import html
import math
from datetime import datetime
from urllib.parse import quote, urlencode

from fastapi import APIRouter, Depends, HTTPException, Query, Request
from fastapi.responses import HTMLResponse, PlainTextResponse

from app.auth import require_user
from app.db.apps import (
    count_deployments,
    get_deployment,
    get_deployment_filter_options,
    get_deployment_stats,
    get_deployments,
)
from app.templates.layout import page

router = APIRouter()

SUCCESS_STATUSES = {"ok", "success", "succeeded", "done", "deployed", "completed"}
RUNNING_STATUSES = {"running", "pending", "queued", "in_progress", "starting"}
FAILED_STATUSES = {"failed", "failure", "error", "cancelled", "canceled"}
DEFAULT_PAGE_SIZE = 20


def normalize_status(status: str | None) -> str:
    return (status or "").strip().lower()


def is_running(status: str | None) -> bool:
    return normalize_status(status) in RUNNING_STATUSES


def is_failed(status: str | None) -> bool:
    return normalize_status(status) in FAILED_STATUSES


def render_status_pill(status: str | None) -> str:
    status_value = status or ""
    normalized = normalize_status(status)

    if normalized in SUCCESS_STATUSES:
        class_name = "pill pill-success"
    elif normalized in RUNNING_STATUSES:
        class_name = "pill pill-warning"
    elif normalized in FAILED_STATUSES:
        class_name = "pill pill-danger"
    else:
        class_name = "pill pill-muted"

    labels = {
        "running": "běží",
        "pending": "čeká",
        "queued": "ve frontě",
        "in_progress": "probíhá",
        "starting": "startuje",
        "success": "úspěšné",
        "ok": "úspěšné",
        "succeeded": "úspěšné",
        "done": "hotovo",
        "deployed": "nasazeno",
        "completed": "dokončeno",
        "failed": "selhalo",
        "failure": "selhalo",
        "error": "chyba",
        "cancelled": "zrušeno",
        "canceled": "zrušeno",
    }
    return f'<span class="{class_name}">{html.escape(labels.get(normalized, status_value))}</span>'


def parse_timestamp(value: str | None) -> datetime | None:
    if not value:
        return None

    normalized = value.strip().replace("Z", "+00:00")
    formats = [
        "%Y-%m-%d %H:%M:%S",
        "%Y-%m-%d %H:%M:%S.%f",
        "%Y-%m-%dT%H:%M:%S",
        "%Y-%m-%dT%H:%M:%S.%f",
    ]

    try:
        return datetime.fromisoformat(normalized)
    except ValueError:
        pass

    for fmt in formats:
        try:
            return datetime.strptime(normalized, fmt)
        except ValueError:
            continue

    return None


def calculate_duration(started_at: str | None, finished_at: str | None) -> str:
    if not started_at or not finished_at:
        return ""

    started = parse_timestamp(started_at)
    finished = parse_timestamp(finished_at)
    if not started or not finished:
        return ""

    seconds = int((finished - started).total_seconds())
    if seconds < 0:
        return ""

    minutes, seconds = divmod(seconds, 60)
    hours, minutes = divmod(minutes, 60)

    if hours:
        return f"{hours}h {minutes}m {seconds}s"
    if minutes:
        return f"{minutes}m {seconds}s"
    return f"{seconds}s"


def actor_label(deployment: dict) -> str:
    display_name = deployment.get("triggered_by_display_name") or ""
    username = deployment.get("triggered_by_username") or ""

    if display_name and username:
        return f"{display_name} (@{username})"
    return display_name or username or ""


def render_options(values: list[str], selected: str | None, empty_label: str) -> str:
    options = [f'<option value="">{html.escape(empty_label)}</option>']
    for value in values:
        selected_attr = " selected" if selected == value else ""
        options.append(f'<option value="{html.escape(value)}"{selected_attr}>{html.escape(value)}</option>')
    return "".join(options)


def pagination_url(page_number: int, status: str, app_id: str, source: str) -> str:
    params = {"page": page_number}
    if status:
        params["status"] = status
    if app_id:
        params["app_id"] = app_id
    if source:
        params["source"] = source
    return f"/portal/deployments?{urlencode(params)}"


