'use client'

import { useState } from 'react'
import Link from 'next/link'
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
import { useTranslation } from 'react-i18next'
import { Plus } from 'lucide-react'
import { toast } from 'sonner'
import { api, type PaginatedResponse, type Project } from '@/lib/api'
import { DataTable } from '@/components/DataTable'
import { Button } from '@/components/ui/Button'
import { Badge } from '@/components/ui/Badge'
import { Select } from '@/components/ui/Select'
import { PermissionGate } from '@/components/auth/PermissionGate'

const statusVariant = (status: string) => {
  if (status === 'active') return 'success'
  if (status === 'completed') return 'success'
  if (status === 'on_hold') return 'warning'
  if (status === 'cancelled') return 'danger'
  return 'muted'
}

export function ProjectsPage() {
  const { t } = useTranslation()
  const queryClient = useQueryClient()
  const [search, setSearch] = useState('')
  const [status, setStatus] = useState('')
  const [page, setPage] = useState(1)

  const { data, isLoading } = useQuery({
    queryKey: ['projects', search, status, page],
    queryFn: () =>
      api.get<PaginatedResponse<Project>>('/projects', {
        params: { search: search || undefined, status: status || undefined, page, per_page: 25 },
      }),
  })

  const remove = useMutation({
    mutationFn: (id: number) => api.delete(`/projects/${id}`),
    onSuccess: () => {
      toast.success(t('projects.messages.deleted'))
      queryClient.invalidateQueries({ queryKey: ['projects'] })
    },
    onError: () => toast.error(t('common.somethingWentWrong')),
  })

  const projects = data?.data.data ?? []
  const meta = data?.data.meta

  const statusOptions = [
    { value: '', label: t('common.allStatuses') },
    ...(['draft', 'active', 'on_hold', 'completed', 'cancelled'] as const).map((value) => ({
      value,
      label: t(`projects.status.${value}`),
    })),
  ]

  return (
    <div className="space-y-5">
      <div className="animate-fade-in-up flex flex-wrap items-center justify-between gap-3">
        <h1 className="premium-heading text-2xl font-bold" data-tour="page-heading">{t('projects.title')}</h1>
        <PermissionGate permission="projects.manage">
          <Link href="/projects/new" data-tour="create-button">
            <Button size="sm">
              <Plus size={14} />
              {t('projects.create')}
            </Button>
          </Link>
        </PermissionGate>
      </div>

      <div className="animate-fade-in-up stagger-1">
        <DataTable
          data={projects}
          loading={isLoading}
          emptyMessage={t('common.noResults')}
          onSearch={(q) => {
            setSearch(q)
            setPage(1)
          }}
          searchValue={search}
          searchPlaceholder={t('projects.search')}
          toolbar={
            <Select
              value={status}
              onChange={(e) => {
                setStatus(e.target.value)
                setPage(1)
              }}
              options={statusOptions}
            />
          }
          pagination={meta}
          onPageChange={setPage}
          columns={[
            { key: 'project_code', header: t('common.code'), className: 'font-mono text-xs' },
            { key: 'name', header: t('projects.name') },
            {
              key: 'partner',
              header: t('projects.partner'),
              render: (r) => r.partner?.name || '—',
            },
            {
              key: 'status',
              header: t('common.status'),
              render: (r) => (
                <Badge variant={statusVariant(r.status)}>
                  {t(`projects.status.${r.status}`, r.status)}
                </Badge>
              ),
            },
            {
              key: 'progress',
              header: t('projects.progress'),
              render: (r) => `${r.progress ?? 0}%`,
            },
            {
              key: 'budget_variance',
              header: t('projects.budgetVariance'),
              render: (r) =>
                r.budget_variance != null ? Number(r.budget_variance).toLocaleString() : '—',
            },
            {
              key: 'actions',
              header: t('common.actions'),
              className: 'text-right',
              render: (r) => (
                <div className="flex justify-end gap-2">
                  <Link
                    href={`/projects/${r.id}`}
                    className="rounded-lg px-2 py-1 text-xs font-semibold text-accent-600 hover:bg-[var(--premium-hover-bg)] dark:text-accent-400"
                  >
                    {t('common.view')}
                  </Link>
                  <PermissionGate permission="projects.manage">
                    <Link
                      href={`/projects/${r.id}/edit`}
                      className="rounded-lg px-2 py-1 text-xs font-semibold text-accent-600 hover:bg-[var(--premium-hover-bg)] dark:text-accent-400"
                    >
                      {t('common.edit')}
                    </Link>
                    <button
                      type="button"
                      className="rounded-lg px-2 py-1 text-xs font-semibold text-red-500 hover:bg-red-500/10"
                      onClick={() => {
                        if (window.confirm(t('common.confirmDelete'))) remove.mutate(r.id)
                      }}
                    >
                      {t('common.delete')}
                    </button>
                  </PermissionGate>
                </div>
              ),
            },
          ]}
        />
      </div>
    </div>
  )
}