package de.ticketsystem.web.handlers;

import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import de.ticketsystem.TicketPlugin;
import de.ticketsystem.database.DatabaseManager;
import de.ticketsystem.model.*;
import de.ticketsystem.web.SessionManager;
import de.ticketsystem.web.WebSession;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.stream.Collectors;

/**
 * /tickets        – Liste aller Tickets (gefiltert, paginiert)
 * /ticket/{id}    – Detailansicht eines Tickets
 */
public class TicketsHandler extends BaseHandler implements HttpHandler {

    private static final int PAGE_SIZE = 20;
    private final SimpleDateFormat SDF = new SimpleDateFormat("dd.MM.yyyy HH:mm");

    private final TicketPlugin   plugin;
    private final SessionManager sessionManager;

    public TicketsHandler(TicketPlugin plugin, SessionManager sessionManager) {
        this.plugin         = plugin;
        this.sessionManager = sessionManager;
    }

    @Override
    public void handle(HttpExchange ex) throws IOException {
        WebSession session = requireSession(ex, sessionManager);
        if (session == null) return;

        String path = ex.getRequestURI().getPath();

        if (path.startsWith("/ticket/") && path.length() > 8) {
            String idStr = path.substring(8).replaceAll("[^0-9]", "");
            if (!idStr.isEmpty()) {
                handleDetail(ex, session, Integer.parseInt(idStr));
                return;
            }
        }

        handleList(ex, session);
    }

    // ─────────────────────────── Ticket-Liste ──────────────────────────────

    private void handleList(HttpExchange ex, WebSession session) throws IOException {
        Map<String, String> params = parseQuery(ex.getRequestURI().getQuery());

        String filterStatus   = params.getOrDefault("status",   "all");
        String filterCat      = params.getOrDefault("category", "all");
        String filterPrio     = params.getOrDefault("priority", "all");
        String filterSearch   = params.getOrDefault("q",        "").trim();
        int    page           = parseInt(params.getOrDefault("page", "1"), 1);

        DatabaseManager db = plugin.getDatabaseManager();
        List<Ticket> all = db.getAllTickets();

        // ── Filter ──
        List<Ticket> filtered = all.stream()
                .filter(t -> filterStatus.equals("all") || t.getStatus().name().equalsIgnoreCase(filterStatus))
                .filter(t -> filterCat.equals("all") || t.getCategoryKey().equalsIgnoreCase(filterCat))
                .filter(t -> filterPrio.equals("all") || t.getPriority().name().equalsIgnoreCase(filterPrio))
                .filter(t -> filterSearch.isEmpty()
                        || t.getCreatorName().toLowerCase().contains(filterSearch.toLowerCase())
                        || t.getMessage().toLowerCase().contains(filterSearch.toLowerCase())
                        || String.valueOf(t.getId()).contains(filterSearch))
                .sorted(Comparator.comparingInt(Ticket::getId).reversed())
                .collect(Collectors.toList());

        // ── Paginierung ──
        int total     = filtered.size();
        int totalPages = Math.max(1, (int) Math.ceil(total / (double) PAGE_SIZE));
        page = Math.max(1, Math.min(page, totalPages));
        int fromIdx = (page - 1) * PAGE_SIZE;
        int toIdx   = Math.min(fromIdx + PAGE_SIZE, total);
        List<Ticket> pageTickets = filtered.subList(fromIdx, toIdx);

        String content = buildList(pageTickets, total, page, totalPages,
                filterStatus, filterCat, filterPrio, filterSearch);
        sendHtml(ex, 200, layout(wl(plugin, "tickets-title"), content, session, plugin));
    }

    private String buildList(List<Ticket> tickets, int total, int page, int totalPages,
                             String filterStatus, String filterCat, String filterPrio, String filterSearch) {
        StringBuilder sb = new StringBuilder();
        sb.append("<h1 class='page-title'>")
          .append(escHtml(wl(plugin, "tickets-title")))
          .append(" <span>").append(total).append(" ")
          .append(escHtml(wl(plugin, "tickets-total")))
          .append("</span></h1>");

