//
// Copyright © 2022 Hardcore Engineering Inc.
//
// Licensed under the Eclipse Public License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License. You may
// obtain a copy of the License at https://www.eclipse.org/legal/epl-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//
// See the License for the specific language governing permissions and
// limitations under the License.
//

import core, {
  Branding,
  coreId,
  DOMAIN_BENCHMARK,
  DOMAIN_MIGRATION,
  DOMAIN_MODEL,
  DOMAIN_TRANSIENT,
  DOMAIN_TX,
  groupByArray,
  Hierarchy,
  MeasureContext,
  MigrationState,
  ModelDb,
  systemAccountEmail,
  toWorkspaceString,
  Tx,
  TxOperations,
  WorkspaceId,
  WorkspaceIdWithUrl,
  type Client,
  type Doc,
  type Ref,
  type WithLookup
} from '@hcengineering/core'
import { consoleModelLogger, MigrateOperation, ModelLogger, tryMigrate } from '@hcengineering/model'
import { DomainIndexHelperImpl, Pipeline, StorageAdapter, type DbAdapter } from '@hcengineering/server-core'
import { InitScript, WorkspaceInitializer } from './initializer'
import toolPlugin from './plugin'
import { MigrateClientImpl } from './upgrade'

import { getMetadata, PlatformError, unknownError } from '@hcengineering/platform'
import { generateToken } from '@hcengineering/server-token'
import fs from 'fs'
import * as yaml from 'js-yaml'
import path from 'path'

export * from './connect'
export * from './plugin'
export { toolPlugin as default }

export class FileModelLogger implements ModelLogger {
  handle: fs.WriteStream
  constructor (readonly file: string) {
    fs.mkdirSync(path.dirname(this.file), { recursive: true })

    this.handle = fs.createWriteStream(this.file, { flags: 'a' })
  }

  log (msg: string, data: any): void {
    this.handle.write(msg + ' : ' + JSON.stringify(data) + '\n')
  }

  error (msg: string, data: any): void {
    this.handle.write(msg + ': ' + JSON.stringify(data) + '\n')
  }

  close (): void {
    this.handle.close()
  }
}

/**
 * @public
 */
export function prepareTools (rawTxes: Tx[]): {
  dbUrl: string
  txes: Tx[]
} {
  const dbUrl = process.env.DB_URL
  if (dbUrl === undefined) {
    console.error('please provide db url.')
    process.exit(1)
  }

  return {
    dbUrl,
    txes: JSON.parse(JSON.stringify(rawTxes)) as Tx[]
  }
}

/**
 * @public
 */
export async function initModel (
  ctx: MeasureContext,
  workspaceId: WorkspaceId,
  rawTxes: Tx[],
  adapter: DbAdapter,
  storageAdapter: StorageAdapter,
  logger: ModelLogger = consoleModelLogger,
  progress: (value: number) => Promise<void>
): Promise<void> {
  const { txes } = prepareTools(rawTxes)
  if (txes.some((tx) => tx.objectSpace !== core.space.Model)) {
    throw Error('Model txes must target only core.space.Model')
  }

  try {
    logger.log('creating database...', workspaceId)
    await adapter.upload(ctx, DOMAIN_TX, [
      {
        _class: core.class.Tx,
        _id: 'first-tx' as Ref<Doc>,
        modifiedBy: core.account.System,
        modifiedOn: Date.now(),
        space: core.space.DerivedTx
      }
    ])

    await progress(30)

    logger.log('creating data...', { workspaceId })

    await progress(60)

    logger.log('create storage bucket', { workspaceId })

    await storageAdapter.make(ctx, workspaceId)
    await progress(100)
  } catch (err: any) {
    ctx.error('Failed to create workspace', { error: err })
    throw err
  } finally {
    await adapter.close()
  }
}

export async function updateModel (
  ctx: MeasureContext,
  workspaceId: WorkspaceId,
  migrateOperations: [string, MigrateOperation][],
  connection: TxOperations,
  pipeline: Pipeline,
  logger: ModelLogger = consoleModelLogger,
  progress: (value: number) => Promise<void>
): Promise<void> {
  logger.log('connecting to transactor', { workspaceId })

  const states = await connection.findAll<MigrationState>(core.class.MigrationState, {})
  const sts = Array.from(groupByArray(states, (it) => it.plugin).entries())

  const _toSet = (vals: WithLookup<MigrationState>[]): Set<string> => {
    return new Set(vals.map((q) => q.state))
  }

  const migrateState = new Map<string, Set<string>>(sts.map((it) => [it[0], _toSet(it[1])]))

  try {
    let i = 0
    for (const op of migrateOperations) {
      const st = Date.now()
      await op[1].upgrade(migrateState, async () => connection as any, logger)
      const tdelta = Date.now() - st
      if (tdelta > 0) {
        logger.log('Create', { name: op[0], time: tdelta })
      }
      i++
      await progress((((100 / migrateOperations.length) * i) / 100) * 100)
    }
    await progress(100)
  } catch (e: any) {
    logger.error('error', { error: e })
    throw e
  }
}

