import html
import os
from pathlib import Path

from fastapi import APIRouter, Depends, Form, HTTPException, Request
from fastapi.responses import HTMLResponse, RedirectResponse

from app.auth import require_user
from app.db.audit import log_audit_event
from app.db.jobs import create_job
from app.db.scheduled_scripts import (
    create_scheduled_script,
    delete_scheduled_script,
    get_scheduled_script,
    get_scheduled_scripts,
    set_scheduled_script_enabled,
    update_scheduled_script,
)
from app.routes.deployments import render_status_pill
from app.templates.layout import page
from app.tools_repo import TOOLS_REPO_DIR, commit_and_push

router = APIRouter()
MAINTENANCE_DIR = TOOLS_REPO_DIR / "maintenance"
MAX_SCRIPT_BYTES = 100 * 1024
DEFAULT_SCRIPT_CONTENT = """#!/usr/bin/env bash
set -euo pipefail

echo "TODO"
"""
SCHEDULE_TYPES = ("hourly", "daily", "weekly", "monthly")
SCHEDULE_LABELS = {
    "hourly": "každou hodinu",
    "daily": "denně",
    "weekly": "týdně",
    "monthly": "měsíčně",
}


def clean_optional(value: str | None) -> str:
    return (value or "").strip()


def is_admin(user) -> bool:
    return (user.get("role") or "").lower() == "admin"


def render_bool(value) -> str:
    return "Ano" if value else "Ne"


def render_schedule_type(value: str | None) -> str:
    value = value or ""
    return SCHEDULE_LABELS.get(value, html.escape(value))


def render_schedule_options(selected: str) -> str:
    options = []
    for value in SCHEDULE_TYPES:
        selected_attr = " selected" if selected == value else ""
        options.append(f'<option value="{value}"{selected_attr}>{render_schedule_type(value)}</option>')
    return "".join(options)


def render_enabled_pill(value) -> str:
    if value:
        return '<span class="pill pill-success">zapnuto</span>'
    return '<span class="pill pill-muted">vypnuto</span>'


def render_running_pill(value) -> str:
    if value:
        return '<span class="pill pill-warning">běží</span>'
    return '<span class="pill pill-muted">neběží</span>'


def validate_script_name(value: str) -> str:
    script_name = clean_optional(value)
    if not script_name:
        raise HTTPException(status_code=400, detail="Název skriptu je povinný")
    if not script_name.endswith(".sh"):
        raise HTTPException(status_code=400, detail="Název skriptu musí končit .sh")
    if "/" in script_name or "\\" in script_name or ".." in script_name:
        raise HTTPException(status_code=400, detail="Název skriptu nesmí obsahovat cestu")
    return script_name


def script_path(script_name: str) -> Path:
    safe_name = validate_script_name(script_name)
    path = (MAINTENANCE_DIR / safe_name).resolve()
    base = MAINTENANCE_DIR.resolve()
    try:
        path.relative_to(base)
    except ValueError:
        raise HTTPException(status_code=400, detail="Neplatný název skriptu")
    return path


def read_script_file(script_name: str) -> dict:
    path = script_path(script_name)
    if not path.exists():
        return {
            "exists": False,
            "content": DEFAULT_SCRIPT_CONTENT,
            "error": None,
            "warning": "Soubor zatím neexistuje. Můžete ho vytvořit z výchozího obsahu.",
        }
    if not path.is_file():
        return {"exists": False, "content": "", "error": "Cesta není soubor.", "warning": None}
    try:
        if path.stat().st_size > MAX_SCRIPT_BYTES:
            return {"exists": True, "content": "", "error": "Soubor je větší než 100 KB.", "warning": None}
        content = path.read_text(encoding="utf-8")
    except Exception:
        return {"exists": True, "content": "", "error": "Soubor se nepodařilo načíst.", "warning": None}

    warning = None
    if not content.startswith("#!/usr/bin/env bash"):
        warning = "První řádek by měl být #!/usr/bin/env bash."
    return {"exists": True, "content": content, "error": None, "warning": warning}