        // ── Filter-Bar ──
        sb.append("<div class='filter-bar'>");
        sb.append(selectFilter("status", filterStatus, List.of(
                entry("all",       wl(plugin, "filter-all-status")),
                entry("OPEN",      wl(plugin, "filter-open")),
                entry("CLAIMED",   wl(plugin, "filter-claimed")),
                entry("FORWARDED", wl(plugin, "filter-forwarded")),
                entry("CLOSED",    wl(plugin, "filter-closed")))));

        if (plugin.getConfig().getBoolean("categories-enabled", true)) {
            List<Map.Entry<String,String>> catOpts = new ArrayList<>();
            catOpts.add(entry("all", wl(plugin, "filter-all-cat")));
            plugin.getCategoryManager().getAll().forEach(c -> catOpts.add(entry(c.getKey(), c.getName())));
            sb.append(selectFilter("category", filterCat, catOpts));
        }

        if (plugin.getConfig().getBoolean("priorities-enabled", true)) {
            sb.append(selectFilter("priority", filterPrio, List.of(
                    entry("all",    wl(plugin, "filter-all-prio")),
                    entry("LOW",    wl(plugin, "filter-low")),
                    entry("NORMAL", wl(plugin, "filter-normal")),
                    entry("HIGH",   wl(plugin, "filter-high")),
                    entry("URGENT", wl(plugin, "filter-urgent")))));
        }

        sb.append("<form method='GET' action='/tickets' style='display:flex;gap:.5rem'>");
        sb.append("<input name='q' placeholder='")
          .append(escHtml(wl(plugin, "tickets-search-ph")))
          .append("' value='").append(escHtml(filterSearch)).append("'style='width:180px'>");
        sb.append("<input name='status' type='hidden' value='").append(escHtml(filterStatus)).append("'>");
        sb.append("<input name='category' type='hidden' value='").append(escHtml(filterCat)).append("'>");
        sb.append("<input name='priority' type='hidden' value='").append(escHtml(filterPrio)).append("'>");
        sb.append("<button type='submit' class='btn btn-secondary btn-sm'>🔍</button></form>");
        sb.append("</div>");

        // ── Tabelle ──
        sb.append("<div class='card'><table><thead><tr>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-id"))).append("</th>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-player"))).append("</th>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-message"))).append("</th>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-cat"))).append("</th>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-prio"))).append("</th>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-status"))).append("</th>")
          .append("<th>").append(escHtml(wl(plugin, "tickets-col-created"))).append("</th>")
          .append("<th></th>")
          .append("</tr></thead><tbody>");

        for (Ticket t : tickets) {
            String msg = t.getMessage() != null && t.getMessage().length() > 60
                    ? t.getMessage().substring(0, 60) + "…" : t.getMessage();
            String created = t.getCreatedAt() != null ? SDF.format(t.getCreatedAt()) : "—";
            String catName = getCategoryName(t);

            sb.append("<tr>")
              .append("<td><strong>#").append(t.getId()).append("</strong></td>")
              .append("<td>").append(escHtml(t.getCreatorName())).append("</td>")
              .append("<td>").append(escHtml(msg)).append("</td>")
              .append("<td>").append(escHtml(catName)).append("</td>")
              .append("<td>").append(priorityBadge(t)).append("</td>")
              .append("<td>").append(statusBadge(t)).append("</td>")
              .append("<td style='white-space:nowrap'>").append(created).append("</td>")
              .append("<td><a href='/ticket/").append(t.getId())
              .append("' class='btn btn-sm btn-secondary'>")
              .append(escHtml(wl(plugin, "btn-details")))
              .append("</a></td>")
              .append("</tr>");
        }

        if (tickets.isEmpty()) {
            sb.append("<tr><td colspan='8' style='text-align:center;color:var(--muted);padding:2rem'>")
              .append(escHtml(wl(plugin, "tickets-empty")))
              .append("</td></tr>");
        }

        sb.append("</tbody></table></div>");

        // ── Paginierung ──
        if (totalPages > 1) {
            sb.append("<div class='pagination'>");
            for (int i = 1; i <= totalPages; i++) {
                String active = i == page ? " active" : "";
                sb.append("<a class='page-btn").append(active).append("' href='/tickets?page=").append(i)
                  .append("&status=").append(filterStatus)
                  .append("&category=").append(filterCat)
                  .append("&priority=").append(filterPrio)
                  .append("&q=").append(escHtml(filterSearch))
                  .append("'>").append(i).append("</a>");
            }
            sb.append("</div>");
        }

        return sb.toString();
    }

    // ─────────────────────────── Ticket-Detail ─────────────────────────────

    private void handleDetail(HttpExchange ex, WebSession session, int ticketId) throws IOException {
        Ticket ticket = plugin.getDatabaseManager().getTicketById(ticketId);
        if (ticket == null) {
            sendHtml(ex, 404, errorPage(
                    wl(plugin, "detail-not-found"),
                    wl(plugin, "detail-not-found") + " #" + ticketId,
                    plugin));
            return;
        }

