import type { Plugin } from "@opencode-ai/plugin";
import { tool } from "@opencode-ai/plugin/tool";
import {
    EnvSitter,
    addEnvFileKey,
    annotateEnvFile,
    copyEnvFileKeys,
    deleteEnvFileKeys,
    formatEnvFile,
    setEnvFileKey,
    unsetEnvFileKey,
    validateEnvFile,
} from "envsitter";
import path from "node:path";

function normalizePath(input: string): string {
    return input.replace(/\\/g, "/");
}

function isDotEnvExamplePath(input: string): boolean {
    return /(^|\/)\.env\.example$/.test(normalizePath(input));
}

function isSensitiveDotEnvPath(input: string): boolean {
    const normalized = normalizePath(input);
    if (isDotEnvExamplePath(normalized)) return false;
    return /(^|\/)\.env($|\.)/.test(normalized);
}

function isDotEnvishPath(input: string): boolean {
    const normalized = normalizePath(input);
    return isDotEnvExamplePath(normalized) || isSensitiveDotEnvPath(normalized);
}

function isEnvSitterPepperPath(input: string): boolean {
    const normalized = normalizePath(input);
    return /(^|\/)\.envsitter\/pepper$/.test(normalized);
}

function stripAtPrefix(input: string): string {
    return input.trim().replace(/^@+/, "");
}

function parseUserRegExp(input: string): RegExp {
    const trimmed = input.trim();
    if (!trimmed.startsWith("/")) return new RegExp(trimmed);

    let lastSlashIndex = -1;
    for (let i = trimmed.length - 1; i >= 1; i -= 1) {
        if (trimmed[i] !== "/") continue;

        let backslashCount = 0;
        for (let j = i - 1; j >= 0 && trimmed[j] === "\\"; j -= 1) {
            backslashCount += 1;
        }

        const isEscaped = backslashCount % 2 === 1;
        if (!isEscaped) {
            lastSlashIndex = i;
            break;
        }
    }

    if (lastSlashIndex === -1) {
        throw new Error("Invalid regex literal; expected a closing `/`.");
    }

    const body = trimmed.slice(1, lastSlashIndex);
    const flags = trimmed.slice(lastSlashIndex + 1);
    if (!/^[a-z]*$/.test(flags)) {
        throw new Error("Invalid regex literal flags; expected only letters (e.g. `/abc/i`).");
    }

    return new RegExp(body, flags);
}

function resolveCandidate(params: { candidate?: string; candidateEnvVar?: string }): string {
    if (typeof params.candidate === "string" && params.candidate.length > 0) return params.candidate;

    if (typeof params.candidateEnvVar === "string" && params.candidateEnvVar.length > 0) {
        const value = process.env[params.candidateEnvVar];
        if (typeof value === "string" && value.length > 0) return value;
        throw new Error(`Env var \`${params.candidateEnvVar}\` was not set.`);
    }

    throw new Error("Candidate is required for this operation. Provide `candidate` or `candidateEnvVar`.");
}

function getFilePathFromArgs(args: unknown): string | undefined {
    if (!args || typeof args !== "object") return;
    const record = args as Record<string, unknown>;

    const candidates: Array<unknown> = [record.filePath, record.path, record.file_path];

    const found = candidates.find((value) => typeof value === "string") as string | undefined;
    return found ? stripAtPrefix(found) : undefined;
}

function resolveDotEnvPath(params: {
    worktree: string;
    directory: string;
    filePath: string;
}): { absolutePath: string; displayPath: string } {
    const normalized = normalizePath(params.filePath);

    if (isEnvSitterPepperPath(normalized)) {
        throw new Error("Access to `.envsitter/pepper` is blocked.");
    }

    if (!isDotEnvishPath(normalized)) {
        throw new Error("Only `.env`-style paths are allowed (e.g. `.env`, `.env.local`, `.env.example`).");
    }

    const absolutePath = path.resolve(params.directory, normalized);
    const relativeToWorktree = path.relative(params.worktree, absolutePath);
    if (relativeToWorktree.startsWith("..") || path.isAbsolute(relativeToWorktree)) {
        throw new Error("EnvSitter tools only operate on files inside the current project.");
    }

