import { spawn } from "child_process"
import { promises as fs } from "fs"
import path from "path"
import { rimraf } from "rimraf"
import { registrySchema } from "shadcn/schema"
import {
  createStyleMap,
  transformDirection,
  transformStyle,
} from "shadcn/utils"

import { getAllBlocks } from "@/lib/blocks"
import { legacyStyles } from "@/registry/_legacy-styles"
import { BASES, type Base } from "@/registry/bases"
import { PRESETS } from "@/registry/config"
import { STYLES } from "@/registry/styles"

// This is a list of styles that we want to check into tracking.
// This is used by the v4 site.
const WHITELISTED_STYLES = ["new-york-v4"]

// Collect paths for batch prettier formatting at the end.
const prettierPaths: string[] = []

function getStylesToBuild() {
  const stylesToBuild: { name: string; title: string }[] = [...legacyStyles]

  for (const base of BASES) {
    for (const style of STYLES) {
      stylesToBuild.push({
        name: `${base.name}-${style.name}`,
        title: `${base.title} ${style.title}`,
      })
    }
  }

  return stylesToBuild
}

try {
  const totalStart = performance.now()

  console.log("🏗️ Building bases...")
  await buildBasesIndex(Array.from(BASES))
  await buildBases(Array.from(BASES))

  const stylesToBuild = getStylesToBuild()

  // Build index for legacy styles and whitelisted base-style combinations.
  console.log(`📦 Building registry/__index__.tsx...`)
  const stylesForIndex = WHITELISTED_STYLES.map((name) => ({
    name,
    title: name,
  }))
  await buildRegistryIndex(stylesForIndex)

  console.log("💅 Building styles...")
  // Build all styles in parallel.
  await Promise.all(
    stylesToBuild.map(async (style) => {
      await buildRegistryJsonFile(style.name)
      await buildRegistry(style.name)
      console.log(`   ✅ ${style.name}`)
    })
  )

  console.log("\n🗂️ Building registry/__blocks__.json...")
  await buildBlocksIndex()

  console.log("\n⚙️ Building public/r/config.json...")
  await buildConfig()

  // Copy UI to examples before cleanup.
  console.log("\n📋 Copying UI to examples...")
  await copyUIToExamples()

  // Build RTL variants of examples.
  console.log("\n🔄 Building RTL examples...")
  await buildRtlExamples()

  console.log("\n📋 Building public/r/registries.json...")
  await buildRegistriesJson()

  // Batch format all collected files with prettier at the end.
  if (prettierPaths.length > 0) {
    console.log(`\n✨ Formatting ${prettierPaths.length} files...`)
    await batchPrettier(prettierPaths)
  }

  // Clean up intermediate files and generated base directories.
  console.log("\n🧹 Cleaning up...")
  await cleanUp(stylesToBuild)

  const elapsed = ((performance.now() - totalStart) / 1000).toFixed(2)
  console.log(`\n✅ Build complete in ${elapsed}s!`)
} catch (error) {
  console.error(error)
  process.exit(1)
}

async function buildBasesIndex(bases: Base[]) {
  // Import all registries in parallel.
  const registryImports = await Promise.all(
    bases.map(async (base) => {
      const { registry: importedRegistry } = await import(
        `../registry/bases/${base.name}/registry.ts`
      )
      return { base, importedRegistry }
    })
  )

  let index = `// @ts-nocheck
// This file is autogenerated by scripts/build-registry.ts
// Do not edit this file directly.
import "server-only"
import * as React from "react"

export const Index: Record<string, Record<string, any>> = {`

  for (const { base, importedRegistry } of registryImports) {
    // Validate the registry schema.
    const parseResult = registrySchema.safeParse(importedRegistry)
    if (!parseResult.success) {
      console.error(`❌ Registry validation failed for ${base.name}:`)
      console.error(parseResult.error.format())
      throw new Error(`Invalid registry schema for ${base.name}`)
    }

    const registry = parseResult.data

    index += `
  "${base.name}": {`

    for (const item of registry.items) {
      // Skip demos - they're handled by the examples index.
      if (item.type === "registry:internal") {
        continue
      }

      const files =
        item.files?.map((file) => ({
          path: typeof file === "string" ? file : file.path,
          type: typeof file === "string" ? item.type : file.type,
          target: typeof file === "string" ? undefined : file.target,
        })) ?? []

      if (files.length === 0) {
        continue
      }

      const componentPath = item.files?.[0]?.path
        ? `@/registry/bases/${base.name}/${item.files[0].path}`
        : ""

