/**
 * March Agent SDK - Conversation Client
 * Port of Python march_agent/conversation_client.py
 */

import { APIException } from './exceptions.js'
import type { ConversationData, GetMessagesOptions, ConversationMessageData } from './types.js'

/**
 * HTTP client for interacting with conversation-store API.
 */
export class ConversationClient {
    private readonly baseUrl: string

    constructor(baseUrl: string) {
        this.baseUrl = baseUrl.replace(/\/$/, '')
    }

    /**
     * Get conversation metadata.
     */
    async getConversation(conversationId: string): Promise<ConversationData> {
        const url = `${this.baseUrl}/conversations/${conversationId}`

        try {
            const response = await fetch(url)

            if (response.status === 404) {
                throw new APIException(`Conversation ${conversationId} not found`, 404)
            }

            if (!response.ok) {
                throw new APIException(`Failed to fetch conversation: ${response.status}`, response.status)
            }

            return await response.json() as ConversationData
        } catch (error) {
            if (error instanceof APIException) throw error
            throw new APIException(`Failed to fetch conversation: ${error}`)
        }
    }

    /**
     * Get messages from a conversation.
     */
    async getMessages(
        conversationId: string,
        options: GetMessagesOptions = {}
    ): Promise<ConversationMessageData[]> {
        const url = new URL(`${this.baseUrl}/conversations/${conversationId}/messages`)

        const params: Record<string, string> = {
            limit: String(Math.min(options.limit ?? 100, 1000)),
            offset: String(options.offset ?? 0),
        }

        if (options.role) params.role = options.role
        if (options.from) params.from = options.from
        if (options.to) params.to = options.to

        Object.entries(params).forEach(([key, value]) => {
            url.searchParams.set(key, value)
        })

        try {
            const response = await fetch(url.toString())

            if (response.status === 404) {
                throw new APIException(`Conversation ${conversationId} not found`, 404)
            }

            if (!response.ok) {
                throw new APIException(`Failed to fetch messages: ${response.status}`, response.status)
            }

            return await response.json() as ConversationMessageData[]
        } catch (error) {
            if (error instanceof APIException) throw error
            throw new APIException(`Failed to fetch messages: ${error}`)
        }
    }

    /**
     * Update conversation fields (PATCH).
     */
    async updateConversation(
        conversationId: string,
        data: Partial<ConversationData>
    ): Promise<ConversationData> {
        const url = `${this.baseUrl}/conversations/${conversationId}`

        try {
            const response = await fetch(url, {
                method: 'PATCH',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify(data),
            })

            if (!response.ok) {
                throw new APIException(`Failed to update conversation: ${response.status}`, response.status)
            }

            return await response.json() as ConversationData
        } catch (error) {
            if (error instanceof APIException) throw error
            throw new APIException(`Failed to update conversation: ${error}`)
        }
    }
}