import { NextRequest, NextResponse } from 'next/server'
import { getDatabase, db_helpers, Message } from '@/lib/db'
import { runOpenClaw } from '@/lib/command'
import { getAllGatewaySessions } from '@/lib/sessions'
import { eventBus } from '@/lib/event-bus'
import { requireRole } from '@/lib/auth'
import { logger } from '@/lib/logger'
import { scanForInjection, sanitizeForPrompt } from '@/lib/injection-guard'
import { callOpenClawGateway } from '@/lib/openclaw-gateway'
import { resolveCoordinatorDeliveryTarget } from '@/lib/coordinator-routing'

type ForwardInfo = {
  attempted: boolean
  delivered: boolean
  reason?: string
  session?: string
  runId?: string
}

type ToolEvent = {
  name: string
  input?: string
  output?: string
  status?: string
}

type ChatAttachmentInput = {
  name?: string
  type?: string
  dataUrl?: string
}

const COORDINATOR_AGENT =
  String(process.env.MC_COORDINATOR_AGENT || process.env.NEXT_PUBLIC_COORDINATOR_AGENT || 'coordinator').trim() ||
  'coordinator'

function parseGatewayJson(raw: string): any | null {
  const trimmed = String(raw || '').trim()
  if (!trimmed) return null
  const start = trimmed.indexOf('{')
  const end = trimmed.lastIndexOf('}')
  if (start < 0 || end < start) return null
  try {
    return JSON.parse(trimmed.slice(start, end + 1))
  } catch {
    return null
  }
}

function toGatewayAttachments(value: unknown): Array<{ type: 'image'; mimeType: string; fileName?: string; content: string }> | undefined {
  if (!Array.isArray(value)) return undefined

  const attachments = value.flatMap((entry) => {
    const file = entry as ChatAttachmentInput
    if (!file || typeof file !== 'object' || typeof file.dataUrl !== 'string') return []
    const match = /^data:([^;]+);base64,(.+)$/.exec(file.dataUrl)
    if (!match) return []
    if (!match[1].startsWith('image/')) return []
    return [{
      type: 'image' as const,
      mimeType: match[1],
      fileName: typeof file.name === 'string' ? file.name : undefined,
      content: match[2],
    }]
  })

  return attachments.length > 0 ? attachments : undefined
}

function safeParseMetadata(raw: string | null | undefined): any | null {
  if (!raw) return null
  try {
    return JSON.parse(raw)
  } catch {
    return null
  }
}

function createChatReply(
  db: ReturnType<typeof getDatabase>,
  workspaceId: number,
  conversationId: string,
  fromAgent: string,
  toAgent: string,
  content: string,
  messageType: 'text' | 'status' | 'tool_call' = 'status',
  metadata: Record<string, any> | null = null
) {
  const replyInsert = db
    .prepare(`
      INSERT INTO messages (conversation_id, from_agent, to_agent, content, message_type, metadata, workspace_id)
      VALUES (?, ?, ?, ?, ?, ?, ?)
    `)
    .run(
      conversationId,
      fromAgent,
      toAgent,
      content,
      messageType,
      metadata ? JSON.stringify(metadata) : null,
      workspaceId
    )

  const row = db
    .prepare('SELECT * FROM messages WHERE id = ? AND workspace_id = ?')
    .get(replyInsert.lastInsertRowid, workspaceId) as Message

  eventBus.broadcast('chat.message', {
    ...row,
    metadata: safeParseMetadata(row.metadata),
  })
}

function extractReplyText(waitPayload: any): string | null {
  if (!waitPayload || typeof waitPayload !== 'object') return null

  const directCandidates = [
    waitPayload.text,
    waitPayload.message,
    waitPayload.response,
    waitPayload.output,
    waitPayload.result,
  ]
  for (const value of directCandidates) {
    if (typeof value === 'string' && value.trim()) return value.trim()
  }