      index += `
    "${item.name}": {
      name: "${item.name}",
      title: "${item.title}",
      description: "${item.description ?? ""}",
      type: "${item.type}",
      registryDependencies: ${JSON.stringify(item.registryDependencies)},
      files: [${files.map((file) => {
        const filePath = `registry/bases/${base.name}/${file.path}`
        return `{
        path: "${filePath}",
        type: "${file.type}",
        target: "${file.target ?? ""}"
      }`
      })}],
      component: ${
        componentPath
          ? `React.lazy(async () => {
        const mod = await import("${componentPath}")
        const exportName = Object.keys(mod).find(key => typeof mod[key] === 'function' || typeof mod[key] === 'object') || item.name
        return { default: mod.default || mod[exportName] }
      })`
          : "null"
      },
      categories: ${JSON.stringify(item.categories)},
      meta: ${JSON.stringify(item.meta)},
    },`
    }

    index += `
  },`
  }

  index += `
}`

  // Write unified index.
  await rimraf(path.join(process.cwd(), "registry/bases/__index__.tsx"))
  await fs.writeFile(
    path.join(process.cwd(), "registry/bases/__index__.tsx"),
    index
  )
}

async function buildBases(bases: Base[]) {
  // Pre-import all base registries and style CSS files in parallel.
  const [baseImports, styleMaps] = await Promise.all([
    Promise.all(
      bases.map(async (base) => {
        const { registry: baseRegistry } = await import(
          `../registry/bases/${base.name}/registry.ts`
        )
        const result = registrySchema.safeParse(baseRegistry)
        if (!result.success) {
          console.error(`❌ Registry validation failed for ${base.name}:`)
          console.error(result.error.format())
          throw new Error(`Invalid registry schema for ${base.name}`)
        }
        const registryItems = result.data.items.filter(
          (item) => item.type !== "registry:internal"
        )
        return { base, baseRegistry, registryItems }
      })
    ),
    Promise.all(
      STYLES.map(async (style) => {
        const styleContent = await fs.readFile(
          path.join(process.cwd(), `registry/styles/style-${style.name}.css`),
          "utf8"
        )
        return { style, styleMap: createStyleMap(styleContent) }
      })
    ),
  ])

  // Build all base-style combinations in parallel.
  const combinations: Array<{
    base: Base
    style: (typeof STYLES)[number]
    baseRegistry: (typeof baseImports)[number]["baseRegistry"]
    registryItems: (typeof baseImports)[number]["registryItems"]
    styleMap: Record<string, string>
  }> = []

  for (const { base, baseRegistry, registryItems } of baseImports) {
    for (const { style, styleMap } of styleMaps) {
      combinations.push({ base, style, baseRegistry, registryItems, styleMap })
    }
  }

  await Promise.all(
    combinations.map(
      async ({ base, style, baseRegistry, registryItems, styleMap }) => {
        console.log(`   ✅ ${base.name}-${style.name}...`)

        const styleOutputDir = path.join(
          process.cwd(),
          `registry/${base.name}-${style.name}`
        )
        await rimraf(styleOutputDir)
        await fs.mkdir(styleOutputDir, { recursive: true })

        // Create a registry.ts file in the output directory.
        const styleRegistry = { ...baseRegistry, items: registryItems }
        const registryTs = `export const registry = ${JSON.stringify(styleRegistry, null, 2)}\n`
        await fs.writeFile(path.join(styleOutputDir, "registry.ts"), registryTs)

        // Process all files in parallel.
        await Promise.all(
          registryItems.flatMap((registryItem) => {
            if (!registryItem.files || registryItem.files.length === 0) {
              return []
            }
            return registryItem.files.map(async (file: { path: string }) => {
              const source = await fs.readFile(
                path.join(
                  process.cwd(),
                  `registry/bases/${base.name}/${file.path}`
                ),
                "utf8"
              )

              const fileExtension = path.extname(file.path)
              const shouldTransform =
                fileExtension === ".tsx" || fileExtension === ".ts"

              let transformedContent = source

              if (shouldTransform) {
                transformedContent = await transformStyle(source, {
                  styleMap: styleMap,
                })
                transformedContent = transformedContent.replace(
                  new RegExp(`@/registry/bases/${base.name}/`, "g"),
                  `@/registry/${base.name}-${style.name}/`
                )
              }

              const outputPath = path.join(
                process.cwd(),
                `registry/${base.name}-${style.name}/${file.path}`
              )
              await fs.mkdir(path.dirname(outputPath), { recursive: true })
              await fs.writeFile(outputPath, transformedContent)
            })
          })
        )
      }
    )
  )
}

async function buildRegistryIndex(styles: { name: string; title: string }[]) {
  // Import all registries in parallel.
  const registryImports = await Promise.all(
    styles.map(async (style) => {
      const { registry: importedRegistry } = await import(
        `../registry/${style.name}/registry.ts`
      )
      return { style, importedRegistry }
    })
  )