    return { absolutePath, displayPath: relativeToWorktree };
}

export const EnvSitterGuard: Plugin = async ({ directory, worktree }) => {
    const matchOps = [
        "exists",
        "is_empty",
        "is_equal",
        "partial_match_prefix",
        "partial_match_suffix",
        "partial_match_regex",
        "is_number",
        "is_boolean",
        "is_string",
    ] as const;

    const scanDetections = ["jwt", "url", "base64"] as const;

    return {
        tool: {
            envsitter_keys: tool({
                description: "List keys in a .env file (never returns values).",
                args: {
                    filePath: tool.schema.string().optional(),
                    filterRegex: tool.schema.string().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const es = EnvSitter.fromDotenvFile(resolved.absolutePath);
                    const keys = await es.listKeys(
                        args.filterRegex
                            ? {
                                  filter: parseUserRegExp(args.filterRegex),
                              }
                            : undefined,
                    );

                    return JSON.stringify({ file: resolved.displayPath, keys }, null, 2);
                },
            }),
            envsitter_fingerprint: tool({
                description: "Compute a deterministic fingerprint for a single key (never returns the value).",
                args: {
                    filePath: tool.schema.string().optional(),
                    key: tool.schema.string(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const es = EnvSitter.fromDotenvFile(resolved.absolutePath);
                    const result = await es.fingerprintKey(args.key);

                    return JSON.stringify({ file: resolved.displayPath, key: args.key, result }, null, 2);
                },
            }),
            envsitter_match: tool({
                description:
                    "Match key values without printing them. Supports existence/shape checks and outside-in candidate matching.",
                args: {
                    filePath: tool.schema.string().optional(),
                    op: tool.schema.enum(matchOps).optional(),
                    key: tool.schema.string().optional(),
                    keys: tool.schema.array(tool.schema.string()).optional(),
                    allKeys: tool.schema.boolean().optional(),
                    candidate: tool.schema.string().optional(),
                    candidateEnvVar: tool.schema.string().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const op = args.op ?? "is_equal";
                    const es = EnvSitter.fromDotenvFile(resolved.absolutePath);

                    let isEqualCandidate: string | undefined;

                    const matcher = (() => {
                        if (op === "exists") return { op } as const;
                        if (op === "is_empty") return { op } as const;
                        if (op === "is_number") return { op } as const;
                        if (op === "is_boolean") return { op } as const;
                        if (op === "is_string") return { op } as const;

                        const candidate = resolveCandidate({
                            candidate: args.candidate,
                            candidateEnvVar: args.candidateEnvVar,
                        });

                        if (op === "is_equal") {
                            isEqualCandidate = candidate;
                            return { op, candidate } as const;
                        }

                        if (op === "partial_match_prefix") {
                            return { op, prefix: candidate } as const;
                        }

                        if (op === "partial_match_suffix") {
                            return { op, suffix: candidate } as const;
                        }

                        if (op === "partial_match_regex") {
                            return { op, regex: parseUserRegExp(candidate) } as const;
                        }

                        throw new Error(`Unsupported op: ${op}`);
                    })();

                    const key = args.key;
                    const keys = args.keys;
                    const allKeys = args.allKeys === true;

                    const selectorCount =
                        Number(typeof key === "string") + Number(Array.isArray(keys) && keys.length > 0) + Number(allKeys);
                    if (selectorCount !== 1) {
                        throw new Error("Provide exactly one of: `key`, `keys`, or `allKeys: true`. ");
                    }

                    if (typeof key === "string") {
                        const match =
                            matcher.op === "is_equal" && typeof isEqualCandidate === "string"
                                ? await es.matchCandidate(key, isEqualCandidate)
                                : await es.matchKey(key, matcher);
                        return JSON.stringify({ file: resolved.displayPath, key, op: matcher.op, match }, null, 2);
                    }

                    if (Array.isArray(keys) && keys.length > 0) {
                        const matches =
                            matcher.op === "is_equal" && typeof isEqualCandidate === "string"
                                ? await es.matchCandidateBulk(keys, isEqualCandidate)
                                : await es.matchKeyBulk(keys, matcher);
                        return JSON.stringify({ file: resolved.displayPath, op: matcher.op, matches }, null, 2);
                    }