  if (typeof waitPayload.output === 'object' && waitPayload.output) {
    const nested = [
      waitPayload.output.text,
      waitPayload.output.message,
      waitPayload.output.content,
    ]
    for (const value of nested) {
      if (typeof value === 'string' && value.trim()) return value.trim()
    }
  }

  if (Array.isArray(waitPayload.output)) {
    const parts: string[] = []
    for (const item of waitPayload.output) {
      if (!item || typeof item !== 'object') continue
      if (typeof item.text === 'string' && item.text.trim()) parts.push(item.text.trim())
      if (item.type === 'message' && Array.isArray(item.content)) {
        for (const block of item.content) {
          if (!block || typeof block !== 'object') continue
          const blockType = String(block.type || '')
          if ((blockType === 'text' || blockType === 'output_text' || blockType === 'input_text') && typeof block.text === 'string' && block.text.trim()) {
            parts.push(block.text.trim())
          }
        }
      }
    }
    if (parts.length > 0) return parts.join('\n').slice(0, 8000)
  }

  return null
}

function normalizeToolEvent(raw: any): ToolEvent | null {
  if (!raw || typeof raw !== 'object') return null
  const name = String(raw.name || raw.tool || raw.toolName || raw.function || raw.call || '').trim()
  if (!name) return null

  const inputRaw = raw.input ?? raw.args ?? raw.arguments ?? raw.params
  const outputRaw = raw.output ?? raw.result ?? raw.response
  const statusRaw =
    raw.status ??
    (raw.isError === true ? 'error' : undefined) ??
    (raw.ok === false ? 'error' : undefined) ??
    (raw.success === true ? 'ok' : undefined)

  const input =
    typeof inputRaw === 'string'
      ? inputRaw.slice(0, 2000)
      : inputRaw !== undefined
        ? JSON.stringify(inputRaw).slice(0, 2000)
        : undefined
  const output =
    typeof outputRaw === 'string'
      ? outputRaw.slice(0, 4000)
      : outputRaw !== undefined
        ? JSON.stringify(outputRaw).slice(0, 4000)
        : undefined
  const status = statusRaw !== undefined ? String(statusRaw).slice(0, 60) : undefined
  return { name, input, output, status }
}

function extractToolEvents(waitPayload: any): ToolEvent[] {
  if (!waitPayload || typeof waitPayload !== 'object') return []

  const candidates = [
    waitPayload.toolCalls,
    waitPayload.tools,
    waitPayload.calls,
    waitPayload.events,
    waitPayload.output?.toolCalls,
    waitPayload.output?.tools,
    waitPayload.output?.events,
  ]

  const events: ToolEvent[] = []
  for (const list of candidates) {
    if (!Array.isArray(list)) continue
    for (const item of list) {
      const evt = normalizeToolEvent(item)
      if (evt) events.push(evt)
      if (events.length >= 20) return events
    }
  }

  // OpenAI Responses-style output array
  if (Array.isArray(waitPayload.output)) {
    for (const item of waitPayload.output) {
      if (!item || typeof item !== 'object') continue
      const itemType = String(item.type || '').toLowerCase()
      if (itemType === 'function_call' || itemType === 'tool_call') {
        const evt = normalizeToolEvent({
          name: item.name || item.tool_name || item.toolName,
          arguments: item.arguments || item.input,
          output: item.output || item.result,
          status: item.status,
        })
        if (evt) events.push(evt)
      } else if (itemType === 'message' && Array.isArray(item.content)) {
        for (const block of item.content) {
          const blockType = String(block?.type || '').toLowerCase()
          if (blockType === 'tool_use' || blockType === 'tool_call' || blockType === 'function_call') {
            const evt = normalizeToolEvent(block)
            if (evt) events.push(evt)
          }
        }
      }
      if (events.length >= 20) return events
    }
  }

  return events
}

/**
 * GET /api/chat/messages - List messages with filters
 * Query params: conversation_id, from_agent, to_agent, limit, offset, since
 */
export async function GET(request: NextRequest) {
  const auth = requireRole(request, 'viewer')
  if ('error' in auth) return NextResponse.json({ error: auth.error }, { status: auth.status })