@router.get("/deployments", response_class=HTMLResponse)
async def deployments_page(
    request: Request,
    status: str = Query(""),
    app_id: str = Query(""),
    source: str = Query(""),
    page_number: int = Query(1, alias="page", ge=1),
    user=Depends(require_user),
):
    selected_status = status.strip()
    selected_app = app_id.strip()
    selected_source = source.strip()
    offset = (page_number - 1) * DEFAULT_PAGE_SIZE
    total_deployments = count_deployments(
        status=selected_status or None,
        app_id=selected_app or None,
        source=selected_source or None,
    )
    total_pages = max(1, math.ceil(total_deployments / DEFAULT_PAGE_SIZE))
    if page_number > total_pages:
        page_number = total_pages
        offset = (page_number - 1) * DEFAULT_PAGE_SIZE

    deployments = get_deployments(
        limit=DEFAULT_PAGE_SIZE,
        offset=offset,
        status=selected_status or None,
        app_id=selected_app or None,
        source=selected_source or None,
    )
    stats = get_deployment_stats()
    options = get_deployment_filter_options()
    refresh = ""

    rows = ""
    for deployment in deployments:
        deployment_id = html.escape(str(deployment.get("id", "")))
        raw_app_id = deployment.get("app_id", "") or ""
        escaped_app_id = html.escape(raw_app_id)
        app_url_id = quote(raw_app_id, safe="")
        kind = html.escape(deployment.get("kind", "") or "")
        status_pill = render_status_pill(deployment.get("status"))
        started_at = html.escape(deployment.get("started_at", "") or "")
        finished_at = html.escape(deployment.get("finished_at", "") or "")
        source_label = html.escape(deployment.get("trigger_source", "") or "")
        triggered_by = html.escape(actor_label(deployment))
        returncode = deployment.get("returncode")
        returncode_label = "" if returncode is None else html.escape(str(returncode))
        row_class = ' class="running-row"' if is_running(deployment.get("status")) else ""

        rows += f"""
        <tr{row_class}>
            <td>
                <strong>#{deployment_id}</strong><br>
                <span class="muted">{started_at}</span>
            </td>
            <td><a href="/portal/apps/{app_url_id}">{escaped_app_id}</a></td>
            <td>{kind}</td>
            <td>{status_pill}</td>
            <td>{source_label}</td>
            <td>{triggered_by}</td>
            <td>{returncode_label}</td>
            <td>{finished_at}</td>
            <td class="actions-cell">
                <a class="btn" href="/portal/deployments/{deployment_id}">Detail</a>
            </td>
        </tr>
        """

    if not rows:
        rows = '<tr><td colspan="9">Zatím nejsou evidovaná žádná nasazení.</td></tr>'

    status_values = ["running", "success", "failed"]
    status_options = render_options(status_values, selected_status, "Všechny statusy")
    app_options = render_options(options["apps"], selected_app, "Všechny aplikace")
    source_options = render_options(options["sources"], selected_source, "Všechny zdroje")
    first_item = offset + 1 if total_deployments else 0
    last_item = min(offset + len(deployments), total_deployments)
    previous_disabled = " disabled" if page_number <= 1 else ""
    next_disabled = " disabled" if page_number >= total_pages else ""
    previous_href = pagination_url(max(1, page_number - 1), selected_status, selected_app, selected_source)
    next_href = pagination_url(min(total_pages, page_number + 1), selected_status, selected_app, selected_source)
    pagination = f"""
        <div class="pagination">
            <span>Zobrazeno {first_item}-{last_item} z {total_deployments}</span>
            <div class="pagination-actions">
                <a class="btn btn-secondary{previous_disabled}" href="{previous_href}" aria-disabled="{str(page_number <= 1).lower()}">Předchozí</a>
                <span class="page-indicator">Strana {page_number} / {total_pages}</span>
                <a class="btn btn-secondary{next_disabled}" href="{next_href}" aria-disabled="{str(page_number >= total_pages).lower()}">Další</a>
            </div>
        </div>
    """

    return page(
        "Nasazení",
        f"""
        {refresh}
        <div class="card">
            <h2>Historie nasazení</h2>
            <p class="muted">Přehled posledních běhů nasazení a jejich výsledků.</p>
            <a class="btn" href="/portal/operations">&larr; Zpět na přehled</a>
        </div>

        <div class="stats-grid">
            <div class="stat-card stat-total"><span>Celkem nasazení</span><strong>{stats.get("total") or 0}</strong></div>
            <div class="stat-card stat-danger"><span>Selhaná nasazení</span><strong>{stats.get("failed") or 0}</strong></div>
            <div class="stat-card stat-warning"><span>Běžící nasazení</span><strong>{stats.get("running") or 0}</strong></div>
            <div class="stat-card stat-success"><span>Úspěšnost</span><strong>{stats.get("success_rate") or 0}%</strong></div>
        </div>

        <div class="card">
            <h2>Filtry</h2>
            <form method="get" action="/portal/deployments" class="filter-form">
                <select name="status">{status_options}</select>
                <select name="app_id">{app_options}</select>
                <select name="source">{source_options}</select>
                <input type="hidden" name="page" value="1">
                <button type="submit">Filtrovat</button>
                <a class="btn btn-secondary" href="/portal/deployments">Reset</a>
            </form>
        </div>

