import { getDb } from './db'

interface ScanConfig {
  schedule: string
  enabled: boolean
  lastScanAt: number | null
}

function getSetting(key: string): string | null {
  const db = getDb()
  const row = db
    .prepare('SELECT value FROM app_settings WHERE key = ?')
    .get(key) as { value: string } | undefined
  return row?.value ?? null
}

function setSetting(key: string, value: string): void {
  const db = getDb()
  db.prepare('INSERT OR REPLACE INTO app_settings (key, value) VALUES (?, ?)').run(key, value)
}

export function getScanConfig(): ScanConfig {
  const schedule = getSetting('scan_schedule') ?? '0 * * * *'
  const enabled = getSetting('scan_enabled') !== 'false'
  const lastRanRaw = getSetting('scan_last_ran')
  const lastScanAt =
    lastRanRaw && lastRanRaw.length > 0 ? parseInt(lastRanRaw, 10) : null
  return { schedule, enabled, lastScanAt }
}

export function updateScanConfig(schedule: string, enabled: boolean): void {
  setSetting('scan_schedule', schedule)
  setSetting('scan_enabled', enabled ? 'true' : 'false')
}

export function setScanLastRan(ts: number): void {
  setSetting('scan_last_ran', String(ts))
}

// ─── AI Settings ─────────────────────────────────────────────────────────────

const DEFAULT_PROMPT_DESCRIBE =
  'Focus on the visual content, subjects, setting, and mood. Do not speculate about context outside the image. Do not preface the description with any phrases like "This image shows" or "This image features". Return only the description text with no additional commentary.'
const DEFAULT_PROMPT_TAGGER = ''
const DEFAULT_PROMPT_EXTRACT =
  'Be mindful of different colors of text that may indicate different speakers or emphasis.'
const DEFAULT_PROMPT_TRANSLATE = 'Return ONLY the translated text with no additional commentary.'

export type OcrMode = 'hybrid' | 'tesseract' | 'llm'

export interface AiConfig {
  endpoint: string
  model: string
  modelTagging: string
  modelDescribe: string
  modelExtract: string
  modelTranslate: string
  enabled: boolean
  promptDescribe: string
  promptTagger: string
  promptExtract: string
  promptTranslate: string
  maxTokensTag: number
  maxTokensDescribe: number
  maxTokensExtract: number
  maxTokensTranslate: number
  ocrMode: OcrMode
  ocrLanguages: string
  ocrConfidenceThreshold: number
}

export function getAiConfig(): AiConfig {
  const endpoint = getSetting('ai_endpoint') ?? ''
  const model = getSetting('ai_model') ?? ''
  const modelTagging = getSetting('ai_model_tagging') ?? ''
  const modelDescribe = getSetting('ai_model_describe') ?? ''
  const modelExtract = getSetting('ai_model_extract') ?? ''
  const modelTranslate = getSetting('ai_model_translate') ?? ''
  const enabled = getSetting('ai_enabled') === 'true'
  const promptDescribeRaw = getSetting('ai_prompt_describe')
  const promptDescribe = promptDescribeRaw !== null ? promptDescribeRaw : DEFAULT_PROMPT_DESCRIBE
  const promptTaggerRaw = getSetting('ai_prompt_tagger')
  const promptTagger = promptTaggerRaw !== null ? promptTaggerRaw : DEFAULT_PROMPT_TAGGER
  const promptExtractRaw = getSetting('ai_prompt_extract')
  const promptExtract = promptExtractRaw !== null ? promptExtractRaw : DEFAULT_PROMPT_EXTRACT
  const promptTranslateRaw = getSetting('ai_prompt_translate')
  const promptTranslate = promptTranslateRaw !== null ? promptTranslateRaw : DEFAULT_PROMPT_TRANSLATE
  const maxTokensTag = parseInt(getSetting('ai_max_tokens_tag') ?? '8192', 10) || 8192
  const maxTokensDescribe = parseInt(getSetting('ai_max_tokens_describe') ?? '8192', 10) || 8192
  const maxTokensExtract = parseInt(getSetting('ai_max_tokens_extract') ?? '8192', 10) || 8192
  const maxTokensTranslate = parseInt(getSetting('ai_max_tokens_translate') ?? '8192', 10) || 8192
  const rawOcrMode = getSetting('ai_ocr_mode') ?? 'hybrid'
  const ocrMode: OcrMode = rawOcrMode === 'tesseract' || rawOcrMode === 'llm' ? rawOcrMode : 'hybrid'
  const ocrLanguages = getSetting('ai_ocr_languages') ?? 'eng'
  const ocrConfidenceThreshold = parseInt(getSetting('ai_ocr_confidence_threshold') ?? '70', 10) || 70
  return {
    endpoint, model, modelTagging, modelDescribe, modelExtract, modelTranslate, enabled,
    promptDescribe, promptTagger, promptExtract, promptTranslate,
    maxTokensTag, maxTokensDescribe, maxTokensExtract, maxTokensTranslate,
    ocrMode, ocrLanguages, ocrConfidenceThreshold,
  }
}

