package ollama

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

type CreateModelRequest struct {
	Model      string                      `json:"model"`
	From       string                      `json:"from,omitempty"`
	Template   string                      `json:"template,omitempty"`
	License    string                      `json:"license,omitempty"`
	System     string                      `json:"system,omitempty"`
	Parameters map[string]any              `json:"parameters,omitempty"`
	Messages   []CreateModelRequestMessage `json:"messages,omitempty"`
	Quantize   string                      `json:"quantize,omitempty"`
	Stream     *bool                       `json:"stream,omitempty"`
}

type CreateModelRequestMessage struct {
	Role      string                              `json:"role"`
	Content   string                              `json:"content"`
	Images    []string                            `json:"images,omitempty"`
	ToolCalls []CreateModelRequestMessageToolCall `json:"tool_calls,omitempty"`
}

type CreateModelRequestMessageToolCall struct {
	Function *CreateModelRequestMessageToolCallFunction `json:"function,omitempty"`
}

type CreateModelRequestMessageToolCallFunction struct {
	Name        string         `json:"name"`
	Description string         `json:"description,omitempty"`
	Arguments   map[string]any `json:"arguments,omitempty"`
}

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

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

func (o Ollama) CreateModel(reqBody CreateModelRequest) (CreateModelResponse, error) {
	reqBody.Stream = PtrOf(false)

	reqBodyBytes, err := json.Marshal(reqBody)
	if err != nil {
		return CreateModelResponse{}, err
	}

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

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

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

func (o Ollama) CreateModelStream(reqBody CreateModelRequest, onChunk func(chunk CreateModelResponseStream)) error {
	reqBody.Stream = PtrOf(true)

	reqBodyBytes, err := json.Marshal(reqBody)
	if err != nil {
		return err
	}

	req, err := http.NewRequest(http.MethodPost, fmt.Sprintf("%s/create", 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 CreateModelResponseStream
		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
}