  try {
    const db = getDatabase()
    const workspaceId = auth.user.workspace_id ?? 1
    const { searchParams } = new URL(request.url)

    const conversation_id = searchParams.get('conversation_id')
    const from_agent = searchParams.get('from_agent')
    const to_agent = searchParams.get('to_agent')
    const limit = Math.min(parseInt(searchParams.get('limit') || '50'), 200)
    const offset = parseInt(searchParams.get('offset') || '0')
    const since = searchParams.get('since')

    let query = 'SELECT * FROM messages WHERE workspace_id = ?'
    const params: any[] = [workspaceId]

    if (conversation_id) {
      query += ' AND conversation_id = ?'
      params.push(conversation_id)
    }

    if (from_agent) {
      query += ' AND from_agent = ?'
      params.push(from_agent)
    }

    if (to_agent) {
      query += ' AND to_agent = ?'
      params.push(to_agent)
    }

    if (since) {
      query += ' AND created_at > ?'
      params.push(parseInt(since))
    }

    query += ' ORDER BY created_at ASC LIMIT ? OFFSET ?'
    params.push(limit, offset)

    const messages = db.prepare(query).all(...params) as Message[]

    const parsed = messages.map((msg) => ({
      ...msg,
      metadata: safeParseMetadata(msg.metadata),
    }))

    // Get total count for pagination
    let countQuery = 'SELECT COUNT(*) as total FROM messages WHERE workspace_id = ?'
    const countParams: any[] = [workspaceId]
    if (conversation_id) {
      countQuery += ' AND conversation_id = ?'
      countParams.push(conversation_id)
    }
    if (from_agent) {
      countQuery += ' AND from_agent = ?'
      countParams.push(from_agent)
    }
    if (to_agent) {
      countQuery += ' AND to_agent = ?'
      countParams.push(to_agent)
    }
    if (since) {
      countQuery += ' AND created_at > ?'
      countParams.push(parseInt(since))
    }
    const countRow = db.prepare(countQuery).get(...countParams) as { total: number }

    return NextResponse.json({ messages: parsed, total: countRow.total, page: Math.floor(offset / limit) + 1, limit })
  } catch (error) {
    logger.error({ err: error }, 'GET /api/chat/messages error')
    return NextResponse.json({ error: 'Failed to fetch messages' }, { status: 500 })
  }
}

/**
 * POST /api/chat/messages - Send a new message
 * Body: { to, content, message_type, conversation_id, metadata }
 * Sender identity is always resolved server-side from authenticated user.
 */
export async function POST(request: NextRequest) {
  const auth = requireRole(request, 'operator')
  if ('error' in auth) return NextResponse.json({ error: auth.error }, { status: auth.status })

  try {
    const db = getDatabase()
    const workspaceId = auth.user.workspace_id ?? 1
    const body = await request.json()

    const requestedFrom = typeof body.from === 'string' ? body.from.trim() : ''
    const isCoordinatorOverride = requestedFrom.toLowerCase() === COORDINATOR_AGENT.toLowerCase()
    const from = isCoordinatorOverride
      ? COORDINATOR_AGENT
      : (auth.user.display_name || auth.user.username || 'system')
    const to = body.to ? (body.to as string).trim() : null
    const content = (body.content || '').trim()
    const message_type = body.message_type || 'text'
    const conversation_id = body.conversation_id || `conv_${Date.now()}`
    const metadata = body.metadata || null

    if (!content) {
      return NextResponse.json(
        { error: '"content" is required' },
        { status: 400 }
      )
    }

