"use client";

import { useMemo, useState, useEffect } from "react";
import { useWorkSessions } from "@/hooks/use-work-sessions";
import { WorkSessionStatus } from "@/types";
import { OfflineState } from "@/components/ui/offline-state";
import { WorkSessionTable } from "./work-session-table";
import { WorkSessionFilters } from "./work-session-filters";
import { SessionTrendChart } from "./session-trend-chart";
import { usePageRefresh } from "@/hooks";

/**
 * Work-sessions content, rendered as the "Work Sessions" tab of /git.
 * Filter state is LOCAL, deliberately not URL params: every URL write forks
 * ScrollRestoration's route key and force-scrolls <main> to top, so a
 * per-keystroke q= param made typing in the search box bounce the page.
 */
export function WorkSessionsView() {
  const [searchQuery, setSearchQuery] = useState("");
  const [statusFilter, setStatusFilter] = useState<WorkSessionStatus[]>([]);

  const handleSearchChange = setSearchQuery;
  const handleStatusChange = setStatusFilter;

  // Fetch work sessions
  const { data: sessions, isLoading, error, refetch } = useWorkSessions();

  const { register, unregister, refresh } = usePageRefresh();

  useEffect(() => {
    const cb = () => {
      void refetch();
    };
    register(cb);
    return () => unregister(cb);
  }, [register, unregister, refetch]);

  // Filter sessions client-side for search and multi-select status filter
  const filteredSessions = useMemo(() => {
    if (!sessions) return [];

    return sessions.filter((session) => {
      // Search filter - match branch name
      if (
        searchQuery &&
        !session.branch_name.toLowerCase().includes(searchQuery.toLowerCase())
      ) {
        return false;
      }

      // Status filter (if any selected, session must match one of them)
      if (statusFilter.length > 0 && !statusFilter.includes(session.status)) {
        return false;
      }

      return true;
    });
  }, [sessions, searchQuery, statusFilter]);

  // Check if it's a connection error (backend not running)
  const isOffline =
    error &&
    (error.message?.includes("Network Error") ||
      error.message?.includes("ECONNREFUSED") ||
      (error as { code?: string })?.code === "ERR_NETWORK");

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-3xl font-bold tracking-tight">Work Sessions</h1>
          <p className="text-muted-foreground">
            Track git branches and pull requests for active work
          </p>
        </div>
      </div>

      {/* Filters - Sticky */}
      <div className="sticky top-0 z-10 -mx-6 px-6 py-2 bg-muted/30 backdrop-blur-sm">
        <WorkSessionFilters
          searchQuery={searchQuery}
          onSearchChange={handleSearchChange}
          statusFilter={statusFilter}
          onStatusChange={handleStatusChange}
        />
      </div>

      {/* Content */}
      {isOffline ? (
        <OfflineState
          title="Cannot Load Work Sessions"
          description="Start the RoboCo orchestrator to view work sessions. Work sessions track agent activity on git branches."
          onRetry={() => void refresh()}
        />
      ) : (
        <>
          <SessionTrendChart sessions={filteredSessions} isLoading={isLoading} />
          <WorkSessionTable sessions={filteredSessions} isLoading={isLoading} />
        </>
      )}
    </div>
  );
}