/**
 * Regenerates src/catalog.ts from the published Command Code CLI package.
 *
 * The CLI ships the authoritative model reference (ids, context windows,
 * reasoning efforts, advertised rates) and its bundle carries the
 * input-modality and max-output metadata that the Provider API does not
 * expose. Run `npm run sync:catalog` after Command Code publishes a new CLI
 * release; review the printed diff before committing the regenerated file.
 *
 * Usage:
 *   node scripts/sync-catalog.mjs [--version 1.54.0] [--check]
 */

import { execFile } from "node:child_process"
import { mkdtemp, mkdir, readFile, rm, writeFile } from "node:fs/promises"
import { tmpdir } from "node:os"
import { dirname, join } from "node:path"
import { fileURLToPath } from "node:url"
import { promisify } from "node:util"

const execFileAsync = promisify(execFile)
const projectRoot = join(dirname(fileURLToPath(import.meta.url)), "..")
const catalogPath = join(projectRoot, "src", "catalog.ts")
const modelsReferencePath = "package/dist/bundled/command-code-knowledge/reference/models.md"
const cliBundlePath = "package/dist/cli.mjs"
const validEfforts = ["minimal", "low", "medium", "high", "xhigh", "max"]

function parseArguments(argv) {
  const options = { version: undefined, check: false }
  for (let index = 0; index < argv.length; index += 1) {
    const argument = argv[index]
    if (argument === "--check") options.check = true
    else if (argument === "--version") {
      options.version = argv[index + 1]
      index += 1
    } else throw new Error(`Unknown argument: ${argument}`)
  }
  return options
}

/** Parse one `| \`id\` | Name | Context | Efforts | Rates | Min plan | Notes |` row. */
export function parseReferenceRow(line) {
  const match = /^\|\s*`([^`]+)`\s*\|([^|]*)\|([^|]*)\|([^|]*)\|([^|]*)\|/.exec(line)
  if (!match) return undefined
  const [, id, name, context, efforts, rates] = match
  const effortText = efforts.trim()
  return {
    id: id.trim(),
    name: name.trim(),
    context: context.trim(),
    efforts: effortText === "—" || effortText === "" ? [] : effortText.split(",").map((e) => e.trim()),
    rates: rates.trim(),
  }
}

/** `$0.66/$1.98 · cache $0.022 (write $2.5)` → per-million-token rates. */
export function parseRates(text) {
  const match = /\$([\d.]+)\s*\/\s*\$([\d.]+)\s*·\s*cache\s*\$([\d.]+)(?:\s*\(write\s*\$([\d.]+)\))?/.exec(text)
  if (!match) throw new Error(`Could not parse rates: ${text}`)
  return {
    input: Number(match[1]),
    output: Number(match[2]),
    cacheRead: Number(match[3]),
    cacheWrite: match[4] === undefined ? 0 : Number(match[4]),
  }
}

export function parseReference(markdown) {
  const models = []
  for (const line of markdown.split("\n")) {
    const row = parseReferenceRow(line)
    if (!row) continue
    if (models.some((model) => model.id === row.id)) throw new Error(`Duplicate model id: ${row.id}`)
    for (const effort of row.efforts) {
      if (!validEfforts.includes(effort)) throw new Error(`Unknown effort for ${row.id}: ${effort}`)
    }
    models.push({ ...row, cost: parseRates(row.rates) })
  }
  if (models.length === 0) throw new Error("No model rows found in the Command Code reference")
  return models
}

/**
 * Slice the `{id:"<id>",inputModalities:...}` object literal out of the
 * minified CLI bundle, tracking nested braces and string literals.
 */
export function sliceModelObject(bundle, id) {
  const start = bundle.indexOf(`{id:${JSON.stringify(id)},inputModalities:`)
  if (start < 0) return undefined

  let depth = 0
  let quote = ""
  let escaped = false
  for (let index = start; index < bundle.length; index += 1) {
    const character = bundle[index]
    if (quote) {
      if (escaped) escaped = false
      else if (character === "\\") escaped = true
      else if (character === quote) quote = ""
      continue
    }
    if (character === '"' || character === "'" || character === "`") {
      quote = character
    } else if (character === "{") {
      depth += 1
    } else if (character === "}") {
      depth -= 1
      if (depth === 0) return bundle.slice(start, index + 1)
    }
  }
  throw new Error(`Unterminated model object for ${id}`)
}

function numberField(entry, key) {
  const match = new RegExp(`${key}:(-?[0-9][0-9.e+]*)`).exec(entry)
  if (!match) return undefined
  const value = Number(match[1])
  return Number.isFinite(value) ? value : undefined
}

function stringArrayField(entry, key) {
  const match = new RegExp(`${key}:\\[([^\\]]*)\\]`).exec(entry)
  if (!match) return undefined
  return [...match[1].matchAll(/"([^"]*)"/g)].map((item) => item[1])
}

export function parseBundleMetadata(bundle, ids) {
  const metadata = new Map()
  for (const id of ids) {
    const entry = sliceModelObject(bundle, id)
    if (!entry) continue
    const input = stringArrayField(entry, "inputModalities") ?? ["text"]
    metadata.set(id, {
      input,
      reasoning: entry.includes("reasoning:!0") || entry.includes("reasoningEfforts:["),
      maxOutputTokens: numberField(entry, "maxOutputTokens"),
      contextWindow: numberField(entry, "contextWindow"),
    })
  }
  return metadata
}