    // Scan content for injection when it will be forwarded to an agent
    if (body.forward && to) {
      const injectionReport = scanForInjection(content, { context: 'prompt' })
      if (!injectionReport.safe) {
        const criticals = injectionReport.matches.filter(m => m.severity === 'critical')
        if (criticals.length > 0) {
          logger.warn({ to, rules: criticals.map(m => m.rule) }, 'Blocked chat message: injection detected')
          return NextResponse.json(
            { error: 'Message blocked: potentially unsafe content detected', injection: criticals.map(m => ({ rule: m.rule, description: m.description })) },
            { status: 422 }
          )
        }
      }
    }

    const stmt = db.prepare(`
      INSERT INTO messages (conversation_id, from_agent, to_agent, content, message_type, metadata, workspace_id)
      VALUES (?, ?, ?, ?, ?, ?, ?)
    `)

    const result = stmt.run(
      conversation_id,
      from,
      to,
      content,
      message_type,
      metadata ? JSON.stringify(metadata) : null,
      workspaceId
    )

    const messageId = result.lastInsertRowid as number

    let forwardInfo: ForwardInfo | null = null

    // Log activity
    db_helpers.logActivity(
      'chat_message',
      'message',
      messageId,
      from,
      `Sent ${message_type} message${to ? ` to ${to}` : ' (broadcast)'}`,
      { conversation_id, to, message_type },
      workspaceId
    )

    // Create notification for recipient if specified
    if (to) {
      db_helpers.createNotification(
        to,
        'chat_message',
        `Message from ${from}`,
        content.substring(0, 200) + (content.length > 200 ? '...' : ''),
        'message',
        messageId,
        workspaceId
      )

      // Optionally forward to agent via gateway
      if (body.forward) {
        forwardInfo = { attempted: true, delivered: false }

        const agent = db
          .prepare('SELECT * FROM agents WHERE lower(name) = lower(?) AND workspace_id = ?')
          .get(to, workspaceId) as any

        const explicitSessionKey = typeof body.sessionKey === 'string' && body.sessionKey
          ? body.sessionKey
          : null
        const sessions = getAllGatewaySessions()
        const isCoordinatorSend = String(to).toLowerCase() === COORDINATOR_AGENT.toLowerCase()
        const allAgents = isCoordinatorSend
          ? (db
              .prepare('SELECT name, session_key, config FROM agents WHERE workspace_id = ?')
              .all(workspaceId) as Array<{ name: string; session_key?: string | null; config?: string | null }>)
          : []
        const configuredCoordinatorTarget = isCoordinatorSend
          ? (db
              .prepare("SELECT value FROM settings WHERE key = 'chat.coordinator_target_agent'")
              .get() as { value?: string } | undefined)?.value || null
          : null

        const coordinatorResolution = resolveCoordinatorDeliveryTarget({
          to: String(to),
          coordinatorAgent: COORDINATOR_AGENT,
          directAgent: agent
            ? {
                name: String(agent.name || to),
                session_key: typeof agent.session_key === 'string' ? agent.session_key : null,
                config: typeof agent.config === 'string' ? agent.config : null,
              }
            : null,
          allAgents,
          sessions,
          explicitSessionKey,
          configuredCoordinatorTarget,
        })

        // Use explicit session key from caller if provided, then DB, then on-disk lookup
        let sessionKey: string | null = coordinatorResolution.sessionKey

        // Fallback: derive session from on-disk gateway session stores
        if (!sessionKey) {
          const match = sessions.find(
            (s) =>
              s.agent.toLowerCase() === String(to).toLowerCase() ||
              s.agent.toLowerCase() === coordinatorResolution.deliveryName.toLowerCase() ||
              s.agent.toLowerCase() === String(coordinatorResolution.openclawAgentId || '').toLowerCase()
          )
          sessionKey = match?.key || match?.sessionId || null
        }

        // Prefer configured openclawId when present, fallback to normalized name
        let openclawAgentId: string | null = coordinatorResolution.openclawAgentId

        if (!sessionKey && !openclawAgentId) {
          forwardInfo.reason = 'no_active_session'