        List<TicketComment> comments = plugin.getDatabaseManager().getComments(ticketId);
        String content = buildDetail(ticket, comments, session);
        sendHtml(ex, 200, layout("Ticket #" + ticketId, content, session, plugin));
    }

    private String buildDetail(Ticket t, List<TicketComment> comments, WebSession session) {
        StringBuilder sb = new StringBuilder();
        String created = t.getCreatedAt() != null ? SDF.format(t.getCreatedAt()) : "—";
        String catName = getCategoryName(t);

        // ── Header ──
        sb.append("<div style='margin-bottom:1.5rem'>");
        sb.append("<a href='/tickets' class='btn btn-sm btn-secondary' style='margin-bottom:1rem'>")
          .append(escHtml(wl(plugin, "detail-back"))).append("</a>");
        sb.append("</div>");
        sb.append("<div class='ticket-header'>");
        sb.append("<div class='ticket-id'>#").append(t.getId()).append("</div>");
        sb.append("<div class='ticket-meta'>");
        sb.append(statusBadge(t)).append(" ").append(priorityBadge(t));
        sb.append("<span class='badge' style='background:var(--surface2);color:var(--muted)'>")
          .append(escHtml(catName)).append("</span>");
        if (plugin.isBungeeCordEnabled()) {
            sb.append("<span class='badge' style='background:var(--surface2);color:var(--muted)'>🌐 ")
              .append(escHtml(t.getServerName())).append("</span>");
        }
        sb.append("</div></div>");

        // ── Info-Grid ──
        sb.append("<div class='info-grid'>");
        infoRow(sb, wl(plugin, "detail-info-creator"),   t.getCreatorName());
        infoRow(sb, wl(plugin, "detail-info-created"),   created);
        infoRow(sb, wl(plugin, "detail-info-claimer"),   t.getClaimerName() != null ? t.getClaimerName() : "—");
        infoRow(sb, wl(plugin, "detail-info-forwarded"), t.getForwardedToName() != null ? t.getForwardedToName() : "—");
        if (t.getWorldName() != null) {
            infoRow(sb, wl(plugin, "detail-info-position"), String.format("%s %.0f / %.0f / %.0f",
                    t.getWorldName(), t.getX(), t.getY(), t.getZ()));
        }
        if (t.getPlayerRating() != null) {
            String ratingText = "THUMBS_UP".equals(t.getPlayerRating())
                    ? wl(plugin, "detail-rating-pos")
                    : wl(plugin, "detail-rating-neg");
            infoRow(sb, wl(plugin, "detail-info-rating"), ratingText);
        }
        sb.append("</div>");

        // ── Nachricht ──
        sb.append("<div class='card-title'>").append(escHtml(wl(plugin, "detail-section-msg"))).append("</div>");
        sb.append("<div class='ticket-message'>").append(escHtml(t.getMessage())).append("</div>");

        if (t.getCloseComment() != null && !t.getCloseComment().isEmpty()) {
            sb.append("<div class='card-title'>").append(escHtml(wl(plugin, "detail-section-closecomment"))).append("</div>");
            sb.append("<div class='ticket-message'>").append(escHtml(t.getCloseComment())).append("</div>");
        }

        // ── Aktionen (nur bei aktiven Tickets) ──
        if (t.getStatus() != TicketStatus.CLOSED) {
            sb.append("<div class='card'><div class='card-title'>")
              .append(escHtml(wl(plugin, "detail-section-actions")))
              .append("</div><div style='display:flex;flex-wrap:wrap;gap:.75rem'>");

            // Claim
            if (t.getStatus() == TicketStatus.OPEN) {
                sb.append("<button class='btn btn-success' onclick='claimTicket(").append(t.getId()).append(")'>")
                  .append(escHtml(wl(plugin, "detail-btn-claim"))).append("</button>");
            }

            // Priorität
            if (plugin.getConfig().getBoolean("priorities-enabled", true)) {
                sb.append("<select id='prio-select-").append(t.getId())
                  .append("' class='btn btn-secondary' style='width:auto' onchange='setPriority(")
                  .append(t.getId()).append(", this.value)'>");
                for (TicketPriority p : TicketPriority.values()) {
                    String sel = p == t.getPriority() ? " selected" : "";
                    sb.append("<option value='").append(p.name()).append("'").append(sel).append(">")
                      .append(escHtml(p.getDisplayName())).append("</option>");
                }
                sb.append("</select>");
            }

