import { readFile } from 'fs/promises'
import { existsSync, readFileSync } from 'fs'
import { getActiveEnvPath, getActiveAuthPath } from '../../services/hermes/hermes-profile'
import { readConfigYaml, writeConfigYaml, fetchProviderModels, buildModelGroups, PROVIDER_ENV_MAP } from '../../services/config-helpers'
import { buildProviderModelMap, PROVIDER_PRESETS } from '../../shared/providers'
import { getCopilotModelsDetailed, resolveCopilotOAuthToken, type CopilotModelMeta } from '../../services/hermes/copilot-models'
import { readAppConfig, writeAppConfig, type ModelVisibilityRule } from '../../services/app-config'
import { getDb } from '../../db'
import { MODEL_CONTEXT_TABLE } from '../../db/hermes/schemas'

const PROVIDER_MODEL_CATALOG = buildProviderModelMap()

type ModelMeta = { preview?: boolean; disabled?: boolean }
type AvailableGroup = { provider: string; label: string; base_url: string; models: string[]; api_key: string; builtin?: boolean; model_meta?: Record<string, ModelMeta>; available_models?: string[] }
type ModelVisibility = Record<string, ModelVisibilityRule>

function uniqueStrings(values: unknown): string[] {
  if (!Array.isArray(values)) return []
  return Array.from(new Set(values.map(v => String(v || '').trim()).filter(Boolean)))
}

function normalizeModelVisibility(input: unknown): ModelVisibility {
  if (!input || typeof input !== 'object' || Array.isArray(input)) return {}
  const out: ModelVisibility = {}
  for (const [provider, rawRule] of Object.entries(input as Record<string, unknown>)) {
    const providerKey = String(provider || '').trim()
    if (!providerKey || !rawRule || typeof rawRule !== 'object' || Array.isArray(rawRule)) continue
    const rule = rawRule as { mode?: unknown; models?: unknown }
    const mode = rule.mode === 'include' ? 'include' : 'all'
    const models = uniqueStrings(rule.models)
    if (mode === 'include') {
      if (models.length > 0) out[providerKey] = { mode, models }
    } else {
      out[providerKey] = { mode: 'all', models: [] }
    }
  }
  return out
}

function filterModelsForProvider(provider: string, models: string[], visibility: ModelVisibility): string[] {
  const rule = visibility[provider]
  if (!rule || rule.mode !== 'include') return models
  const allowed = new Set(rule.models)
  const visible = models.filter(model => allowed.has(model))
  // If a stale hand-edited rule references models that are no longer present,
  // fail open so the provider remains recoverable from the Web UI.
  return visible.length > 0 ? visible : models
}

function applyModelVisibility(groups: AvailableGroup[], visibility: ModelVisibility): AvailableGroup[] {
  return groups
    .map(group => {
      const availableModels = group.available_models || group.models
      return {
        ...group,
        available_models: availableModels,
        models: filterModelsForProvider(group.provider, availableModels, visibility),
      }
    })
    .filter(group => group.models.length > 0)
}

function resolveVisibleDefault(defaultModel: string, defaultProvider: string, groups: AvailableGroup[]) {
  if (defaultModel) {
    const explicit = groups.find(group => group.provider === defaultProvider && group.models.includes(defaultModel))
    if (explicit) return { defaultModel, defaultProvider }
    const inferred = groups.find(group => group.models.includes(defaultModel))
    if (inferred) return { defaultModel, defaultProvider: inferred.provider }
  }
  const fallback = groups.find(group => group.models.length > 0)
  return { defaultModel: fallback?.models[0] || '', defaultProvider: fallback?.provider || '' }
}