export function updateAiConfig(
  endpoint: string,
  model: string,
  enabled: boolean,
  modelTagging?: string,
  modelDescribe?: string,
  modelExtract?: string,
  modelTranslate?: string,
  promptDescribe?: string,
  promptTagger?: string,
  promptExtract?: string,
  promptTranslate?: string,
  maxTokensTag?: number,
  maxTokensDescribe?: number,
  maxTokensExtract?: number,
  maxTokensTranslate?: number,
  ocrMode?: OcrMode,
  ocrLanguages?: string,
  ocrConfidenceThreshold?: number,
): void {
  setSetting('ai_endpoint', endpoint)
  setSetting('ai_model', model)
  setSetting('ai_enabled', enabled ? 'true' : 'false')
  if (modelTagging !== undefined) setSetting('ai_model_tagging', modelTagging)
  if (modelDescribe !== undefined) setSetting('ai_model_describe', modelDescribe)
  if (modelExtract !== undefined) setSetting('ai_model_extract', modelExtract)
  if (modelTranslate !== undefined) setSetting('ai_model_translate', modelTranslate)
  if (promptDescribe !== undefined) setSetting('ai_prompt_describe', promptDescribe)
  if (promptTagger !== undefined) setSetting('ai_prompt_tagger', promptTagger)
  if (promptExtract !== undefined) setSetting('ai_prompt_extract', promptExtract)
  if (promptTranslate !== undefined) setSetting('ai_prompt_translate', promptTranslate)
  if (maxTokensTag !== undefined) setSetting('ai_max_tokens_tag', String(Math.max(1, Math.floor(maxTokensTag))))
  if (maxTokensDescribe !== undefined) setSetting('ai_max_tokens_describe', String(Math.max(1, Math.floor(maxTokensDescribe))))
  if (maxTokensExtract !== undefined) setSetting('ai_max_tokens_extract', String(Math.max(1, Math.floor(maxTokensExtract))))
  if (maxTokensTranslate !== undefined) setSetting('ai_max_tokens_translate', String(Math.max(1, Math.floor(maxTokensTranslate))))
  if (ocrMode !== undefined) setSetting('ai_ocr_mode', ocrMode)
  if (ocrLanguages !== undefined) setSetting('ai_ocr_languages', ocrLanguages.trim() || 'eng')
  if (ocrConfidenceThreshold !== undefined) setSetting('ai_ocr_confidence_threshold', String(Math.max(0, Math.min(100, Math.floor(ocrConfidenceThreshold)))))
}

export function getPreferredLanguage(): string {
  return getSetting('preferred_language') ?? 'English'
}

export function setPreferredLanguage(language: string): void {
  setSetting('preferred_language', language)
}

// ─── Per-library AI overrides ─────────────────────────────────────────────────

export interface LibraryAiOverrides {
  modelTagging: string
  modelDescribe: string
  modelExtract: string
  modelTranslate: string
  promptDescribe: string
  promptTagger: string
  promptExtract: string
  promptTranslate: string
  maxTokensTag: number | null
  maxTokensDescribe: number | null
  maxTokensExtract: number | null
  maxTokensTranslate: number | null
}

interface LibraryAiSettingsRow {
  model_tagging: string | null
  model_describe: string | null
  model_extract: string | null
  model_translate: string | null
  prompt_describe: string | null
  prompt_tagger: string | null
  prompt_extract: string | null
  prompt_translate: string | null
  max_tokens_tag: number | null
  max_tokens_describe: number | null
  max_tokens_extract: number | null
  max_tokens_translate: number | null
}

