import { NextRequest, NextResponse } from 'next/server'
import { Pool } from 'pg'

const pool = new Pool({
  connectionString: process.env.DATABASE_URL || 'postgresql://breakpilot:breakpilot123@bp-core-postgres:5432/breakpilot_db',
})

/**
 * GET /api/sdk/v1/master-controls?action=list|detail|members
 */
export async function GET(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url)
    const action = searchParams.get('action') || 'list'

    if (action === 'list') {
      return handleList(searchParams)
    }
    if (action === 'detail') {
      return handleDetail(searchParams)
    }
    if (action === 'members') {
      return handleMembers(searchParams)
    }

    return NextResponse.json({ error: 'Unknown action' }, { status: 400 })
  } catch (e) {
    return NextResponse.json({ error: String(e) }, { status: 500 })
  }
}

async function handleList(params: URLSearchParams) {
  const search = params.get('search') || ''
  const minControls = parseInt(params.get('min_controls') || '0')
  const sortBy = params.get('sort') || 'total_controls'
  const order = params.get('order') || 'DESC'
  const limit = Math.min(parseInt(params.get('limit') || '100'), 500)
  const offset = parseInt(params.get('offset') || '0')

  const validSort = ['total_controls', 'canonical_name', 'created_at'].includes(sortBy) ? sortBy : 'total_controls'
  const validOrder = order === 'ASC' ? 'ASC' : 'DESC'

  let where = 'WHERE 1=1'
  const args: unknown[] = []
  let idx = 1

  if (search) {
    where += ` AND mc.canonical_name ILIKE $${idx}`
    args.push(`%${search}%`)
    idx++
  }
  if (minControls > 0) {
    where += ` AND mc.total_controls >= $${idx}`
    args.push(minControls)
    idx++
  }

  const countRes = await pool.query(
    `SELECT count(*) FROM compliance.master_controls mc ${where}`, args
  )
  const total = parseInt(countRes.rows[0].count)

  args.push(limit, offset)
  const res = await pool.query(
    `SELECT mc.id, mc.master_control_id, mc.canonical_name,
            mc.total_controls, mc.phases_covered, mc.phase_control_count
     FROM compliance.master_controls mc
     ${where}
     ORDER BY mc.${validSort} ${validOrder}
     LIMIT $${idx} OFFSET $${idx + 1}`,
    args
  )

  return NextResponse.json({
    total,
    limit,
    offset,
    master_controls: res.rows,
  })
}

async function handleDetail(params: URLSearchParams) {
  const id = params.get('id')
  if (!id) return NextResponse.json({ error: 'id required' }, { status: 400 })

  const res = await pool.query(
    `SELECT mc.id, mc.master_control_id, mc.canonical_name,
            mc.total_controls, mc.phases_covered, mc.phase_control_count
     FROM compliance.master_controls mc
     WHERE mc.master_control_id = $1 OR mc.id::text = $1`,
    [id]
  )

  if (res.rows.length === 0) {
    return NextResponse.json({ error: 'not found' }, { status: 404 })
  }

  return NextResponse.json({ master_control: res.rows[0] })
}

async function handleMembers(params: URLSearchParams) {
  const mcId = params.get('mc_id')
  if (!mcId) return NextResponse.json({ error: 'mc_id required' }, { status: 400 })

  const limit = Math.min(parseInt(params.get('limit') || '50'), 200)
  const offset = parseInt(params.get('offset') || '0')

  const res = await pool.query(
    `SELECT cc.control_id, cc.title, cc.objective, cc.severity,
            mcm.phase, mcm.action,
            COALESCE(pc.source_citation::jsonb->>'source', '') as regulation_source,
            COALESCE(pc.source_citation::jsonb->>'article', '') as regulation_article
     FROM compliance.master_control_members mcm
     JOIN compliance.canonical_controls cc ON cc.id = mcm.control_uuid
     LEFT JOIN compliance.canonical_controls pc ON pc.id = cc.parent_control_uuid
     WHERE mcm.master_control_uuid = (
       SELECT id FROM compliance.master_controls WHERE master_control_id = $1 OR id::text = $1 LIMIT 1
     )
     ORDER BY mcm.phase, cc.control_id
     LIMIT $2 OFFSET $3`,
    [mcId, limit, offset]
  )

  return NextResponse.json({
    mc_id: mcId,
    members: res.rows,
    count: res.rows.length,
  })
}