            // Weiterleiten (nur Admin)
            if (session.isAdmin()) {
                sb.append("<input id='forward-target-").append(t.getId())
                  .append("' class='btn btn-secondary' style='width:180px' placeholder='")
                  .append(escHtml(wl(plugin, "detail-ph-forward"))).append("'>");
                sb.append("<button class='btn btn-warning' onclick='forwardTicket(").append(t.getId()).append(")'>")
                  .append(escHtml(wl(plugin, "detail-btn-forward"))).append("</button>");
            }

            // Schließen
            sb.append("<div style='display:flex;gap:.5rem;align-items:center'>");
            sb.append("<input id='close-comment-").append(t.getId())
              .append("' placeholder='").append(escHtml(wl(plugin, "detail-ph-comment")))
              .append("' style='width:220px'>");
            sb.append("<button class='btn btn-danger' onclick='closeTicket(").append(t.getId()).append(")'>")
              .append(escHtml(wl(plugin, "detail-btn-close"))).append("</button>");
            sb.append("</div>");

            sb.append("</div></div>");
        }

        // ── Kommentare ──
        sb.append("<div class='card'><div class='card-title'>")
          .append(escHtml(wl(plugin, "detail-section-comments")))
          .append(" (").append(comments.size()).append(")</div>");
        sb.append("<div class='comments'>");
        for (TicketComment c : comments) {
            String cTime = c.getCreatedAt() != null ? SDF.format(c.getCreatedAt()) : "";
            sb.append("<div class='comment'>");
            sb.append("<span class='comment-author'>").append(escHtml(c.getAuthorName())).append("</span>");
            sb.append("<span class='comment-time'>").append(cTime).append("</span>");
            sb.append("<div class='comment-text'>").append(escHtml(c.getMessage())).append("</div>");
            sb.append("</div>");
        }
        if (comments.isEmpty()) {
            sb.append("<div style='color:var(--muted);font-size:.875rem'>")
              .append(escHtml(wl(plugin, "detail-no-comments"))).append("</div>");
        }
        sb.append("</div>");

        // Neuer Kommentar
        if (t.getStatus() != TicketStatus.CLOSED) {
            sb.append("<div style='display:flex;gap:.75rem;margin-top:1rem'>");
            sb.append("<textarea id='comment-input-").append(t.getId())
              .append("' placeholder='").append(escHtml(wl(plugin, "detail-ph-newcomment")))
              .append("' style='flex:1;min-height:60px'></textarea>");
            sb.append("<button class='btn btn-primary' onclick='addComment(").append(t.getId()).append(")'>")
              .append(escHtml(wl(plugin, "detail-btn-send"))).append("</button>");
            sb.append("</div>");
        }
        sb.append("</div>");

        return sb.toString();
    }

    // ─────────────────────────── Hilfsmethoden ─────────────────────────────

    private String statusBadge(Ticket t) {
        String s = t.getStatus().name().toLowerCase();
        return "<span class='badge badge-" + s + "'>" + escHtml(t.getStatus().getDisplayName()) + "</span>";
    }

    private String priorityBadge(Ticket t) {
        String p = t.getPriority().name().toLowerCase();
        return "<span class='badge badge-" + p + "'>" + escHtml(t.getPriority().getDisplayName()) + "</span>";
    }

    private String getCategoryName(Ticket t) {
        var cat = plugin.getCategoryManager().fromKey(t.getCategoryKey());
        return cat != null ? cat.getName() : t.getCategoryKey();
    }

    private void infoRow(StringBuilder sb, String label, String value) {
        sb.append("<div class='info-row'><span class='info-label'>").append(escHtml(label)).append("</span>")
          .append("<span>").append(escHtml(value != null ? value : "—")).append("</span></div>");
    }

    private String selectFilter(String name, String current, List<Map.Entry<String,String>> options) {
        StringBuilder sb = new StringBuilder("<select name='").append(name)
                .append("' class='btn btn-secondary btn-sm' onchange='this.form.submit()'>");
        for (var opt : options) {
            String sel = opt.getKey().equals(current) ? " selected" : "";
            sb.append("<option value='").append(escHtml(opt.getKey())).append("'").append(sel).append(">")
              .append(escHtml(opt.getValue())).append("</option>");
        }
        return sb.append("</select>").toString();
    }

    private static Map.Entry<String,String> entry(String k, String v) {
        return Map.entry(k, v);
    }

    private static int parseInt(String s, int fallback) {
        try { return Integer.parseInt(s); } catch (NumberFormatException e) { return fallback; }
    }
}