// Package store persists workspace-level PR review confirmation state.
//
// Confirmations live in <workspace>/.spx/pr-review-confirmed.json as a
// map[string][]string. File-level confirmations use key "<issueNumber>:<sha>"
// and hold the confirmed file paths of that commit; commit-level confirmations
// use key "<issueNumber>:commits" and hold the confirmed commit SHAs. Directories
// are not tracked separately. A missing or malformed file reads as empty.
package store

import (
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"strconv"

	"superwork-tui/internal/config"
)

type confirmedMap = map[string][]string

func confirmedFile(workspaceRoot string) string {
	return filepath.Join(config.SpxDir(workspaceRoot), "pr-review-confirmed.json")
}

func fileKey(issueNumber int, sha string) string {
	return strconv.Itoa(issueNumber) + ":" + sha
}

func commitsKey(issueNumber int) string {
	return strconv.Itoa(issueNumber) + ":commits"
}

// readMap returns the whole confirmation map. A missing or unparseable file
// reads as an empty map rather than an error.
func readMap(workspaceRoot string) confirmedMap {
	raw, err := os.ReadFile(confirmedFile(workspaceRoot))
	if err != nil {
		return confirmedMap{}
	}
	var parsed confirmedMap
	if err := json.Unmarshal(raw, &parsed); err != nil {
		return confirmedMap{}
	}
	return parsed
}

// writeMap persists the confirmation map, creating .spx if needed.
func writeMap(workspaceRoot string, m confirmedMap) error {
	if err := os.MkdirAll(config.SpxDir(workspaceRoot), 0o755); err != nil {
		return fmt.Errorf("create .spx dir: %w", err)
	}
	data, err := json.MarshalIndent(m, "", "  ")
	if err != nil {
		return fmt.Errorf("marshal confirmations: %w", err)
	}
	if err := os.WriteFile(confirmedFile(workspaceRoot), append(data, '\n'), 0o644); err != nil {
		return fmt.Errorf("write confirmations: %w", err)
	}
	return nil
}

// ReadConfirmed returns the confirmed file paths for a (issueNumber, sha) commit.
func ReadConfirmed(workspaceRoot string, issueNumber int, sha string) ([]string, error) {
	return readMap(workspaceRoot)[fileKey(issueNumber, sha)], nil
}

// WriteConfirmed sets the confirmed file paths for a (issueNumber, sha) commit.
// An empty slice deletes the key.
func WriteConfirmed(workspaceRoot string, issueNumber int, sha string, paths []string) error {
	m := readMap(workspaceRoot)
	key := fileKey(issueNumber, sha)
	if len(paths) > 0 {
		m[key] = paths
	} else {
		delete(m, key)
	}
	return writeMap(workspaceRoot, m)
}

// ReadConfirmedCommits returns the confirmed commit SHAs for an issue.
func ReadConfirmedCommits(workspaceRoot string, issueNumber int) ([]string, error) {
	return readMap(workspaceRoot)[commitsKey(issueNumber)], nil
}

// WriteConfirmedCommits sets the confirmed commit SHAs for an issue.
// An empty slice deletes the key.
func WriteConfirmedCommits(workspaceRoot string, issueNumber int, shas []string) error {
	m := readMap(workspaceRoot)
	key := commitsKey(issueNumber)
	if len(shas) > 0 {
		m[key] = shas
	} else {
		delete(m, key)
	}
	return writeMap(workspaceRoot, m)
}