sidebar_data

router = APIRouter(prefix="/history", tags=["history"])
templates = Jinja2Templates(directory="templates")

# Entity configs: (table, label_column, type_label, url_prefix)
HISTORY_ENTITIES = [
    ("domains", "name", "Domain", "/domains"),
    ("areas", "name", "Area", "/areas"),
    ("projects", "name", "Project", "/projects"),
    ("tasks", "title", "Task", "/tasks"),
    ("notes", "title", "Note", "/notes"),
    ("contacts", "first_name", "Contact", "/contacts"),
    ("meetings", "title", "Meeting", "/meetings"),
    ("decisions", "title", "Decision", "/decisions"),
    ("lists", "name", "List", "/lists"),
    ("appointments", "title", "Appointment", "/appointments"),
    ("links", "label", "Link", "/links"),
    ("files", "original_filename", "File", "/files"),
    ("capture", "content", "Capture", "/capture"),
]


@router.get("/")
async def history_view(
    request: Request,
    entity_type: Optional[str] = None,
    db: AsyncSession = Depends(get_db),
):
    sidebar = await get_sidebar_data(db)

    all_items = []

    for table, label_col, type_label, url_prefix in HISTORY_ENTITIES:
        if entity_type and entity_type != table:
            continue

        try:
            result = await db.execute(text(f"""
                SELECT id, {label_col} as label, updated_at, created_at
                FROM {table}
                WHERE is_deleted = false
                ORDER BY updated_at DESC
                LIMIT 20
            """))
            for r in result:
                row = dict(r._mapping)
                # Determine action
                action = "created"
                if row["updated_at"] and row["created_at"]:
                    diff = abs((row["updated_at"] - row["created_at"]).total_seconds())
                    if diff > 1:
                        action = "modified"

                all_items.append({
                    "type": table,
                    "type_label": type_label,
                    "id": str(row["id"]),
                    "label": str(row["label"] or "Untitled")[:80],
                    "url": f"{url_prefix}/{row['id']}",
                    "updated_at": row["updated_at"],
                    "action": action,
                })
        except Exception:
            continue

    # Sort by updated_at descending, take top 50
    all_items.sort(key=lambda x: x["updated_at"] or datetime.min.replace(tzinfo=timezone.utc), reverse=True)
    all_items = all_items[:50]

    # Build entity type options for filter
    type_options = [{"value": t[0], "label": t[2]} for t in HISTORY_ENTITIES]

    return templates.TemplateResponse("history.html", {
        "request": request, "sidebar": sidebar,
        "items": all_items,
        "type_options": type_options,
        "current_type": entity_type or "",
        "page_title": "Change History", "active_nav": "history",
    })