          // For coordinator messages, emit an immediate visible status reply
          if (typeof conversation_id === 'string' && conversation_id.startsWith('coord:')) {
            try {
                createChatReply(
                  db,
                  workspaceId,
                  conversation_id,
                  COORDINATOR_AGENT,
                  from,
                  'I received your message, but my live coordinator session is offline right now. Start/restore the coordinator session and retry.',
                  'status',
                  { status: 'offline', reason: 'no_active_session' }
                )
            } catch (e) {
              logger.error({ err: e }, 'Failed to create offline status reply')
            }
          }
        } else {
          try {
            const idempotencyKey = `mc-${messageId}-${Date.now()}`

            if (sessionKey) {
              const acceptedPayload = await callOpenClawGateway<any>(
                'chat.send',
                {
                  sessionKey,
                  message: content,
                  idempotencyKey,
                  deliver: false,
                  attachments: toGatewayAttachments(body.attachments),
                },
                12000,
              )
              const status = String(acceptedPayload?.status || '').toLowerCase()
              forwardInfo.delivered = status === 'started' || status === 'ok' || status === 'in_flight'
              forwardInfo.session = sessionKey
              if (typeof acceptedPayload?.runId === 'string' && acceptedPayload.runId) {
                forwardInfo.runId = acceptedPayload.runId
              }
            } else {
              const invokeParams: any = {
                message: `Message from ${from}: ${content}`,
                idempotencyKey,
                deliver: false,
              }
              invokeParams.agentId = openclawAgentId

              const invokeResult = await runOpenClaw(
                [
                  'gateway',
                  'call',
                  'agent',
                  '--timeout',
                  '10000',
                  '--params',
                  JSON.stringify(invokeParams),
                  '--json',
                ],
                { timeoutMs: 12000 }
              )
              const acceptedPayload = parseGatewayJson(invokeResult.stdout)
              forwardInfo.delivered = true
              forwardInfo.session = openclawAgentId || undefined
              if (typeof acceptedPayload?.runId === 'string' && acceptedPayload.runId) {
                forwardInfo.runId = acceptedPayload.runId
              }
            }
          } catch (err) {
            // OpenClaw may return accepted JSON on stdout but still emit a late stderr warning.
            // Treat accepted runs as successful delivery.
            const maybeStdout = String((err as any)?.stdout || '')
            const acceptedPayload = parseGatewayJson(maybeStdout)
            if (maybeStdout.includes('"status": "accepted"') || maybeStdout.includes('"status":"accepted"')) {
              forwardInfo.delivered = true
              forwardInfo.session = sessionKey || openclawAgentId || undefined
              if (typeof acceptedPayload?.runId === 'string' && acceptedPayload.runId) {
                forwardInfo.runId = acceptedPayload.runId
              }
            } else {
              forwardInfo.reason = 'gateway_send_failed'
              logger.error({ err }, 'Failed to forward message via gateway')

              // For coordinator messages, emit visible status when send fails
              if (typeof conversation_id === 'string' && conversation_id.startsWith('coord:')) {
                try {
                  createChatReply(
                    db,
                    workspaceId,
                    conversation_id,
                    COORDINATOR_AGENT,
                    from,
                    'I received your message, but delivery to the live coordinator runtime failed. Please restart the coordinator/gateway session and retry.',
                    'status',
                    { status: 'delivery_failed', reason: 'gateway_send_failed' }
                  )
                } catch (e) {
                  logger.error({ err: e }, 'Failed to create gateway failure status reply')
                }
              }
            }
          }

          // Coordinator mode should always show visible coordinator feedback in thread.
          if (
            typeof conversation_id === 'string' &&
            conversation_id.startsWith('coord:') &&
            forwardInfo.delivered
          ) {
            try {
              createChatReply(
                db,
                workspaceId,
                conversation_id,
                COORDINATOR_AGENT,
                from,
                'Received. I am coordinating downstream agents now.',
                'status',
                { status: 'accepted', runId: forwardInfo.runId || null }
              )
            } catch (e) {
              logger.error({ err: e }, 'Failed to create accepted status reply')
            }

