package main

import (
	"context"
	"encoding/json"
	"errors"
	"flag"
	"fmt"
	"io"
	"net/http"
	"os"
	"strings"
	"time"

	"data-terminal-cloud/internal/agenteval"
)

func main() {
	os.Exit(run(os.Args[1:], os.Stdout, os.Stderr))
}

func run(args []string, stdout, stderr io.Writer) int {
	flags := flag.NewFlagSet("agent-eval-collect", flag.ContinueOnError)
	flags.SetOutput(stderr)
	suitePath := flags.String("suite", "", "评测集JSON路径")
	manifestPath := flags.String("manifest", "", "用例、通话和脱敏评分卡映射JSON路径")
	outputPath := flags.String("out", "", "观测结果输出路径；省略时输出到stdout")
	apiBaseURL := flags.String("api", "http://127.0.0.1:58080", "SaaS API基础地址")
	tokenFile := flags.String("access-token-file", "", "OIDC访问令牌文件；省略时读取AGENT_EVAL_ACCESS_TOKEN")
	if err := flags.Parse(args); err != nil {
		return 2
	}
	if *suitePath == "" || *manifestPath == "" || flags.NArg() != 0 {
		fmt.Fprintln(stderr, "usage: agent-eval-collect -suite <suite.json> -manifest <manifest.json> [-api <url>] [-access-token-file <path>] [-out <observations.json>]")
		return 2
	}
	var suite agenteval.Suite
	if err := decodeFile(*suitePath, &suite); err != nil {
		fmt.Fprintf(stderr, "读取评测集失败: %v\n", err)
		return 2
	}
	var manifest agenteval.CollectionManifest
	if err := decodeFile(*manifestPath, &manifest); err != nil {
		fmt.Fprintf(stderr, "读取采集清单失败: %v\n", err)
		return 2
	}
	token, err := readToken(*tokenFile)
	if err != nil {
		fmt.Fprintf(stderr, "读取访问令牌失败: %v\n", err)
		return 2
	}
	collector, err := agenteval.NewCollector(*apiBaseURL, token, &http.Client{Timeout: 15 * time.Second})
	if err != nil {
		fmt.Fprintf(stderr, "创建采集器失败: %v\n", err)
		return 2
	}
	runResult, err := collector.Collect(context.Background(), suite, manifest)
	if err != nil {
		fmt.Fprintf(stderr, "采集评测观测失败: %v\n", err)
		return 1
	}
	encoded, err := json.MarshalIndent(runResult, "", "  ")
	if err != nil {
		fmt.Fprintf(stderr, "生成观测文件失败: %v\n", err)
		return 2
	}
	encoded = append(encoded, '\n')
	if *outputPath == "" {
		if _, err = stdout.Write(encoded); err != nil {
			fmt.Fprintf(stderr, "输出观测文件失败: %v\n", err)
			return 2
		}
	} else if err = os.WriteFile(*outputPath, encoded, 0o600); err != nil {
		fmt.Fprintf(stderr, "写入观测文件失败: %v\n", err)
		return 2
	} else {
		fmt.Fprintf(stdout, "已采集%d个用例：%s\n", len(runResult.Observations), *outputPath)
	}
	return 0
}

func readToken(path string) (string, error) {
	if strings.TrimSpace(path) == "" {
		value := strings.TrimSpace(os.Getenv("AGENT_EVAL_ACCESS_TOKEN"))
		if value == "" {
			return "", errors.New("set AGENT_EVAL_ACCESS_TOKEN or -access-token-file")
		}
		return value, nil
	}
	content, err := os.ReadFile(path)
	if err != nil {
		return "", err
	}
	value := strings.TrimSpace(string(content))
	if value == "" || strings.ContainsAny(value, "\r\n\x00") {
		return "", errors.New("token file must contain one non-empty line")
	}
	return value, nil
}

func decodeFile(path string, target any) error {
	file, err := os.Open(path)
	if err != nil {
		return err
	}
	defer file.Close()
	decoder := json.NewDecoder(file)
	decoder.DisallowUnknownFields()
	if err = decoder.Decode(target); err != nil {
		return err
	}
	var trailing any
	if err = decoder.Decode(&trailing); !errors.Is(err, io.EOF) {
		if err == nil {
			return errors.New("JSON文件包含多个顶层值")
		}
		return err
	}
	return nil
}