import { AzureOpenAI } from "openai";
import type { ResponseCreateParamsStreaming } from "openai/resources/responses/responses.js";
import { getEnvApiKey } from "../env-api-keys.js";
import { supportsXhigh } from "../models.js";
import type {
	Api,
	AssistantMessage,
	Context,
	Model,
	SimpleStreamOptions,
	StreamFunction,
	StreamOptions,
} from "../types.js";
import { AssistantMessageEventStream } from "../utils/event-stream.js";
import { headersToRecord } from "../utils/headers.js";
import { convertResponsesMessages, convertResponsesTools, processResponsesStream } from "./openai-responses-shared.js";
import { buildBaseOptions, clampReasoning } from "./simple-options.js";

const DEFAULT_AZURE_API_VERSION = "v1";
const AZURE_TOOL_CALL_PROVIDERS = new Set(["openai", "openai-codex", "opencode", "azure-openai-responses"]);

function parseDeploymentNameMap(value: string | undefined): Map<string, string> {
	const map = new Map<string, string>();
	if (!value) return map;
	for (const entry of value.split(",")) {
		const trimmed = entry.trim();
		if (!trimmed) continue;
		const [modelId, deploymentName] = trimmed.split("=", 2);
		if (!modelId || !deploymentName) continue;
		map.set(modelId.trim(), deploymentName.trim());
	}
	return map;
}

function resolveDeploymentName(model: Model<"azure-openai-responses">, options?: AzureOpenAIResponsesOptions): string {
	if (options?.azureDeploymentName) {
		return options.azureDeploymentName;
	}
	const mappedDeployment = parseDeploymentNameMap(process.env.AZURE_OPENAI_DEPLOYMENT_NAME_MAP).get(model.id);
	return mappedDeployment || model.id;
}

// Azure OpenAI Responses-specific options
export interface AzureOpenAIResponsesOptions extends StreamOptions {
	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh";
	reasoningSummary?: "auto" | "detailed" | "concise" | null;
	azureApiVersion?: string;
	azureResourceName?: string;
	azureBaseUrl?: string;
	azureDeploymentName?: string;
}

/**
 * Generate function for Azure OpenAI Responses API
 */
export const streamAzureOpenAIResponses: StreamFunction<"azure-openai-responses", AzureOpenAIResponsesOptions> = (
	model: Model<"azure-openai-responses">,
	context: Context,
	options?: AzureOpenAIResponsesOptions,
): AssistantMessageEventStream => {
	const stream = new AssistantMessageEventStream();

	// Start async processing
	(async () => {
		const deploymentName = resolveDeploymentName(model, options);

		const output: AssistantMessage = {
			role: "assistant",
			content: [],
			api: "azure-openai-responses" as Api,
			provider: model.provider,
			model: model.id,
			usage: {
				input: 0,
				output: 0,
				cacheRead: 0,
				cacheWrite: 0,
				totalTokens: 0,
				cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
			},
			stopReason: "stop",
			timestamp: Date.now(),
		};

		try {
			// Create Azure OpenAI client
			const apiKey = options?.apiKey || getEnvApiKey(model.provider) || "";
			const client = createClient(model, apiKey, options);
			let params = buildParams(model, context, options, deploymentName);
			const nextParams = await options?.onPayload?.(params, model);
			if (nextParams !== undefined) {
				params = nextParams as ResponseCreateParamsStreaming;
			}
			const { data: openaiStream, response } = await client.responses
				.create(params, options?.signal ? { signal: options.signal } : undefined)
				.withResponse();
			await options?.onResponse?.({ status: response.status, headers: headersToRecord(response.headers) }, model);
			stream.push({ type: "start", partial: output });

			await processResponsesStream(openaiStream, output, stream, model);

			if (options?.signal?.aborted) {
				throw new Error("Request was aborted");
			}

			if (output.stopReason === "aborted" || output.stopReason === "error") {
				throw new Error("An unknown error occurred");
			}

			stream.push({ type: "done", reason: output.stopReason, message: output });
			stream.end();
		} catch (error) {
			for (const block of output.content) {
				delete (block as { index?: number }).index;
				// partialJson is only a streaming scratch buffer; never persist it.
				delete (block as { partialJson?: string }).partialJson;
			}
			output.stopReason = options?.signal?.aborted ? "aborted" : "error";
			output.errorMessage = error instanceof Error ? error.message : JSON.stringify(error);
			stream.push({ type: "error", reason: output.stopReason, error: output });
			stream.end();
		}
	})();