def normalize_script_content(content: str) -> str:
    value = content.replace("\r\n", "\n").replace("\r", "\n")
    if not value.strip():
        raise HTTPException(status_code=400, detail="Obsah skriptu nesmí být prázdný")
    if len(value.encode("utf-8")) > MAX_SCRIPT_BYTES:
        raise HTTPException(status_code=400, detail="Obsah skriptu je větší než 100 KB")
    if not value.startswith("#!/usr/bin/env bash"):
        value = "#!/usr/bin/env bash\n" + value.lstrip("\n")
    if len(value.encode("utf-8")) > MAX_SCRIPT_BYTES:
        raise HTTPException(status_code=400, detail="Obsah skriptu je větší než 100 KB")
    return value


def save_script_file(script_name: str, content: str) -> None:
    path = script_path(script_name)
    value = normalize_script_content(content)
    try:
        path.parent.mkdir(parents=True, exist_ok=True)
        path.write_text(value, encoding="utf-8", newline="\n")
    except OSError as exc:
        reason = exc.strerror or str(exc)
        raise HTTPException(status_code=500, detail=f"Soubor se nepodařilo uložit: {reason}")
    # Spustitelná práva nastavujeme best-effort – soubor už je uložený, takže selhání chmod
    # (jiný vlastník, FS bez podpory práv) nesmí hlásit chybu uložení.
    try:
        os.chmod(path, 0o755)
    except OSError:
        pass


def validate_schedule_type(value: str) -> str:
    schedule_type = clean_optional(value)
    if schedule_type not in SCHEDULE_TYPES:
        raise HTTPException(status_code=400, detail="Neplatná frekvence")
    return schedule_type


def validate_timeout(value: str | int) -> int:
    try:
        timeout_seconds = int(value)
    except (TypeError, ValueError):
        raise HTTPException(status_code=400, detail="Timeout musí být číslo")
    if timeout_seconds < 10 or timeout_seconds > 3600:
        raise HTTPException(status_code=400, detail="Timeout musí být mezi 10 a 3600 sekundami")
    return timeout_seconds


def form_metadata(
    name: str,
    description: str,
    schedule_type: str,
    schedule_time: str,
    timeout_seconds: str,
    is_enabled: str | None,
) -> dict:
    name_value = clean_optional(name)
    if not name_value:
        raise HTTPException(status_code=400, detail="Název je povinný")
    return {
        "name": name_value,
        "description": clean_optional(description),
        "schedule_type": validate_schedule_type(schedule_type),
        "schedule_time": clean_optional(schedule_time),
        "timeout_seconds": validate_timeout(timeout_seconds),
        "is_enabled": bool(is_enabled),
    }


def render_form(script: dict | None, action: str, include_script_name: bool) -> str:
    script = script or {}
    name = html.escape(script.get("name", "") or "")
    description = html.escape(script.get("description", "") or "")
    script_name = html.escape(script.get("script_name", "") or "")
    schedule_type = script.get("schedule_type", "daily") or "daily"
    schedule_time = html.escape(script.get("schedule_time", "") or "")
    timeout_seconds = html.escape(str(script.get("timeout_seconds") or 300))
    enabled_checked = " checked" if script.get("is_enabled", True) else ""
    script_name_input = ""
    if include_script_name:
        script_name_input = f"""
                <label>Skript</label>
                <input name="script_name" value="{script_name}" placeholder="maintenance.sh" required>
        """
    else:
        script_name_input = f"""
                <label>Skript</label>
                <input value="{script_name}" disabled>
        """

    return f"""
        <form method="post" action="{action}" class="metadata-form">
            <label>Název</label>
            <input name="name" value="{name}" required>

            <label>Popis</label>
            <textarea name="description" rows="3">{description}</textarea>

            {script_name_input}

            <label>Frekvence</label>
            <select name="schedule_type">{render_schedule_options(schedule_type)}</select>

            <label>Čas</label>
            <input name="schedule_time" value="{schedule_time}" placeholder="např. 02:30">

