"use client"

import { useState, useRef, useEffect } from "react"
import { Button } from "@/components/ui/button"
import { Input } from "@/components/ui/input"
import { Plus, MessageSquare, Trash2, X, Pencil, Check, X as XIcon } from "lucide-react"
import type { ChatSession } from "./types"

interface ChatSidebarProps {
  chatHistory: ChatSession[]
  currentSessionId: string | null
  showHistory: boolean
  onLoadSession: (sessionId: string) => void
  onDeleteSession: (sessionId: string) => void
  onRenameSession: (sessionId: string, newTitle: string) => void
  onCreateSession: () => void
  onCloseHistory: () => void
}

export function ChatSidebar({
  chatHistory,
  currentSessionId,
  showHistory,
  onLoadSession,
  onDeleteSession,
  onRenameSession,
  onCreateSession,
  onCloseHistory
}: ChatSidebarProps) {
  const [editingSessionId, setEditingSessionId] = useState<string | null>(null)
  const [editTitle, setEditTitle] = useState("")
  const editInputRef = useRef<HTMLInputElement>(null)

  useEffect(() => {
    if (editingSessionId && editInputRef.current) {
      editInputRef.current.focus()
    }
  }, [editingSessionId])

  const startEditing = (session: ChatSession, e: React.MouseEvent) => {
    e.stopPropagation()
    setEditingSessionId(session.id)
    setEditTitle(session.title || "")
  }

  const cancelEditing = (e?: React.MouseEvent) => {
    e?.stopPropagation()
    setEditingSessionId(null)
    setEditTitle("")
  }

  const saveTitle = (sessionId: string, e?: React.MouseEvent) => {
    e?.stopPropagation()
    if (editTitle.trim()) {
      onRenameSession(sessionId, editTitle.trim())
    }
    setEditingSessionId(null)
    setEditTitle("")
  }

  const handleKeyDown = (e: React.KeyboardEvent, sessionId: string) => {
    if (e.key === "Enter") {
      saveTitle(sessionId)
    } else if (e.key === "Escape") {
      cancelEditing()
    }
  }
  // Prevent body scroll when mobile sidebar is open
  useEffect(() => {
    if (showHistory) {
      document.body.style.overflow = "hidden"
    } else {
      document.body.style.overflow = "unset"
    }
    return () => {
      document.body.style.overflow = "unset"
    }
  }, [showHistory])

  return (
    <>
      {/* Desktop Sidebar */}
      <div className="hidden md:flex w-72 border-r border-white/5 bg-black/20 backdrop-blur-xl flex-col transition-all duration-300 ease-in-out h-full">
        <div className="p-4 border-b border-white/5 flex-shrink-0">
          <div className="flex items-center justify-between">
            <div>
              <p className="text-xs uppercase tracking-widest text-muted-foreground">Sessions</p>
              <h3 className="font-semibold text-sm">Chat History</h3>
            </div>
            <Button variant="ghost" size="sm" onClick={onCreateSession} className="h-8 w-8 rounded-full">
              <Plus className="w-3 h-3" />
            </Button>
          </div>
        </div>
        <div className="p-3 space-y-2 flex-1 overflow-y-auto [&::-webkit-scrollbar]:hidden [-ms-overflow-style:none] [scrollbar-width:none]">
          {chatHistory.map((session) => (
            <div key={session.id} className="flex items-center space-x-2 p-1 group min-w-0">
              <div
                className={`flex-1 flex items-center justify-between text-left h-auto px-3 py-2 text-xs transition-all duration-200 rounded-2xl border border-transparent group-hover:border-white/10 min-w-0 cursor-pointer ${currentSessionId === session.id ? "bg-secondary text-secondary-foreground" : "hover:bg-accent hover:text-accent-foreground"}`}
                onClick={() => onLoadSession(session.id)}
              >
                <div className="flex items-center w-full min-w-0">
                  <div className="flex h-7 w-7 items-center justify-center rounded-xl bg-white/10 mr-3 flex-shrink-0">
                    <MessageSquare className="w-3.5 h-3.5" />
                  </div>
                  <div className="flex-1 min-w-0 overflow-hidden">
                    {editingSessionId === session.id ? (
                      <div className="flex items-center gap-1" onClick={(e) => e.stopPropagation()}>
                        <Input
                          ref={editInputRef}
                          value={editTitle}
                          onChange={(e) => setEditTitle(e.target.value)}
                          onKeyDown={(e) => handleKeyDown(e, session.id)}
                          className="h-6 text-xs py-0 px-1 bg-background/50"
                        />
                        <Button
                          variant="ghost"
                          size="sm"
                          className="h-6 w-6 p-0 hover:bg-green-500/20 hover:text-green-500"
                          onClick={(e) => saveTitle(session.id, e)}
                        >
                          <Check className="w-3 h-3" />
                        </Button>
                        <Button
                          variant="ghost"
                          size="sm"
                          className="h-6 w-6 p-0 hover:bg-red-500/20 hover:text-red-500"
                          onClick={cancelEditing}
                        >
                          <XIcon className="w-3 h-3" />
                        </Button>
                      </div>
                    ) : (
                      <>
                        <div 
                          className="font-medium truncate text-xs block"
                          title={session.title || `Chat ${session.id.slice(-6)}`}
                        >
                          {session.title || `Chat ${session.id.slice(-6)}`}
                        </div>
                        <div className="text-[11px] text-muted-foreground truncate">{session.message_count} messages</div>
                      </>
                    )}
                  </div>
                </div>
              </div>
              <div className="flex flex-col gap-1 opacity-0 group-hover:opacity-100 transition-opacity duration-200">
                <Button
                  variant="ghost"
                  size="sm"
                  className="text-muted-foreground hover:text-primary h-6 w-6 rounded-full p-0"
                  onClick={(e) => startEditing(session, e)}
                >
                  <Pencil className="w-3 h-3" />
                </Button>
                <Button
                  variant="ghost"
                  size="sm"
                  className="text-muted-foreground hover:text-destructive h-6 w-6 rounded-full p-0"
                  onClick={(e) => {
                    e.stopPropagation()
                    onDeleteSession(session.id)
                  }}
                >
                  <Trash2 className="w-3 h-3" />
                </Button>
              </div>
            </div>
          ))}
        </div>
      </div>