// Copilot 授权检测：复用同一套 token 解析逻辑（含 ~/.config/github-copilot/apps.json
// 与 ghp_ PAT 跳过），与 getCopilotModels 行为一致，避免出现"模型能拉到却被判未授权"。
async function isCopilotAuthorized(envContent: string): Promise<boolean> {
  return !!(await resolveCopilotOAuthToken(envContent))
}

export async function getAvailable(ctx: any) {
  try {
    const config = await readConfigYaml()
    const modelSection = config.model
    let currentDefault = ''
    let currentDefaultProvider = ''
    if (typeof modelSection === 'object' && modelSection !== null) {
      currentDefault = String(modelSection.default || '').trim()
      currentDefaultProvider = String(modelSection.provider || '').trim()
      // When hermes CLI sets provider: custom, resolve to custom:name
      // by matching base_url + model against custom_providers
      if (currentDefaultProvider === 'custom' && currentDefault) {
        const cps = Array.isArray(config.custom_providers) ? config.custom_providers as any[] : []
        const match = cps.find(
          (cp: any) => cp.base_url?.replace(/\/+$/, '') === String(modelSection.base_url || '').replace(/\/+$/, '')
            && cp.model === currentDefault,
        )
        if (match) {
          currentDefaultProvider = `custom:${match.name.trim().toLowerCase().replace(/ /g, '-')}`
        }
      }
    } else if (typeof modelSection === 'string') {
      currentDefault = modelSection.trim()
    }

    const groups: AvailableGroup[] = []
    const seenProviders = new Set<string>()

    let envContent = ''
    try { envContent = await readFile(getActiveEnvPath(), 'utf-8') } catch { }

    const envHasValue = (key: string): boolean => {
      if (!key) return false
      const match = envContent.match(new RegExp(`^${key}\\s*=\\s*(.+)`, 'm'))
      return !!match && match[1].trim() !== '' && !match[1].trim().startsWith('#')
    }
    const envGetValue = (key: string): string => {
      if (!key) return ''
      const match = envContent.match(new RegExp(`^${key}\\s*=\\s*(.+)`, 'm'))
      return match?.[1]?.trim() || ''
    }
    const addGroup = (provider: string, label: string, base_url: string, models: string[], api_key: string, builtin?: boolean, model_meta?: Record<string, ModelMeta>) => {
      if (seenProviders.has(provider)) return
      seenProviders.add(provider)
      const availableModels = [...models]
      groups.push({ provider, label, base_url, models: availableModels, available_models: availableModels, api_key, ...(builtin ? { builtin: true } : {}), ...(model_meta ? { model_meta } : {}) })
    }

    const isOAuthAuthorized = (providerKey: string): boolean => {
      try {
        const authPath = getActiveAuthPath()
        if (!existsSync(authPath)) return false
        const auth = JSON.parse(readFileSync(authPath, 'utf-8'))
        const provider = auth.providers?.[providerKey]
        const pool = auth.credential_pool?.[providerKey]
        // Legacy OAuth providers are stored under providers.*; newer Hermes
        // credential pools store Codex-style OAuth entries under
        // credential_pool.*. Treat either shape as an authorized provider.
        return !!(
          provider?.tokens?.access_token ||
          provider?.access_token ||
          (Array.isArray(pool) && pool.some((entry: any) => entry?.access_token))
        )
      } catch { return false }
    }

    // 同一请求内复用 copilot 动态模型（getCopilotModelsDetailed 内部有 inflight + 缓存，
    // 这里再缓存到局部变量进一步减少分支）
    let copilotLiveModels: CopilotModelMeta[] | null = null
    const getCopilotLive = async (): Promise<CopilotModelMeta[]> => {
      if (copilotLiveModels !== null) return copilotLiveModels
      try { copilotLiveModels = await getCopilotModelsDetailed(envContent) }
      catch { copilotLiveModels = [] }
      return copilotLiveModels
    }

    // Copilot 显式 opt-in：即便能解析到 token，未通过 web-ui Add Provider 显式启用
    // 时也不返回。避免误把 VS Code/gh CLI 用户的全局凭证当作 hermes provider。
    const appConfig = await readAppConfig()
    const copilotEnabled = appConfig.copilotEnabled === true
    const modelVisibility = normalizeModelVisibility(appConfig.modelVisibility)