            <label>Timeout</label>
            <input name="timeout_seconds" value="{timeout_seconds}" inputmode="numeric" required>

            <label class="checkbox-label"><input type="checkbox" name="is_enabled" value="1"{enabled_checked}> Zapnuto</label>

            <div class="form-actions">
                <button type="submit"><i class="fa-solid fa-floppy-disk" aria-hidden="true"></i> Uložit</button>
            </div>
        </form>
    """


def render_script_content_section(script: dict, user: dict) -> str:
    script_name = script.get("script_name", "") or ""
    script_name_html = html.escape(script_name)
    try:
        script_file = read_script_file(script_name)
    except HTTPException:
        script_file = {
            "exists": False,
            "content": "",
            "error": "Název skriptu není bezpečný.",
            "warning": None,
        }
    content = html.escape(script_file.get("content", "") or "")
    warning = ""
    if script_file.get("warning"):
        warning = f'<p class="alert">{script_file["warning"]}</p>'
    error = ""
    if script_file.get("error"):
        error = f'<p class="alert alert-danger">{script_file["error"]}</p>'

    if not is_admin(user):
        readonly_hint = '<p class="muted">Obsah skriptu je dostupný pouze pro čtení. Ukládat může jen administrátor.</p>'
        return f"""
        <div class="card">
            <h2>Obsah skriptu</h2>
            <p><strong>Soubor:</strong> {script_name_html}</p>
            {warning}
            {error}
            {readonly_hint}
            <textarea rows="18" readonly>{content}</textarea>
        </div>
        """

    return f"""
        <div class="card">
            <h2>Obsah skriptu</h2>
            <p><strong>Soubor:</strong> {script_name_html}</p>
            {warning}
            {error}
            <form method="post" action="/portal/scheduled-scripts/{html.escape(str(script.get("id")))}/script" class="metadata-form">
                <label>Obsah souboru</label>
                <textarea name="content" rows="22" spellcheck="false">{content}</textarea>
                <div class="form-actions">
                    <button type="submit"><i class="fa-solid fa-floppy-disk" aria-hidden="true"></i> Uložit skript</button>
                </div>
            </form>
        </div>
    """


@router.get("/scheduled-scripts", response_class=HTMLResponse)
def scheduled_scripts_page(request: Request, user=Depends(require_user)):
    scripts = get_scheduled_scripts()
    rows = ""
    for script in scripts:
        script_id_raw = int(script.get("id"))
        script_id = html.escape(str(script_id_raw))
        name = html.escape(script.get("name", "") or "")
        script_name = html.escape(script.get("script_name", "") or "")
        schedule_type = render_schedule_type(script.get("schedule_type"))
        schedule_time = html.escape(script.get("schedule_time", "") or "")
        last_status = render_status_pill(script.get("last_status")) if script.get("last_status") else ""
        last_run_at = html.escape(script.get("last_run_at", "") or "")
        next_run_at = html.escape(script.get("next_run_at", "") or "")
        enabled = bool(script.get("is_enabled"))
        toggle_label = "Zakázat" if enabled else "Povolit"
        delete_button = ""
        if not script.get("is_running"):
            delete_button = f"""
                <form method="post" action="/portal/scheduled-scripts/{script_id}/delete" class="inline-form" onsubmit="return confirm('Smazat plánovaný skript {name}?');">
                    <button type="submit" class="icon-action icon-action-danger" title="Smazat" aria-label="Smazat"><i class="fa-solid fa-trash" aria-hidden="true"></i></button>
                </form>
            """