      {/* Mobile Sidebar Overlay */}
      {showHistory && (
        <div className="md:hidden fixed inset-0 z-[60] bg-black/70 backdrop-blur-sm" onClick={onCloseHistory}>
          <div className="absolute left-0 top-0 h-full w-[85%] max-w-sm bg-background border-r border-white/10 shadow-2xl z-[61] flex flex-col" onClick={(e) => e.stopPropagation()}>
            <div className="p-3 md:p-4 border-b border-white/10 flex-shrink-0">
              <div className="flex items-center justify-between mb-2">
                <h3 className="font-semibold text-sm md:text-base">Chat History</h3>
                <Button variant="ghost" size="sm" className="h-9 w-9 rounded-full" onClick={onCloseHistory}>
                  <X className="w-4 h-4" />
                </Button>
              </div>
              <Button
                variant="outline"
                size="sm"
                className="w-full h-9 md:h-10 rounded-xl text-xs md:text-sm"
                onClick={() => {
                  onCreateSession()
                  onCloseHistory()
                }}
              >
                <Plus className="w-4 h-4 mr-2" />
                New Chat
              </Button>
            </div>
            <div className="p-2 md:p-3 space-y-1 flex-1 overflow-y-auto [&::-webkit-scrollbar]:hidden [-ms-overflow-style:none] [scrollbar-width:none]">
              {chatHistory.map((session) => (
                <div key={session.id} className="flex items-center space-x-1.5 md:space-x-2 p-1 group min-w-0">
                  <Button
                    variant={currentSessionId === session.id ? "secondary" : "ghost"}
                    className="flex-1 justify-start text-left h-auto p-2 md:p-3 min-w-0 min-h-[44px]"
                    onClick={() => {
                      onLoadSession(session.id)
                      onCloseHistory()
                    }}
                  >
                    <MessageSquare className="w-3.5 h-3.5 md:w-4 md:h-4 mr-1.5 md:mr-2 flex-shrink-0" />
                    <div className="flex-1 min-w-0 overflow-hidden">
                      <div 
                        className="font-medium truncate block text-xs md:text-sm"
                        title={session.title || `Chat ${session.id.slice(-8)}`}
                      >
                        {session.title || `Chat ${session.id.slice(-8)}`}
                      </div>
                      <div className="text-[10px] md:text-xs text-muted-foreground truncate">{session.message_count} messages</div>
                    </div>
                  </Button>
                  <Button
                    variant="ghost"
                    size="sm"
                    className="text-muted-foreground hover:text-destructive h-9 w-9 md:h-10 md:w-10 rounded-full flex-shrink-0"
                    onClick={(e) => {
                      e.stopPropagation()
                      onDeleteSession(session.id)
                    }}
                  >
                    <Trash2 className="w-3.5 h-3.5 md:w-4 md:h-4" />
                  </Button>
                </div>
              ))}
            </div>
          </div>
        </div>
      )}
    </>
  )
}