    // 兼容老用户：上一版本会"自动 fallback discovery"出 Copilot；升级后这些用户的
    // config.yaml 可能仍把 model.default 指向某个 copilot 模型。若此时 copilot 已不
    // 启用，把返回的 default 清掉，让前端兜底自动选剩余 provider 的第一个 model。
    if (!copilotEnabled && currentDefaultProvider.toLowerCase() === 'copilot') {
      currentDefault = ''
      currentDefaultProvider = ''
    }

    for (const [providerKey, envMapping] of Object.entries(PROVIDER_ENV_MAP)) {
      if (envMapping.api_key_env && !envHasValue(envMapping.api_key_env)) continue
      if (!envMapping.api_key_env) {
        if (providerKey === 'copilot') {
          if (!copilotEnabled) continue
          if (!(await isCopilotAuthorized(envContent))) continue
        } else if (!isOAuthAuthorized(providerKey)) {
          continue
        }
      }
      const preset = PROVIDER_PRESETS.find((p: any) => p.value === providerKey)
      const label = preset?.label || providerKey.replace(/^custom:/, '')
      let baseUrl = preset?.base_url || ''
      if (envMapping.base_url_env && envHasValue(envMapping.base_url_env)) {
        baseUrl = envGetValue(envMapping.base_url_env) || baseUrl
      }
      const catalogModels = PROVIDER_MODEL_CATALOG[providerKey]
      let modelsList: string[] = catalogModels && catalogModels.length > 0 ? [...catalogModels] : []
      let modelMeta: Record<string, { preview?: boolean; disabled?: boolean }> | undefined
      if (providerKey === 'copilot') {
        const live = await getCopilotLive()
        if (live.length > 0) {
          modelsList = live.map((m) => m.id)
          modelMeta = {}
          for (const m of live) {
            if (m.preview || m.disabled) {
              modelMeta[m.id] = {
                ...(m.preview ? { preview: true } : {}),
                ...(m.disabled ? { disabled: true } : {}),
              }
            }
          }
          if (Object.keys(modelMeta).length === 0) modelMeta = undefined
        }
      } else if (providerKey === 'openrouter' || providerKey === 'cliproxyapi') {
        // OpenRouter and local CLIProxyAPI expose dynamic OpenAI-compatible /models catalogs.
        if (envMapping.api_key_env) {
          const apiKey = envGetValue(envMapping.api_key_env)
          if (apiKey) {
            try {
              const fetched = await fetchProviderModels(baseUrl, apiKey, providerKey === 'openrouter')
              if (fetched.length > 0) modelsList = fetched
            } catch { /* ignore — leave empty, won't show */ }
          }
        }
      }
      if (modelsList.length > 0) {
        const apiKey = envMapping.api_key_env ? envGetValue(envMapping.api_key_env) : ''
        addGroup(providerKey, label, baseUrl, modelsList, apiKey, true, modelMeta)
      }
    }

    const customProviders = Array.isArray(config.custom_providers)
      ? config.custom_providers as Array<{ name: string; base_url: string; model: string; api_key?: string }>
      : []

    const customFetches = await Promise.allSettled(
      customProviders.map(async cp => {
        if (!cp.base_url) return null
        const providerKey = `custom:${cp.name.trim().toLowerCase().replace(/ /g, '-')}`
        const baseUrl = cp.base_url.replace(/\/+$/, '')
        const bareKey = cp.name.trim().toLowerCase().replace(/ /g, '-')
        const builtinPreset = PROVIDER_PRESETS.find(p => p.value === bareKey)
        let models = builtinPreset?.models?.length ? [...builtinPreset.models] : [cp.model]
        // Skip dynamic fetch for builtin presets — their model list is maintained in providers.ts
        if (!builtinPreset && cp.api_key) {
          try { const fetched = await fetchProviderModels(baseUrl, cp.api_key); if (fetched.length > 0) models = [...new Set([cp.model, ...fetched])] } catch { }
        }
        const label = builtinPreset?.label || cp.name
        const presetBaseUrl = builtinPreset?.base_url || ''
        return { providerKey, label, base_url: presetBaseUrl || baseUrl, models, api_key: cp.api_key || '', builtin: !!builtinPreset }
      }),
    )

    for (const result of customFetches) {
      if (result.status === 'fulfilled' && result.value) {
        const { providerKey, label, base_url, models, api_key: cpApiKey, builtin: cpBuiltin } = result.value as any
        addGroup(providerKey, label, base_url, models, cpApiKey, cpBuiltin)
      }
    }

    for (const g of groups) { g.models = Array.from(new Set(g.models)) }
    const visibleGroups = applyModelVisibility(groups, modelVisibility)
    const visibleDefault = resolveVisibleDefault(currentDefault, currentDefaultProvider, visibleGroups)