            // Best effort: wait briefly and surface completion/error feedback.
            if (forwardInfo.runId) {
              try {
                const waitResult = await runOpenClaw(
                  [
                    'gateway',
                    'call',
                    'agent.wait',
                    '--timeout',
                    '8000',
                    '--params',
                    JSON.stringify({ runId: forwardInfo.runId, timeoutMs: 6000 }),
                    '--json',
                  ],
                  { timeoutMs: 9000 }
                )

                const waitPayload = parseGatewayJson(waitResult.stdout)
                const waitStatus = String(waitPayload?.status || '').toLowerCase()
                const toolEvents = extractToolEvents(waitPayload)

                if (toolEvents.length > 0) {
                  for (const evt of toolEvents) {
                    createChatReply(
                      db,
                      workspaceId,
                      conversation_id,
                      COORDINATOR_AGENT,
                      from,
                      evt.name,
                      'tool_call',
                      {
                        event: 'tool_call',
                        toolName: evt.name,
                        input: evt.input || null,
                        output: evt.output || null,
                        status: evt.status || null,
                        runId: forwardInfo.runId || null,
                      }
                    )
                  }
                }

                if (waitStatus === 'error') {
                  const reason =
                    typeof waitPayload?.error === 'string'
                      ? waitPayload.error
                      : 'Unknown runtime error'
                  createChatReply(
                    db,
                    workspaceId,
                    conversation_id,
                    COORDINATOR_AGENT,
                    from,
                    `I received your message, but execution failed: ${reason}`,
                    'status',
                    { status: 'error', runId: forwardInfo.runId }
                  )
                } else if (waitStatus === 'timeout') {
                  createChatReply(
                    db,
                    workspaceId,
                    conversation_id,
                    COORDINATOR_AGENT,
                    from,
                    'I received your message and I am still processing it. I will post results as soon as execution completes.',
                    'status',
                    { status: 'processing', runId: forwardInfo.runId }
                  )
                } else {
                  const replyText = extractReplyText(waitPayload)
                  if (replyText) {
                    createChatReply(
                      db,
                      workspaceId,
                      conversation_id,
                      COORDINATOR_AGENT,
                      from,
                      replyText,
                      'text',
                      { status: waitStatus || 'completed', runId: forwardInfo.runId }
                    )
                  } else {
                    createChatReply(
                      db,
                      workspaceId,
                      conversation_id,
                      COORDINATOR_AGENT,
                      from,
                      'Execution accepted and completed. No textual response payload was returned by the runtime.',
                      'status',
                      { status: waitStatus || 'completed', runId: forwardInfo.runId }
                    )
                  }
                }
              } catch (waitErr) {
                const maybeWaitStdout = String((waitErr as any)?.stdout || '')
                const maybeWaitStderr = String((waitErr as any)?.stderr || '')
                const waitPayload = parseGatewayJson(maybeWaitStdout)
                const reason =
                  typeof waitPayload?.error === 'string'
                    ? waitPayload.error
                    : (maybeWaitStderr || maybeWaitStdout || 'Unable to read completion status from coordinator runtime.').trim()

                createChatReply(
                  db,
                  workspaceId,
                  conversation_id,
                  COORDINATOR_AGENT,
                  from,
                  `I received your message, but I could not retrieve completion output yet: ${reason}`,
                  'status',
                  { status: 'unknown', runId: forwardInfo.runId }
                )
              }
            }
          }
        }
      }
    }

    const created = db.prepare('SELECT * FROM messages WHERE id = ? AND workspace_id = ?').get(messageId, workspaceId) as Message
    const parsedMessage = {
      ...created,
      metadata: {
        ...(safeParseMetadata(created.metadata) || {}),
        forwardInfo: forwardInfo || undefined,
      },
    }

    // Broadcast to SSE clients
    eventBus.broadcast('chat.message', parsedMessage)

    return NextResponse.json({ message: parsedMessage, forward: forwardInfo }, { status: 201 })
  } catch (error) {
    logger.error({ err: error }, 'POST /api/chat/messages error')
    return NextResponse.json({ error: 'Failed to send message' }, { status: 500 })
  }
}