/**
 * @public
 */
export async function initializeWorkspace (
  ctx: MeasureContext,
  branding: Branding | null,
  wsUrl: WorkspaceIdWithUrl,
  storageAdapter: StorageAdapter,
  client: TxOperations,
  logger: ModelLogger = consoleModelLogger,
  progress: (value: number) => Promise<void>
): Promise<void> {
  const initWS = branding?.initWorkspace ?? getMetadata(toolPlugin.metadata.InitWorkspace)
  const scriptUrl = getMetadata(toolPlugin.metadata.InitScriptURL)
  ctx.info('Init script details', { scriptUrl, initWS })
  if (initWS === undefined || scriptUrl === undefined) return
  try {
    // `https://raw.githubusercontent.com/hcengineering/init/main/script.yaml`
    const req = await fetch(scriptUrl)
    const text = await req.text()
    const scripts = yaml.load(text) as any as InitScript[]
    let script: InitScript | undefined
    if (initWS !== undefined) {
      script = scripts.find((it) => it.name === initWS)
    }
    if (script === undefined) {
      script = scripts.find((it) => it.default)
    }
    if (script === undefined) {
      return
    }

    const initializer = new WorkspaceInitializer(ctx, storageAdapter, wsUrl, client)
    await initializer.processScript(script, logger, progress)
  } catch (err: any) {
    ctx.error('Failed to initialize workspace', { error: err })
    throw err
  }
}

/**
 * @public
 */
export async function upgradeModel (
  ctx: MeasureContext,
  transactorUrl: string,
  workspaceId: WorkspaceIdWithUrl,
  txes: Tx[],
  pipeline: Pipeline,
  connection: Client,
  storageAdapter: StorageAdapter,
  migrateOperations: [string, MigrateOperation][],
  logger: ModelLogger = consoleModelLogger,
  progress: (value: number) => Promise<void>,
  updateIndexes: 'perform' | 'skip' | 'disable' = 'skip'
): Promise<Tx[]> {
  if (txes.some((tx) => tx.objectSpace !== core.space.Model)) {
    throw Error('Model txes must target only core.space.Model')
  }

  const newModelRes = await ctx.with('load-model', {}, (ctx) => pipeline.loadModel(ctx, 0))
  const newModel = Array.isArray(newModelRes) ? newModelRes : newModelRes.transactions

  const { hierarchy, modelDb, model } = await buildModel(ctx, newModel)
  const { migrateClient: preMigrateClient } = await prepareMigrationClient(
    pipeline,
    hierarchy,
    modelDb,
    logger,
    storageAdapter,
    workspaceId
  )

  await progress(0)
  await ctx.with('pre-migrate', {}, async (ctx) => {
    let i = 0

    for (const op of migrateOperations) {
      if (op[1].preMigrate === undefined) {
        continue
      }
      const preMigrate = op[1].preMigrate

      const t = Date.now()
      try {
        await ctx.with(op[0], {}, async (ctx) => {
          await preMigrate(preMigrateClient, logger)
        })
      } catch (err: any) {
        logger.error(`error during pre-migrate: ${op[0]} ${err.message}`, err)
        throw err
      }
      logger.log('pre-migrate:', { workspaceId: workspaceId.name, operation: op[0], time: Date.now() - t })
      await progress(((100 / migrateOperations.length) * i * 10) / 100)
      i++
    }
  })

  const { migrateClient, migrateState } = await prepareMigrationClient(
    pipeline,
    hierarchy,
    modelDb,
    logger,
    storageAdapter,
    workspaceId
  )

  const upgradeIndexes = async (): Promise<void> => {
    ctx.info('Migrate indexes')
    // Create update indexes
    await createUpdateIndexes(
      ctx,
      hierarchy,
      modelDb,
      pipeline,
      async (value) => {
        await progress(90 + (Math.min(value, 100) / 100) * 10)
      },
      workspaceId
    )
  }
  if (updateIndexes === 'perform') {
    await upgradeIndexes()
  }