    // 动态拉一次 copilot 模型用于 allProviders 展示（同一请求复用缓存）
    // 未启用 Copilot 时跳过拉取，避免空跑网络请求。
    const liveCopilotModels = copilotEnabled ? await getCopilotLive() : []
    const liveCopilotIds = liveCopilotModels.map((m) => m.id)

    const allProvidersBase = PROVIDER_PRESETS.map((p: any) => ({
      provider: p.value,
      label: p.label,
      base_url: p.base_url,
      models: p.value === 'copilot' && liveCopilotIds.length > 0 ? liveCopilotIds : p.models,
    }))

    if (groups.length === 0) {
      const fallback = buildModelGroups(config)
      const fallbackGroups: AvailableGroup[] = fallback.groups.map(group => {
        const models = group.models.map(model => model.id)
        return {
          provider: group.provider,
          label: group.provider,
          base_url: '',
          models,
          available_models: models,
          api_key: '',
        }
      })
      const visibleFallbackGroups = applyModelVisibility(fallbackGroups, modelVisibility)
      const fallbackDefault = resolveVisibleDefault(fallback.default, currentDefaultProvider, visibleFallbackGroups)
      ctx.body = {
        default: fallbackDefault.defaultModel,
        default_provider: fallbackDefault.defaultProvider,
        groups: visibleFallbackGroups,
        allProviders: allProvidersBase,
        model_visibility: modelVisibility,
      }
      return
    }

    ctx.body = {
      default: visibleDefault.defaultModel,
      default_provider: visibleDefault.defaultProvider,
      groups: visibleGroups,
      allProviders: allProvidersBase,
      model_visibility: modelVisibility,
    }
  } catch (err: any) {
    ctx.status = 500
    ctx.body = { error: err.message }
  }
}

export async function getConfigModels(ctx: any) {
  try {
    const config = await readConfigYaml()
    ctx.body = buildModelGroups(config)
  } catch (err: any) {
    ctx.status = 500
    ctx.body = { error: err.message }
  }
}

export async function setConfigModel(ctx: any) {
  const { default: defaultModel, provider: reqProvider } = ctx.request.body as { default: string; provider?: string }
  if (!defaultModel) {
    ctx.status = 400
    ctx.body = { error: 'Missing default model' }
    return
  }
  try {
    const config = await readConfigYaml()
    config.model = {}
    config.model.default = defaultModel
    if (reqProvider) { config.model.provider = reqProvider }
    await writeConfigYaml(config)
    ctx.body = { success: true }
  } catch (err: any) {
    ctx.status = 500
    ctx.body = { error: err.message }
  }
}

/**
 * 设置模型上下文配置（UPSERT：存在则更新，不存在则插入）
 * 支持路径参数和查询参数两种方式
 */
export async function updateModelContext(ctx: any) {
  // 支持两种方式：
  // 1. 路径参数: /api/hermes/model-context/:provider/:model
  // 2. 查询参数: /api/hermes/model-context?provider=xxx&model=xxx
  let provider: string | undefined
  let model: string | undefined

  // 优先从路径参数获取
  if (ctx.params.provider && ctx.params.model) {
    provider = ctx.params.provider
    model = ctx.params.model
  } else {
    // 从查询参数获取
    const query = ctx.query as { provider?: string; model?: string }
    provider = query.provider
    model = query.model
  }