                    const matches =
                        matcher.op === "is_equal" && typeof isEqualCandidate === "string"
                            ? await es.matchCandidateAll(isEqualCandidate)
                            : await es.matchKeyAll(matcher);
                    return JSON.stringify({ file: resolved.displayPath, op: matcher.op, matches }, null, 2);
                },
            }),
            envsitter_match_by_key: tool({
                description: "Bulk match candidates-by-key without printing values (returns booleans only).",
                args: {
                    filePath: tool.schema.string().optional(),
                    candidatesByKey: tool.schema.record(tool.schema.string(), tool.schema.string()).optional(),
                    candidatesByKeyJson: tool.schema.string().optional(),
                    candidatesByKeyEnvVar: tool.schema.string().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const fromRecord = args.candidatesByKey;
                    const fromJson = args.candidatesByKeyJson;
                    const fromEnvVar = args.candidatesByKeyEnvVar;

                    const selectorCount = Number(!!fromRecord) + Number(!!fromJson) + Number(!!fromEnvVar);
                    if (selectorCount !== 1) {
                        throw new Error(
                            "Provide exactly one of: `candidatesByKey`, `candidatesByKeyJson`, or `candidatesByKeyEnvVar`.",
                        );
                    }

                    let candidatesByKey: Record<string, string>;

                    if (fromRecord) {
                        candidatesByKey = fromRecord;
                    } else {
                        const json =
                            typeof fromJson === "string"
                                ? fromJson
                                : (() => {
                                      const envVarName = fromEnvVar as string;
                                      const value = process.env[envVarName];
                                      if (typeof value !== "string") throw new Error(`Env var \`${envVarName}\` was not set.`);
                                      return value;
                                  })();

                        let parsed: unknown;
                        try {
                            parsed = JSON.parse(json);
                        } catch {
                            throw new Error("Invalid candidates JSON; expected an object mapping key -> candidate string.");
                        }

                        if (!parsed || typeof parsed !== "object" || Array.isArray(parsed)) {
                            throw new Error("Invalid candidates JSON; expected an object mapping key -> candidate string.");
                        }

                        const record = parsed as Record<string, unknown>;
                        const normalized: Record<string, string> = {};
                        for (const [key, value] of Object.entries(record)) {
                            if (typeof value !== "string") {
                                throw new Error("Invalid candidates JSON; expected every value to be a string.");
                            }
                            normalized[key] = value;
                        }
                        candidatesByKey = normalized;
                    }

                    const es = EnvSitter.fromDotenvFile(resolved.absolutePath);
                    const matches = await es.matchCandidatesByKey(candidatesByKey);

                    return JSON.stringify({ file: resolved.displayPath, matches }, null, 2);
                },
            }),
            envsitter_scan: tool({
                description: "Scan value shapes (jwt/url/base64) without printing values.",
                args: {
                    filePath: tool.schema.string().optional(),
                    detect: tool.schema.array(tool.schema.enum(scanDetections)).optional(),
                    keysFilterRegex: tool.schema.string().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const es = EnvSitter.fromDotenvFile(resolved.absolutePath);
                    const findings = await es.scan({
                        detect: args.detect,
                        keysFilter: args.keysFilterRegex ? parseUserRegExp(args.keysFilterRegex) : undefined,
                    });

                    return JSON.stringify({ file: resolved.displayPath, findings }, null, 2);
                },
            }),
            envsitter_validate: tool({
                description: "Validate dotenv syntax (never returns values).",
                args: {
                    filePath: tool.schema.string().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await validateEnvFile(resolved.absolutePath);
                    return JSON.stringify({ file: resolved.displayPath, ok: result.ok, issues: result.issues }, null, 2);
                },
            }),
            envsitter_copy: tool({
                description:
                    "Copy keys between dotenv files safely (no values in output). Dry-run unless `write: true`.",
                args: {
                    from: tool.schema.string(),
                    to: tool.schema.string(),
                    keys: tool.schema.array(tool.schema.string()).optional(),
                    includeRegex: tool.schema.string().optional(),
                    excludeRegex: tool.schema.string().optional(),
                    rename: tool.schema.string().optional(),
                    onConflict: tool.schema.enum(["error", "skip", "overwrite"] as const).optional(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolvedFrom = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.from,
                    });

