import uvicorn
from fastapi import FastAPI, HTTPException, Query
from fastapi.openapi.docs import get_swagger_ui_html
from fastapi.staticfiles import StaticFiles
from fastapi.responses import HTMLResponse
from pydantic import BaseModel
from typing import Literal
from datetime import date


# ── Models ────────────────────────────────────────────────────────────────────

class Transaction(BaseModel):
    transaction_id: str
    date: date
    account: str
    amount: float
    status: Literal["Matched", "Unmatched", "Pending"]
    flag: Literal["None", "Duplicate", "Threshold Breach", "Manual Review"]


class ReconSummary(BaseModel):
    total: int
    matched: int
    unmatched: int
    pending: int
    flagged: int


# ── Sample data ───────────────────────────────────────────────────────────────

TRANSACTIONS: list[Transaction] = [
    Transaction(transaction_id="TXN-001", date=date(2026, 4, 10), account="ACC-9821", amount=12400.00, status="Matched",   flag="None"),
    Transaction(transaction_id="TXN-002", date=date(2026, 4, 11), account="ACC-4473", amount=3750.50,  status="Unmatched", flag="Duplicate"),
    Transaction(transaction_id="TXN-003", date=date(2026, 4, 11), account="ACC-1190", amount=88200.00, status="Unmatched", flag="Threshold Breach"),
    Transaction(transaction_id="TXN-004", date=date(2026, 4, 12), account="ACC-6654", amount=540.00,   status="Matched",   flag="None"),
    Transaction(transaction_id="TXN-005", date=date(2026, 4, 13), account="ACC-3312", amount=21000.00, status="Pending",   flag="Manual Review"),
]


# ── App ───────────────────────────────────────────────────────────────────────

app = FastAPI(
    title="Recon Ranger",
    description="Financial crime reconciliation API — patrol your data landscape for inconsistencies.",
    version="0.1.0",
    docs_url=None,
)
app.mount("/static", StaticFiles(directory="static"), name="static")


# ── Endpoints ─────────────────────────────────────────────────────────────────

@app.get(
    "/api/transactions",
    response_model=list[Transaction],
    summary="List transactions",
    tags=["Transactions"],
)
async def list_transactions(
    status: Literal["Matched", "Unmatched", "Pending"] | None = Query(None, description="Filter by status"),
    flag:   Literal["None", "Duplicate", "Threshold Breach", "Manual Review"] | None = Query(None, description="Filter by flag"),
) -> list[Transaction]:
    """Return all transactions, optionally filtered by status and/or flag."""
    results = TRANSACTIONS
    if status:
        results = [t for t in results if t.status == status]
    if flag:
        results = [t for t in results if t.flag == flag]
    return results


@app.get(
    "/api/transactions/{transaction_id}",
    response_model=Transaction,
    summary="Get a transaction",
    tags=["Transactions"],
)
async def get_transaction(transaction_id: str) -> Transaction:
    """Retrieve a single transaction by ID."""
    for t in TRANSACTIONS:
        if t.transaction_id == transaction_id:
            return t
    raise HTTPException(status_code=404, detail=f"{transaction_id} not found")


@app.post(
    "/api/transactions",
    response_model=Transaction,
    status_code=201,
    summary="Submit a transaction",
    tags=["Transactions"],
)
async def create_transaction(transaction: Transaction) -> Transaction:
    """Submit a new transaction for reconciliation."""
    for t in TRANSACTIONS:
        if t.transaction_id == transaction.transaction_id:
            raise HTTPException(status_code=409, detail=f"{transaction.transaction_id} already exists")
    TRANSACTIONS.append(transaction)
    return transaction


@app.get(
    "/api/summary",
    response_model=ReconSummary,
    summary="Reconciliation summary",
    tags=["Reporting"],
)
async def get_summary() -> ReconSummary:
    """Return aggregate counts across all transactions."""
    return ReconSummary(
        total=len(TRANSACTIONS),
        matched=sum(1 for t in TRANSACTIONS if t.status == "Matched"),
        unmatched=sum(1 for t in TRANSACTIONS if t.status == "Unmatched"),
        pending=sum(1 for t in TRANSACTIONS if t.status == "Pending"),
        flagged=sum(1 for t in TRANSACTIONS if t.flag != "None"),
    )


@app.delete(
    "/api/transactions/{transaction_id}",
    status_code=204,
    summary="Delete a transaction",
    tags=["Transactions"],
)
async def delete_transaction(transaction_id: str) -> None:
    """Remove a transaction by ID."""
    for i, t in enumerate(TRANSACTIONS):
        if t.transaction_id == transaction_id:
            TRANSACTIONS.pop(i)
            return
    raise HTTPException(status_code=404, detail=f"{transaction_id} not found")



@app.get("/api/docs", include_in_schema=False)
async def swagger_ui_dark() -> HTMLResponse:
    base = get_swagger_ui_html(
        openapi_url=app.openapi_url,
        title="Recon Ranger — API Docs",
        swagger_css_url="/static/api/swagger-ui.css",
    )
    html = base.body.decode()

    # Inject dark theme + main site styles
    html = html.replace(
        "</head>",
        (
            '<link rel="stylesheet" href="/static/css/styles.css">\n'
            '<link rel="stylesheet" href="/static/api/swagger-dark.css">\n'
            "<style>.swagger-ui .topbar { display: none; }</style>\n"
            "</head>"
        ),
    )

    # Inject the site nav bar before Swagger's root div
    nav_html = """
<header>
  <nav>
    <div class="menu">
      <div class="logo"><a href="/">Recon Ranger</a></div>
      <ul>
        <li><a href="/">Home</a></li>
        <li><a href="/api/docs">API</a></li>
        <li><a href="mailto:someone@example.com">Contact</a></li>
      </ul>
    </div>
  </nav>
</header>
<div style="padding-top:70px; position:relative; z-index:1">
"""
    html = html.replace("<body>", "<body>" + nav_html)
    html = html.replace("</body>", "</div></body>")

    return HTMLResponse(html)


if __name__ == "__main__":
    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)