  let index = `// @ts-nocheck
// This file is autogenerated by scripts/build-registry.ts
// Do not edit this file directly.
import * as React from "react"

export const Index: Record<string, Record<string, any>> = {`

  for (const { style, importedRegistry } of registryImports) {
    const parseResult = registrySchema.safeParse(importedRegistry)
    if (!parseResult.success) {
      console.error(`❌ Registry validation failed for ${style.name}:`)
      console.error(parseResult.error.format())
      throw new Error(`Invalid registry schema for ${style.name}`)
    }

    const registry = parseResult.data

    index += `
  "${style.name}": {`

    for (const item of registry.items) {
      if (item.type === "registry:internal") {
        continue
      }

      const files =
        item.files?.map((file) => ({
          path: typeof file === "string" ? file : file.path,
          type: typeof file === "string" ? item.type : file.type,
          target: typeof file === "string" ? undefined : file.target,
        })) ?? []

      if (files.length === 0) {
        continue
      }

      const componentPath = item.files?.[0]?.path
        ? `@/registry/${style.name}/${item.files[0].path}`
        : ""

      index += `
    "${item.name}": {
      name: "${item.name}",
      title: "${item.title}",
      description: "${item.description ?? ""}",
      type: "${item.type}",
      registryDependencies: ${JSON.stringify(item.registryDependencies)},
      files: [${files.map((file) => {
        const filePath = `registry/${style.name}/${file.path}`
        return `{
        path: "${filePath}",
        type: "${file.type}",
        target: "${file.target ?? ""}"
      }`
      })}],
      component: ${
        componentPath
          ? `React.lazy(async () => {
        const mod = await import("${componentPath}")
        const exportName = Object.keys(mod).find(key => typeof mod[key] === 'function' || typeof mod[key] === 'object') || item.name
        return { default: mod.default || mod[exportName] }
      })`
          : "null"
      },
      categories: ${JSON.stringify(item.categories)},
      meta: ${JSON.stringify(item.meta)},
    },`
    }

    index += `
  },`
  }

  index += `
}`

  await rimraf(path.join(process.cwd(), "registry/__index__.tsx"))
  await fs.writeFile(path.join(process.cwd(), "registry/__index__.tsx"), index)
}

async function buildRegistryJsonFile(styleName: string) {
  const { registry: importedRegistry } = await import(
    `../registry/${styleName}/registry.ts`
  )

  const parseResult = registrySchema.safeParse(importedRegistry)
  if (!parseResult.success) {
    console.error(`❌ Registry validation failed for ${styleName}:`)
    console.error(parseResult.error.format())
    throw new Error(`Invalid registry schema for ${styleName}`)
  }

  const registry = parseResult.data

  const fixedRegistry = {
    ...registry,
    items: registry.items.map((item) => {
      const files = item.files?.map((file) => ({
        ...file,
        path: `registry/${styleName}/${file.path}`,
      }))
      return { ...item, files }
    }),
  }

  const outputDir = path.join(process.cwd(), `public/r/styles/${styleName}`)
  await fs.mkdir(outputDir, { recursive: true })

  const registryJsonPath = path.join(outputDir, "registry.json")
  await fs.writeFile(registryJsonPath, JSON.stringify(fixedRegistry, null, 2))
  prettierPaths.push(registryJsonPath)

  const tempRegistryPath = path.join(
    process.cwd(),
    `registry-${styleName}.json`
  )
  await fs.writeFile(tempRegistryPath, JSON.stringify(fixedRegistry, null, 2))
}

async function buildRegistry(styleName: string) {
  const outputPath = `public/r/styles/${styleName}`
  await new Promise<void>((resolve, reject) => {
    const proc = spawn(
      "node",
      [
        "../../packages/shadcn/dist/index.js",
        "build",
        `registry-${styleName}.json`,
        "--output",
        outputPath,
      ],
      { cwd: process.cwd(), stdio: "pipe" }
    )
    let stderr = ""
    proc.stderr?.on("data", (data) => (stderr += data))
    proc.on("close", (code) => {
      if (code !== 0) {
        reject(new Error(`Process exited with code ${code}: ${stderr}`))
      } else {
        resolve()
      }
    })
    proc.on("error", reject)
  })
}

async function buildBlocksIndex() {
  const blocks = await getAllBlocks(["registry:block"])

  const payload = blocks.map((block) => ({
    name: block.name,
    description: block.description,
    categories: block.categories,
  }))

  await rimraf(path.join(process.cwd(), "registry/__blocks__.json"))
  const blocksJsonPath = path.join(process.cwd(), "registry/__blocks__.json")
  await fs.writeFile(blocksJsonPath, JSON.stringify(payload, null, 2))
  prettierPaths.push(blocksJsonPath)
}

async function cleanUp(stylesToBuild: { name: string; title: string }[]) {
  // Clean up all in parallel.
  const cleanupPromises: Promise<boolean>[] = []