                    const resolvedTo = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.to,
                    });

                    if (typeof args.rename === "string" && args.rename.trim().length === 0) {
                        throw new Error("Invalid `rename`; expected a non-empty string like `A=B,C=D`. ");
                    }

                    const result = await copyEnvFileKeys({
                        from: resolvedFrom.absolutePath,
                        to: resolvedTo.absolutePath,
                        keys: Array.isArray(args.keys) && args.keys.length > 0 ? args.keys : undefined,
                        include: args.includeRegex ? parseUserRegExp(args.includeRegex) : undefined,
                        exclude: args.excludeRegex ? parseUserRegExp(args.excludeRegex) : undefined,
                        rename: args.rename,
                        onConflict: args.onConflict,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            from: resolvedFrom.displayPath,
                            to: resolvedTo.displayPath,
                            onConflict: result.onConflict,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                            plan: result.plan,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_format: tool({
                description: "Format/reorder a dotenv file (no values in output). Dry-run unless `write: true`.",
                args: {
                    filePath: tool.schema.string().optional(),
                    mode: tool.schema.enum(["sections", "global"] as const).optional(),
                    sort: tool.schema.enum(["alpha", "none"] as const).optional(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await formatEnvFile({
                        file: resolved.absolutePath,
                        mode: args.mode,
                        sort: args.sort,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            mode: result.mode,
                            sort: result.sort,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_reorder: tool({
                description: "Alias for envsitter_format.",
                args: {
                    filePath: tool.schema.string().optional(),
                    mode: tool.schema.enum(["sections", "global"] as const).optional(),
                    sort: tool.schema.enum(["alpha", "none"] as const).optional(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await formatEnvFile({
                        file: resolved.absolutePath,
                        mode: args.mode,
                        sort: args.sort,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            mode: result.mode,
                            sort: result.sort,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_annotate: tool({
                description: "Annotate a dotenv key with a comment (no values in output). Dry-run unless `write: true`.",
                args: {
                    filePath: tool.schema.string().optional(),
                    key: tool.schema.string(),
                    comment: tool.schema.string(),
                    line: tool.schema.number().int().optional(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    if (args.comment.trim().length === 0) {
                        throw new Error("Comment must be a non-empty string.");
                    }

                    const result = await annotateEnvFile({
                        file: resolved.absolutePath,
                        key: args.key,
                        comment: args.comment,
                        line: args.line,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            key: result.key,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                            plan: result.plan,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_add: tool({
                description:
                    "Add a new key to a dotenv file (fails if key already exists). Dry-run unless `write: true`.",
                args: {
                    filePath: tool.schema.string().optional(),
                    key: tool.schema.string(),
                    value: tool.schema.string(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await addEnvFileKey({
                        file: resolved.absolutePath,
                        key: args.key,
                        value: args.value,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            key: result.key,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                            plan: result.plan,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_set: tool({
                description:
                    "Set a key's value in a dotenv file (creates if missing, updates if exists). Dry-run unless `write: true`.",
                args: {
                    filePath: tool.schema.string().optional(),
                    key: tool.schema.string(),
                    value: tool.schema.string(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await setEnvFileKey({
                        file: resolved.absolutePath,
                        key: args.key,
                        value: args.value,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            key: result.key,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                            plan: result.plan,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_unset: tool({
                description:
                    "Unset a key's value in a dotenv file (sets to empty string, keeps the key). Dry-run unless `write: true`.",
                args: {
                    filePath: tool.schema.string().optional(),
                    key: tool.schema.string(),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await unsetEnvFileKey({
                        file: resolved.absolutePath,
                        key: args.key,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            key: result.key,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                            plan: result.plan,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_delete: tool({
                description:
                    "Delete key(s) from a dotenv file entirely (removes the line). Dry-run unless `write: true`.",
                args: {
                    filePath: tool.schema.string().optional(),
                    keys: tool.schema.array(tool.schema.string()),
                    write: tool.schema.boolean().optional(),
                },
                async execute(args) {
                    const resolved = resolveDotEnvPath({
                        worktree,
                        directory,
                        filePath: args.filePath ?? ".env",
                    });

