"use client"

import { useState } from "react"
import { toast } from "sonner"
import { formatDistanceToNow } from "date-fns"
import {
  Plus, Play, Trash2, ToggleLeft, ToggleRight,
  Loader2, Bell, DollarSign, Wrench, FileText, Home, X,
} from "lucide-react"

const RULE_TYPES = [
  { value: "overdue_rent",     label: "Overdue Rent Reminder",    icon: DollarSign, color: "text-red-400",     desc: "Remind tenants when rent is overdue" },
  { value: "maintenance_stale",label: "Stale Maintenance Alert",  icon: Wrench,     color: "text-orange-400",  desc: "Follow up on open maintenance requests" },
  { value: "lease_renewal",    label: "Lease Renewal Notice",     icon: FileText,   color: "text-blue-400",    desc: "Alert tenants about expiring leases" },
  { value: "vacant_unit",      label: "Vacant Unit Reminder",     icon: Home,       color: "text-amber-400",   desc: "Internal alerts for vacant units" },
]

const typeColors: Record<string, string> = {
  overdue_rent:      "text-red-400 bg-red-500/10",
  maintenance_stale: "text-orange-400 bg-orange-500/10",
  lease_renewal:     "text-blue-400 bg-blue-500/10",
  vacant_unit:       "text-amber-400 bg-amber-500/10",
}

export function FollowUpsClient({ rules: initial, logs: initialLogs }: { rules: any[]; logs: any[] }) {
  const [rules, setRules] = useState(initial)
  const [logs, setLogs] = useState(initialLogs)
  const [running, setRunning] = useState(false)
  const [showForm, setShowForm] = useState(false)
  const [saving, setSaving] = useState(false)
  const [form, setForm] = useState({ type: "overdue_rent", name: "", trigger_days: 3, message_template: "" })

  async function runFollowUps() {
    setRunning(true)
    try {
      const res = await fetch("/api/follow-ups/run", { method: "POST" })
      const data = await res.json()
      if (!res.ok) { toast.error(data.error ?? "Failed to run"); return }
      if (data.sent === 0) {
        toast.info("No follow-ups triggered — all rules are up to date")
      } else {
        toast.success(`${data.sent} follow-up${data.sent !== 1 ? "s" : ""} triggered`)
        setLogs((prev) => [...data.results, ...prev].slice(0, 30))
      }
      // refresh last_run_at
      const refreshed = await fetch("/api/follow-ups")
      const refreshedData = await refreshed.json()
      setRules(refreshedData.rules ?? rules)
    } catch {
      toast.error("Network error — please try again")
    } finally {
      setRunning(false)
    }
  }

  async function saveRule() {
    if (!form.name.trim()) return
    setSaving(true)
    try {
      const res = await fetch("/api/follow-ups", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify(form),
      })
      const data = await res.json()
      if (!res.ok) { toast.error(data.error ?? "Failed to save"); return }
      setRules((prev) => [...prev, data])
      setShowForm(false)
      setForm({ type: "overdue_rent", name: "", trigger_days: 3, message_template: "" })
      toast.success("Rule added")
    } catch {
      toast.error("Network error")
    } finally {
      setSaving(false)
    }
  }

  async function toggleRule(id: string, is_active: boolean) {
    const res = await fetch(`/api/follow-ups/${id}`, {
      method: "PATCH",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ is_active: !is_active }),
    })
    const data = await res.json()
    if (!res.ok) { toast.error(data.error ?? "Failed to update"); return }
    setRules((prev) => prev.map((r) => r.id === id ? data : r))
  }

  async function deleteRule(id: string) {
    await fetch(`/api/follow-ups/${id}`, { method: "DELETE" })
    setRules((prev) => prev.filter((r) => r.id !== id))
    toast.success("Rule deleted")
  }

  const cls = "w-full rounded-lg border border-white/10 bg-white/5 px-3 py-2.5 text-sm text-white placeholder-white/30 outline-none focus:border-indigo-500/50 focus:ring-1 focus:ring-indigo-500 transition"

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex items-end justify-between">
        <div>
          <h2 className="text-lg font-semibold text-white flex items-center gap-2">
            <Bell className="h-5 w-5 text-indigo-400" />
            Automated Follow-ups
          </h2>
          <p className="text-sm text-white/40 mt-0.5">Set rules and run them manually to trigger follow-up actions</p>
        </div>
        <div className="flex items-center gap-2">
          <button
            onClick={() => setShowForm(true)}
            className="flex items-center gap-1.5 rounded-xl border border-white/10 px-3 py-2 text-xs font-medium text-white/60 hover:text-white transition"
          >
            <Plus className="h-3.5 w-3.5" /> Add Rule
          </button>
          <button
            onClick={runFollowUps}
            disabled={running || rules.filter((r) => r.is_active).length === 0}
            className="flex items-center gap-2 rounded-xl bg-indigo-600 px-4 py-2 text-sm font-semibold text-white hover:bg-indigo-500 disabled:opacity-50 transition"
          >
            {running ? <Loader2 className="h-4 w-4 animate-spin" /> : <Play className="h-4 w-4" />}
            {running ? "Running…" : "Run Now"}
          </button>
        </div>
      </div>

