package main

import (
	"os"
	"path/filepath"
	"strings"
)

const defaultBalanceURL = "https://api.deepseek.com/user/balance"

// Config is the fully-resolved runtime configuration. Values are loaded with
// precedence: process environment > .env file > built-in default.
type Config struct {
	APIKey     string
	BalanceURL string

	// Harness daemon settings; consumed by the harness feature in a later step.
	Harness harnessConfig
}

// LoadConfig resolves configuration from the .env file in dir (best-effort),
// overlaid with process environment variables, then defaults.
func LoadConfig(dir string) Config {
	dotenv := readDotEnv(filepath.Join(dir, ".env"))

	cfg := Config{
		BalanceURL: defaultBalanceURL,
		Harness: harnessConfig{
			Enabled:    true,
			Command:    "npx --yes @deepseek-ai/dsh web",
			URL:        "http://127.0.0.1:3080",
			StartDelay: 15,
			LogFile:    "harness.log",
		},
	}

	cfg.APIKey = firstNonEmpty(os.Getenv("DEEPSEEK_API_KEY"), dotenv["DEEPSEEK_API_KEY"])
	if v := firstNonEmpty(os.Getenv("DEEPSEEK_BALANCE_URL"), dotenv["DEEPSEEK_BALANCE_URL"]); v != "" {
		cfg.BalanceURL = v
	}
	return cfg
}

func firstNonEmpty(values ...string) string {
	for _, v := range values {
		if v != "" {
			return v
		}
	}
	return ""
}

// readDotEnv parses a simple KEY=VALUE file. Missing files yield an empty map.
// Lines are trimmed; '#' starts a comment; quotes are stripped from values.
func readDotEnv(path string) map[string]string {
	data, err := os.ReadFile(path)
	if err != nil {
		return nil
	}
	m := make(map[string]string)
	for _, raw := range strings.Split(string(data), "\n") {
		line := strings.TrimSpace(raw)
		if line == "" || line[0] == '#' {
			continue
		}
		eq := strings.IndexByte(line, '=')
		if eq < 1 {
			continue
		}
		k := strings.TrimSpace(line[:eq])
		v := strings.TrimSpace(line[eq+1:])
		m[k] = strings.Trim(v, `"'`)
	}
	return m
}