                    const result = await deleteEnvFileKeys({
                        file: resolved.absolutePath,
                        keys: args.keys,
                        write: args.write === true,
                    });

                    return JSON.stringify(
                        {
                            file: resolved.displayPath,
                            keys: result.keys,
                            willWrite: result.willWrite,
                            wrote: result.wrote,
                            hasChanges: result.hasChanges,
                            issues: result.issues,
                            plan: result.plan,
                        },
                        null,
                        2,
                    );
                },
            }),
            envsitter_help: tool({
                description:
                    "Get comprehensive help on all EnvSitter tools. Call this to understand how to safely work with .env files without exposing secrets.",
                args: {
                    topic: tool.schema
                        .enum([
                            "overview",
                            "reading",
                            "matching",
                            "mutations",
                            "file_ops",
                            "all",
                        ] as const)
                        .optional(),
                },
                async execute(args) {
                    const topic = args.topic ?? "all";

                    const overview = `
## EnvSitter Tools Overview

EnvSitter provides safe .env file operations that NEVER expose secret values.
All tools return keys, booleans, line numbers, and operation plans only.

### Why Use EnvSitter?
- Direct reading of .env files is BLOCKED to prevent secret leaks
- These tools let you inspect, validate, and modify .env files safely
- File modifications are dry-run by default; use \`write: true\` to apply

### Tool Categories
- **Reading**: envsitter_keys, envsitter_fingerprint, envsitter_scan
- **Matching**: envsitter_match, envsitter_match_by_key
- **Mutations**: envsitter_add, envsitter_set, envsitter_unset, envsitter_delete
- **File Ops**: envsitter_validate, envsitter_copy, envsitter_format, envsitter_annotate
`;

                    const reading = `
## Reading Tools (never return values)

### envsitter_keys
List all keys in a .env file.
\`\`\`json
{ "filePath": ".env", "filterRegex": "/^API_/" }
\`\`\`
Returns: \`{ file, keys: string[] }\`

### envsitter_fingerprint
Get a deterministic fingerprint of a key's value (for comparison/auditing).
\`\`\`json
{ "filePath": ".env", "key": "DATABASE_URL" }
\`\`\`
Returns: \`{ file, key, result: { algorithm, fingerprint, length } }\`

### envsitter_scan
Detect value shapes (JWT, URL, base64) without revealing values.
\`\`\`json
{ "filePath": ".env", "detect": ["jwt", "url", "base64"], "keysFilterRegex": "/TOKEN/" }
\`\`\`
Returns: \`{ file, findings: [{ key, detections }] }\`
`;

                    const matching = `
## Matching Tools (return booleans only)

### envsitter_match
Check if a key's value matches criteria without seeing the value.

**Operations** (op parameter):
- \`exists\`: key is present
- \`is_empty\`: value is empty string
- \`is_equal\`: matches candidate exactly (provide \`candidate\` or \`candidateEnvVar\`)
- \`partial_match_prefix\`: value starts with candidate
- \`partial_match_suffix\`: value ends with candidate
- \`partial_match_regex\`: value matches regex pattern
- \`is_number\`: value is numeric
- \`is_boolean\`: value is true/false
- \`is_string\`: value is neither number nor boolean

**Selectors** (provide exactly one):
- \`key\`: single key
- \`keys\`: array of keys
- \`allKeys: true\`: all keys in file

\`\`\`json
{ "filePath": ".env", "key": "NODE_ENV", "op": "is_equal", "candidate": "production" }
{ "filePath": ".env", "keys": ["API_KEY", "SECRET"], "op": "exists" }
{ "filePath": ".env", "allKeys": true, "op": "is_empty" }
\`\`\`

### envsitter_match_by_key
Bulk match different candidates against different keys.
\`\`\`json
{ "filePath": ".env", "candidatesByKey": { "API_KEY": "sk-xxx", "DB_PASS": "secret123" } }
\`\`\`
Returns: \`{ file, matches: [{ key, match: boolean }] }\`
`;

                    const mutations = `
## Mutation Tools (modify .env files safely)

All mutation tools are DRY-RUN by default. Set \`write: true\` to apply changes.
Output includes operation plan with line numbers, never values.