export function buildCatalog(version, reference, metadata) {
  return reference.map((model) => {
    const bundle = metadata.get(model.id)
    if (!bundle) throw new Error(`No CLI bundle metadata found for ${model.id}`)
    const efforts = model.efforts
    return {
      id: model.id,
      name: model.name,
      contextWindow: bundle.contextWindow ?? 0,
      efforts,
      reasoning: bundle.reasoning || model.efforts.length > 0,
      input: bundle.input,
      maxOutputTokens: bundle.maxOutputTokens ?? 0,
      cost: model.cost,
    }
  })
}

function renderCatalog(version, models) {
  const lines = []
  lines.push("/**")
  lines.push(" * Generated by scripts/sync-catalog.mjs from the published Command Code CLI")
  lines.push(" * package. Do not edit manually: run `npm run sync:catalog` instead.")
  lines.push(" */")
  lines.push("")
  lines.push(`export const COMMAND_CODE_CLI_VERSION = ${JSON.stringify(version)}`)
  lines.push("")
  lines.push('export type CommandCodeInputModality = "text" | "image"')
  lines.push("")
  lines.push('export type CommandCodeReasoningEffort =')
  for (const effort of validEfforts) lines.push(`  | ${JSON.stringify(effort)}`)
  lines.push("")
  lines.push("export interface CommandCodeModelCost {")
  lines.push("  input: number")
  lines.push("  output: number")
  lines.push("  cacheRead: number")
  lines.push("  cacheWrite: number")
  lines.push("}")
  lines.push("")
  lines.push("export interface CatalogModel {")
  lines.push("  id: string")
  lines.push("  name: string")
  lines.push("  contextWindow: number")
  lines.push("  efforts: readonly CommandCodeReasoningEffort[]")
  lines.push("  reasoning: boolean")
  lines.push("  input: readonly CommandCodeInputModality[]")
  lines.push("  maxOutputTokens: number")
  lines.push("  cost: CommandCodeModelCost")
  lines.push("}")
  lines.push("")
  lines.push("export const CATALOG: readonly CatalogModel[] = [")
  for (const model of models) {
    lines.push("  {")
    lines.push(`    id: ${JSON.stringify(model.id)},`)
    lines.push(`    name: ${JSON.stringify(model.name)},`)
    lines.push(`    contextWindow: ${model.contextWindow},`)
    lines.push(`    efforts: [${model.efforts.map((effort) => JSON.stringify(effort)).join(", ")}],`)
    lines.push(`    reasoning: ${model.reasoning},`)
    lines.push(`    input: [${model.input.map((item) => JSON.stringify(item)).join(", ")}],`)
    lines.push(`    maxOutputTokens: ${model.maxOutputTokens},`)
    lines.push(
      `    cost: { input: ${model.cost.input}, output: ${model.cost.output}, cacheRead: ${model.cost.cacheRead}, cacheWrite: ${model.cost.cacheWrite} },`,
    )
    lines.push("  },")
  }
  lines.push("]")
  lines.push("")
  return lines.join("\n")
}

async function latestVersion() {
  const { stdout } = await execFileAsync("npm", ["view", "command-code", "version"], { encoding: "utf-8" })
  return stdout.trim()
}

async function downloadCli(version, directory) {
  const { stdout } = await execFileAsync("npm", ["pack", `command-code@${version}`, "--silent"], {
    cwd: directory,
    encoding: "utf-8",
  })
  const tarball = stdout.trim().split("\n").pop()
  if (!tarball) throw new Error("npm pack did not report a tarball")
  await execFileAsync("tar", ["xzf", tarball], { cwd: directory })
  return {
    reference: await readFile(join(directory, modelsReferencePath), "utf-8"),
    bundle: await readFile(join(directory, cliBundlePath), "utf-8"),
  }
}

function summarize(previous, next) {
  const parse = (content) =>
    content
      ? new Map(
          [...content.matchAll(/^ {4}id: "([^"]+)",$/gm)].map((match) => [match[1], match[1]]),
        )
      : new Map()
  const before = parse(previous)
  const after = parse(next)
  const added = [...after.keys()].filter((id) => !before.has(id))
  const removed = [...before.keys()].filter((id) => !after.has(id))
  return { added, removed }
}

async function main() {
  const options = parseArguments(process.argv.slice(2))
  const version = options.version ?? (await latestVersion())
  const directory = await mkdtemp(join(tmpdir(), "commandcode-catalog-"))

  try {
    const { reference, bundle } = await downloadCli(version, directory)
    const models = parseReference(reference)
    const metadata = parseBundleMetadata(
      bundle,
      models.map((model) => model.id),
    )
    const catalog = buildCatalog(version, models, metadata)
    const previous = await readFile(catalogPath, "utf-8").catch(() => undefined)
    const next = renderCatalog(version, catalog)
    const { added, removed } = summarize(previous, next)

    console.log(`command-code@${version}: ${catalog.length} models`)
    console.log(`added:   ${added.length > 0 ? added.join(", ") : "none"}`)
    console.log(`removed: ${removed.length > 0 ? removed.join(", ") : "none"}`)

    if (options.check) {
      if (previous !== next) {
        console.error("src/catalog.ts is out of date; run `npm run sync:catalog`.")
        process.exitCode = 1
      }
      return
    }

    await mkdir(dirname(catalogPath), { recursive: true })
    await writeFile(catalogPath, next, "utf-8")
    console.log(`wrote ${catalogPath}`)
  } finally {
    await rm(directory, { recursive: true, force: true })
  }
}

if (process.argv[1] === fileURLToPath(import.meta.url)) {
  await main()
}