import type { FastifyPluginAsync } from 'fastify'
import { repos } from '@evofw/db'
import {
  createPolicySetBodySchema,
  patchPolicySetBodySchema,
  agentIdsBodySchema,
} from '@evofw/shared'
import { AppError } from '../plugins/error-handler.js'
import type { AppConfig } from '../config.js'
import { auditMutation } from '../services/audit.js'
import { mapPolicySet, mapPolicySets } from '../services/row-mappers.js'

export const policySetsRoutes: FastifyPluginAsync<{ config: AppConfig }> = async (
  app,
  opts,
) => {
  const { config } = opts

  app.get('/policy-sets', async () => ({
    items: mapPolicySets(app.db, repos.listPolicySets(app.db)),
  }))

  app.get<{ Params: { id: string } }>('/policy-sets/:id', async (req) => {
    const s = repos.getPolicySet(app.db, req.params.id)
    if (!s) throw new AppError('NOT_FOUND', 'Policy set not found', 404)
    return {
      ...mapPolicySet(s, app.db),
      agent_ids: repos.listAgentIdsForSet(app.db, s.id),
    }
  })

  app.post('/policy-sets', async (req) => {
    const body = createPolicySetBodySchema.parse(req.body)
    const row = repos.insertPolicySet(app.db, {
      id: crypto.randomUUID(),
      name: body.name.trim(),
      description: body.description ?? null,
      enabled: body.enabled === false ? 0 : 1,
      policyMode: 'blacklist',
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
    })
    auditMutation(app, config, req, {
      action: 'policy_set.create',
      targetType: 'app_resource',
      targetId: row!.id,
      summary: `Создан набор политик: ${row!.name}`,
      details: { set_id: row!.id },
    })
    return mapPolicySet(row!, app.db)
  })

  app.patch<{ Params: { id: string } }>('/policy-sets/:id', async (req) => {
    const body = patchPolicySetBodySchema.parse(req.body)
    const s = repos.getPolicySet(app.db, req.params.id)
    if (!s) throw new AppError('NOT_FOUND', 'Policy set not found', 404)
    const updated = repos.updatePolicySet(app.db, s.id, {
      name: body.name?.trim(),
      description: body.description,
      enabled: body.enabled === undefined ? undefined : body.enabled ? 1 : 0,
    })
    if (body.enabled !== undefined) {
      repos.bumpAgentsForSet(app.db, s.id)
    }
    auditMutation(app, config, req, {
      action: 'policy_set.update',
      targetType: 'app_resource',
      targetId: s.id,
      summary: `Обновлён набор политик: ${updated!.name}`,
      details: {
        set_id: s.id,
        enabled: body.enabled,
        name: body.name,
      },
    })
    return mapPolicySet(updated!, app.db)
  })

  app.delete<{ Params: { id: string } }>('/policy-sets/:id', async (req) => {
    const s = repos.getPolicySet(app.db, req.params.id)
    try {
      const agentIds = repos.listAgentIdsForSet(app.db, req.params.id)
      repos.deletePolicySet(app.db, req.params.id)
      for (const id of agentIds) repos.bumpAgentGeneration(app.db, id)
      if (s) {
        auditMutation(app, config, req, {
          action: 'policy_set.delete',
          severity: 'warning',
          targetType: 'app_resource',
          targetId: s.id,
          summary: `Набор политик удалён: ${s.name}`,
          details: { set_id: s.id, agents_affected: agentIds.length },
        })
      }
    } catch (err) {
      throw new AppError(
        'VALIDATION_ERROR',
        err instanceof Error ? err.message : String(err),
        400,
      )
    }
    return { ok: true }
  })

  /**
   * Replace which agents have this set assigned: listed agents gain the set
   * (other assignments preserved), unlisted agents lose it.
   */
  app.put<{ Params: { id: string } }>(
    '/policy-sets/:id/agents',
    async (req) => {
      const set = repos.getPolicySet(app.db, req.params.id)
      if (!set) throw new AppError('NOT_FOUND', 'Policy set not found', 404)
      const body = agentIdsBodySchema.parse(req.body)

      const target = new Set(body.agent_ids)
      for (const agentId of body.agent_ids) {
        if (!repos.getAgent(app.db, agentId)) {
          throw new AppError('NOT_FOUND', `Agent not found: ${agentId}`, 404)
        }
      }

      const current = repos.listAgentIdsForSet(app.db, set.id)
      const toAdd = body.agent_ids.filter((id) => !current.includes(id))
      const toRemove = current.filter((id) => !target.has(id))

      const applyAssignment = (agentId: string, withSet: boolean) => {
        const others = repos
          .listSetsForAgent(app.db, agentId)
          .map((s) => s.setId)
          .filter((id) => id !== set.id)
        const next = withSet ? [...others, set.id] : others
        repos.setAgentPolicySets(app.db, agentId, next)
      }

      app.sqlite.transaction(() => {
        for (const agentId of toAdd) applyAssignment(agentId, true)
        for (const agentId of toRemove) applyAssignment(agentId, false)
      })()

      auditMutation(app, config, req, {
        action: 'policy_set.agents.update',
        targetType: 'app_resource',
        targetId: set.id,
        summary: `Назначение набора ${set.name} обновлено`,
        details: {
          set_id: set.id,
          added: toAdd,
          removed: toRemove,
        },
      })
      return {
        agent_ids: repos.listAgentIdsForSet(app.db, set.id),
        added: toAdd,
        removed: toRemove,
      }
    },
  )
}