export function getLibraryAiOverrides(libraryId: string): LibraryAiOverrides {
  const db = getDb()
  const row = db
    .prepare('SELECT * FROM library_ai_settings WHERE library_id = ?')
    .get(libraryId) as LibraryAiSettingsRow | undefined
  return {
    modelTagging: row?.model_tagging ?? '',
    modelDescribe: row?.model_describe ?? '',
    modelExtract: row?.model_extract ?? '',
    modelTranslate: row?.model_translate ?? '',
    promptDescribe: row?.prompt_describe ?? '',
    promptTagger: row?.prompt_tagger ?? '',
    promptExtract: row?.prompt_extract ?? '',
    promptTranslate: row?.prompt_translate ?? '',
    maxTokensTag: row?.max_tokens_tag ?? null,
    maxTokensDescribe: row?.max_tokens_describe ?? null,
    maxTokensExtract: row?.max_tokens_extract ?? null,
    maxTokensTranslate: row?.max_tokens_translate ?? null,
  }
}

export function setLibraryAiOverrides(libraryId: string, overrides: Partial<LibraryAiOverrides>): void {
  const db = getDb()
  // Ensure a row exists
  db.prepare(
    'INSERT OR IGNORE INTO library_ai_settings (library_id) VALUES (?)'
  ).run(libraryId)

  const stringFields: Record<string, string | undefined> = {
    model_tagging: overrides.modelTagging,
    model_describe: overrides.modelDescribe,
    model_extract: overrides.modelExtract,
    model_translate: overrides.modelTranslate,
    prompt_describe: overrides.promptDescribe,
    prompt_tagger: overrides.promptTagger,
    prompt_extract: overrides.promptExtract,
    prompt_translate: overrides.promptTranslate,
  }

  for (const [col, val] of Object.entries(stringFields)) {
    if (val !== undefined) {
      db.prepare(`UPDATE library_ai_settings SET ${col} = ? WHERE library_id = ?`).run(
        val === '' ? null : val,
        libraryId,
      )
    }
  }

  const numberFields: Record<string, number | null | undefined> = {
    max_tokens_tag: overrides.maxTokensTag,
    max_tokens_describe: overrides.maxTokensDescribe,
    max_tokens_extract: overrides.maxTokensExtract,
    max_tokens_translate: overrides.maxTokensTranslate,
  }

  for (const [col, val] of Object.entries(numberFields)) {
    if (val !== undefined) {
      db.prepare(`UPDATE library_ai_settings SET ${col} = ? WHERE library_id = ?`).run(
        val === null ? null : Math.max(1, Math.floor(val)),
        libraryId,
      )
    }
  }
}

export function getEffectiveAiConfig(libraryId: string): AiConfig {
  const global = getAiConfig()
  const overrides = getLibraryAiOverrides(libraryId)
  return {
    endpoint: global.endpoint,
    model: global.model,
    enabled: global.enabled,
    modelTagging: overrides.modelTagging || global.modelTagging,
    modelDescribe: overrides.modelDescribe || global.modelDescribe,
    modelExtract: overrides.modelExtract || global.modelExtract,
    modelTranslate: overrides.modelTranslate || global.modelTranslate,
    promptDescribe: overrides.promptDescribe || global.promptDescribe,
    promptTagger: overrides.promptTagger || global.promptTagger,
    promptExtract: overrides.promptExtract || global.promptExtract,
    promptTranslate: overrides.promptTranslate || global.promptTranslate,
    maxTokensTag: overrides.maxTokensTag ?? global.maxTokensTag,
    maxTokensDescribe: overrides.maxTokensDescribe ?? global.maxTokensDescribe,
    maxTokensExtract: overrides.maxTokensExtract ?? global.maxTokensExtract,
    maxTokensTranslate: overrides.maxTokensTranslate ?? global.maxTokensTranslate,
    ocrMode: global.ocrMode,
    ocrLanguages: global.ocrLanguages,
    ocrConfidenceThreshold: global.ocrConfidenceThreshold,
  }
}

// ─── AI Max Retries ──────────────────────────────────────────────────────────

export function getAiMaxRetries(): number {
  const raw = getSetting('ai_max_retries')
  const parsed = parseInt(raw ?? '3', 10)
  return Number.isFinite(parsed) && parsed >= 0 ? parsed : 3
}

export function setAiMaxRetries(n: number): void {
  setSetting('ai_max_retries', String(Math.max(0, Math.floor(n))))
}