	return stream;
};

export const streamSimpleAzureOpenAIResponses: StreamFunction<"azure-openai-responses", SimpleStreamOptions> = (
	model: Model<"azure-openai-responses">,
	context: Context,
	options?: SimpleStreamOptions,
): AssistantMessageEventStream => {
	const apiKey = options?.apiKey || getEnvApiKey(model.provider);
	if (!apiKey) {
		throw new Error(`No API key for provider: ${model.provider}`);
	}

	const base = buildBaseOptions(model, options, apiKey);
	const reasoningEffort = supportsXhigh(model) ? options?.reasoning : clampReasoning(options?.reasoning);

	return streamAzureOpenAIResponses(model, context, {
		...base,
		reasoningEffort,
	} satisfies AzureOpenAIResponsesOptions);
};

function normalizeAzureBaseUrl(baseUrl: string): string {
	return baseUrl.replace(/\/+$/, "");
}

function buildDefaultBaseUrl(resourceName: string): string {
	return `https://${resourceName}.openai.azure.com/openai/v1`;
}

function resolveAzureConfig(
	model: Model<"azure-openai-responses">,
	options?: AzureOpenAIResponsesOptions,
): { baseUrl: string; apiVersion: string } {
	const apiVersion = options?.azureApiVersion || process.env.AZURE_OPENAI_API_VERSION || DEFAULT_AZURE_API_VERSION;

	const baseUrl = options?.azureBaseUrl?.trim() || process.env.AZURE_OPENAI_BASE_URL?.trim() || undefined;
	const resourceName = options?.azureResourceName || process.env.AZURE_OPENAI_RESOURCE_NAME;

	let resolvedBaseUrl = baseUrl;

	if (!resolvedBaseUrl && resourceName) {
		resolvedBaseUrl = buildDefaultBaseUrl(resourceName);
	}

	if (!resolvedBaseUrl && model.baseUrl) {
		resolvedBaseUrl = model.baseUrl;
	}

	if (!resolvedBaseUrl) {
		throw new Error(
			"Azure OpenAI base URL is required. Set AZURE_OPENAI_BASE_URL or AZURE_OPENAI_RESOURCE_NAME, or pass azureBaseUrl, azureResourceName, or model.baseUrl.",
		);
	}

	return {
		baseUrl: normalizeAzureBaseUrl(resolvedBaseUrl),
		apiVersion,
	};
}

function createClient(model: Model<"azure-openai-responses">, apiKey: string, options?: AzureOpenAIResponsesOptions) {
	if (!apiKey) {
		if (!process.env.AZURE_OPENAI_API_KEY) {
			throw new Error(
				"Azure OpenAI API key is required. Set AZURE_OPENAI_API_KEY environment variable or pass it as an argument.",
			);
		}
		apiKey = process.env.AZURE_OPENAI_API_KEY;
	}

	const headers = { ...model.headers };

	if (options?.headers) {
		Object.assign(headers, options.headers);
	}

	const { baseUrl, apiVersion } = resolveAzureConfig(model, options);

	return new AzureOpenAI({
		apiKey,
		apiVersion,
		dangerouslyAllowBrowser: true,
		defaultHeaders: headers,
		baseURL: baseUrl,
	});
}

function buildParams(
	model: Model<"azure-openai-responses">,
	context: Context,
	options: AzureOpenAIResponsesOptions | undefined,
	deploymentName: string,
) {
	const messages = convertResponsesMessages(model, context, AZURE_TOOL_CALL_PROVIDERS);

	const params: ResponseCreateParamsStreaming = {
		model: deploymentName,
		input: messages,
		stream: true,
		prompt_cache_key: options?.sessionId,
	};

	if (options?.maxTokens) {
		params.max_output_tokens = options?.maxTokens;
	}

	if (options?.temperature !== undefined) {
		params.temperature = options?.temperature;
	}

	if (context.tools) {
		params.tools = convertResponsesTools(context.tools);
	}

	if (model.reasoning) {
		if (options?.reasoningEffort || options?.reasoningSummary) {
			params.reasoning = {
				effort: options?.reasoningEffort || "medium",
				summary: options?.reasoningSummary || "auto",
			};
			params.include = ["reasoning.encrypted_content"];
		} else {
			params.reasoning = { effort: "none" };
		}
	}

	return params;
}