        <div class="card">
            <h2>Nasazení</h2>
            {pagination}
            <table>
                <tr>
                    <th>ID</th>
                    <th>Aplikace</th>
                    <th>Typ</th>
                    <th>Status</th>
                    <th>Zdroj</th>
                    <th>Spustil</th>
                    <th>Kód</th>
                    <th>Dokončeno</th>
                    <th>Akce</th>
                </tr>
                {rows}
            </table>
            {pagination}
        </div>
        """,
        user=user,
    )


@router.get("/deployments/{deployment_id}/logs/raw", response_class=PlainTextResponse)
async def deployment_raw_logs(
    deployment_id: int,
    request: Request,
    user=Depends(require_user),
):
    deployment = get_deployment(deployment_id)
    if not deployment:
        raise HTTPException(status_code=404, detail="Deployment not found")

    stdout = deployment.get("stdout", "") or ""
    stderr = deployment.get("stderr", "") or ""
    return PlainTextResponse(f"--- stdout ---\n{stdout}\n\n--- stderr ---\n{stderr}")


@router.get("/deployments/{deployment_id}", response_class=HTMLResponse)
async def deployment_detail_page(
    deployment_id: int,
    request: Request,
    user=Depends(require_user),
):
    deployment = get_deployment(deployment_id)

    if not deployment:
        raise HTTPException(status_code=404, detail="Deployment not found")

    title = f"Nasazení #{html.escape(str(deployment.get('id', deployment_id)))}"
    raw_app_id = deployment.get("app_id", "") or ""
    app_id = html.escape(raw_app_id)
    app_url_id = quote(raw_app_id, safe="")
    kind = html.escape(deployment.get("kind", "") or "")
    status = render_status_pill(deployment.get("status"))
    started_at = html.escape(deployment.get("started_at", "") or "")
    finished_at = html.escape(deployment.get("finished_at", "") or "")
    duration = html.escape(calculate_duration(deployment.get("started_at"), deployment.get("finished_at")))
    trigger_source = html.escape(deployment.get("trigger_source", "") or "")
    triggered_by = html.escape(actor_label(deployment))
    commit_author = html.escape(deployment.get("commit_author", "") or "")
    pusher = html.escape(deployment.get("pusher", "") or "")
    returncode = deployment.get("returncode")
    returncode_label = "" if returncode is None else html.escape(str(returncode))
    stdout = html.escape(deployment.get("stdout", "") or "")
    stderr = html.escape(deployment.get("stderr", "") or "")
    refresh = ""
    failed_notice = (
        f'<div class="alert alert-danger">Deployment selhal. Návratový kód: {returncode_label}</div>'
        if is_failed(deployment.get("status"))
        else ""
    )

    return page(
        title,
        f"""
        {refresh}
        <div class="card">
            <h2>{title}</h2>
            <p class="muted">Detail běhu nasazení včetně oddělených výstupů stdout a stderr.</p>
            {failed_notice}
            <p>
                <a class="btn" href="/portal/deployments">&larr; Zpět na nasazení</a>
                <a class="btn btn-secondary" href="/portal/apps/{app_url_id}">Detail služby</a>
                <a class="btn btn-secondary" href="/portal/deployments/{html.escape(str(deployment_id))}/logs/raw">Surové logy</a>
            </p>
        </div>

        <div class="card">
            <h2>Souhrn</h2>
            <table>
                <tr><th>Služba</th><td><a href="/portal/apps/{app_url_id}">{app_id}</a></td></tr>
                <tr><th>Typ</th><td>{kind}</td></tr>
                <tr><th>Status</th><td>{status}</td></tr>
                <tr><th>Zdroj spuštění</th><td>{trigger_source}</td></tr>
                <tr><th>Spustil</th><td>{triggered_by}</td></tr>
                <tr><th>Commit author</th><td>{commit_author}</td></tr>
                <tr><th>Pusher</th><td>{pusher}</td></tr>
                <tr><th>Spuštěno</th><td>{started_at}</td></tr>
                <tr><th>Dokončeno</th><td>{finished_at}</td></tr>
                <tr><th>Duration</th><td>{duration}</td></tr>
                <tr><th>Návratový kód</th><td>{returncode_label}</td></tr>
            </table>
        </div>

        <div class="grid">
            <div class="card">
                <h2>stdout</h2>
                <pre class="log-viewer log-stdout">{stdout}</pre>
            </div>
            <div class="card failed-log">
                <h2>stderr</h2>
                <pre class="log-viewer log-stderr">{stderr}</pre>
            </div>
        </div>
        """,
        user=user,
    )