  for (const style of stylesToBuild) {
    cleanupPromises.push(
      rimraf(path.join(process.cwd(), `registry-${style.name}.json`))
    )
  }

  for (const base of BASES) {
    for (const style of STYLES) {
      const baseName = `${base.name}-${style.name}`
      if (!WHITELISTED_STYLES.includes(baseName)) {
        const baseDir = path.join(process.cwd(), `registry/${baseName}`)
        console.log(`   🗑️ ${baseName}`)
        cleanupPromises.push(rimraf(baseDir))
      }
    }
  }

  await Promise.all(cleanupPromises)
}

async function buildConfig() {
  const config = { presets: PRESETS }
  const outputPath = path.join(process.cwd(), "public/r/config.json")
  await fs.writeFile(outputPath, JSON.stringify(config, null, 2))
  prettierPaths.push(outputPath)
}

async function copyUIToExamples() {
  const defaultStyle = "nova"
  const directories = ["ui", "lib", "hooks"]

  // Build all copy tasks.
  const copyTasks: Array<{ base: Base; dir: string }> = []
  for (const base of BASES) {
    for (const dir of directories) {
      copyTasks.push({ base, dir })
    }
  }

  await Promise.all(
    copyTasks.map(async ({ base, dir }) => {
      const sourceStyle = `${base.name}-${defaultStyle}`
      const fromDir = path.join(process.cwd(), `registry/${sourceStyle}/${dir}`)
      const toDir = path.join(process.cwd(), `examples/${base.name}/${dir}`)

      try {
        await fs.access(fromDir)
      } catch {
        console.log(`   ⚠️ registry/${sourceStyle}/${dir} not found, skipping`)
        return
      }

      await rimraf(toDir)
      await fs.mkdir(toDir, { recursive: true })

      const files = await fs.readdir(fromDir)
      await Promise.all(
        files.map(async (file) => {
          const sourcePath = path.join(fromDir, file)
          const targetPath = path.join(toDir, file)
          let content = await fs.readFile(sourcePath, "utf-8")
          content = content.replace(
            new RegExp(`@/registry/${sourceStyle}/`, "g"),
            `@/examples/${base.name}/`
          )
          await fs.writeFile(targetPath, content)
        })
      )

      console.log(
        `   ✅ registry/${sourceStyle}/${dir} → examples/${base.name}/${dir}`
      )
    })
  )
}

async function buildRegistriesJson() {
  const directoryPath = path.join(process.cwd(), "registry/directory.json")
  const directoryContent = await fs.readFile(directoryPath, "utf8")
  const directory = JSON.parse(directoryContent) as Array<{
    name: string
    homepage?: string
    url: string
    description?: string
    featured?: boolean
    logo?: string
  }>

  const registries = directory.map((entry) => ({
    name: entry.name,
    homepage: entry.homepage,
    url: entry.url,
    description: entry.description,
  }))

  const outputPath = path.join(process.cwd(), "public/r/registries.json")
  await fs.writeFile(outputPath, JSON.stringify(registries, null, 2))
  prettierPaths.push(outputPath)
}

async function buildRtlExamples() {
  // Process all bases in parallel.
  await Promise.all(
    Array.from(BASES).map(async (base) => {
      const sourceDir = path.join(process.cwd(), `examples/${base.name}/ui`)
      const targetDir = path.join(process.cwd(), `examples/${base.name}/ui-rtl`)

      try {
        await fs.access(sourceDir)
      } catch {
        console.log(`   ⚠️ examples/${base.name}/ui not found, skipping...`)
        return
      }

      await rimraf(targetDir)
      await fs.mkdir(targetDir, { recursive: true })

      const files = await fs.readdir(sourceDir)
      await Promise.all(
        files
          .filter((file) => file.endsWith(".tsx") || file.endsWith(".ts"))
          .map(async (file) => {
            const sourcePath = path.join(sourceDir, file)
            const targetPath = path.join(targetDir, file)

            let content = await fs.readFile(sourcePath, "utf-8")
            content = await transformDirection(content, true)
            content = content.replace(
              new RegExp(`@/examples/${base.name}/ui/`, "g"),
              `@/examples/${base.name}/ui-rtl/`
            )
            await fs.writeFile(targetPath, content)
          })
      )

      console.log(`   ✅ examples/${base.name}/ui-rtl`)
    })
  )
}

async function batchPrettier(paths: string[]) {
  if (paths.length === 0) return

  await new Promise<void>((resolve, reject) => {
    const proc = spawn("npx", ["prettier", "--write", ...paths], {
      cwd: process.cwd(),
      stdio: "pipe",
    })
    proc.on("close", () => resolve())
    proc.on("error", reject)
  })
}