        rows += f"""
        <tr>
            <td><strong><a href="/portal/scheduled-scripts/{script_id}">{name}</a></strong></td>
            <td>{script_name}</td>
            <td>{schedule_type}</td>
            <td>{schedule_time}</td>
            <td>{render_enabled_pill(enabled)}</td>
            <td>{render_running_pill(script.get("is_running"))}</td>
            <td>{last_status}</td>
            <td>{last_run_at}</td>
            <td>{next_run_at}</td>
            <td class="actions-cell service-actions">
                <a class="icon-action" href="/portal/scheduled-scripts/{script_id}" title="Detail" aria-label="Detail"><i class="fa-solid fa-eye" aria-hidden="true"></i></a>
                <form method="post" action="/portal/scheduled-scripts/{script_id}/run-now" class="inline-form">
                    <button type="submit" class="icon-action" title="Spustit nyní" aria-label="Spustit nyní"><i class="fa-solid fa-play" aria-hidden="true"></i></button>
                </form>
                <form method="post" action="/portal/scheduled-scripts/{script_id}/toggle" class="inline-form">
                    <button type="submit" class="icon-action" title="{toggle_label}" aria-label="{toggle_label}"><i class="fa-solid fa-power-off" aria-hidden="true"></i></button>
                </form>
                {delete_button}
            </td>
        </tr>
        """

    if not rows:
        rows = '<tr><td colspan="10">Zatím nejsou evidované žádné plánované skripty.</td></tr>'

    return page(
        "Plánované skripty",
        f"""
        <div class="card">
            <h2><i class="fa-solid fa-calendar-days" aria-hidden="true"></i> Plánované skripty</h2>
            <p class="muted">Přehled skriptů spouštěných schedulerem nebo ručně z portálu.</p>
            <p><a class="btn" href="/portal/scheduled-scripts/new"><i class="fa-solid fa-plus" aria-hidden="true"></i> Nový plánovaný skript</a></p>
        </div>

        <div class="card">
            <h2>Seznam</h2>
            <table>
                <tr>
                    <th>Název</th>
                    <th>Skript</th>
                    <th>Frekvence</th>
                    <th>Čas</th>
                    <th>Zapnuto</th>
                    <th>Běží</th>
                    <th>Poslední stav</th>
                    <th>Poslední běh</th>
                    <th>Další běh</th>
                    <th>Akce</th>
                </tr>
                {rows}
            </table>
        </div>
        """,
        user=user,
    )


@router.get("/scheduled-scripts/new", response_class=HTMLResponse)
def new_scheduled_script_form(request: Request, user=Depends(require_user)):
    return page(
        "Nový plánovaný skript",
        f"""
        <div class="card">
            <h2><i class="fa-solid fa-circle-plus" aria-hidden="true"></i> Nový plánovaný skript</h2>
            <p><a class="btn" href="/portal/scheduled-scripts">&larr; Zpět</a></p>
        </div>
        <div class="card">
            {render_form({"is_enabled": True, "timeout_seconds": 300, "schedule_type": "daily"}, "/portal/scheduled-scripts/new", True)}
        </div>
        """,
        user=user,
    )


@router.post("/scheduled-scripts/new")
def create_scheduled_script_action(
    name: str = Form(...),
    description: str = Form(""),
    script_name: str = Form(...),
    schedule_type: str = Form(...),
    schedule_time: str = Form(""),
    timeout_seconds: str = Form("300"),
    is_enabled: str | None = Form(None),
    user=Depends(require_user),
):
    metadata = form_metadata(name, description, schedule_type, schedule_time, timeout_seconds, is_enabled)
    metadata["script_name"] = validate_script_name(script_name)
    script_id = create_scheduled_script(metadata)
    created_name = metadata["script_name"]
    if not script_path(created_name).exists():
        save_script_file(created_name, DEFAULT_SCRIPT_CONTENT)
        commit_and_push(f"maintenance/{created_name}", f"Vytvořen skript {created_name}", user)
    log_audit_event(
        user,
        action="scheduled_script.created",
        target_type="scheduled_script",
        target_id=script_id,
        metadata={"script_name": metadata["script_name"]},
    )
    return RedirectResponse(url=f"/portal/scheduled-scripts/{script_id}", status_code=303)