### envsitter_add
Add a NEW key (fails if key already exists).
\`\`\`json
{ "filePath": ".env", "key": "NEW_KEY", "value": "some-value", "write": true }
\`\`\`
Returns: \`{ file, key, hasChanges, plan: { action: "added"|"key_exists" } }\`

### envsitter_set
Create or update a key (upsert behavior).
\`\`\`json
{ "filePath": ".env", "key": "API_KEY", "value": "new-value", "write": true }
\`\`\`
Returns: \`{ file, key, hasChanges, plan: { action: "added"|"updated"|"no_change" } }\`

### envsitter_unset
Set a key to empty string (keeps the key line).
\`\`\`json
{ "filePath": ".env", "key": "OLD_KEY", "write": true }
\`\`\`
Returns: \`{ file, key, hasChanges, plan: { action: "unset"|"not_found" } }\`

### envsitter_delete
Remove key(s) entirely from the file.
\`\`\`json
{ "filePath": ".env", "keys": ["OLD_KEY", "UNUSED_KEY"], "write": true }
\`\`\`
Returns: \`{ file, keys, hasChanges, plan: [{ key, action: "deleted"|"not_found" }] }\`
`;

                    const fileOps = `
## File Operation Tools

### envsitter_validate
Check .env file syntax for errors.
\`\`\`json
{ "filePath": ".env" }
\`\`\`
Returns: \`{ file, ok: boolean, issues: [{ line, column, message }] }\`

### envsitter_copy
Copy keys between .env files. Dry-run unless \`write: true\`.
\`\`\`json
{
  "from": ".env.production",
  "to": ".env.staging",
  "keys": ["API_URL", "REDIS_URL"],
  "onConflict": "overwrite",
  "write": true
}
\`\`\`
Options: \`includeRegex\`, \`excludeRegex\`, \`rename\` (e.g., "OLD=NEW,A=B")
Returns: \`{ from, to, hasChanges, plan: [{ fromKey, toKey, action }] }\`

### envsitter_format / envsitter_reorder
Format/reorder a .env file. Dry-run unless \`write: true\`.
\`\`\`json
{ "filePath": ".env", "mode": "sections", "sort": "alpha", "write": true }
\`\`\`
Modes: \`sections\` (preserve section groupings), \`global\` (treat as flat list)
Sort: \`alpha\` (alphabetical), \`none\` (preserve order within sections)

### envsitter_annotate
Add a comment above a key. Dry-run unless \`write: true\`.
\`\`\`json
{ "filePath": ".env", "key": "DATABASE_URL", "comment": "Production DB only", "write": true }
\`\`\`
Returns: \`{ file, key, hasChanges, plan: { action: "inserted"|"updated"|"not_found" } }\`
`;

                    const sections: Record<string, string> = {
                        overview,
                        reading,
                        matching,
                        mutations,
                        file_ops: fileOps,
                    };

                    if (topic === "all") {
                        return [overview, reading, matching, mutations, fileOps].join("\n---\n");
                    }

                    return sections[topic] ?? overview;
                },
            }),
        },
        "tool.execute.before": async (input, output) => {
            const filePath = getFilePathFromArgs(output.args);
            if (!filePath) return;

            if (!isSensitiveDotEnvPath(filePath) && !isEnvSitterPepperPath(filePath)) return;

            if (input.tool === "read") {
                throw new Error(
                    "Reading `.env*` is blocked to prevent secret leaks. " +
                        "Use EnvSitter tools instead (never prints values). " +
                        "Call envsitter_help for comprehensive usage guide."
                );
            }

            if (input.tool === "edit" || input.tool === "write" || input.tool === "patch" || input.tool === "multiedit") {
                throw new Error(
                    "Editing `.env*` and `.envsitter/pepper` via standard tools is blocked. " +
                        "Use EnvSitter mutation tools: envsitter_add, envsitter_set, envsitter_unset, envsitter_delete. " +
                        "Call envsitter_help for comprehensive usage guide."
                );
            }
        },
    };
};

export default EnvSitterGuard;