      {/* Add rule form */}
      {showForm && (
        <div className="rounded-2xl border border-indigo-500/20 bg-[#16161f] p-5 space-y-4">
          <div className="flex items-center justify-between">
            <p className="text-sm font-semibold text-white">New Follow-up Rule</p>
            <button onClick={() => setShowForm(false)} className="text-white/30 hover:text-white transition"><X className="h-4 w-4" /></button>
          </div>
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="text-xs text-white/40 mb-1 block">Rule Name *</label>
              <input value={form.name} onChange={(e) => setForm((f) => ({ ...f, name: e.target.value }))} placeholder="e.g. 3-day overdue reminder" className={cls} />
            </div>
            <div>
              <label className="text-xs text-white/40 mb-1 block">Type *</label>
              <select value={form.type} onChange={(e) => setForm((f) => ({ ...f, type: e.target.value }))} className={cls}>
                {RULE_TYPES.map((t) => <option key={t.value} value={t.value}>{t.label}</option>)}
              </select>
            </div>
          </div>
          <div>
            <label className="text-xs text-white/40 mb-1 block">
              Trigger after{" "}
              <input
                type="number"
                min={1}
                max={90}
                value={form.trigger_days}
                onChange={(e) => setForm((f) => ({ ...f, trigger_days: parseInt(e.target.value) || 1 }))}
                className="mx-1 w-14 rounded border border-white/10 bg-white/5 px-2 py-0.5 text-sm text-white text-center outline-none focus:border-indigo-500"
              />
              {" "}days
            </label>
          </div>
          <div>
            <label className="text-xs text-white/40 mb-1 block">Custom message (optional — leave blank for default)</label>
            <textarea value={form.message_template} onChange={(e) => setForm((f) => ({ ...f, message_template: e.target.value }))} rows={3} placeholder="Leave blank to use the default message…" className={cls} />
          </div>
          <div className="flex gap-3 pt-1">
            <button onClick={() => setShowForm(false)} className="rounded-xl border border-white/10 px-4 py-2 text-sm text-white/40 hover:text-white transition">Cancel</button>
            <button onClick={saveRule} disabled={saving || !form.name.trim()} className="flex-1 rounded-xl bg-indigo-600 px-4 py-2 text-sm font-semibold text-white hover:bg-indigo-500 disabled:opacity-50 transition">
              {saving ? "Saving…" : "Save Rule"}
            </button>
          </div>
        </div>
      )}

      {/* Rules list */}
      {rules.length === 0 ? (
        <div className="rounded-xl border border-white/[0.06] bg-[#16161f] py-14 text-center">
          <Bell className="h-8 w-8 text-white/10 mx-auto mb-3" />
          <p className="text-sm text-white/30">No follow-up rules yet</p>
          <p className="text-xs text-white/20 mt-1">Add rules to automate reminders for overdue rent, maintenance, and lease renewals</p>
        </div>
      ) : (
        <div className="space-y-2">
          {rules.map((rule) => {
            const typeInfo = RULE_TYPES.find((t) => t.value === rule.type)
            const Icon = typeInfo?.icon ?? Bell
            return (
              <div key={rule.id} className={`rounded-xl border border-white/[0.06] bg-[#16161f] p-4 flex items-center gap-4 ${!rule.is_active ? "opacity-50" : ""}`}>
                <div className={`flex h-9 w-9 shrink-0 items-center justify-center rounded-xl ${typeColors[rule.type] ?? "text-white/40 bg-white/5"}`}>
                  <Icon className="h-4 w-4" />
                </div>
                <div className="flex-1 min-w-0">
                  <p className="text-sm font-semibold text-white">{rule.name}</p>
                  <p className="text-xs text-white/40 mt-0.5">
                    {typeInfo?.desc} · Triggers after {rule.trigger_days} day{rule.trigger_days !== 1 ? "s" : ""}
                    {rule.last_run_at && <span className="ml-2 text-white/25">Last run {formatDistanceToNow(new Date(rule.last_run_at), { addSuffix: true })}</span>}
                  </p>
                </div>
                <div className="flex items-center gap-1 shrink-0">
                  <button onClick={() => toggleRule(rule.id, rule.is_active)} className="p-1.5 text-white/30 hover:text-white transition" title={rule.is_active ? "Disable" : "Enable"}>
                    {rule.is_active ? <ToggleRight className="h-5 w-5 text-indigo-400" /> : <ToggleLeft className="h-5 w-5" />}
                  </button>
                  <button onClick={() => deleteRule(rule.id)} className="p-1.5 text-white/20 hover:text-red-400 transition rounded-lg hover:bg-red-500/10">
                    <Trash2 className="h-3.5 w-3.5" />
                  </button>
                </div>
              </div>
            )
          })}
        </div>
      )}

      {/* Log */}
      {logs.length > 0 && (
        <div className="rounded-xl border border-white/[0.06] bg-[#16161f] overflow-hidden">
          <div className="px-5 py-3.5 border-b border-white/[0.06]">
            <p className="text-sm font-semibold text-white">Follow-up Log</p>
          </div>
          <div className="divide-y divide-white/[0.04]">
            {logs.map((log) => (
              <div key={log.id} className="px-5 py-3.5 flex items-start gap-4">
                <div className={`flex h-8 w-8 shrink-0 items-center justify-center rounded-lg ${typeColors[log.type] ?? "text-white/40 bg-white/5"}`}>
                  <Bell className="h-3.5 w-3.5" />
                </div>
                <div className="flex-1 min-w-0">
                  <p className="text-sm font-medium text-white">{log.subject}</p>
                  {log.recipient_email && (
                    <p className="text-xs text-white/35 mt-0.5">{log.recipient_name} · {log.recipient_email}</p>
                  )}
                  <p className="text-xs text-white/25 mt-1 line-clamp-2">{log.message}</p>
                </div>
                <p className="shrink-0 text-xs text-white/25 mt-0.5">
                  {formatDistanceToNow(new Date(log.created_at), { addSuffix: true })}
                </p>
              </div>
            ))}
          </div>
        </div>
      )}
    </div>
  )
}