@router.get("/scheduled-scripts/{script_id}", response_class=HTMLResponse)
def scheduled_script_detail(script_id: int, request: Request, user=Depends(require_user)):
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")

    last_job_id = script.get("last_job_id")
    last_job = ""
    if last_job_id:
        last_job_html = html.escape(str(last_job_id))
        last_job = f'<a href="/portal/jobs/{last_job_html}">#{last_job_html}</a>'

    enabled = bool(script.get("is_enabled"))
    toggle_label = "Zakázat" if enabled else "Povolit"
    delete_form = ""
    if not script.get("is_running"):
        delete_form = f"""
            <form method="post" action="/portal/scheduled-scripts/{script_id}/delete" onsubmit="return confirm('Smazat plánovaný skript?');">
                <button type="submit" class="danger"><i class="fa-solid fa-trash" aria-hidden="true"></i> Smazat</button>
            </form>
        """
    script_content_section = render_script_content_section(script, user)

    return page(
        html.escape(script.get("name", "") or "Plánovaný skript"),
        f"""
        <div class="card">
            <h2><i class="fa-solid fa-calendar-day" aria-hidden="true"></i> {html.escape(script.get("name", "") or "")}</h2>
            <p>
                <a class="btn" href="/portal/scheduled-scripts">&larr; Zpět na plánované skripty</a>
                <a class="btn btn-secondary" href="/portal/scheduled-scripts/{script_id}/edit"><i class="fa-solid fa-pen-to-square" aria-hidden="true"></i> Upravit</a>
            </p>
            <div class="inline-form">
                <form method="post" action="/portal/scheduled-scripts/{script_id}/run-now">
                    <button type="submit"><i class="fa-solid fa-play" aria-hidden="true"></i> Spustit nyní</button>
                </form>
                <form method="post" action="/portal/scheduled-scripts/{script_id}/toggle">
                    <button type="submit" class="btn-secondary"><i class="fa-solid fa-power-off" aria-hidden="true"></i> {toggle_label}</button>
                </form>
                {delete_form}
            </div>
        </div>

        <div class="card">
            <h2>Souhrn</h2>
            <table>
                <tr><th>Název</th><td>{html.escape(script.get("name", "") or "")}</td></tr>
                <tr><th>Popis</th><td>{html.escape(script.get("description", "") or "")}</td></tr>
                <tr><th>Skript</th><td>{html.escape(script.get("script_name", "") or "")}</td></tr>
                <tr><th>Frekvence</th><td>{render_schedule_type(script.get("schedule_type"))}</td></tr>
                <tr><th>Čas</th><td>{html.escape(script.get("schedule_time", "") or "")}</td></tr>
                <tr><th>Timeout</th><td>{html.escape(str(script.get("timeout_seconds") or ""))}</td></tr>
                <tr><th>Zapnuto</th><td>{render_bool(script.get("is_enabled"))}</td></tr>
                <tr><th>Běží</th><td>{render_bool(script.get("is_running"))}</td></tr>
                <tr><th>Poslední stav</th><td>{render_status_pill(script.get("last_status")) if script.get("last_status") else ""}</td></tr>
                <tr><th>Poslední chyba</th><td>{html.escape(script.get("last_error_text", "") or "")}</td></tr>
                <tr><th>Poslední běh</th><td>{html.escape(script.get("last_run_at", "") or "")}</td></tr>
                <tr><th>Další běh</th><td>{html.escape(script.get("next_run_at", "") or "")}</td></tr>
                <tr><th>Poslední úloha</th><td>{last_job}</td></tr>
            </table>
        </div>

        {script_content_section}
        """,
        user=user,
    )


@router.get("/scheduled-scripts/{script_id}/edit", response_class=HTMLResponse)
def edit_scheduled_script_form(script_id: int, request: Request, user=Depends(require_user)):
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")
    return page(
        "Upravit plánovaný skript",
        f"""
        <div class="card">
            <h2><i class="fa-solid fa-pen-to-square" aria-hidden="true"></i> Upravit plánovaný skript</h2>
            <p><a class="btn" href="/portal/scheduled-scripts/{script_id}">&larr; Zpět</a></p>
        </div>
        <div class="card">
            {render_form(script, f"/portal/scheduled-scripts/{script_id}/edit", False)}
        </div>
        """,
        user=user,
    )