  // 如果没有参数，从请求体获取
  if (!provider || !model) {
    const body = ctx.request.body as { provider?: string; model?: string; context_limit?: number }
    provider = body.provider
    model = body.model
  }

  const { context_limit } = ctx.request.body as { context_limit: number }

  if (!provider || !model || !context_limit) {
    ctx.status = 400
    ctx.body = { error: 'Missing required fields: provider, model, context_limit' }
    return
  }

  if (typeof context_limit !== 'number' || context_limit <= 0) {
    ctx.status = 400
    ctx.body = { error: 'Context limit must be a positive number' }
    return
  }

  try {
    const db = getDb()
    if (!db) {
      ctx.status = 500
      ctx.body = { error: 'Database not available' }
      return
    }

    // 使用 REPLACE 实现 UPSERT：存在则替换，不存在则插入
    db.prepare(
      `REPLACE INTO ${MODEL_CONTEXT_TABLE} (provider, model, context_limit) VALUES (?, ?, ?)`
    ).run(provider, model, context_limit)

    // 查询并返回更新后的数据
    const row = db.prepare(
      `SELECT id, provider, model, context_limit FROM ${MODEL_CONTEXT_TABLE} WHERE provider = ? AND model = ?`
    ).get(provider, model) as { id: number; provider: string; model: string; context_limit: number }

    ctx.body = {
      success: true,
      data: row
    }
  } catch (err: any) {
    ctx.status = 500
    ctx.body = { error: err.message }
  }
}

/**
 * 查询模型上下文配置
 */
export async function getModelContext(ctx: any) {
  // 支持两种方式：
  // 1. 路径参数: /api/hermes/model-context/:provider/:model
  // 2. 查询参数: /api/hermes/model-context?provider=xxx&model=xxx
  let provider: string | undefined
  let model: string | undefined

  // 优先从路径参数获取
  if (ctx.params.provider && ctx.params.model) {
    provider = ctx.params.provider
    model = ctx.params.model
  } else {
    // 从查询参数获取
    const query = ctx.query as { provider?: string; model?: string }
    provider = query.provider
    model = query.model
  }

  if (!provider || !model) {
    ctx.status = 400
    ctx.body = { error: 'Missing provider or model parameter' }
    return
  }

  try {
    const db = getDb()
    if (!db) {
      ctx.status = 500
      ctx.body = { error: 'Database not available' }
      return
    }

    const row = db.prepare(
      `SELECT id, provider, model, context_limit FROM ${MODEL_CONTEXT_TABLE} WHERE provider = ? AND model = ?`
    ).get(provider, model) as { id: number; provider: string; model: string; context_limit: number } | undefined

    if (!row) {
      ctx.status = 404
      ctx.body = { error: 'Model context not found' }
      return
    }

    ctx.body = { data: { ...row, limit: row.context_limit } }
  } catch (err: any) {
    ctx.status = 500
    ctx.body = { error: err.message }
  }
}


export async function setModelVisibility(ctx: any) {
  const { provider, mode, models } = ctx.request.body as { provider?: string; mode?: string; models?: string[] }
  const providerKey = String(provider || '').trim()
  if (!providerKey) {
    ctx.status = 400
    ctx.body = { error: 'Missing provider' }
    return
  }
  if (mode !== 'all' && mode !== 'include') {
    ctx.status = 400
    ctx.body = { error: 'Invalid visibility mode' }
    return
  }
  const selectedModels = uniqueStrings(models)
  if (mode === 'include' && selectedModels.length === 0) {
    ctx.status = 400
    ctx.body = { error: 'Select at least one model' }
    return
  }

  try {
    const appConfig = await readAppConfig()
    const modelVisibility = normalizeModelVisibility(appConfig.modelVisibility)
    if (mode === 'all') {
      delete modelVisibility[providerKey]
    } else {
      modelVisibility[providerKey] = { mode: 'include', models: selectedModels }
    }
    const saved = await writeAppConfig({ modelVisibility })
    ctx.body = { success: true, model_visibility: normalizeModelVisibility(saved.modelVisibility) }
  } catch (err: any) {
    ctx.status = 500
    ctx.body = { error: err.message }
  }
}