import {
  BuildContext,
  BuildExtension,
  BuildLayer,
  RegisteredPlugin,
  ResolvedConfig,
} from "@trigger.dev/core/v3/build";
import { BuildManifest, BuildTarget } from "@trigger.dev/core/v3/schemas";
import * as esbuild from "esbuild";
import { logger } from "../utilities/logger.js";
import { resolveModule } from "./resolveModule.js";
import { log, spinner } from "@clack/prompts";

export interface InternalBuildContext extends BuildContext {
  getLayers(): BuildLayer[];
  clearLayers(): void;
  getPlugins(): RegisteredPlugin[];
  appendExtension(extension: BuildExtension): void;
  prependExtension(extension: BuildExtension): void;
  getExtensions(): BuildExtension[];
}

export async function notifyExtensionOnBuildStart(context: InternalBuildContext) {
  for (const extension of context.getExtensions()) {
    if (extension.onBuildStart) {
      await extension.onBuildStart(context);
    }
  }
}

export async function notifyExtensionOnBuildComplete(
  context: InternalBuildContext,
  manifest: BuildManifest
): Promise<BuildManifest> {
  let $manifest = manifest;

  for (const extension of context.getExtensions()) {
    if (extension.onBuildComplete) {
      try {
        await extension.onBuildComplete(context, $manifest);
        logger.debug(`Applying extension ${extension.name} to manifest`, {
          context,
          manifest,
        });
        $manifest = applyContextLayersToManifest(context, $manifest);
      } catch (error) {
        logger.error(`Failed to apply extension ${extension.name} onBuildComplete`, error);
      }
    }
  }

  return $manifest;
}

export function createBuildContext(
  target: BuildTarget,
  config: ResolvedConfig
): InternalBuildContext {
  const layers: BuildLayer[] = [];
  const registeredPlugins: RegisteredPlugin[] = [];
  const extensions: BuildExtension[] = config.build.extensions ?? [];

  return {
    target,
    config: config,
    workingDir: config.workingDir,
    addLayer(layer) {
      layers.push(layer);
    },
    getLayers() {
      return layers;
    },
    clearLayers() {
      layers.splice(0);
    },
    registerPlugin(plugin, options) {
      if (options?.target && options.target !== target) {
        return;
      }

      registeredPlugins.push({ plugin, ...options });
    },
    getPlugins() {
      return registeredPlugins;
    },
    resolvePath: async (path) => {
      try {
        return await resolveModule(path, config.workingDir);
      } catch (error) {
        return undefined;
      }
    },
    getExtensions() {
      return extensions;
    },
    appendExtension(extension) {
      extensions.push(extension);
    },
    prependExtension(extension) {
      extensions.unshift(extension);
    },
    logger: {
      debug: (...args) => logger.debug(...args),
      log: (...args) => logger.log(...args),
      warn: (...args) => logger.warn(...args),
      progress: (message) => log.message(message),
      spinner: (message) => {
        const $spinner = spinner();
        $spinner.start(message);
        return $spinner;
      },
    },
  };
}

function applyContextLayersToManifest(
  context: InternalBuildContext,
  manifest: BuildManifest
): BuildManifest {
  for (const layer of context.getLayers()) {
    manifest = applyLayerToManifest(layer, manifest);
  }

  context.clearLayers();

  return manifest;
}

function applyLayerToManifest(layer: BuildLayer, manifest: BuildManifest): BuildManifest {
  let $manifest = { ...manifest };

  if (layer.commands) {
    $manifest.build.commands ??= [];
    $manifest.build.commands = $manifest.build.commands.concat(layer.commands);
  }

  if (layer.build?.env) {
    $manifest.build.env ??= {};
    Object.assign($manifest.build.env, layer.build.env);
  }

  if (layer.deploy?.env) {
    $manifest.deploy.env ??= {};
    $manifest.deploy.sync ??= {};
    $manifest.deploy.sync.env ??= {};

    for (const [key, value] of Object.entries(layer.deploy.env)) {
      if (!value) {
        continue;
      }

      if (layer.deploy.override || $manifest.deploy.env[key] === undefined) {
        const existingValue = $manifest.deploy.env[key];

        if (existingValue !== value) {
          $manifest.deploy.sync.env[key] = value;
        }
      }
    }
  }

  if (layer.dependencies) {
    const externals = $manifest.externals ?? [];

    for (const [name, version] of Object.entries(layer.dependencies)) {
      externals.push({ name, version });
    }

    $manifest.externals = externals;
  }

  if (layer.image) {
    $manifest.image ??= {};
    $manifest.image.instructions ??= [];
    $manifest.image.pkgs ??= [];

    if (layer.image.instructions) {
      $manifest.image.instructions = $manifest.image.instructions.concat(layer.image.instructions);
    }

    if (layer.image.pkgs) {
      $manifest.image.pkgs = $manifest.image.pkgs.concat(layer.image.pkgs);
      $manifest.image.pkgs = Array.from(new Set($manifest.image.pkgs));
    }
  }

  return $manifest;
}

export function resolvePluginsForContext(context: InternalBuildContext): esbuild.Plugin[] {
  const registeredPlugins = context.getPlugins();

  if (registeredPlugins.length === 0) {
    return [];
  }

  const sortedPlugins = [...registeredPlugins].sort((a, b) => {
    const order = { first: 0, undefined: 1, last: 2, $head: -1 };
    const aOrder = order[a.placement as keyof typeof order] ?? 1;
    const bOrder = order[b.placement as keyof typeof order] ?? 1;

    // If the placement order is different, sort based on that
    if (aOrder !== bOrder) {
      return aOrder - bOrder;
    }

    // If the placement order is the same, maintain original order
    return registeredPlugins.indexOf(a) - registeredPlugins.indexOf(b);
  });

  return sortedPlugins.map((plugin) => plugin.plugin);
}
