package engine

import (
	"fmt"
	"os"
	"path/filepath"
	"testing"

	"git.dern.ovh/infrastructure/caddy-opnsense-blocker/internal/config"
	"git.dern.ovh/infrastructure/caddy-opnsense-blocker/internal/model"
)

func TestEvaluatorManualOverridesTakePriority(t *testing.T) {
	t.Parallel()

	profile := loadProfile(t, `
auto_block: true
block_unexpected_posts: true
block_php_paths: true
suspicious_path_prefixes:
  - /wp-admin
`)
	evaluator := NewEvaluator()
	record := model.AccessLogRecord{ClientIP: "203.0.113.10", Status: 404, Method: "GET", Path: "/wp-admin/install.php", UserAgent: "curl/8.0"}

	if decision := evaluator.Evaluate(record, profile, model.ManualOverrideForceAllow); decision.Action != model.DecisionActionAllow {
		t.Fatalf("expected manual allow to win, got %+v", decision)
	}
	if decision := evaluator.Evaluate(record, profile, model.ManualOverrideForceBlock); decision.Action != model.DecisionActionBlock {
		t.Fatalf("expected manual block to win, got %+v", decision)
	}
}

func TestEvaluatorBlocksSuspiciousRequests(t *testing.T) {
	t.Parallel()

	profile := loadProfile(t, `
auto_block: true
block_unexpected_posts: true
block_php_paths: true
allowed_post_paths:
  - /search
suspicious_path_prefixes:
  - /wp-admin
`)
	evaluator := NewEvaluator()
	record := model.AccessLogRecord{ClientIP: "203.0.113.11", Status: 404, Method: "POST", Path: "/wp-admin/install.php", UserAgent: "curl/8.0"}

	decision := evaluator.Evaluate(record, profile, model.ManualOverrideNone)
	if decision.Action != model.DecisionActionBlock {
		t.Fatalf("expected block decision, got %+v", decision)
	}
	if len(decision.Reasons) < 2 {
		t.Fatalf("expected multiple blocking reasons, got %+v", decision)
	}
}

func TestEvaluatorAllowsExcludedCIDRAndKnownAgents(t *testing.T) {
	t.Parallel()

	profile := loadProfile(t, `
auto_block: true
excluded_cidrs:
  - 10.0.0.0/8
known_agents:
  - name: friendly-bot
    decision: allow
    user_agent_prefixes:
      - FriendlyBot/
`)
	evaluator := NewEvaluator()

	excluded := model.AccessLogRecord{ClientIP: "10.0.0.5", Status: 404, Method: "GET", Path: "/wp-login.php", UserAgent: "curl/8.0"}
	if decision := evaluator.Evaluate(excluded, profile, model.ManualOverrideNone); decision.Action != model.DecisionActionAllow {
		t.Fatalf("expected excluded cidr to be allowed, got %+v", decision)
	}

	knownAgent := model.AccessLogRecord{ClientIP: "203.0.113.12", Status: 404, Method: "GET", Path: "/wp-login.php", UserAgent: "FriendlyBot/2.0"}
	if decision := evaluator.Evaluate(knownAgent, profile, model.ManualOverrideNone); decision.Action != model.DecisionActionAllow {
		t.Fatalf("expected known agent to be allowed, got %+v", decision)
	}
}

func TestEvaluatorReturnsReviewWhenAutoBlockIsDisabled(t *testing.T) {
	t.Parallel()

	profile := loadProfile(t, `
auto_block: false
block_unexpected_posts: true
suspicious_path_prefixes:
  - /admin
`)
	evaluator := NewEvaluator()
	record := model.AccessLogRecord{ClientIP: "203.0.113.13", Status: 404, Method: "POST", Path: "/admin", UserAgent: "curl/8.0"}

	decision := evaluator.Evaluate(record, profile, model.ManualOverrideNone)
	if decision.Action != model.DecisionActionReview {
		t.Fatalf("expected review decision, got %+v", decision)
	}
}

func loadProfile(t *testing.T, profileSnippet string) config.ProfileConfig {
	t.Helper()
	tempDir := t.TempDir()
	configPath := filepath.Join(tempDir, "config.yaml")
	payload := fmt.Sprintf(`profiles:
  main:%s
sources:
  - name: main
    path: %s/access.json
    profile: main
`, indent(profileSnippet, 4), tempDir)
	if err := os.WriteFile(configPath, []byte(payload), 0o600); err != nil {
		t.Fatalf("write config file: %v", err)
	}
	cfg, err := config.Load(configPath)
	if err != nil {
		t.Fatalf("load config: %v", err)
	}
	return cfg.Profiles["main"]
}

func indent(value string, spaces int) string {
	padding := ""
	for range spaces {
		padding += " "
	}
	lines := []byte(value)
	_ = lines
	var output string
	for _, line := range splitLines(value) {
		trimmed := line
		if trimmed == "" {
			output += "\n"
			continue
		}
		output += "\n" + padding + trimmed
	}
	return output
}

func splitLines(value string) []string {
	var lines []string
	start := 0
	for index, character := range value {
		if character == '\n' {
			lines = append(lines, value[start:index])
			start = index + 1
		}
	}
	lines = append(lines, value[start:])
	return lines
}