package ollama

import (
	"bufio"
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
)

type PullModelRequest struct {
	Model    string `json:"name"`
	Insecure *bool  `json:"insecure,omitempty"`
	Stream   *bool  `json:"stream,omitempty"`
}

type PullModelResponse struct {
	Status string `json:"status"`
}

type PullModelResponseStream struct {
	Status    string `json:"status"`
	Digest    string `json:"digest"`
	Total     int    `json:"total"`
	Completed int    `json:"completed"`
}

func (o Ollama) PullModel(reqBody PullModelRequest) (PullModelResponse, error) {
	reqBody.Stream = PtrOf(false)
	reqBodyBytes, err := json.Marshal(reqBody)
	if err != nil {
		return PullModelResponse{}, err
	}

	req, err := http.NewRequest(http.MethodPost, fmt.Sprintf("%s/pull", o.baseUrl), bytes.NewReader(reqBodyBytes))
	if err != nil {
		return PullModelResponse{}, err
	}

	for key, val := range o.customHeaders {
		req.Header.Set(key, val)
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return PullModelResponse{}, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return PullModelResponse{}, errors.New("status code is not 200")
	}

	var respBody PullModelResponse
	if err := json.NewDecoder(resp.Body).Decode(&respBody); err != nil {
		return PullModelResponse{}, err
	}
	return respBody, nil
}

func (o Ollama) PullModelStream(reqBody PullModelRequest, onChunk func(chunk PullModelResponseStream)) error {
	reqBody.Stream = PtrOf(true)
	reqBodyBytes, err := json.Marshal(reqBody)
	if err != nil {
		return err
	}

	req, err := http.NewRequest(http.MethodPost, fmt.Sprintf("%s/pull", o.baseUrl), bytes.NewReader(reqBodyBytes))
	if err != nil {
		return err
	}

	for key, val := range o.customHeaders {
		req.Header.Set(key, val)
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return errors.New("status code is not 200")
	}

	scanner := bufio.NewScanner(resp.Body)

	for scanner.Scan() {
		line := bytes.TrimSpace(scanner.Bytes())

		var chunk PullModelResponseStream
		if err := json.Unmarshal(line, &chunk); err != nil {
			return err
		}

		onChunk(chunk)
		if chunk.Status == "success" {
			break
		}
	}

	if err := scanner.Err(); err != nil {
		return err
	}

	return nil
}