@router.post("/scheduled-scripts/{script_id}/edit")
def update_scheduled_script_action(
    script_id: int,
    name: str = Form(...),
    description: str = Form(""),
    schedule_type: str = Form(...),
    schedule_time: str = Form(""),
    timeout_seconds: str = Form("300"),
    is_enabled: str | None = Form(None),
    user=Depends(require_user),
):
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")
    metadata = form_metadata(name, description, schedule_type, schedule_time, timeout_seconds, is_enabled)
    update_scheduled_script(script_id, metadata)
    log_audit_event(
        user,
        action="scheduled_script.updated",
        target_type="scheduled_script",
        target_id=script_id,
        metadata={"script_name": script.get("script_name")},
    )
    return RedirectResponse(url=f"/portal/scheduled-scripts/{script_id}", status_code=303)


@router.post("/scheduled-scripts/{script_id}/run-now")
def run_scheduled_script_now(script_id: int, user=Depends(require_user)):
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")
    job_id = create_job(
        job_type="run_script",
        target_type="scheduled_script",
        target_id=script.get("script_name"),
        payload={
            "scheduled_script_id": script.get("id"),
            "script_name": script.get("script_name"),
            "timeout_seconds": script.get("timeout_seconds"),
        },
        user=user,
        source="portal_manual",
    )
    log_audit_event(
        user,
        action="scheduled_script.run_now",
        target_type="scheduled_script",
        target_id=script_id,
        metadata={"script_name": script.get("script_name"), "job_id": job_id},
    )
    return RedirectResponse(url=f"/portal/jobs/{job_id}", status_code=303)


@router.post("/scheduled-scripts/{script_id}/script")
def update_scheduled_script_file(
    script_id: int,
    content: str = Form(...),
    user=Depends(require_user),
):
    if not is_admin(user):
        raise HTTPException(status_code=403, detail="Skript může upravit pouze administrátor")
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")
    script_name = validate_script_name(script.get("script_name", "") or "")
    save_script_file(script_name, content)
    commit_and_push(f"maintenance/{script_name}", f"Úprava skriptu {script_name}", user)
    log_audit_event(
        user,
        action="scheduled_script.file_updated",
        target_type="scheduled_script",
        target_id=script_id,
        metadata={
            "scheduled_script_id": script_id,
            "script_name": script_name,
        },
    )
    return RedirectResponse(url=f"/portal/scheduled-scripts/{script_id}", status_code=303)


@router.post("/scheduled-scripts/{script_id}/toggle")
def toggle_scheduled_script(script_id: int, user=Depends(require_user)):
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")
    enabled = not bool(script.get("is_enabled"))
    set_scheduled_script_enabled(script_id, enabled)
    log_audit_event(
        user,
        action="scheduled_script.enabled" if enabled else "scheduled_script.disabled",
        target_type="scheduled_script",
        target_id=script_id,
        metadata={"script_name": script.get("script_name")},
    )
    return RedirectResponse(url=f"/portal/scheduled-scripts/{script_id}", status_code=303)


@router.post("/scheduled-scripts/{script_id}/delete")
def delete_scheduled_script_action(script_id: int, user=Depends(require_user)):
    script = get_scheduled_script(script_id)
    if not script:
        raise HTTPException(status_code=404, detail="Scheduled script not found")
    if script.get("is_running"):
        raise HTTPException(status_code=409, detail="Běžící skript nelze smazat")
    if not delete_scheduled_script(script_id):
        raise HTTPException(status_code=409, detail="Skript nelze smazat")
    script_name = clean_optional(script.get("script_name"))
    if script_name:
        path = script_path(script_name)
        if path.exists():
            path.unlink()
        commit_and_push(f"maintenance/{script_name}", f"Smazán skript {script_name}", user)
    log_audit_event(
        user,
        action="scheduled_script.deleted",
        target_type="scheduled_script",
        target_id=script_id,
        metadata={"script_name": script.get("script_name")},
    )
    return RedirectResponse(url="/portal/scheduled-scripts", status_code=303)