package javaanalyzer

import (
	"context"
	"regexp"
	"strings"

	contractevents "bit.admedia.com/scm/ad/adpilot-indexing-code-parser.com/internal/contracts/events"
	"bit.admedia.com/scm/ad/adpilot-indexing-code-parser.com/internal/contracts/graph"
	"bit.admedia.com/scm/ad/adpilot-indexing-code-parser.com/internal/service/parser/analyzers/common"
	"bit.admedia.com/scm/ad/adpilot-indexing-code-parser.com/internal/service/parser/analyzers/detectors"
)

type Analyzer struct {
	detectors *detectors.Registry
}

func NewAnalyzer(det *detectors.Registry) *Analyzer {
	if det == nil {
		det = detectors.DefaultRegistry()
	}
	return &Analyzer{detectors: det}
}

func (a *Analyzer) SupportedLanguages() []string {
	return []string{"java"}
}

func (a *Analyzer) ParseFile(ctx context.Context, source []byte, filePath, language string) (*graph.Artifact, []contractevents.CodeChunk, error) {
	_ = ctx
	b := common.NewBuilder(filePath, "java")
	lines := common.Lines(source)

	importPattern := regexp.MustCompile(`^import\s+(?:static\s+)?([\w.]+)`)
	packagePattern := regexp.MustCompile(`^package\s+([\w.]+)`)
	classPattern := regexp.MustCompile(`(?:public\s+|private\s+|protected\s+)?(?:abstract\s+|final\s+)?(?:class|interface|enum|record)\s+([A-Za-z_][A-Za-z0-9_]*)`)
	methodPattern := regexp.MustCompile(`(?:public|private|protected|static|\s)+[\w<>\[\],\s]+\s+([A-Za-z_][A-Za-z0-9_]*)\s*\([^;]*\)\s*(?:throws\s+[\w.\s,]+)?\s*\{`)

	for i, line := range lines {
		trimmed := strings.TrimSpace(line)
		if m := packagePattern.FindStringSubmatch(trimmed); len(m) > 1 {
			b.AddImport(m[1], i+1)
		}
		if m := importPattern.FindStringSubmatch(trimmed); len(m) > 1 {
			b.AddImport(m[1], i+1)
		}
		if m := classPattern.FindStringSubmatch(trimmed); len(m) > 1 {
			end := findBraceBlockEnd(lines, i)
			typeKind := "class"
			if strings.Contains(trimmed, "interface") {
				typeKind = "interface"
			}
			b.AddSymbol(m[1], contractevents.SymbolTypeType, i+1, end, map[string]string{"type_kind": typeKind})
		}
		if m := methodPattern.FindStringSubmatch(trimmed); len(m) > 1 {
			if m[1] != "if" && m[1] != "for" && m[1] != "while" {
				end := findBraceBlockEnd(lines, i)
				b.AddSymbol(m[1], contractevents.SymbolTypeMethod, i+1, end, nil)
			}
		}
	}

	a.detectors.ApplyAll(detectors.Context{
		Source:   source,
		FilePath: filePath,
		Language: "java",
		Builder:  b,
	})

	b.EnsureLineWindowChunks(source)

	return b.Artifact(), b.Chunks(), nil
}

func findBraceBlockEnd(lines []string, start int) int {
	depth := 0
	started := false
	for i := start; i < len(lines); i++ {
		for _, ch := range lines[i] {
			switch ch {
			case '{':
				depth++
				started = true
			case '}':
				depth--
				if started && depth == 0 {
					return i + 1
				}
			}
		}
	}
	return start + 1
}