export * as GrepTool from "./grep"

import { Tool, ToolFailure, toolText } from "@opencode-ai/llm"
import { Cause, Effect, Layer, Schema } from "effect"
import { FileSystem } from "../filesystem"
import { LocationSearch } from "../location-search"
import { Ripgrep } from "../ripgrep"
import { ToolRegistry } from "./registry"

export const name = "grep"

export const Parameters = Schema.Struct({
  pattern: LocationSearch.GrepInput.fields.pattern.annotate({
    description: "Regex pattern to search for in file contents",
  }),
  path: LocationSearch.GrepInput.fields.path.annotate({
    description: "Relative file or directory to search. Defaults to the active Location.",
  }),
  reference: LocationSearch.GrepInput.fields.reference.annotate({
    description: "Named project reference to search instead of the active Location",
  }),
  include: LocationSearch.GrepInput.fields.include.annotate({
    description: 'File glob to include in the search (for example, "*.js" or "*.{ts,tsx}")',
  }),
  limit: LocationSearch.GrepInput.fields.limit.annotate({
    description: `Maximum matches to return (default: ${LocationSearch.DEFAULT_RESULT_LIMIT})`,
  }),
})

type Success = typeof LocationSearch.GrepResult.Encoded

/** Format raw Location search matches into the familiar concise model output. */
export const toModelOutput = (output: Success) => {
  const lines = output.items.length === 0 ? ["No files found"] : [`Found ${output.items.length} matches`]
  let current = ""
  for (const match of output.items) {
    if (current !== match.resource) {
      if (current) lines.push("")
      current = match.resource
      lines.push(`${match.resource}:`)
    }
    lines.push(`  Line ${match.line}: ${match.lines}${match.linePreviewTruncated ? "..." : ""}`)
  }
  if (output.truncated) {
    lines.push(
      "",
      `(Results are truncated: showing first ${output.items.length} matches. Consider using a more specific path or pattern.)`,
    )
  }
  if (output.partial) lines.push("", "(Some paths were inaccessible and skipped)")
  return lines.join("\n")
}

const definition = Tool.make({
  description:
    "Search file contents by regular expression within the active Location, a named project reference, or an absolute managed tool-output file. Use a path to narrow the search, include to filter files by glob, and limit to bound the match count. Returns concise file resources, line numbers, and bounded line previews.",
  parameters: Parameters,
  success: LocationSearch.GrepResult,
  toModelOutput: ({ output }) => [toolText({ type: "text", text: toModelOutput(output) })],
})

/**
 * Location-scoped grep leaf. FileSystem supplies canonical permission metadata;
 * LocationSearch resolves the current root and owns containment and ripgrep execution.
 *
 * TODO: Revisit root-specific search permission resources if named-reference policy needs independent allow/deny rules.
 */
export const layer = Layer.effectDiscard(
  Effect.gen(function* () {
    const registry = yield* ToolRegistry.Service
    const filesystem = yield* FileSystem.Service
    const search = yield* LocationSearch.Service

    yield* registry.contribute((editor) =>
      editor.set(name, {
        tool: definition,
        execute: ({ parameters, assertPermission }) =>
          Effect.gen(function* () {
            const root = yield* filesystem.resolveRoot(parameters)
            yield* assertPermission({
              action: name,
              resources: [parameters.pattern],
              save: ["*"],
              metadata: {
                root: root.resource,
                reference: parameters.reference,
                path: parameters.path,
                include: parameters.include,
                limit: parameters.limit,
              },
            })
            return yield* search.grep(parameters)
          }).pipe(
            Effect.catchCause((cause) => {
              const error = Cause.squash(cause)
              const message =
                error instanceof Ripgrep.InvalidPatternError
                  ? `Invalid grep pattern ${JSON.stringify(parameters.pattern)}: ${error.message}`
                  : `Unable to grep for ${parameters.pattern}`
              return Effect.fail(new ToolFailure({ message, error }))
            }),
          ),
      }),
    )
  }),
)