  await ctx.with('migrate', {}, async (ctx) => {
    let i = 0
    for (const op of migrateOperations) {
      try {
        const t = Date.now()
        await ctx.with(op[0], {}, async () => {
          await op[1].migrate(migrateClient, logger)
        })
        const tdelta = Date.now() - t
        if (tdelta > 0) {
          logger.log('migrate:', { workspaceId: workspaceId.name, operation: op[0], time: Date.now() - t })
        }
      } catch (err: any) {
        logger.error(`error during migrate: ${op[0]} ${err.message}`, err)
        throw err
      }
      await progress(20 + ((100 / migrateOperations.length) * i * 20) / 100)
      i++
    }

    if (updateIndexes === 'skip') {
      await tryMigrate(migrateClient, coreId, [
        {
          state: 'indexes-v5',
          func: upgradeIndexes
        }
      ])
    }
  })

  logger.log('Apply upgrade operations', { workspaceId: workspaceId.name })

  await ctx.with('upgrade', {}, async (ctx) => {
    let i = 0
    for (const op of migrateOperations) {
      const t = Date.now()
      await ctx.with(op[0], {}, async () => {
        await op[1].upgrade(migrateState, async () => connection, logger)
      })
      const tdelta = Date.now() - t
      if (tdelta > 0) {
        logger.log('upgrade:', { operation: op[0], time: tdelta, workspaceId: workspaceId.name })
      }
      await progress(60 + ((100 / migrateOperations.length) * i * 30) / 100)
      i++
    }
  })

  // We need to send reboot for workspace
  ctx.info('send force close', { workspace: workspaceId.name, transactorUrl })
  const serverEndpoint = transactorUrl.replaceAll('wss://', 'https://').replace('ws://', 'http://')
  const token = generateToken(systemAccountEmail, workspaceId, { admin: 'true' })
  try {
    await fetch(
      serverEndpoint + `/api/v1/manage?token=${token}&operation=force-close&wsId=${toWorkspaceString(workspaceId)}`,
      {
        method: 'PUT'
      }
    )
  } catch (err: any) {
    // Ignore error if transactor is not yet ready
  }
  return model
}

async function prepareMigrationClient (
  pipeline: Pipeline,
  hierarchy: Hierarchy,
  model: ModelDb,
  logger: ModelLogger,
  storageAdapter: StorageAdapter,
  workspaceId: WorkspaceId
): Promise<{
    migrateClient: MigrateClientImpl
    migrateState: Map<string, Set<string>>
  }> {
  const migrateClient = new MigrateClientImpl(pipeline, hierarchy, model, logger, storageAdapter, workspaceId)
  const states = await migrateClient.find<MigrationState>(DOMAIN_MIGRATION, { _class: core.class.MigrationState })
  const sts = Array.from(groupByArray(states, (it) => it.plugin).entries())

  const _toSet = (vals: WithLookup<MigrationState>[]): Set<string> => {
    return new Set(vals.map((q) => q.state))
  }

  const migrateState = new Map<string, Set<string>>(sts.map((it) => [it[0], _toSet(it[1])]))
  // const migrateState = new Map(sts.map((it) => [it[0], new Set(it[1].map((q) => q.state))]))
  migrateClient.migrateState = migrateState

  return { migrateClient, migrateState }
}

export async function buildModel (
  ctx: MeasureContext,
  model: Tx[]
): Promise<{ hierarchy: Hierarchy, modelDb: ModelDb, model: Tx[] }> {
  const hierarchy = new Hierarchy()
  const modelDb = new ModelDb(hierarchy)

  ctx.withSync('build local model', {}, () => {
    for (const tx of model ?? []) {
      try {
        hierarchy.tx(tx)
      } catch (err: any) {}
    }
    modelDb.addTxes(ctx, model, false)
  })
  return { hierarchy, modelDb, model: model ?? [] }
}

async function createUpdateIndexes (
  ctx: MeasureContext,
  hierarchy: Hierarchy,
  model: ModelDb,
  pipeline: Pipeline,
  progress: (value: number) => Promise<void>,
  workspaceId: WorkspaceId
): Promise<void> {
  const domainHelper = new DomainIndexHelperImpl(ctx, hierarchy, model, workspaceId)
  let completed = 0
  const allDomains = hierarchy.domains()
  for (const domain of allDomains) {
    if (domain === DOMAIN_MODEL || domain === DOMAIN_TRANSIENT || domain === DOMAIN_BENCHMARK) {
      continue
    }
    const adapter = pipeline.context.adapterManager?.getAdapter(domain, false)
    if (adapter === undefined) {
      throw new PlatformError(unknownError(`Adapter for domain ${domain} not found`))
    }
    const dbHelper = adapter.helper?.()

    if (dbHelper !== undefined) {
      await domainHelper.checkDomain(ctx, domain, await dbHelper.estimatedCount(domain), dbHelper)
    }
    completed++
    await progress((100 / allDomains.length) * completed)
  }
}